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Sample records for hamstring muscle-tendon-bone unit

  1. Central Tendon Injuries of Hamstring Muscles: Case Series of Operative Treatment.

    Science.gov (United States)

    Lempainen, Lasse; Kosola, Jussi; Pruna, Ricard; Puigdellivol, Jordi; Sarimo, Janne; Niemi, Pekka; Orava, Sakari

    2018-02-01

    As compared with injuries involving muscle only, those involving the central hamstring tendon have a worse prognosis. Limited information is available regarding the surgical treatment of central tendon injuries of the hamstrings. To describe the operative treatment and outcomes of central tendon injuries of the hamstrings among athletes. Case series; Level of evidence, 4. Eight athletes (6 top level, 2 recreational) with central hamstring tendon injuries underwent magnetic resonance imaging and surgical treatment. The indication for surgery was recurrent (n = 6) or acute (n = 2) central hamstring tendon injury. All patients followed the same postoperative rehabilitation protocol, and return to play was monitored. Magnetic resonance imaging found a central tendon injury in all 3 hamstring muscles (long head of the biceps femoris, semimembranosus, and semitendinosus) with disrupted tendon ends. In acute and recurrent central tendon injuries, full return to play was achieved at 2.5 to 4 months. There were no adverse events during follow-up. Central tendon injuries of the hamstrings can be successfully repaired surgically after acute and recurrent ruptures.

  2. Central Tendon Injuries of Hamstring Muscles: Case Series of Operative Treatment

    Science.gov (United States)

    Lempainen, Lasse; Kosola, Jussi; Pruna, Ricard; Puigdellivol, Jordi; Sarimo, Janne; Niemi, Pekka; Orava, Sakari

    2018-01-01

    Background: As compared with injuries involving muscle only, those involving the central hamstring tendon have a worse prognosis. Limited information is available regarding the surgical treatment of central tendon injuries of the hamstrings. Purpose: To describe the operative treatment and outcomes of central tendon injuries of the hamstrings among athletes. Study Design: Case series; Level of evidence, 4. Methods: Eight athletes (6 top level, 2 recreational) with central hamstring tendon injuries underwent magnetic resonance imaging and surgical treatment. The indication for surgery was recurrent (n = 6) or acute (n = 2) central hamstring tendon injury. All patients followed the same postoperative rehabilitation protocol, and return to play was monitored. Results: Magnetic resonance imaging found a central tendon injury in all 3 hamstring muscles (long head of the biceps femoris, semimembranosus, and semitendinosus) with disrupted tendon ends. In acute and recurrent central tendon injuries, full return to play was achieved at 2.5 to 4 months. There were no adverse events during follow-up. Conclusion: Central tendon injuries of the hamstrings can be successfully repaired surgically after acute and recurrent ruptures. PMID:29479545

  3. The Masticatory Contractile Load Induced Expression and Activation of Akt1/PKBα in Muscle Fibers at the Myotendinous Junction within Muscle-Tendon-Bone Unit

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    Yüksel Korkmaz

    2010-01-01

    Full Text Available The cell specific detection of enzyme activation in response to the physiological contractile load within muscle-tendon-bone unit is essential for understanding of the mechanical forces transmission from muscle cells via tendon to the bone. The hypothesis that the physiological mechanical loading regulates activation of Akt1/PKBα at Thr308 and at Ser473 in muscle fibers within muscle-tendon-bone unit was tested using quantitative immunohistochemistry, confocal double fluorescence analysis, and immunoblot analysis. In comparison to the staining intensities in peripheral regions of the muscle fibers, Akt1/PKBα was detected with a higher staining intensity in muscle fibers at the myotendinous junction (MTJ areas. In muscle fibers at the MTJ areas, Akt1/PKBα is dually phosphorylated at Thr308 and Ser473. The immunohistochemical results were confirmed by immunoblot analysis. We conclude that contractile load generated by masticatory muscles induces local domain-dependent expression of Akt1/PKBα as well as activation by dually phosphorylation at Thr308 and Ser473 in muscle fibers at the MTJ areas within muscle-tendon-bone unit.

  4. The hamstring muscle complex

    NARCIS (Netherlands)

    van der Made, A. D.; Wieldraaijer, T.; Kerkhoffs, G. M.; Kleipool, R. P.; Engebretsen, L.; van Dijk, C. N.; Golanó, P.

    2015-01-01

    The anatomical appearance of the hamstring muscle complex was studied to provide hypotheses for the hamstring injury pattern and to provide reference values of origin dimensions, muscle length, tendon length, musculotendinous junction (MTJ) length as well as width and length of a tendinous

  5. Evaluation of the hamstring muscle complex following acute injury

    International Nuclear Information System (INIS)

    Koulouris, George; Connell, David

    2003-01-01

    To evaluate the imaging findings following acute hamstring injury. We retrospectively reviewed the imaging findings of hamstring muscle complex (HMC) strain in 170 patients referred to our institution over a 3-year period. A total of 179 injuries to the HMC were demonstrated in 170 patients (154 male, 16 female, mean age 28.2 years). The mean duration of symptoms was 4.7 days (range 1-10 days). MR imaging was performed in 97 cases and sonography in 102 cases (both modalities were performed in 20 examinations). Attention was directed to the frequency of muscle involvement, the location of the injury within the muscle-tendon unit, the extent of the injury and discriminating avulsion from muscle injury. Twenty-one patients had proximal tendon injury, with sixteen avulsions and five partial tears. Sixteen of these patients had surgical confirmation of hamstring avulsion from the ischial tuberosity (14 conjoint, 2 biceps femoris alone) and all were reliably diagnosed with MR imaging (16/16), but less so with sonography (7/12). Four distal tendon avulsions were also observed (three semitendinosus, one biceps femoris). With respect to muscle injury, the biceps femoris was most commonly injured (124/154). Semimembranosus was an uncommon muscle injury (21/154) and semitendinosus rare (9/154). Imaging can discriminate a hamstring tendon avulsion from musculotendinous strain and helps identify which patients necessitate surgical management as opposed to conservative treatment. (orig.)

  6. Evaluation of the hamstring muscle complex following acute injury

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    Koulouris, George; Connell, David [Department of Radiology, St Francis X Cabrini, Wattletree Rd, 3144, Malvern, Victoria (Australia)

    2003-10-01

    To evaluate the imaging findings following acute hamstring injury. We retrospectively reviewed the imaging findings of hamstring muscle complex (HMC) strain in 170 patients referred to our institution over a 3-year period. A total of 179 injuries to the HMC were demonstrated in 170 patients (154 male, 16 female, mean age 28.2 years). The mean duration of symptoms was 4.7 days (range 1-10 days). MR imaging was performed in 97 cases and sonography in 102 cases (both modalities were performed in 20 examinations). Attention was directed to the frequency of muscle involvement, the location of the injury within the muscle-tendon unit, the extent of the injury and discriminating avulsion from muscle injury. Twenty-one patients had proximal tendon injury, with sixteen avulsions and five partial tears. Sixteen of these patients had surgical confirmation of hamstring avulsion from the ischial tuberosity (14 conjoint, 2 biceps femoris alone) and all were reliably diagnosed with MR imaging (16/16), but less so with sonography (7/12). Four distal tendon avulsions were also observed (three semitendinosus, one biceps femoris). With respect to muscle injury, the biceps femoris was most commonly injured (124/154). Semimembranosus was an uncommon muscle injury (21/154) and semitendinosus rare (9/154). Imaging can discriminate a hamstring tendon avulsion from musculotendinous strain and helps identify which patients necessitate surgical management as opposed to conservative treatment. (orig.)

  7. Evaluation of the hamstring muscles after injury

    International Nuclear Information System (INIS)

    Koulouris, G.; Connell, D.; Burke, F.; Young, D.

    2002-01-01

    Full text: The aim of this study was to describe the imaging findings following acute hamstring injury. We retrospectively reviewed the imaging findings of 224 examinations in 208 patients (192 male, 16 female, mean age 28.2 years). MR imaging was performed in 102 cases and sonography in 156 cases (both modalities were performed in 34 examinations). The mean duration of symptoms was 4.7 days (range 1-10 days). Attention was directed to the frequency of muscle movement, the location of the injury within the musculotendinous unit, the extent of the injury and discriminating avulsion from musculotendinous injury. Sixteen patients underwent surgery. The biceps femoris was the most common muscle injured (150/224). Sixteen patients with surgical confirmation of a hamstring avulsion from the ischial tuberosity (14 conjoint, 2 biceps alone) were reliably diagnosed with MR imaging (16/16), but less so with ultrasound (7/12). Eighty-six patients (86/150) had injuries of the musculotendinous junction of biceps, 51/150 myofascial injuries and 13/150 muscle belly alone. Proximal injuries of the biceps were more common that the distal. Sixty-eight patients had injuries of semitendinosus and eight patients semimebranosus.The semitendinosus muscle was more often injured in the distal half of the muscle (42/68) as was semimebranosus (7/8). Three patients had a distal rupture of semitendinosus muscle with retraction. Haematoma was a common finding (170/224) and often tracked around the myofascial layer.This was felt to be a reliable sign for hamstring injury. Discriminating a hamstring tendon avulsion from myotendinous strain is important as these patients necessitate surgical management as opposed to conservative treatment. MR imaging is the preferred modality in the investigation of hamstring muscle and tendon injury. Ultrasound has a complimentary role and may be used to monitor hamstring tendon injuries prior to return to competitive sport. Copyright (2002) Blackwell Science Pty

  8. Knee extension and flexion muscle power after anterior cruciate ligament reconstruction with patellar tendon graft or hamstring tendons graft: a cross-sectional comparison 3 years post surgery

    DEFF Research Database (Denmark)

    Ageberg, Eva; Roos, Harald; Silbernagel, Karin

    2008-01-01

    Hamstring muscles play a major role in knee-joint stabilization after anterior cruciate ligament (ACL) injury. Weakness of the knee extensors after ACL reconstruction with patellar tendon (PT) graft, and in the knee flexors after reconstruction with hamstring tendons (HT) graft has been observed ...

  9. Do peak torque angles of muscles change following anterior cruciate ligament reconstruction using hamstring or patellar tendon graft?

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    Yosmaoğlu, Hayri Baran; Baltacı, Gül; Sönmezer, Emel; Özer, Hamza; Doğan, Deha

    2017-12-01

    This study aims to compare the effects of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring or patellar tendon graft on the peak torque angle. The study included 132 patients (103 males, 29 females; mean age 29±9 year) who were performed ACL reconstruction with autogenous hamstring or patellar tendon graft. The peak torque angles in the quadriceps and hamstring muscles were recorded using an isokinetic dynamometer. Angle of peak knee flexion torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the hamstring tendon group. Angle of peak knee extension torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the patellar tendon group. There were no statistically significant differences in the flexion and extension peak torque angles between the operated and nonoperated knees at 60°/second in both groups. The angle of peak torque at relatively high angular velocities is affected after ACL reconstruction in patients with hamstring or patellar tendon grafts. The graft donor site directly influences this parameter. This finding may be important for clinicians in terms of preventing re-injury.

  10. [Isokinetic assessment with two years follow-up of anterior cruciate ligament reconstruction with patellar tendon or hamstring tendons].

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    Condouret, J; Cohn, J; Ferret, J-M; Lemonsu, A; Vasconcelos, W; Dejour, D; Potel, J-F

    2008-12-01

    This retrospective multicentric study was designed to assess the outcome of quadriceps and hamstrings muscles two years after Anterior Cruciate Ligament (ACL) reconstruction and compare muscles recovery depending on the type of graft and individual variables like age, gender, level of sport, but also in terms of discomfort, pain and functional score. The results focused on the subjective and objective IKDC scores, SF36, the existence or not of subjective disorders and their location. The review included isokinetic muscle tests concentric and eccentric extensors/flexors but also internal rotators/external rotators with analysis of mean work and mean power. One hundred and twenty-seven patients were included with an average age 29 years (+/-10). They all had an ACL reconstruction with patellar tendon or hamstring tendon with single or double bundles. In the serie, the average muscles deficit at two years was 10% for the flexors and extensors but with a significant dispersion. Significant differences were not noted in the mean values of all parameters in term of sex or age (over 30 years or not), neither the type of sport, nor of clinical assessment (Class A and B of objective IKDC score), nor the existence of anterior knee pain. There was a relationship between the level of extensor or flexor recovery and the quality of functional results with minimal muscle deficits close to 5% if the IKDC score was over 90 and deficits falling to 15% in the group with IKDC score less than 90. The type of reconstruction (patellar tendon versus hamstrings) had an influence on the muscle deficit. For extensors, the recovery was the same in the two groups, more than 90% at two years and the distribution of these two populations by level of deficit was quite the same. For flexors, residual deficits were significantly higher in the hamstrings group on the three studied parameters whatever the speed and the type of contraction (concentric or eccentric) with an average deficit of 14 to 18

  11. Complete rupture of the distal semimembranosus tendon with secondary hamstring muscles atrophy: MR findings in two cases

    International Nuclear Information System (INIS)

    Varela, J.R.; Rodriguez, E.; Soler, R.; Gonzalez, J.; Pombo, S.

    2000-01-01

    Complete rupture of the hamstring muscles is a rare injury. The proximal musculo-tendinous junction is the most frequent site of rupture. We present two cases of complete rupture of the distal semimenbranosus tendon, which clinically presented as soft-tissue masses. MR imaging permitted the correct diagnosis. There has been only one other such case reported. (orig.)

  12. Complete rupture of the distal semimembranosus tendon with secondary hamstring muscles atrophy: MR findings in two cases

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    Varela, J.R.; Rodriguez, E.; Soler, R.; Gonzalez, J.; Pombo, S. [Dept. of Radiology, Hospital Juan Canalejo, La Coruna (Spain)

    2000-06-01

    Complete rupture of the hamstring muscles is a rare injury. The proximal musculo-tendinous junction is the most frequent site of rupture. We present two cases of complete rupture of the distal semimenbranosus tendon, which clinically presented as soft-tissue masses. MR imaging permitted the correct diagnosis. There has been only one other such case reported. (orig.)

  13. The proximal hamstring muscle–tendon–bone unit: A review of the normal anatomy, biomechanics, and pathophysiology

    International Nuclear Information System (INIS)

    Beltran, Luis; Ghazikhanian, Varand; Padron, Mario; Beltran, Javier

    2012-01-01

    Proximal hamstring injuries occur during eccentric contraction with the hip and the knee on extension; hence they are relatively frequent lesions in specific sports such as water skiing and hurdle jumping. Additionally, the trend toward increasing activity and fitness training in the general population has resulted in similar injuries. Myotendinous strains are more frequent than avulsion injuries. Discrimination between the two types of lesions is relevant for patient management, since the former is treated conservatively and the latter surgically. MRI and Ultrasonography are both well suited techniques for the diagnosis and evaluation of hamstring tendon injuries. Each one has its advantages and disadvantages. The purpose of this article is to provide a comprehensive review of the anatomy and biomechanics of the proximal hamstring muscle–tendon–bone unit and the varied imaging appearances of hamstring injury, which is vital for optimizing patient care. This will enable the musculoskeletal radiologist to contribute accurate and useful information in the treatment of athletes at all levels of participation.

  14. The proximal hamstring muscle–tendon–bone unit: A review of the normal anatomy, biomechanics, and pathophysiology

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    Beltran, Luis, E-mail: luisbeltran@mac.com [Department of Radiology, Hospital for Joint Diseases, NYU, New York, NY (United States); Ghazikhanian, Varand, E-mail: varandg@aol.com [Department of Radiology, Maimonides Medical Center, Brooklyn, NY (United States); Padron, Mario, E-mail: mario.padron@cemtro.es [Clinica CEMTRO, Avenida del Ventisquero de la Condesa 42, 28035 Madrid (Spain); Beltran, Javier, E-mail: Jbeltran46@msn.com [Department of Radiology, Maimonides Medical Center, Brooklyn, NY (United States)

    2012-12-15

    Proximal hamstring injuries occur during eccentric contraction with the hip and the knee on extension; hence they are relatively frequent lesions in specific sports such as water skiing and hurdle jumping. Additionally, the trend toward increasing activity and fitness training in the general population has resulted in similar injuries. Myotendinous strains are more frequent than avulsion injuries. Discrimination between the two types of lesions is relevant for patient management, since the former is treated conservatively and the latter surgically. MRI and Ultrasonography are both well suited techniques for the diagnosis and evaluation of hamstring tendon injuries. Each one has its advantages and disadvantages. The purpose of this article is to provide a comprehensive review of the anatomy and biomechanics of the proximal hamstring muscle–tendon–bone unit and the varied imaging appearances of hamstring injury, which is vital for optimizing patient care. This will enable the musculoskeletal radiologist to contribute accurate and useful information in the treatment of athletes at all levels of participation.

  15. Free Bone Plug Quadriceps Tendon Harvest and Suspensory Button Attachment for Anterior Cruciate Ligament Reconstruction.

    Science.gov (United States)

    Todor, Adrian; Caterev, Sergiu; Nistor, Dan Viorel; Khallouki, Youssef

    2016-06-01

    The most commonly used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and hamstring tendons. Each has its advantages and limitations. The bone-patellar tendon-bone autograft can lead to more donor-site morbidity, and the hamstring autograft can be unpredictable in size. The quadriceps tendon, with or without a bone block, has been described as an alternative graft source and has been used especially in revision cases, but in recent years, it has attracted attention even for primary cases. We report a technique for harvesting a free bone quadriceps tendon graft and attaching an extracortical button for femoral fixation for anterior cruciate ligament reconstruction.

  16. Anterior-Posterior Instability of the Knee Following ACL Reconstruction with Bone-Patellar Tendon-Bone Ligament in Comparison with Four-Strand Hamstrings Autograft

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    A. G. Angoules

    2013-01-01

    Full Text Available Purpose. To evaluate anterior-posterior knee laxity using two different autografts. Material-Methods. 40 patients, (34 males and 6 women, 17–54 years old (mean: 31, were included in the present study. Group A (4SHS = 20 underwent reconstruction using four-strand hamstrings, and group B (BPBT = 20 underwent reconstruction using bone-patellar tendon-bone autograft. Using the KT-1000 arthrometer, knee instability was calculated in both knees of all patients preoperatively and 3, 6, and 12 months after surgery at the ACL-operated knee. The contralateral healthy knee was used as an internal control group. Results. Anterior-posterior instability using the KT1000 Arthrometer was found to be increased after ACL insufficiency. The recorded laxity improved after arthroscopic ACL reconstruction in both groups. However, statistically significant greater values were detected in the bone-patellar tendon-bone group, which revealed reduction of anteroposterior stability values to an extent, where no statistical significance with the normal values even after 3 months after surgery was observed. Conclusions. Anterior-Posterior instability of the knee improved significantly after arthroscopic ACL reconstruction. The bone-patellar tendon-bone graft provided an obvious greater stability.

  17. Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair.

    Science.gov (United States)

    Lightsey, Harry M; Kantrowitz, David E; Swindell, Hasani W; Trofa, David P; Ahmad, Christopher S; Lynch, T Sean

    2018-02-01

    The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Cross-sectional study. Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises. Fifteen protocols (43%) required completion of

  18. Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair

    Science.gov (United States)

    Lightsey, Harry M.; Kantrowitz, David E.; Swindell, Hasani W.; Trofa, David P.; Ahmad, Christopher S.; Lynch, T. Sean

    2018-01-01

    Background: The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. Purpose: To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Study Design: Cross-sectional study. Methods: Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Results: Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises

  19. Muscle and intensity based hamstring exercise classification in elite female track and field athletes: implications for exercise selection during rehabilitation

    Science.gov (United States)

    Tsaklis, Panagiotis; Malliaropoulos, Nikos; Mendiguchia, Jurdan; Korakakis, Vasileios; Tsapralis, Kyriakos; Pyne, Debasish; Malliaras, Peter

    2015-01-01

    Background Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises. Methods Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG) was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC) was used to normalize the mean data across ten repetitions of each exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student’s t-test. Results The lunge, dead lift, and kettle swings were low intensity (hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs. PMID:26170726

  20. Changes in hip joint muscle-tendon lengths with mode of locomotion.

    Science.gov (United States)

    Riley, Patrick O; Franz, Jason; Dicharry, Jay; Kerrigan, D Casey

    2010-02-01

    We have reported that peak hip extension is nearly identical in walking and running, suggesting that anatomical constraints, such as flexor muscle tightness may limit the range of hip extension. To obtain a more mechanistic insight into mobility at the hip and pelvis we examined the lengths of the muscle-tendons units crossing the hip joint. Data defining the three-dimensional kinematics of 26 healthy runners at self-selected walking and running speeds were obtained. These data were used to scale and drive musculoskeletal models using OpenSIM. Muscle-tendon unit (MTU) lengths were calculated for the trailing limb illiacus, rectus femoris, gluteus maximus, and biceps femoris long head and the advancing limb biceps femoris and gluteus maximus. The magnitude and timing of MTU length peaks were each compared between walking and running. The peak length of the right (trailing limb) illiacus MTU, a pure hip flexor, was nearly identical between walking and running, while the maximum length of the rectus femoris MTU, a hip flexor and knee extensor, increased during running. The maximum length of the left (leading limb) biceps femoris was also unchanged between walking and running. Further, the timing of peak illiacus MTU length and peak contralateral biceps femoris MTU length occurred essentially simultaneously during running, at a time during gait when the hamstrings are most vulnerable to stretch injury. This latter finding suggests exploring the role for hip flexor stretching in combination with hamstring stretching to treat and/or prevent running related hamstring injury. Copyright 2009 Elsevier B.V. All rights reserved.

  1. Relationships among hamstring muscle optimal length and hamstring flexibility and strength

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    Xianglin Wan

    2017-09-01

    Conclusion: Hamstring flexibility may affect hamstring muscle maximum strain in movements. With similar hamstring flexibility, hamstring muscle maximal strain in a given movement may be different between genders. Hamstring muscle lengths in standing should not be used as an approximation of their optimal lengths in calculation of hamstring muscle strain in musculoskeletal system modeling.

  2. Relationships among hamstring muscle optimal length and hamstring flexibility and strength

    OpenAIRE

    Xianglin Wan; Feng Qu; William E. Garrett; Hui Liu; Bing Yu

    2017-01-01

    Background: Hamstring muscle strain injury (hamstring injury) due to excessive muscle strain is one of the most common injuries in sports. The relationships among hamstring muscle optimal lengths and hamstring flexibility and strength were unknown, which limited our understanding of risk factors for hamstring injury. This study was aimed at examining the relationships among hamstring muscle optimal length and flexibility and strength. Methods: Hamstring flexibility and isokinetic strength ...

  3. ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: A COMPARISON BETWEEN BONE PATELLAR TENDON BONE GRAFT AND LIPSCOMB PROCEDURE - A FOLLOWUP STUDY OF 7 YEARS

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    Vijayamohan S

    2016-07-01

    Full Text Available BACKGROUND Anterior Cruciate Ligament injury has become more common and the demand by the patients to return to pre-injury level of activity has made reconstruction of the ligament very crucial. Though there are various techniques in reconstructing the anterior cruciate ligament, in this study, we compare two most commonly used techniques to see whether there is any significant difference in the outcome. METHODS Study included 25 patients in the age group of 19-36 years, of which 23 were males. The patients were divided randomly into 2 groups, and 15 patients underwent Anterior Cruciate Ligament reconstruction using Bone Patellar Tendon Bone Graft and 10 patients had Hamstring graft. RESULTS Patients were followed up at regular intervals monthly for the first six months and then at three monthly intervals. Patients were assessed using Knee Scoring Scale of Lysholm and Gillquist and International Knee Documentation Committee (IKDC scoring system. In addition, activity level, harvest site pain, thigh atrophy, kneeling pain and hamstring pain were assessed. All patients were followed up for a minimum period of 2 years. 20% of both groups were able to return to strenuous activity level, and 67% of Patellar tendon group and 50% of the Hamstring tendon group were able to return to moderate level of activity. 55% of patients in the patellar tendon group and 20% of patients in the hamstring tendon group had donor site pain in the first 6 months. 73% of patients in the hamstring group had at least 10 mm of thigh wasting. Pain on kneeling was seen only in the patellar tendon group (35% while hamstring pain was found only in the hamstring group (20%. CONCLUSIONS Patients in the patellar tendon group had increased anterior stability and were able to return to strenuous occupation. The difference in thigh atrophy between the two groups was not significant. The hamstring group had lower graft harvest site morbidity. Lachman test was the single most accurate

  4. Passive Muscle-Tendon Unit Gearing is Joint Dependent in Human Medial Gastrocnemius

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    Emma F Hodson-Tole

    2016-03-01

    Full Text Available Skeletal muscles change length and develop force both passively and actively. Gearing allows muscle fibre length changes to be uncoupled from those of the whole muscle-tendon unit. During active contractions this process allows muscles to operate at mechanically favorable conditions for power or economical force production. Here we ask whether gearing is constant in passive muscle; determining the relationship between fascicle and muscle-tendon unit length change in the bi-articular medial gastrocnemius and investigating the influence of whether motion occurs at the knee or ankle joint. Specifically, the same muscle-tendon unit length changes were elicited by rotating either the ankle or knee joint whilst simultaneously measuring fascicle lengths in proximal and distal muscle regions using B-mode ultrasound. In both the proximal and distal muscle region, passive gearing values differed depending on whether ankle or knee motion occurred. Fascicle length changes were greater with ankle motion, likely reflecting anatomical differences in proximal and distal passive tendinous tissues, as well as shape changes of the adjacent mono-articular soleus. This suggests that there is joint-dependent dissociation between the mechanical behaviour of muscle fibres and the muscle-tendon unit during passive joint motions that may be important to consider when developing accurate models of bi-articular muscles.

  5. Anatomical study of the proximal origin of hamstring muscles.

    Science.gov (United States)

    Sato, Kengo; Nimura, Akimoto; Yamaguchi, Kumiko; Akita, Keiichi

    2012-09-01

    It is relatively well accepted that the long head of the biceps femoris and the semitendinosus both originate from the ischial tuberosity as a common tendon. However, it is also widely known that the biceps femoris is consistently injured more than the semitendinosus. The purpose of this study was to examine the origins of the hamstring muscles, to find an anatomic basis for diagnosis and treatment of injuries of the posterior thigh regions. Twenty-eight hips of fourteen adult Japanese cadavers were used in this study. In twenty hips of ten cadavers, the positional relationships among the origins on the ischial tuberosity were examined. In eight hips of four cadavers, histological examination of the origins of the hamstrings was also performed. The origin of the long head of the biceps femoris adjoined that of the semitendinosus. In the proximal regions of these muscles, the long head consisted of the tendinous part; however, the semitendinosus mainly consisted of the muscular part. Some of the fibers of the biceps tendon extended to fuse with the sacrotuberous ligament. The semimembranosus muscle broadly originated from the lateral surface of the ischial tuberosity. The origins of the long head of the biceps femoris and the semitendinosus are found to be almost independent, and the tendon of the long head is partly fused with the sacrotuberous ligament. The high incidence of injuries to the long head of the biceps femoris could be explained by these anatomical configurations.

  6. The effect of hamstring flexibility on peak hamstring muscle strain in sprinting

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    Xianglin Wan

    2017-09-01

    Conclusion: A potential for hamstring injury exists during the late swing phase of sprinting. Peak hamstring muscle strains in sprinting are negatively correlated to hamstring flexibility across individuals. The magnitude of peak muscle strains is different among hamstring muscles in sprinting, which may explain the different injury rate among hamstring muscles.

  7. Muscle and intensity based hamstring exercise classification in elite female track and field athletes: implications for exercise selection during rehabilitation

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    Tsaklis P

    2015-06-01

    exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student's t-test.Results: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC. The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed.Conclusion: Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.Keywords: hamstring injuries, exercise, rehabilitation

  8. Abduction in Proximal Hamstring Tendon Avulsion Injury Mechanism-A Report on 3 Athletes

    NARCIS (Netherlands)

    van der Made, Anne D.; Peters, Rolf W.; Verheul, Claire; Maas, Mario; Kerkhoffs, Gino M.

    2017-01-01

    Proximal hamstring tendon avulsions are typically sustained during forced hip hyperflexion combined with knee extension. We present 3 cases of athletes with a proximal hamstring tendon avulsion caused by an alternative injury mechanism that also involves a considerable hip abduction component

  9. The effect of hamstring flexibility on peak hamstring muscle strain in sprinting

    OpenAIRE

    Xianglin Wan; Feng Qu; William E. Garrett; Hui Liu; Bing Yu

    2017-01-01

    Background: The effect of hamstring flexibility on the peak hamstring muscle strains in sprinting, until now, remained unknown, which limited our understanding of risk factors of hamstring muscle strain injury (hamstring injury). As a continuation of our previous study, this study was aimed to examine the relationship between hamstring flexibility and peak hamstring muscle strains in sprinting. Methods: Ten male and 10 female college students participated in this study. Hamstring flexibili...

  10. Pain level after ACL reconstruction: A comparative study between free quadriceps tendon and hamstring tendons autografts.

    Science.gov (United States)

    Buescu, Cristian Tudor; Onutu, Adela Hilda; Lucaciu, Dan Osvald; Todor, Adrian

    2017-03-01

    The objective of this study was to compare the pain levels and analgesic consumption after single bundle ACL reconstruction with free quadriceps tendon autograft versus hamstring tendon autograft. A total of 48 patients scheduled for anatomic single-bundle ACL reconstruction were randomized into two groups: the free quadriceps tendon autograft group (24 patients) and the hamstring tendons autograft group (24 patients). A basic multimodal analgesic postoperative program was used for all patients and rescue analgesia was provided with tramadol, at pain scores over 30 on the Visual Analog Scale. The time to the first rescue analgesic, the number of doses of tramadol and pain scores were recorded. The results within the same group were compared with the Wilcoxon signed test. Supplementary analgesic drug administration proved significantly higher in the group of subjects with hamstring grafts, with a median (interquartile range) of 1 (1.3) dose, compared to the group of subjects treated with a quadriceps graft, median = 0.5 (0.1.25) (p = 0.009). A significantly higher number of subjects with a quadriceps graft did not require any supplementary analgesic drug (50%) as compared with subjects with hamstring graft (13%; Z-statistics = 3.01, p = 0.002). The percentage of subjects who required a supplementary analgesic drug was 38% higher in the HT group compared with the FQT group. The use of the free quadriceps tendon autograft for ACL reconstruction leads to less pain and analgesic consumption in the immediate postoperative period compared with the use of hamstrings autograft. Level I Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  11. Estimation of tensile force in the hamstring muscles during overground sprinting.

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    Ono, T; Higashihara, A; Shinohara, J; Hirose, N; Fukubayashi, T

    2015-02-01

    The purpose of this study was to identify the period of the gait cycle during which the hamstring muscles were likely injured by estimating the magnitude of tensile force in each muscle during overground sprinting. We conducted three-dimensional motion analysis of 12 male athletes performing overground sprinting at their maximal speed and calculated the hamstring muscle-tendon length and joint angles of the right limb throughout a gait cycle during which the ground reaction force was measured. Electromyographic activity during sprinting was recorded for the biceps femoris long head, semitendinosus, and semimembranosus muscles of ipsilateral limb. We estimated the magnitude of tensile force in each muscle by using the length change occurred in the musculotendon and normalized electromyographic activity value. The study found a quick increase of estimated tensile force in the biceps femoris long head during the early stance phase of the gait cycle during which the increased hip flexion angle and ground reaction force occurred at the same time. This study provides quantitative data of tensile force in the hamstring muscles suggesting that the biceps femoris long head muscle is susceptible to a strain injury during the early stance phase of the sprinting gait cycle. © Georg Thieme Verlag KG Stuttgart · New York.

  12. Risk of iatrogenic injury to the infrapatellar branch of the saphenous nerve during hamstring tendon harvesting: A meta-analysis.

    Science.gov (United States)

    Pękala, Przemysław A; Tomaszewski, Krzysztof A; Henry, Brandon Michael; Ramakrishnan, Piravin Kumar; Roy, Joyeeta; Mizia, Ewa; Walocha, Jerzy A

    2017-11-01

    Our goal was to conduct a comprehensive analysis of studies reporting data on the rate of injury to the infrapatellar branch of the saphenous nerve following hamstring tendon graft harvesting with respect to the type of incision over the pes anserinus. A broad search through all major electronic databases was conducted to identify articles eligible for inclusion. All available data were extracted and pooled into the analysis. Eleven studies (n = 1,050 patients) were included in the meta-analysis. The study revealed that a vertical incision during hamstring tendon harvesting over the pes anserinus was associated with the highest rate of injury with a pooled rate of 51.4% (95% confidence interval [CI], 34.6-67.2%). This was followed by oblique and horizontal incisions with pooled rates of 26.0% (95% CI,1.3-61.3%) and 22.4% (95% CI, 5.4-45.5%), respectively. We highly recommend the use of the shortest possible oblique incision during hamstring tendon harvesting over the pes anserinus. Muscle Nerve 56: 930-937, 2017. © 2017 Wiley Periodicals, Inc.

  13. BONE TUNNEL WIDENING AFTER ANTERIOR CRUCIATE LIGAMENT AUTOPLASTY WITH HAMSTRINGS (LITERATURE REVIEW

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    V. V. Slastinin

    2017-01-01

    Full Text Available ABSTRACT Such a phenomenon as bone tunnel widening after anterior cruciate ligament autoplasty with hamstrings has been known for 30 years. Despite the long history of this issue, the etiology is still not fully understood. The process of expansion of the bone tunnels is influenced by many factors such as graft fixation technique, surgical technique and rehabilitation protocol, as well as various biological factors. It is believed that this phenomenon has no influence on a functional result, but may create serious problems in revision anterior cruciate ligament surgery. Given the growing interest in the use of hamstring tendon grafts for anterior cruciate ligament reconstruction, increasing number of these operations and as a result, of revision procedures, the search for methods of bone tunnel widening prevention is becoming more urgent.

  14. A retrospective review of bone tunnel enlargement after anterior cruciate ligament reconstruction with hamstring tendons fixed with a metal round cannulated interference screw in the femur.

    Science.gov (United States)

    Kobayashi, Masahiko; Nakagawa, Yasuaki; Suzuki, Takashi; Okudaira, Shuzo; Nakamura, Takashi

    2006-10-01

    To assess bone tunnel enlargement after anterior cruciate ligament (ACL) reconstruction with the use of hamstring tendons fixed with a round cannulated interference (RCI) screw in the femur. A consecutive series of 30 ACL reconstructions performed with hamstring tendons fixed with an RCI screw in the femur and with staples via Leeds-Keio ligament in the tibia was retrospectively reviewed. The clinical outcome was evaluated through the Lysholm score. Anterior instability was tested by Telos-SE (Telos Japan, Tokyo, Japan) measurement. The location and angle of each femoral and tibial tunnel were measured with the use of plain radiographs, and bone tunnel enlargement greater than 2 mm detected any time 3, 6, 12, and 24 months postoperatively was defined as positive. Each factor (location and angle of the tunnels, sex, affected side, age, Lysholm score, and Telos-SE measurement) was compared between enlarged and nonenlarged groups. Positive enlargement of the bone tunnel (>2.0 mm) was observed in 36.7% (11 of 30) on the femoral side and 33.3% (10 of 30) on the tibial side, and in 6 knees of both sides. Half of patients (15 of 30) had an enlarged tunnel on the femoral or the tibial side until 1 year postoperatively. In most cases, enlargement reached maximum at 6 months postoperatively. Female patients tended to have an enlarged tunnel, especially on the femoral side (P < .05). Tunnel enlargement was not correlated with location and angle of the tunnels. Moreover, no difference was found in Lysholm score and Telos-SE measurement between enlarged and nonenlarged groups, although the nonenlarged group tended to exhibit higher Lysholm score and lesser instability. Bone tunnel enlargement of the femoral or tibial side was observed in half of patients (6 in both sides, 5 only in the femur, and 4 only in the tibia) after ACL reconstruction was performed with a hamstring tendon fixed with an RCI screw. Female patients had a greater chance for enlargement of the femoral tunnel

  15. Hydroxyapatite-doped polycaprolactone nanofiber membrane improves tendon-bone interface healing for anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Han, Fei; Zhang, Peng; Sun, Yaying; Lin, Chao; Zhao, Peng; Chen, Jiwu

    2015-01-01

    Hamstring tendon autograft is a routine graft for anterior cruciate ligament (ACL) reconstruction. However, ways of improving the healing between the tendon and bone is often overlooked in clinical practice. This issue can be addressed by using a biomimetic scaffold. Herein, a biomimetic nanofiber membrane of polycaprolactone/nanohydroxyapatite/collagen (PCL/nHAp/Col) is fabricated that mimics the composition of native bone tissue for promoting tendon-bone healing. This membrane has good cytocompatibility, allowing for osteoblast cell adhesion and growth and bone formation. As a result, MC3T3 cells reveal a higher mineralization level in PCL/nHAp/Col membrane compared with PCL membrane alone. Further in vivo studies in ACL reconstruction in a rabbit model shows that PCL/nHAp/Col-wrapped tendon may afford superior tissue integration to nonwrapped tendon in the interface between the tendon and host bone as well as improved mechanical strength. This study shows that PCL/nHAp/Col nanofiber membrane wrapping of autologous tendon is effective for improving tendon healing with host bone in ACL reconstruction.

  16. COMPARISON OF HAMSTRING MUSCLE ACTIVATION DURING HIGH-SPEED RUNNING AND VARIOUS HAMSTRING STRENGTHENING EXERCISES

    Science.gov (United States)

    Solheim, Jens Asmund Brevik; Bencke, Jesper

    2017-01-01

    Purpose/Background Several studies have examined the effect of hamstring strength exercises upon hamstring strains in team sports that involve many sprints. However, there has been no cross comparison among muscle activation of these hamstring training exercises with actual sprinting. Therefore, the aim of this study was to examine different hamstring exercises and compare the muscle activity in the hamstring muscle group during various exercises with the muscular activity produced during maximal sprints. Methods Twelve male sports students (age 25 ± 6.2 years, 1.80 ± 7.1 m, body mass 81.1 ± 15.6 kg) participated in this study. Surface EMG electrodes were placed on semimembranosus, semitendinosus and biceps femoris to measure muscle activity during seven hamstrings exercises and sprinting together with 3D motion capture to establish at what hip and knee angles maximal muscle activation (EMG) occurs. Maximal EMG activity during sprints for each muscle was used in order to express each exercise as a percentage of max activation during sprinting. Results The main findings were that maximal EMG activity of the different hamstring exercises were on average between 40-65% (Semitendinosus), 18-40% (biceps femoris) and 40-75% (Semimembranosus) compared with the max EMG activity in sprints, which were considered as 100%. The laying kick together with the Nordic hamstring exercises and its variations had the highest muscle activations, while the cranes showed the lowest muscle activation (in all muscles) together with the standing kick for the semimembranosus. In addition, angles at which the peak EMG activity of the hamstring muscle occurs were similar for the Nordic hamstring exercises and different for the two crane exercises (hip angle), standing kick (hip angle) and the laying kick (knee angle) compared with the sprint. Conclusions Nordic hamstring exercises with its variation together with the laying kick activates the hamstrings at high levels and

  17. Physical principles demonstrate that the biceps femoris muscle relative to the other hamstring muscles exerts the most force: implications for hamstring muscle strain injuries.

    Science.gov (United States)

    Dolman, Bronwyn; Verrall, Geoffrey; Reid, Iain

    2014-07-01

    Of the hamstring muscle group the biceps femoris muscle is the most commonly injured muscle in sports requiring interval sprinting. The reason for this observation is unknown. The objective of this study was to calculate the forces of all three hamstring muscles, relative to each other, during a lengthening contraction to assess for any differences that may help explain the biceps femoris predilection for injury during interval sprinting. To calculate the displacement of each individual hamstring muscle previously performed studies on cadaveric anatomical data and hamstring kinematics during sprinting were used. From these displacement calculations for each individual hamstring muscle physical principles were then used to deduce the proportion of force exerted by each individual hamstring muscle during a lengthening muscle contraction. These deductions demonstrate that the biceps femoris muscle is required to exert proportionally more force in a lengthening muscle contraction relative to the semimembranosus and semitendinosus muscles primarily as a consequence of having to lengthen over a greater distance within the same time frame. It is hypothesized that this property maybe a factor in the known observation of the increased susceptibility of the biceps femoris muscle to injury during repeated sprints where recurrent higher force is required.

  18. Knee flexor strength recovery following hamstring tendon harvest for anterior cruciate ligament reconstruction: a systematic review

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    Clare Ardern

    2009-07-01

    Full Text Available The hamstring tendons are an increasingly popular graft choice for anterior cruciate ligament reconstruction due to preservation of quadriceps function and the absence of anterior knee pain post-operatively. Two commonly used hamstring grafts are a quadruple strand semitendinosus graft (4ST and a double strand semitendinosus-double strand gracilis graft (2ST-2G. It has been suggested that concurrent harvest of the semitendinsous and gracilis tendons may result in sub-optimal hamstring strength recovery as the gracilis may play a role in reinforcing the semitendinosus particularly in deep knee flexion angles. The objective of this systematic review was to synthesize the findings of available literature and determine whether semitendinosus and gracilis harvest lead to post-operative hamstring strength deficits when compared to semitendinosus harvest alone. Seven studies were identified which compared hamstring strength outcomes between the common hamstring graft types. The methodological quality of each paper was assessed, and where possible effect sizes were calculated to allow comparison of results across studies. No differences were reported between the groups in isokinetic hamstring strength. Deficits in hamstring strength were reported in the 2ST-2G groups when compared to the 4ST groups in isometric strength testing at knee flexion angles ≥70°, and in the standing knee flexion angle. Preliminary evidence exists to support the hypothesis that harvesting the semitendinosus tendon alone is preferable to harvesting in combination with the gracilis tendon for minimizing post-operative hamstring strength deficits at knee flexion angles greater than 70°. However, due to the paucity of research comparing strength outcomes between the common hamstring graft types, further investigation is warranted to fully elucidate the implications for graft harvest.

  19. Architectural differences between the hamstring muscles.

    Science.gov (United States)

    Kellis, Eleftherios; Galanis, Nikiforos; Kapetanos, George; Natsis, Konstantinos

    2012-08-01

    The purpose of this study was to understand the detailed architectural properties of the human hamstring muscles. The long (BFlh) and short (BFsh) head of biceps femoris, semimembranosus (SM) and semitendinosus (ST) muscles were dissected and removed from their origins in eight cadaveric specimens (age 67.8±4.3 years). Mean fiber length, sarcomere length, physiological cross-section area and pennation angle were measured. These data were then used to calculate a similarity index (δ) between pairs of muscles. The results indicated moderate similarity between BFlh and BFsh (δ=0.54) and between BFlh and SM (δ=0.35). In contrast, similarity was low between SM and ST (δ=0.98) and between BFlh and SM (δ=1.17). The fascicle length/muscle length ratio was higher for the ST (0.58) and BFsh (0.50) compared with the BFlh (0.27) and SM (0.22). There were, however, high inter-correlations between individual muscle architecture values, especially for muscle thickness and fascicle length data sets. Prediction of the whole hamstring architecture was achieved by combining data from all four muscles. These data show different designs of the hamstring muscles, especially between the SM and ST (medial) and BFlh and BFsh (lateral) muscles. Modeling the hamstrings as one muscle group by assuming uniform inter-muscular architecture yields less accurate representation of human hamstring muscle function. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Ultrasound assessment of hamstring muscle size using posterior thigh muscle thickness.

    Science.gov (United States)

    Abe, Takashi; Loenneke, Jeremy P; Thiebaud, Robert S

    2016-05-01

    Several studies have investigated the relationship between ultrasound-measured muscle thickness (MT) and individual muscle cross-sectional area (CSA) and muscle volume (MV) in extremity and trunk muscles; however, the hamstring muscle has not been studied. The purpose of this study was to examine the relationship between posterior thigh MT by ultrasound and the muscle CSA and MV of the hamstring obtained by magnetic resonance imaging (MRI). Ten young women aged 20-31 had MT measured by ultrasound at three sites on the medial anterior (50% of thigh length; TL) and posterior (50% and 70% of TL) aspects of the thigh. On the same day, a series of continuous muscle CSA along the thigh was measured by MRI. In each slice, the anatomical CSA of the hamstring (biceps femoris, semitendinosus and semimembranosus) and quadriceps muscle was analysed, and the CSAs at 50% and 70% of TL and maximal CSA of the hamstring (CSAmax ) were determined. MV was calculated by multiplying CSA by slice thickness. A significant correlation was observed between posterior 50% MT and 50% hamstring CSA (r = 0·848, P = 0·002) and between posterior 70% MT and 70% hamstring CSA (r = 0·679, P = 0·031). Posterior 50% MT (r = 0·732, P = 0·016) and 50% MTxTL (r = 0·873, P = 0·001) were also correlated to hamstring MV. Anterior:posterior 50% thigh MT ratio was correlated to MV ratio of quadriceps and hamstring muscles (r = 0·803, P = 0·005). Our results suggest that posterior thigh MT reflects hamstring muscle CSA and MV. The anterior:posterior MT ratio may serve as a surrogate for MV ratio of quadriceps and hamstring. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  1. Anterior Cruciate Ligament Reconstruction using Bone Patellar Tendon Bone autograft in ACL deficient Knee

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    Navin Kumar Karn

    2015-12-01

    Full Text Available Background & Objectives: Injury to Anterior Cruciate Ligament (ACL reconstruction has increased because of increased interest in sports. There are various grafts used for reconstruction of ACL, for example, Bone Patellar Tendon Bone, Hamstring etc. The study was conducted to evaluate the results of Bone Patellar Tendon Bone graft used for reconstruction of Anterior Cruciate Ligament.Materials & Methods: 40 patients with chronic ACL deficient knee presenting to Neuro Hospital from July 2011 to June 2013 were included in the study. The patients with intraarticular fracture of knee, severe OA knee, local active or suspected infection and systemic disease that might influence the study results were excluded from the study. Bone patellar tendon bone graft was harvested from ipsilateral knee in all the cases. The patient was followed till 2 year with specified programme of rehabilitation. The pain was assessed using VAS and the function of the knee was assessed using Modified WOMAC knee index.Results: The long term satisfactory results in terms of functional stability, symptom relief and return to preinjury level of activity was seen in 32 cases (80%. Two knees got infected out of which one required arthroscopic debridement. Mean visual analogue scale was 8 and modified WOMAC knee score was 3 at 2 year follow up.Conclusion: Bone patellar tendon bone graft is useful in high demand patients and cost effective option with high patient satisfaction rate for reconstruction of ACL.JCMS Nepal. 2015;11(3:12-15.

  2. Dynamic restraint capacity of the hamstring muscles has important functional implications after anterior cruciate ligament injury and anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Bryant, Adam L; Creaby, Mark W; Newton, Robert U; Steele, Julie R

    2008-12-01

    The purpose of this study was to investigate the relation between knee functionality of anterior cruciate ligament deficient (ACLD) and anterior cruciate ligament reconstruction (ACLR) patients and hamstring antagonist torque generated during resisted knee extension. Cross-sectional. Laboratory based. Male ACLD subjects (n=10) (18-35 y) and 27 matched males who had undergone ACLR (14 patella tendon [PT] grafts and 13 combined semitendinosus/gracilis tendon grafts). Not applicable. Knee functionality was rated (0- to 100-point scale) by using the Cincinnati Knee Rating System. Using electromyography data from the semitendinosus (ST) and biceps femoris muscles, we created a mathematical model to estimate the opposing torque generated by the hamstrings during isokinetic knee extension in 10 degrees intervals from 80 degrees to 10 degrees knee flexion. Pearson product-moment correlations revealed that more functional ACLD subjects generated significantly (Phamstring antagonist torque throughout knee extension. In contrast, more functional PT subjects produced significantly lower hamstring antagonist torque at 80 degrees to 70 degrees knee flexion, whereas no significant associations were found between hamstring antagonist torque and knee functionality for the ST/gracilis tendon subjects. An increased hamstring antagonist torque generated by the more functional ACLD subjects, reflective of increased hamstring contractile force, is thought to represent a protective mechanism to compensate for mechanical instability. The restoration of anterior knee stability through ACLR negates the need for augmented hamstring antagonist torque.

  3. Mechanical Coupling between Muscle-Tendon Units Reduces Peak Stresses

    NARCIS (Netherlands)

    Maas, Huub; Finni, Taija

    2018-01-01

    The presence of mechanical linkages between synergistic muscles and their common tendons may distribute forces among the involved structures. We review studies, using humans and other animals, examining muscle and tendon interactions and discuss the hypothesis that connections between muscle bellies

  4. Proximal hamstring morphology and morphometry in men: an anatomic and MRI investigation.

    Science.gov (United States)

    Storey, R N; Meikle, G R; Stringer, M D; Woodley, S J

    2016-12-01

    The proximal musculo-tendinous junction (MTJ) is a common site of hamstring strain injury but the anatomy of this region is not well defined. A morphometric analysis of the proximal MTJs of biceps femoris long head (BFlh), semitendinosus (ST), and semimembranosus (SM) was undertaken from dissection of 10 thighs from five male cadavers and magnetic resonance imaging of 20 thighs of 10 active young men. The length, volume, and cross-sectional area of the proximal tendon, MTJ and muscle belly, and muscle-tendon interface area were calculated. In both groups, MTJs were reconstructed three-dimensionally. The proximal tendons and MTJs were expansive, particularly within SM and BFlh. Morphology varied between muscles although length measurements within individual muscles were similar in cadavers and young men. Semimembranosus had the longest proximal tendon (cadavers: mean 33.6 ± 2.0 cm; young men: mean 31.7 ± 1.6 cm) and MTJ (>20 cm in both groups) and the greatest muscle-tendon interface area, followed by BFlh and ST. Mean muscle belly volumes were more than three times greater in young men than elderly male cadavers (P hamstring anatomy, an important factor in the pathogenesis of hamstring strain injury. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Predictors and effects of patellofemoral pain following hamstring-tendon ACL reconstruction.

    Science.gov (United States)

    Culvenor, Adam G; Collins, Natalie J; Vicenzino, Bill; Cook, Jill L; Whitehead, Timothy S; Morris, Hayden G; Crossley, Kay M

    2016-07-01

    Patellofemoral pain is a frequent and troublesome complication following anterior cruciate ligament reconstruction (ACLR), irrespective of graft source. Yet, little is known about the factors associated with patellofemoral pain following hamstring-tendon ACLR. Retrospective analysis of potential patellofemoral pain predictors, and cross-sectional analysis of possible patellofemoral pain consequences. Potential predictors (pre-injury patellofemoral pain and activity level, concomitant patellofemoral cartilage damage and meniscectomy, age, sex, and surgical delay) and consequences (hopping performance, quality of life, kinesiophobia, and return to sport rates and attitudes) of patellofemoral pain 12 months following hamstring-tendon ACLR were assessed in 110 participants using univariate and multivariate analyses. Thirty-three participants (30%) had patellofemoral pain at 12 months post-ACLR. Older age at the time of ACLR was the only predictor of post-operative patellofemoral pain. Following ACLR, those with patellofemoral pain had a higher body mass index, and worse physical performance, quality of life, kinesiophobia and return to sport attitudes. Patellofemoral pain has a significant burden on individuals 12 months following hamstring-tendon ACLR. Clinicians need to be cognisant of patellofemoral pain, particularly in older individuals and those with a higher body mass index. The importance of considering psychological factors that are not typically addressed during ACLR rehabilitation, such as kinesiophobia, quality of life and return to sport attitudes is emphasised. Copyright © 2016. Published by Elsevier Ltd.

  6. Anatomic single-bundle anterior cruciate ligament reconstruction improves walking economy: hamstrings tendon versus patellar tendon grafts.

    Science.gov (United States)

    Iliopoulos, Efthymios; Galanis, Nikiforos; Zafeiridis, Andreas; Iosifidis, Michael; Papadopoulos, Pericles; Potoupnis, Michael; Geladas, Nikolaos; Vrabas, Ioannis S; Kirkos, John

    2017-10-01

    Anterior cruciate ligament (ACL) injury is associated with a pathologic gait pattern and increased energy cost during locomotion. ACL reconstruction could improve the gait pattern. Hamstrings tendon (HAM) and bone-patellar tendon-bone (BPTB) grafts are usually used for reconstruction. The aim of this study was to compare the efficacy of anatomic ACL reconstruction with HAM and BPTB grafts on improving and normalizing the energy cost and physiologic reserves during flat, uphill, and downhill walking. Twenty male subjects with unilateral ACL injuries were randomly assigned to ACL reconstruction with a HAM (n = 10) or BPTB (n = 10) graft. Ten matched controls were also enrolled. All participants performed three 8-min walking tasks at 0, +10, and -10 % gradients before and 9 months after surgery. Energy cost (oxygen consumption, VO 2 ), heart rate (HR), and ventilation (VE) were measured. Lysholm/IKDC scores were recorded. Pre-operatively, VO 2 , HR, and VE were higher in the HAM and BPTB groups than in controls during walking at 0, +10, and -10 % gradients (p energy cost and nearly normalized locomotion economy and cardiorespiratory reserves during flat, uphill, and downhill walking. The improved locomotion economy is an additional benefit of anatomic ACL reconstruction, irrespective of the type of graft used, that the orthopaedic surgeons should consider. II.

  7. Tensile strength comparison between peroneus longus and hamstring tendons: A biomechanical study

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    Rudy

    2017-01-01

    Conclusion: The tensile strength of the peroneus longus tendon, which is similar to that of hamstring, gives information that both have the same biomechanic properties. Peroneus longus should not be used as a first option in ACL reconstruction, but may be used as an alternative donor in cases involving multiple instability that require more tendon donors in the reconstruction.

  8. Contractile function and motor unit firing rates of the human hamstrings.

    Science.gov (United States)

    Kirk, Eric A; Rice, Charles L

    2017-01-01

    Neuromuscular properties of the lower limb in health, aging, and disease are well described for major lower limb muscles comprising the quadriceps, triceps surae, and dorsiflexors, with the notable exception of the posterior thigh (hamstrings). The purpose of this study was to further characterize major muscles of the lower limb by comprehensively exploring contractile properties in relation to spinal motor neuron output expressed as motor unit firing rates (MUFRs) in the hamstrings of 11 (26.5 ± 3.8) young men. Maximal isometric voluntary contraction (MVC), voluntary activation, stimulated contractile properties including a force-frequency relationship, and MUFRs from submaximal to maximal voluntary contractile intensities were assessed in the hamstrings. Strength and MUFRs were assessed at two presumably different muscle lengths by varying the knee joint angles (90° and 160°). Knee flexion MVCs were 60-70% greater in the extended position (160°). The frequency required to elicit 50% of maximum tetanic torque was 16-17 Hz. Mean MUFRs at 25-50% MVC were 9-31% less in the biceps femoris compared with the semimembranosus-semitendinosus group. Knee joint angle (muscle length) influenced MUFRs such that mean MUFRs were greater in the shortened (90°) position at 50% and 100% MVC. Compared with previous reports, mean maximal MUFRs in the hamstrings are greater than those in the quadriceps and triceps surae and somewhat less than those in the tibialis anterior. Mean maximal MUFRs in the hamstrings are influenced by changes in knee joint angle, with lower firing rates in the biceps femoris compared with the semimembranosus-semitendinosus muscle group. We studied motor unit firing rates (MUFRs) at various voluntary contraction intensities in the hamstrings, one of the only major lower limb muscles to have MUFRs affected by muscle length changes. Within the hamstrings muscle-specific differences have greater impact on MUFRs than length changes, with the biceps femoris

  9. Comparing Dimensions of Four-Strand Hamstring Tendon Grafts with Native Anterior and Posterior Cruciate Ligaments

    Directory of Open Access Journals (Sweden)

    Barış Yılmaz

    2016-01-01

    Full Text Available Background. The aim of the study was to evaluate whether or not there was any incompatibility between four-strand hamstring tendons taken from the same knee and the dimensions of the ACL and PCL. Methods. 15 fresh frozen cadaver hamstrings were prepared as four-strand grafts and measurements made of the ACL and PCL circumferences in the midsection were made in the narrowest part of the midsection. The cross-section areas and diameters were calculated with geometric calculations used to measure the cross-sectional area of cylinders. Accepting that the geometric insertions were elliptical, the length, width, and area were calculated for entry areas. Results. A significant relationship at 96.2% was determined between the ACL mid and the hamstring diameter. A significant relationship at 96.7% was determined between the ACL and the hamstring mid area. A significant relationship at 96.4% was determined between the PCL mid and the hamstring diameter. A significant relationship at 95.7% was determined between the PCL and the hamstring mid area. Conclusion. For the reconstruction of ACL and PCL, it was determined that there is less incompatibility between the four-strand hamstring tendons taken from the same knee and the dimensions of the midsection PCL compared to the ACL dimensions.

  10. Quadriceps tendon autograft for arthroscopic knee ligament reconstruction: use it now, use it often.

    Science.gov (United States)

    Sheean, Andrew J; Musahl, Volker; Slone, Harris S; Xerogeanes, John W; Milinkovic, Danko; Fink, Christian; Hoser, Christian

    2018-04-28

    Traditional bone-patellar tendon-bone and hamstring tendon ACL grafts are not without limitations. A growing body of anatomic, biomechanical and clinical data has demonstrated the utility of quadriceps tendon autograft in arthroscopic knee ligament reconstruction. The quadriceps tendon autograft provides a robust volume of tissue that can be reliably harvested, mitigating the likelihood of variably sized grafts and obviating the necessity of allograft augmentation. Modern, minimally invasive harvest techniques offer the advantages of low rates of donor site morbidity and residual extensor mechanism strength deficits. New data suggest that quadriceps tendon autograft may possess superior biomechanical characteristics when compared with bone-patella tendon-bone (BPTB) autograft. However, there have been very few direct, prospective comparisons between the clinical outcomes associated with quadriceps tendon autograft and other autograft options (eg, hamstring tendon and bone-patellar tendon-bone). Nevertheless, quadriceps tendon autograft should be one of the primary options in any knee surgeon's armamentarium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Ropivacaine alters the mechanical properties of hamstring tendons: In vitro controlled mechanical testing of tendons from living donors.

    Science.gov (United States)

    Ollivier, M; Sbihi, J; Sbihi, A; Pithioux, M; Parratte, S; Argenson, J-N

    2017-11-01

    Intraarticular or periarticular injection of ropivacaine (RI) is an element of current knee surgery practices. The goal of this study was to determine the effects of RI on the mechanical properties of hamstring tendons. We hypothesized that RI would have a detrimental effect on the mechanical properties of periarticular soft tissues METHODS: A tensile test to failure was performed on 120 hamstring tendon segments harvested during ACL reconstruction surgery in 120 patients. Two sets of tensile tests were done. The first evaluated the effect of RI itself on the mechanical properties of tendons: 30 samples were soaked for 1hour in a 2% RI solution and compared to 30 samples soaked in a saline solution (control group). The second evaluated the effect of RI concentration on the mechanical properties of hamstring tendons: 30 samples were soaked for 1hour in a 2% RI solution and 30 samples were soaked in a 7.5% RI solution. In the first test, 29 samples from each group were analyzed as two samples (one in each group) failed at the grip interface. The specimens exposed to 2% RI had lower ultimate tensile strength (Δ=4.4MPa, P=0.001), strain energy (Δ=13MPa, P=0.001) and Young's modulus (Δ=1.6MPa, P=0.02) than the specimens in the control group. There was no significant difference in the strain at failure between groups (Δ=5%, P=0.3). In the second test, one specimen from the 7.5% RI group failed during the preloading and was excluded. There was no significant difference in terms of the load at failure and ultimate tensile stress (Δ=0.45MPa, P=0.6) and strain energy (Δ=0.49MPa, P=0.49) between the two groups. There were significant differences in terms of elongation at failure (Δ=28%, P=0.0003) and Young's modulus (Δ=2.6MPa, P=0.005), with the specimens exposed to 7.5% RI undergoing greater deformation and having a lower Young's modulus. While local RI injections are widely performed in clinical practice, the results of this in vitro study point to short

  12. Medial Patellofemoral Ligament Reconstruction Using the Hamstring Tendon for Patellofemoral Joint Instability in an 81-Year-Old Female.

    Science.gov (United States)

    Takahashi, Tsuneari; Takeshita, Katsushi

    2017-01-01

    Chronic patellofemoral instability occurs mainly in adolescent females and can also be induced by medial patellofemoral ligament (MPFL) injury. There are no case reports of MPFL reconstruction for chronic patellofemoral instability due to MPFL injury in aged populations. 81-year-old female presented with left knee pain, giving way, and patellar instability while climbing stairs, which continued for 18 months. Patellar apprehension test was positive, and roentgenogram showed lateral patellar subluxation. Conservative therapy was not successful; hence, we performed a lateral release and MPFL reconstruction surgery. After arthroscopic lateral release, the hamstring tendon was harvested, and a graft composite made of doubled hamstring tendon and polyester tape with a suspensory fixation device was prepared. Then, a femoral bone tunnel was constructed in a socket shape at the anatomical footprint of the MPFL. The graft was passed through the femoral tunnel, and free ends of the graft composite were sutured to the periosteum of the patella, using two suture anchors at 60° of knee flexion with patellar reduction. Physiotherapy was gradually started using a patella-stabilizing orthosis on the first postoperative day. Her Kujala score improved from 66 to 97 points, and Barthel index score improved from 70 to 100 points at 1 year after surgery. She neither developed patellofemoral joint OA nor had any recurrence of symptoms at the 5-year postoperative follow up. MPFL reconstruction using the hamstring tendon is an effective procedure for patients with chronic patellofemoral instability even after the age of 80 years.

  13. COMPARATIVE STUDY OF CLINICAL OUTCOME OF ARTHROSCOPIC ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION BONE PATELLAR TENDON BONE GRAFT V/S HAMSTRING GRAFT

    Directory of Open Access Journals (Sweden)

    Priyank

    2015-08-01

    fulfilling the predetermined inclusion and exclusion criteria were included in the study. STATISTICAL METHODS : Intergroup comparison was analysed by K - Independent sample t test. Intragroup comparison was analysed by Paired t - test. RESULTS : Patients were divided into two groups and treated with using Bone - patellar tendon - bone graft and Hamstring graft respectively. Mean age group of patients was 29.16 yrs. (range 16 - 51yrs and 30.88 yrs. (range 19 - 48yrs in group A and B respectively we found the incidence of ACL injury in 15 - 44 years age group to be greater than twice the general population. A mean delay in surgery of 4.66 months (range 2 - 12 months since the time of injury in group A and 4.46 months (range 2 - 7 months in group B was observed. Subjective IKDC evaluation was done at the end of 12 months. Ther e was no difference in both the groups in the terms of effusion, passive motion, knee compartment findings, ligament examination, X - ray findings. Functional test and IKDC grade of both the groups showed statistically very highly significant improvement. Ho wever, there was statistically very high Harvest site pathology in group A. CONCLUSION : We found that there is statistically no significant difference in the overall clinical outcome between hamstring autograft with transfix and bone - patellar tendon bone autograft with interference screw except that the patellar tendon group had a greater tendency of having donor site morbidity compared to the hamstring tendon group.

  14. Outcomes of the patellar tendon and hamstring graft anterior cruciate ligament reconstructions in patients aged above 50 years

    Directory of Open Access Journals (Sweden)

    Tarun Bali

    2015-01-01

    Full Text Available Background: The treatment of anterior cruciate ligament (ACL injury consists of arthroscopic ACL reconstruction with patellar tendon or hamstring graft. Satisfactory results have been reported so far in the younger age group. Dilemma arises regarding the suitability of ACL reconstruction in the patients aged 50 years and above. This retrospective analyses the outcome of ACL reconstruction in patients aged 50 years and above at the time of presentation. Materials and Methods: 55 patients aged 50 years and above presented to our institution with symptomatic ACL tear and were managed with arthroscopic reconstruction with patellar tendon/hamstring graft. 22 patients underwent ACL reconstruction with bone- patellar tendon-bone graft and the remaining 33 with a hamstring graft. Evaluation of functional outcome was performed using International Knee Documentation Committee (IKDC and Lysholm scoring in the preoperative period, at the end of 1 year and at the final followup. Radiographic evaluation was performed using the Kellgren–Lawrence grading system. Results: The mean preoperative IKDC score was 39.7 ± 3.3. At the end of 1-year following the operation, the mean IKDC score was 73.6 ± 4.9 and at the final followup was 67.8 ± 7.7. The mean preoperative Lysholm score was 40.4 ± 10.3. At the end of 1-year following the intervention, the mean Lysholm score was 89.7 ± 2.1 and at final followup was 85.3 ± 2.5. Overall, 14 out of 42 patients who underwent radiographic assessment showed progression of osteoarthritis changes at the final followup after the intervention. Conclusion: In our study, there was a statistically significant improvement in the IKDC and Lysholm scores following the intervention. There was a slight deterioration in the scores at the final followup but the overall rate of satisfaction was still high and most of the patients were able to do their routine chores and light exercises suitable for their age group. Around one-third of

  15. Hip and trunk muscles activity during nordic hamstring exercise.

    Science.gov (United States)

    Narouei, Shideh; Imai, Atsushi; Akuzawa, Hiroshi; Hasebe, Kiyotaka; Kaneoka, Koji

    2018-04-01

    The nordic hamstring exercise (NHE) is a dynamic lengthening hamstring exercise that requires trunk and hip muscles activation. Thigh muscles activation, specifically hamstring/quadriceps contractions has been previously examined during NHE. Trunk and hip muscles activity have not been enough studied. The aim of this study was to analyze of hip and trunk muscles activity during NHE. Surface electromyography (EMG) and kinematic data were collected during NHE. Ten healthy men with the age range of 21-36 years performed two sets of two repetitions with downward and upward motions each of NHE. EMG activity of fifteen trunk and hip muscles and knee kinematic data were collected. Muscle activity levels were calculated through repeated measure analysis of variance in downward and upward motions, through Paired t -test between downward and upward motions and gluteus maximus to erector spine activity ratio (Gmax/ES ratio) using Pearson correlation analyses were evaluated. Semitendinosus and biceps femoris muscles activity levels were the greatest in both motions and back extensors and internal oblique muscles activity were greater than other muscles ( P hamstrings contractions. It could be important for early assessment of subjects with hamstring injury risk.

  16. Fetal development of the pulley for muscle insertion tendons: A review and new findings related to the tensor tympani tendon.

    Science.gov (United States)

    Rodríguez-Vázquez, Jose Francisco; Honkura, Yohei; Katori, Yukio; Murakami, Gen; Abe, Hiroshi

    2017-01-01

    The existence of hard tissue pulleys that act to change the direction of a muscle insertion tendon is well known in the human body. These include (1) the trochlea for the extraocular obliquus superior muscle, (2) the pterygoid hamulus for the tensor veli palatini muscle, (3) the deep sulcus on the plantar aspect of the cuboid bone for the peroneus longus tendon, (4) the lesser sciatic notch for the obturator internus muscle, and (5) the bony trochleariformis process for the tensor tympani muscle tendon. In addition, (6) the stapedius muscle tendon shows a lesser or greater angulation at the pyramidal eminence of the temporal bone. Our recent studies have shown that the development of pulleys Nos. 1 and 2 can be explained by a change in the topographical relationship between the pulley and the tendon, that of pulley No. 3 by the rapidly growing calcaneus pushing the tendon, and that of pulley No. 4 by migration of the insertion along the sciatic nerve and gluteus medius tendon. Therefore, in Nos. 1-4, an initially direct tendon curves secondarily and obtains an attachment to the pulley. In case No. 6, the terminal part of the stapedius tendon originates secondarily from the interzone mesenchymal tissue of the incudostapedial joint. In the case of pulley No. 5, we newly demonstrated that its initial phase of development was similar to No. 6, but the tensor tympani tendon achieved a right-angled turn under guidance by a specific fibrous tissue and it migrated along the growing malleus manubrium. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Elastography Study of Hamstring Behaviors during Passive Stretching.

    Directory of Open Access Journals (Sweden)

    Guillaume Le Sant

    Full Text Available The mechanical properties of hamstring muscles are usually inferred from global passive torque/angle relationships, in combination with adjoining tissues crossing the joint investigated. Shear modulus measurement provides an estimate of changes in muscle-tendon stiffness and passive tension. This study aimed to assess the passive individual behavior of each hamstring muscle in different stretching positions using shear wave elastography.The muscle shear modulus of each hamstring muscle was measured during a standardized slow passive knee extension (PKE, 80% of maximal range of motion on eighteen healthy male volunteers. Firstly, we assessed the reliability of the measurements. Results were good for semitendinosus (ST, CV: 8.9%-13.4%, semimembranosus (SM, CV: 10.3%-11.2% and biceps femoris long-head (BF-lh, CV: 8.6%-13.3%, but not for biceps femoris short-head (BF-sh, CV: 20.3%-44.9%. Secondly, we investigated each reliable muscle in three stretch positions: 70°, 90° and 110° of hip flexion. The results showed different values of shear modulus for the same amount of perceived stretch, with the highest measurements in the high-flexed hip situation. Moreover, individual muscles displayed different values, with values increasing or BF-lh, SM and ST, respectively. The inter-subject variability was 35.3% for ST, 27.4% for SM and 30.2% for BF-lh.This study showed that the hip needs to be high-flexed to efficiently tension the hamstrings, and reports a higher muscle-tendon stress tolerance at 110° of hip angle. In addition muscles have different passive behaviors, and future works will clarify if it can be linked with rate of injury.

  18. Elastography Study of Hamstring Behaviors during Passive Stretching

    Science.gov (United States)

    Le Sant, Guillaume; Ates, Filiz; Brasseur, Jean-Louis; Nordez, Antoine

    2015-01-01

    Introduction The mechanical properties of hamstring muscles are usually inferred from global passive torque/angle relationships, in combination with adjoining tissues crossing the joint investigated. Shear modulus measurement provides an estimate of changes in muscle-tendon stiffness and passive tension. This study aimed to assess the passive individual behavior of each hamstring muscle in different stretching positions using shear wave elastography. Methods/Results The muscle shear modulus of each hamstring muscle was measured during a standardized slow passive knee extension (PKE, 80% of maximal range of motion) on eighteen healthy male volunteers. Firstly, we assessed the reliability of the measurements. Results were good for semitendinosus (ST, CV: 8.9%-13.4%), semimembranosus (SM, CV: 10.3%-11.2%) and biceps femoris long-head (BF-lh, CV: 8.6%-13.3%), but not for biceps femoris short-head (BF-sh, CV: 20.3%-44.9%). Secondly, we investigated each reliable muscle in three stretch positions: 70°, 90° and 110° of hip flexion. The results showed different values of shear modulus for the same amount of perceived stretch, with the highest measurements in the high-flexed hip situation. Moreover, individual muscles displayed different values, with values increasing or BF-lh, SM and ST, respectively. The inter-subject variability was 35.3% for ST, 27.4% for SM and 30.2% for BF-lh. Conclusion This study showed that the hip needs to be high-flexed to efficiently tension the hamstrings, and reports a higher muscle-tendon stress tolerance at 110° of hip angle. In addition muscles have different passive behaviors, and future works will clarify if it can be linked with rate of injury. PMID:26418862

  19. A RETROSPECTIVE ANALYSIS OF ARTHROSCOPIC ACL RECONSTRUCTION WITH HAMSTRING TENDON GRAFT

    Directory of Open Access Journals (Sweden)

    Ashish R. Agarwal

    2017-08-01

    Full Text Available BACKGROUND ACL reconstruction is one of the commonest knee surgeries done. Young adults are the commonest patients; thus, this injury has a large impact on socioeconomic status of the family. The aim of the study is to study the outcome of arthroscopic ACL reconstruction with hamstring tendon graft. MATERIALS AND METHODS 50 patients following up in the OPD who had undergone ACL reconstruction with hamstring tendon graft are evaluated. Patients who had other lesions, such meniscal injuries or collateral injuries were discarded. These patients were evaluated by using Tegner and Lysholm score of 6 months, 12 months and 24 months. Settings- It is a retrospective analysis of the data collected from the patients who were opiated at Nair Hospital. RESULTS 90% of patients in the study were males. Mean age of the study population is 30.7 years. All the patients in the study had instability as a symptom, while 80% of them also had pain. Six months after surgery, according to Tegner and Lysholm score, 52% patients had good outcome, while 48% had fair outcome. At 2 years, 98% of study population had excellent outcome. CONCLUSION Arthroscopic ACL reconstruction with hamstring graft is an effective way of treating ACL tear.

  20. Different Muscle Action Training Protocols on Quadriceps-Hamstrings Neuromuscular Adaptations.

    Science.gov (United States)

    Ruas, Cassio V; Brown, Lee E; Lima, Camila D; Gregory Haff, G; Pinto, Ronei S

    2018-05-01

    The aim of this study was to compare three specific concentric and eccentric muscle action training protocols on quadriceps-hamstrings neuromuscular adaptations. Forty male volunteers performed 6 weeks of training (two sessions/week) of their dominant and non-dominant legs on an isokinetic dynamometer. They were randomly assigned to one of four groups; concentric quadriceps and concentric hamstrings (CON/CON, n=10), eccentric quadriceps and eccentric hamstrings (ECC/ECC, n=10), concentric quadriceps and eccentric hamstrings (CON/ECC, n=10), or no training (CTRL, n=10). Intensity of training was increased every week by decreasing the angular velocity for concentric and increasing it for eccentric groups in 30°/s increments. Volume of training was increased by adding one set every week. Dominant leg quadriceps and hamstrings muscle thickness, muscle quality, muscle activation, muscle coactivation, and electromechanical delay were tested before and after training. Results revealed that all training groups similarly increased MT of quadriceps and hamstrings compared to control (p0.05). These findings suggest that different short-term muscle action isokinetic training protocols elicit similar muscle size increases in hamstrings and quadriceps, but not for other neuromuscular variables. Nevertheless, effect sizes indicate that CON/ECC and ECC/ECC may elicit the greatest magnitude of change in muscle hypertrophy. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Isokinetic hamstring and quadriceps muscle strength profiles of elite ...

    African Journals Online (AJOL)

    Football players are at risk of lower limb injuries, specifically hamstring muscle strains and ACL injuries due to muscle imbalances. This was a descriptive study assessing the isokinetic hamstring and quadriceps muscle strength and endurance in 28 elite, male, South African football players. Muscle strength was tested at 60 ...

  2. Flexion relaxation of the hamstring muscles during lumbar-pelvic rhythm.

    Science.gov (United States)

    Sihvonen, T

    1997-05-01

    This study investigated the simultaneous activity of back muscles and hamstring muscles during sagittal forward body flexion and extension in healthy persons. The study was cross-sectional. A descriptive study of paraspinal and hamstring muscle activity in normal persons during lumbar-pelvic rhythm. A university hospital. Forty healthy volunteers (21 men, 19 women, ages 17 to 48 years), all without back pain or other pain syndromes. Surface electromyography (EMG) was used to follow activities in the back and the hamstring muscles. With movement sensors, real lumbar flexion was separated from simultaneous pelvic motion by monitoring the components of motion with a two-inclinometer method continuously from the initial upright posture into full flexion. All signals were sampled during real-time monitoring for off-line analyses. Back muscle activity ceased (ie, flexion relaxation [FR] occurred) at lumbar flexion with a mean of 79 degrees. Hamstring activity lasted longer and EMG activity ceased in the hamstrings when nearly full lumbar flexion (97%) was reached. After this point total flexion and pelvic flexion continued further, so that the last part of lumbar flexion and the last part of pelvic flexion happened without back muscle activity or hamstring bracing, respectively. FR of the back muscles during body flexion has been well established and its clinical significance in low back pain has been confirmed. In this study, it was shown for the first time that the hip extensors (ie, hamstring muscles) relax during forward flexion but with different timing. FR in hamstrings is not dependent on or coupled firmly with back muscle behavior in spinal disorders and the lumbar pelvic rhythm can be locally and only partially disturbed.

  3. MR observations of long-term musculotendon remodeling following a hamstring strain injury

    International Nuclear Information System (INIS)

    Silder, Amy; Heiderscheit, Bryan C.; Thelen, Darryl G.; Enright, Timothy; Tuite, Michael J.

    2008-01-01

    The objective of this study was to use magnetic resonance (MR) imaging to investigate long-term changes in muscle and tendon morphology following a hamstring strain injury. MR images were obtained from 14 athletes who sustained a clinically diagnosed grade I-II hamstring strain injury between 5 and 23 months prior as well as five healthy controls. Qualitative bilateral comparisons were used to assess the presence of fatty infiltration and changes in morphology that may have arisen as a result of the previous injury. Hamstring muscle and tendon-scar volumes were quantified in both limbs for the biceps femoris long head (BFLH), biceps femoris short head (BFSH), the proximal semimembranosus tendon, and the proximal conjoint biceps femoris and semitendinosus tendon. Differences in muscle and tendon volume between limbs were statistically compared between the previously injured and healthy control subjects. Increased low-intensity signal was present along the musculotendon junction adjacent to the site of presumed prior injury for 11 of the 14 subjects, suggestive of persistent scar tissue. The 13 subjects with biceps femoris injuries displayed a significant decrease in BFLH volume (p < 0.01), often accompanied by an increase in BFSH volume. Two of these subjects also presented with fatty infiltration within the previously injured BFLH. The results of this study provide evidence of long-term musculotendon remodeling following a hamstring strain injury. Additionally, many athletes are likely returning to sport with residual atrophy of the BFLH and/or hypertrophy of the BFSH. It is possible that long-term changes in musculotendon structure following injury alters contraction mechanics during functional movement, such as running and may contribute to reinjury risk. (orig.)

  4. MR observations of long-term musculotendon remodeling following a hamstring strain injury

    Energy Technology Data Exchange (ETDEWEB)

    Silder, Amy [University of Wisconsin, Madison, WI (US). Department of Biomedical Engineering, Madison, WI (United States); Heiderscheit, Bryan C. [University of Wisconsin, Madison, WI (US). Department of Biomedical Engineering, Madison, WI (United States); University of Wisconsin, Madison, WI (US). Department of Orthopedics and Rehabilitation, Madison, WI (United States); Thelen, Darryl G. [University of Wisconsin, Madison, WI (US). Department of Biomedical Engineering, Madison, WI (United States); University of Wisconsin, Madison, WI (US). Department of Orthopedics and Rehabilitation, Madison, WI (United States); University of Wisconsin, Madison, WI (US). Department of Mechanical Engineering, Madison, WI (United States); Enright, Timothy; Tuite, Michael J. [University of Wisconsin, Madison, WI (United States). Department of Radiology

    2008-12-15

    The objective of this study was to use magnetic resonance (MR) imaging to investigate long-term changes in muscle and tendon morphology following a hamstring strain injury. MR images were obtained from 14 athletes who sustained a clinically diagnosed grade I-II hamstring strain injury between 5 and 23 months prior as well as five healthy controls. Qualitative bilateral comparisons were used to assess the presence of fatty infiltration and changes in morphology that may have arisen as a result of the previous injury. Hamstring muscle and tendon-scar volumes were quantified in both limbs for the biceps femoris long head (BFLH), biceps femoris short head (BFSH), the proximal semimembranosus tendon, and the proximal conjoint biceps femoris and semitendinosus tendon. Differences in muscle and tendon volume between limbs were statistically compared between the previously injured and healthy control subjects. Increased low-intensity signal was present along the musculotendon junction adjacent to the site of presumed prior injury for 11 of the 14 subjects, suggestive of persistent scar tissue. The 13 subjects with biceps femoris injuries displayed a significant decrease in BFLH volume (p < 0.01), often accompanied by an increase in BFSH volume. Two of these subjects also presented with fatty infiltration within the previously injured BFLH. The results of this study provide evidence of long-term musculotendon remodeling following a hamstring strain injury. Additionally, many athletes are likely returning to sport with residual atrophy of the BFLH and/or hypertrophy of the BFSH. It is possible that long-term changes in musculotendon structure following injury alters contraction mechanics during functional movement, such as running and may contribute to reinjury risk. (orig.)

  5. Comparison of a novel bone-tendon allograft with a human dermis-derived patch for repair of chronic large rotator cuff tears using a canine model.

    Science.gov (United States)

    Smith, Matthew J; Cook, James L; Kuroki, Keiichi; Jayabalan, Prakash S; Cook, Cristi R; Pfeiffer, Ferris M; Waters, Nicole P

    2012-02-01

    This study tested a bone-tendon allograft versus human dermis patch for reconstructing chronic rotator cuff repair by use of a canine model. Mature research dogs (N = 15) were used. Radiopaque wire was placed in the infraspinatus tendon (IST) before its transection. Three weeks later, radiographs showed IST retraction. Each dog then underwent 1 IST treatment: debridement (D), direct repair of IST to bone with a suture bridge and human dermis patch augmentation (GJ), or bone-tendon allograft (BT) reconstruction. Outcome measures included lameness grading, radiographs, and ultrasonographic assessment. Dogs were killed 6 months after surgery and both shoulders assessed biomechanically and histologically. BT dogs were significantly (P = .01) less lame than the other groups. BT dogs had superior bone-tendon, tendon, and tendon-muscle integrity compared with D and GJ dogs. Biomechanical testing showed that the D group had significantly (P = .05) more elongation than the other groups whereas BT had stiffness and elongation characteristics that most closely matched normal controls. Radiographically, D and GJ dogs showed significantly more retraction than BT dogs (P = .003 and P = .045, respectively) Histologically, GJ dogs had lymphoplasmacytic infiltrates, tendon degeneration and hypocellularity, and poor tendon-bone integration. BT dogs showed complete incorporation of allograft bone into host bone, normal bone-tendon junctions, and well-integrated allograft tendon. The bone-tendon allograft technique re-establishes a functional IST bone-tendon-muscle unit and maintains integrity of repair in this model. Clinical trials using this bone-tendon allograft technique are warranted. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. Association between maximal hamstring strength and hamstring muscle pre-activity during a movement associated with non-contact ACL injury

    DEFF Research Database (Denmark)

    Skov Husted, Rasmus; Bencke, Jesper; Thorborg, Kristian

    2014-01-01

    Introduction Reduced hamstring pre-activity during side-cutting may predispose for non-contact ACL injury. During the last decade resistance training of the lower limb muscles has become an integral part of ACL injury prevention in e.g. soccer and handball. However, it is not known whether a strong...... hamstring (ACL-agonist) musculature is associated with a high level of hamstring muscle pre-activity during high risk movements such as side-cutting. The purpose of this study was to examine the relationship between hamstring muscle pre-activity recorded during a standardized sidecutting maneuver...... translate into high levels of muscle pre-activity during movements like the sidecutting maneuver. Thus, other exercise modalities (i.e. neuromuscular training) are needed to optimize hamstring muscle pre-activity during movements associated with non-contact ACL injury....

  7. Hip and trunk muscles activity during nordic hamstring exercise

    Science.gov (United States)

    Narouei, Shideh; Imai, Atsushi; Akuzawa, Hiroshi; Hasebe, Kiyotaka; Kaneoka, Koji

    2018-01-01

    The nordic hamstring exercise (NHE) is a dynamic lengthening hamstring exercise that requires trunk and hip muscles activation. Thigh muscles activation, specifically hamstring/quadriceps contractions has been previously examined during NHE. Trunk and hip muscles activity have not been enough studied. The aim of this study was to analyze of hip and trunk muscles activity during NHE. Surface electromyography (EMG) and kinematic data were collected during NHE. Ten healthy men with the age range of 21–36 years performed two sets of two repetitions with downward and upward motions each of NHE. EMG activity of fifteen trunk and hip muscles and knee kinematic data were collected. Muscle activity levels were calculated through repeated measure analysis of variance in downward and upward motions, through Paired t-test between downward and upward motions and gluteus maximus to erector spine activity ratio (Gmax/ES ratio) using Pearson correlation analyses were evaluated. Semitendinosus and biceps femoris muscles activity levels were the greatest in both motions and back extensors and internal oblique muscles activity were greater than other muscles (Phamstrings contractions. It could be important for early assessment of subjects with hamstring injury risk. PMID:29740557

  8. Hamstring Muscle Injuries, a Rehabilitation Protocol Purpose.

    Science.gov (United States)

    Valle, Xavier; L Tol, Johannes; Hamilton, Bruce; Rodas, Gil; Malliaras, Peter; Malliaropoulos, Nikos; Rizo, Vicenc; Moreno, Marcel; Jardi, Jaume

    2015-12-01

    Hamstring acute muscle injuries are prevalent in several sports including AFL football (Australian Football League), sprinting and soccer, and are often associated with prolonged time away from sport. In response to this, research into prevention and management of hamstring injury has increased, but epidemiological data shows no decline in injury and re-injury rates, suggesting that rehabilitation programs and return to play (RTP) criteria have to be improved. There continues to be a lack of consensus regarding how to assess performance, recovery and readiness to RTP, following hamstring strain injury. The aim of this paper was to propose rehabilitation protocol for hamstring muscle injuries based on current basic science and research knowledge regarding injury demographics and management options. Criteria-based (subjective and objective) progression through the rehabilitation program will be outlined along with exercises for each phase, from initial injury to RTP.

  9. Botulinum Neurotoxin A Injections Influence Stretching of the Gastrocnemius Muscle-Tendon Unit in an Animal Model

    Directory of Open Access Journals (Sweden)

    Christopher J. Tuohy

    2012-08-01

    Full Text Available Botulinum Neurotoxin A (BoNT-A injections have been used for the treatment of muscle contractures and spasticity. This study assessed the influence of (BoNT-A injections on passive biomechanical properties of the muscle-tendon unit. Mouse gastrocnemius muscle (GC was injected with BoNT-A (n = 18 or normal saline (n = 18 and passive, non-destructive, in vivo load relaxation experimentation was performed to examine how the muscle-tendon unit behaves after chemical denervation with BoNT-A. Injection of BoNT-A impaired passive muscle recovery (15% vs. 35% recovery to pre-stretching baseline, p < 0.05 and decreased GC stiffness (0.531 ± 0.061 N/mm vs. 0.780 ± 0.037 N/mm, p < 0.05 compared to saline controls. The successful use of BoNT-A injections as an adjunct to physical therapy may be in part attributed to the disruption of the stretch reflex; thereby modulating in vivo passive muscle properties. However, it is also possible that BoNT-A injection may alter the structure of skeletal muscle; thus modulating the in vivo passive biomechanical properties of the muscle-tendon unit.

  10. Architecture and functional ecology of the human gastrocnemius muscle-tendon unit.

    Science.gov (United States)

    Butler, Erin E; Dominy, Nathaniel J

    2016-04-01

    The gastrocnemius muscle-tendon unit (MTU) is central to human locomotion. Structural variation in the human gastrocnemius MTU is predicted to affect the efficiency of locomotion, a concept most often explored in the context of performance activities. For example, stiffness of the Achilles tendon varies among individuals with different histories of competitive running. Such a finding highlights the functional variation of individuals and raises the possibility of similar variation between populations, perhaps in response to specific ecological or environmental demands. Researchers often assume minimal variation in human populations, or that industrialized populations represent the human species as well as any other. Yet rainforest hunter-gatherers, which often express the human pygmy phenotype, contradict such assumptions. Indeed, the human pygmy phenotype is a potential model system for exploring the range of ecomorphological variation in the architecture of human hindlimb muscles, a concept we review here. © 2015 Anatomical Society.

  11. The effect of Nordic hamstring strength training on muscle architecture, stiffness, and strength.

    Science.gov (United States)

    Seymore, Kayla D; Domire, Zachary J; DeVita, Paul; Rider, Patrick M; Kulas, Anthony S

    2017-05-01

    Hamstring strain injury is a frequent and serious injury in competitive and recreational sports. While Nordic hamstring (NH) eccentric strength training is an effective hamstring injury-prevention method, the protective mechanism of this exercise is not understood. Strength training increases muscle strength, but also alters muscle architecture and stiffness; all three factors may be associated with reducing muscle injuries. The purpose of this study was to examine the effects of NH eccentric strength training on hamstring muscle architecture, stiffness, and strength. Twenty healthy participants were randomly assigned to an eccentric training group or control group. Control participants performed static stretching, while experimental participants performed static stretching and NH training for 6 weeks. Pre- and post-intervention measurements included: hamstring muscle architecture and stiffness using ultrasound imaging and elastography, and maximal hamstring strength measured on a dynamometer. The experimental group, but not the control group, increased volume (131.5 vs. 145.2 cm 3 , p hamstring strength. The NH intervention was an effective training method for muscle hypertrophy, but, contrary to common literature findings for other modes of eccentric training, did not increase fascicle length. The data suggest that the mechanism behind NH eccentric strength training mitigating hamstring injury risk could be increasing volume rather than increasing muscle length. Future research is, therefore, warranted to determine if muscle hypertrophy induced by NH training lowers future hamstring strain injury risk.

  12. Tendon Transfer Surgery

    Science.gov (United States)

    ... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is ... Hand Therapist? Media Find a Hand Surgeon Home Anatomy ... DESCRIPTION The tendon is the strong cord at either end of a muscle that is attached to bone. Tendons , combined with ...

  13. Mechanics of the human hamstring muscles during sprinting.

    Science.gov (United States)

    Schache, Anthony G; Dorn, Tim W; Blanch, Peter D; Brown, Nicholas A T; Pandy, Marcus G

    2012-04-01

    An understanding of hamstring mechanics during sprinting is important for elucidating why these muscles are so vulnerable to acute strain-type injury. The purpose of this study was twofold: first, to quantify the biomechanical load (specifically, musculotendon strain, velocity, force, power, and work) experienced by the hamstrings across a full stride cycle; and second, to determine how these parameters differ for each hamstring muscle (i.e., semimembranosus (SM), semitendinosus (ST), biceps femoris long head (BF), biceps femoris short head (BF)). Full-body kinematics and ground reaction force data were recorded simultaneously from seven subjects while sprinting on an indoor running track. Experimental data were integrated with a three-dimensional musculoskeletal computer model comprised of 12 body segments and 92 musculotendon structures. The model was used in conjunction with an optimization algorithm to calculate musculotendon strain, velocity, force, power, and work for the hamstrings. SM, ST, and BF all reached peak strain, produced peak force, and formed much negative work (energy absorption) during terminal swing. The biomechanical load differed for each hamstring muscle: BF exhibited the largest peak strain, ST displayed the greatest lengthening velocity, and SM produced the highest peak force, absorbed and generated the most power, and performed the largest amount of positive and negative work. As peak musculotendon force and strain for BF, ST, and SM occurred around the same time during terminal swing, it is suggested that this period in the stride cycle may be when the biarticular hamstrings are at greatest injury risk. On this basis, hamstring injury prevention or rehabilitation programs should preferentially target strengthening exercises that involve eccentric contractions performed with high loads at longer musculotendon lengths.

  14. The functional significance of hamstrings composition: is it really a "fast" muscle group?

    Science.gov (United States)

    Evangelidis, Pavlos E; Massey, Garry J; Ferguson, Richard A; Wheeler, Patrick C; Pain, Matthew T G; Folland, Jonathan P

    2017-11-01

    Hamstrings muscle fiber composition may be predominantly fast-twitch and could explain the high incidence of hamstrings strain injuries. However, hamstrings muscle composition in vivo, and its influence on knee flexor muscle function, remains unknown. We investigated biceps femoris long head (BFlh) myosin heavy chain (MHC) composition from biopsy samples, and the association of hamstrings composition and hamstrings muscle volume (using MRI) with knee flexor maximal and explosive strength. Thirty-one young men performed maximal (concentric, eccentric, isometric) and explosive (isometric) contractions. BFlh exhibited a balanced MHC distribution [mean ± SD (min-max); 47.1 ± 9.1% (32.6-71.0%) MHC-I, 35.5 ± 8.5% (21.5-60.0%) MHC-IIA, 17.4 ± 9.1% (0.0-30.9%) MHC-IIX]. Muscle volume was correlated with knee flexor maximal strength at all velocities and contraction modes (r = 0.62-0.76, P hamstrings strain injury. Hamstrings muscle volume explained 38-58% of the inter-individual differences in knee flexor maximum strength at a range of velocities and contraction modes, while BFlh muscle composition was not associated with maximal or explosive strength. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Involvement of the Interosseous and Lumbrical Muscle-Tendon Units in the Lateral and Spiral Cords in Dupuytren's Disease of the Middle Fingers.

    Science.gov (United States)

    Thoma, Achilleas; Karpinski, Marta

    2017-07-01

    The nature of intrinsic muscle involvement in Dupuytren's disease of the middle fingers (long and ring) remains poorly characterized. Over the years, the authors have observed that both the spiral and lateral digital cords in the middle fingers receive contribution from intrinsic muscle-tendon units. This report describes the anatomical characteristics and frequency of intrinsic muscle-tendon unit involvement in Dupuytren's disease of the middle fingers. Intrinsic muscle involvement in the middle digits was recorded in the operative reports of patients undergoing Dupuytren's surgery between October of 2013 and February of 2016. The anatomical variations of diseased fascia were delineated and classified. Of the 113 digits with Dupuytren's contracture operated on during this period, 52 involved the middle fingers (12 long and 40 ring fingers). Intrinsic muscles were found to be involved in the contracture of 14 of these digits. Two unique contracture patterns were identified: type I contracture, which involves a lateral digital cord originating from intrinsic muscle-tendon units and contracting only the proximal interphalangeal joint; and type II contracture, which involves a spiral cord receiving contribution from intrinsic muscle-tendon units and contracting both the metacarpophalangeal and proximal interphalangeal joints. The frequency of type I and type II contractures was 6 percent and 12 percent, respectively. Intrinsic hand muscles may contribute to Dupuytren's disease in the middle digits, and the authors suggest resecting cords as close as possible to their musculotendinous origin to improve postoperative outcomes.

  16. Muscle activation patterns in the Nordic hamstring exercise: Impact of prior strain injury.

    Science.gov (United States)

    Bourne, M N; Opar, D A; Williams, M D; Al Najjar, A; Shield, A J

    2016-06-01

    This study aimed to determine: (a) the spatial patterns of hamstring activation during the Nordic hamstring exercise (NHE); (b) whether previously injured hamstrings display activation deficits during the NHE; and (c) whether previously injured hamstrings exhibit altered cross-sectional area (CSA). Ten healthy, recreationally active men with a history of unilateral hamstring strain injury underwent functional magnetic resonance imaging of their thighs before and after six sets of 10 repetitions of the NHE. Transverse (T2) relaxation times of all hamstring muscles [biceps femoris long head (BFlh); biceps femoris short head (BFsh); semitendinosus (ST); semimembranosus (SM)] were measured at rest and immediately after the NHE and CSA was measured at rest. For the uninjured limb, the ST's percentage increase in T2 with exercise was 16.8%, 15.8%, and 20.2% greater than the increases exhibited by the BFlh, BFsh, and SM, respectively (P hamstring muscles (n = 10) displayed significantly smaller increases in T2 post-exercise than the homonymous muscles in the uninjured contralateral limb (mean difference -7.2%, P = 0.001). No muscles displayed significant between-limb differences in CSA. During the NHE, the ST is preferentially activated and previously injured hamstring muscles display chronic activation deficits compared with uninjured contralateral muscles. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Hamstring Muscle Use in Females During Hip-Extension and the Nordic Hamstring Exercise: An fMRI Study.

    Science.gov (United States)

    Messer, Daniel J; Bourne, Matthew N; Williams, Morgan D; Al Najjar, Aiman; Shield, Anthony J

    2018-04-23

    Study Design Cross-sectional study. Background Understanding hamstring muscle activation patterns in resistance training exercises may have implications for the design of strength training and injury prevention programs. Unfortunately, surface electromyography studies have reported conflicting results with regard to hamstring muscle activation patterns in women. Objectives To determine the spatial patterns of hamstring muscle activity during the 45º hip-extension and Nordic hamstring exercises, in females using functional magnetic resonance imaging. Methods Six recreationally active females with no history of lower limb injury underwent functional magnetic resonance imaging (fMRI) on both thighs before and immediately after 5 sets of 6 bilateral eccentric contractions of the 45º hip-extension or Nordic exercises. Using fMRI, the transverse (T2) relaxation times were measured from pre- and post- exercise scans and the percentage increase in T2 was used as an index of muscle activation. Results fMRI revealed a significantly higher biceps femoris long head (BF LongHead ) to semitendinosus ratio during the 45° hip-extension than the Nordic exercise (P = .028). The T2 increase after 45° hip-extension was greater for BF LongHead (P Nordic exercise, the T2 increase for semitendinosus was greater than that of BF ShortHead (P Nordic exercise preferentially recruits that muscle while the hip extension more evenly activates all of the biarticular hamstrings. J Orthop Sports Phys Ther, Epub 23 Apr 2018. doi:10.2519/jospt.2018.7748.

  18. Vibration sensitivity of human muscle spindles and Golgi tendon organs.

    Science.gov (United States)

    Fallon, James B; Macefield, Vaughan G

    2007-07-01

    The responses of the various muscle receptors to vibration are more complicated than a naïve categorization into stretch (muscle spindle primary ending), length (muscle spindle secondary endings), and tension (Golgi tendon organs) receptors. To emphasize the similarity of responses to small length changes, we recorded from 58 individual muscle afferents subserving receptors in the ankle or toe dorsiflexors of awake human subjects (32 primary endings, 20 secondary endings, and six Golgi tendon organs). Transverse sinusoidal vibration was applied to the distal tendon of the receptor-bearing muscle, while subjects either remained completely relaxed or maintained a weak isometric contraction of the appropriate muscle. In relaxed muscle, few units responded in a 1:1 manner to vibration, and there was no evidence of a preferred frequency of activation. In active muscle the response profiles of all three receptor types overlapped, with no significant difference in threshold between receptor types. These results emphasize that when intramuscular tension increases during a voluntary contraction, Golgi tendon organs and muscle spindle secondary endings, not just muscle spindle primary endings, can effectively encode small imposed length changes.

  19. Extracellular matrix adaptation of tendon and skeletal muscle to exercise

    DEFF Research Database (Denmark)

    Kjaer, Michael; Magnusson, Peter; Krogsgaard, Michael

    2006-01-01

    The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotease......-beta and IL-6 is enhanced following exercise. For tendons, metabolic activity (e.g. detected by positron emission tomography scanning), circulatory responses (e.g. as measured by near-infrared spectroscopy and dye dilution) and collagen turnover are markedly increased after exercise. Tendon blood flow...... is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis...

  20. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats

    Science.gov (United States)

    Cury, Diego Pulzatto; Dias, Fernando José; Miglino, Maria Angélica; Watanabe, Ii-sei

    2016-01-01

    Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis. PMID:27078690

  1. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats.

    Directory of Open Access Journals (Sweden)

    Diego Pulzatto Cury

    Full Text Available Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis.

  2. EFFECT OF MUSCLE ENERGY TECHNIQUE ON FLEXIBILITY OF HAMSTRING AND CALF MUSCLES AND SPRINTING PERFORMANCE IN SPRINTERS

    Directory of Open Access Journals (Sweden)

    M. Prasad Naik

    2015-10-01

    Full Text Available Background: Muscle energy technique is used for restoring normal tone in hypertonic muscles, strengthening weak muscles, preparing muscle for subsequent stretching, one of the main uses of this method is to normalize joint range which may help in increase flexibility and performance in sprinters. The aim of the study is to evaluate the effect of muscle energy technique on flexibility of hamstrings and calf muscles and sprinting performance in sprinters. The objective of the study is to determine the muscle energy technique on hamstrings and calf muscle flexibility and sprinting performance in sprinters by using goniometer and timing of sprinting performance. Method: The study design is an experimental study in which 30 male sprinters were recruited in this study. The study sample included all male healthy sprinters, aged between 15 -30 years. All subjects received warm up, muscle energy technique and cool down exercises daily for a period of 6weeks.The outcome measures are 90°-90°popliteal angle for assessing hamstring flexibility and ROM of ankle joint for calf muscles by universal goniometer and sprinting performance time by using stopwatch. Results: Independent t-test and paired t- test are used to analyse the data. A significant difference was found between pre and post values of hamstring and calf muscle flexibility and sprinting performance after the analysis in this study. Conclusion: This study shows that there was a significant effect of MET on hamstring and calf muscle flexibility and sprinting performance.

  3. Self-Mobilization Using a Foam Roller Versus a Roller Massager: Which Is More Effective for Increasing Hamstrings Flexibility?

    Science.gov (United States)

    DeBruyne, Danielle M; Dewhurst, Marina M; Fischer, Katelyn M; Wojtanowski, Michael S; Durall, Chris

    2017-01-01

    Clinical Scenario: Increasing the length of the muscle-tendon unit may prevent musculotendinous injury. Various methods have been proposed to increase muscle-tendon flexibility, including self-mobilization using foam rollers or roller massagers, although the effectiveness of these devices is uncertain. This review was conducted to determine if the use of foam rollers or roller massagers to improve hamstrings flexibility is supported by moderate- to high-quality evidence. Are foam rollers or roller massagers effective for increasing hamstrings flexibility in asymptomatic physically active adults? Summary of Key Findings: The literature was searched for studies on the effects of using foam rollers or roller massagers to increase hamstrings flexibility in asymptomatic physically active adults. Four randomized controlled trials were included; 2 studies provided level 2 or 3 evidence regarding foam rollers and 2 studies provided level 2 or 3 evidence regarding roller massagers. Both roller-massager studies reported increases in hamstrings flexibility after treatment. Data from the foam-roller studies did not demonstrate a statistically significant increase in hamstrings flexibility, but 1 study did demonstrate a strong effect size. Clinical Bottom Line: The reviewed moderate-quality studies support the use of roller massagers but provide limited evidence on the effectiveness of foam rolling to increase hamstrings flexibility in asymptomatic physically active adults. Flexibility gains may be improved by a longer duration of treatment and administration by a trained therapist. Gains appear to decline rapidly postrolling. Neither device has been shown to confer a therapeutic benefit superior to static stretching, and the effectiveness of these devices for preventing injury is unknown. Strength of Recommendation: Grade B evidence supports the use of roller massagers to increase hamstrings flexibility in asymptomatic physically active adults.

  4. An artificial tendon with durable muscle interface.

    Science.gov (United States)

    Melvin, Alan; Litsky, Alan; Mayerson, Joel; Witte, David; Melvin, David; Juncosa-Melvin, Natalia

    2010-02-01

    A coupling mechanism that can permanently fix a forcefully contracting muscle to a bone anchor or any totally inert prosthesis would meet a serious need in orthopaedics. Our group developed the OrthoCoupler device to satisfy these demands. The objective of this study was to test OrthoCoupler's performance in vitro and in vivo in the goat semitendinosus tendon model. For in vitro evaluation, 40 samples were fatigue-tested, cycling at 10 load levels, n = 4 each. For in vivo evaluation, the semitendinosus tendon was removed bilaterally in eight goats. Left sides were reattached with an OrthoCoupler, and right sides were reattached using the Krackow stitch with #5 braided polyester sutures. Specimens were harvested 60 days postsurgery and assigned for biomechanics and histology. Fatigue strength of the devices in vitro was several times the contractile force of the semitendinosus muscle. The in vivo devices were built equivalent to two of the in vitro devices, providing an additional safety factor. In strength testing at necropsy, suture controls pulled out at 120.5 +/- 68.3 N, whereas each OrthoCoupler was still holding after the muscle tore, remotely, at 298 +/- 111.3 N (mean +/- SD) (p < 0.0003). Muscle tear strength was reached with the fiber-muscle composite produced in healing still soundly intact. This technology may be of value for orthopaedic challenges in oncology, revision arthroplasty, tendon transfer, and sports-injury reconstruction. (c) 2009 Orthopaedic Research Society.

  5. The relationship between hamstring length and gluteal muscle strength in individuals with sacroiliac joint dysfunction.

    Science.gov (United States)

    Massoud Arab, Amir; Reza Nourbakhsh, Mohammad; Mohammadifar, Ali

    2011-02-01

    It has been suggested that tight hamstring muscle, due to its anatomical connections, could be a compensatory mechanism for providing sacroiliac (SI) joint stability in patients with gluteal muscle weakness and SIJ dysfunction. The purpose of this study was to determine the relationship between hamstring muscle length and gluteal muscle strength in subjects with sacroiliac joint dysfunction. A total of 159 subjects with and without low back pain (LBP) between the ages of 20 and 65 years participate in the study. Subjects were categorized into three groups: LBP without SIJ involvement (n = 53); back pain with SIJ dysfunction (n = 53); and no low back pain (n = 53). Hamstring muscle length and gluteal muscle strength were measured in all subjects. The number of individuals with gluteal weakness was significantly (P = 0.02) higher in subjects with SI joint dysfunction (66%) compared to those with LBP without SI joint dysfunctions (34%). In pooled data, there was no significant difference (P = 0.31) in hamstring muscle length between subjects with SI joint dysfunction and those with back pain without SI involvement. In subjects with SI joint dysfunction, however, those with gluteal muscle weakness had significantly (P = 0.02) shorter hamstring muscle length (mean = 158±11°) compared to individuals without gluteal weakness (mean = 165±10°). There was no statistically significant difference (P>0.05) in hamstring muscle length between individuals with and without gluteal muscle weakness in other groups. In conclusion, hamstring tightness in subjects with SI joint dysfunction could be related to gluteal muscle weakness. The slight difference in hamstring muscle length found in this study, although statistically significant, was not sufficient for making any definite conclusions. Further studies are needed to establish the role of hamstring muscle in SI joint stability.

  6. Impact of exercise selection on hamstring muscle activation.

    Science.gov (United States)

    Bourne, Matthew N; Williams, Morgan D; Opar, David A; Al Najjar, Aiman; Kerr, Graham K; Shield, Anthony J

    2017-07-01

    To determine which strength training exercises selectively activate the biceps femoris long head (BF LongHead ) muscle. We recruited 24 recreationally active men for this two-part observational study . Part 1: We explored the amplitudes and the ratios of lateral (BF) to medial hamstring (MH) normalised electromyography (nEMG) during the concentric and eccentric phases of 10 common strength training exercises. Part 2: We used functional MRI (fMRI) to determine the spatial patterns of hamstring activation during two exercises which (1) most selectively and (2) least selectively activated the BF in part 1. Eccentrically, the largest BF/MH nEMG ratio occurred in the 45° hip-extension exercise; the lowest was in the Nordic hamstring (Nordic) and bent-knee bridge exercises. Concentrically, the highest BF/MH nEMG ratio occurred during the lunge and 45° hip extension; the lowest was during the leg curl and bent-knee bridge. fMRI revealed a greater BF (LongHead) to semitendinosus activation ratio in the 45° hip extension than the Nordic (phamstring muscles (p≤0.002). We highlight the heterogeneity of hamstring activation patterns in different tasks. Hip-extension exercise selectively activates the long hamstrings, and the Nordic exercise preferentially recruits the semitendinosus. These findings have implications for strategies to prevent hamstring injury as well as potentially for clinicians targeting specific hamstring components for treatment (mechanotherapy). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  7. Double-bundle PCL reconstruction using autologous hamstring tendons: outcome with a minimum 2-year follow-up

    Directory of Open Access Journals (Sweden)

    Ricardo de Paula Leite Cury

    Full Text Available ABSTRACT OBJECTIVE: To present the outcomes of posterior cruciate ligament (PCL double-bundle reconstruction using autologous hamstring tendons, with a minimum follow-up of two years. METHODS: Evaluation of 16 cases of PCL injury that underwent double-bundle reconstruction with autogenous hamstring tendons, between 2011 and 2013. The final sample consisted of 16 patients, 15 men and one woman, with a mean age of 31 years (21-49. The predominant mechanism was motorcycle accident in half of the cases. There was a mean interval of 15 months between the time of lesion and the surgery (three to 52 months. Five lesions were isolated and 11, associated. Clinical evaluation, application of validated scores, and measurements with use of the KT-1000 were performed. RESULTS: The analysis showed a mean preoperative Lysholm score of 50 points (28-87, progressing to 94 points (85-100 postoperatively. The IKDC score also demonstrated improvement. In the preoperative evaluation, four and 12 patients were respectively classified as C (abnormal and D (very unusual, and in the postoperative evaluation six as A (normal and ten as B (close to normal. In the post-operative evaluation by KT1000 arthrometer, 13 patients showed difference between 0-2 mm and 3 between 3 and 5 mm, when compared with the contralateral side. CONCLUSION: Autologous hamstring tendons are a viable option in double-bundle reconstruction of the PCL, with good clinical results in a minimum follow-up of two years.

  8. The difference in passive tension applied to the muscles composing the hamstrings - Comparison among muscles using ultrasound shear wave elastography.

    Science.gov (United States)

    Nakamura, Masatoshi; Hasegawa, Satoshi; Umegaki, Hiroki; Nishishita, Satoru; Kobayashi, Takuya; Fujita, Kosuke; Tanaka, Hiroki; Ibuki, Satoko; Ichihashi, Noriaki

    2016-08-01

    Hamstring muscle strain is one of the most common injuries in sports. Therefore, to investigate the factors influencing hamstring strain, the differences in passive tension applied to the hamstring muscles at the same knee and hip positions as during terminal swing phase would be useful information. In addition, passive tension applied to the hamstrings could change with anterior or posterior tilt of the pelvis. The aims of this study were to investigate the difference in passive tension applied to the individual muscles composing the hamstrings during passive elongation, and to investigate the effect of pelvic position on passive tension. Fifteen healthy men volunteered for this study. The subject lay supine with the angle of the trunk axis to the femur of their dominant leg at 70° and the knee angle of the dominant leg fixed at 30° flexion. In three pelvic positions ("Non-Tilt", "Anterior-Tilt" and "Posterior-Tilt"), the shear elastic modulus of each muscle composing the hamstrings (semitendinosus, semimembranosus, and biceps femoris) was measured using an ultrasound shear wave elastography. The shear elastic modulus of semimembranosus was significantly higher than the others. Shear elastic modulus of the hamstrings in Anterior-Tilt was significantly higher than in Posterior-Tilt. Passive tension applied to semimembranosus is higher than the other muscles when the hamstring muscle is passively elongated, and passive tension applied to the hamstrings increases with anterior tilt of the pelvis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Biology and augmentation of tendon-bone insertion repair

    OpenAIRE

    Lui, PPY; Zhang, P; Chan, KM; Qin, L

    2010-01-01

    Abstract Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL) reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis") which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be ...

  10. Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction.

    Science.gov (United States)

    Fink, Christian; Steensen, Robert; Gföller, Peter; Lawton, Robert

    2018-06-01

    Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction. Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics. Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

  11. Biology and augmentation of tendon-bone insertion repair

    Directory of Open Access Journals (Sweden)

    Lui PPY

    2010-08-01

    Full Text Available Abstract Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis" which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be paid to augment tendon to bone insertion (TBI healing. Apart from surgical fixation, biological and biophysical interventions have been studied aiming at regeneration of TBI healing complex, especially the regeneration of interpositioned fibrocartilage and new bone at the healing junction. This paper described the biology and the factors influencing TBI healing using patella-patellar tendon (PPT healing and tendon graft to bone tunnel healing in ACL reconstruction as examples. Recent development in the improvement of TBI healing and directions for future studies were also reviewed and discussed.

  12. THE EFFECT OF A PELVIC COMPRESSION BELT ON FUNCTIONAL HAMSTRING MUSCLE ACTIVITY IN SPORTSMEN WITH AND WITHOUT PREVIOUS HAMSTRING INJURY.

    Science.gov (United States)

    Arumugam, Ashokan; Milosavljevic, Stephan; Woodley, Stephanie; Sole, Gisela

    2015-06-01

    There is evidence that applying a pelvic compression belt (PCB) can decrease hamstring and lumbar muscle electromyographic activity and increase gluteus maximus activity in healthy women during walking. Increased isokinetic eccentric hamstring strength in the terminal range (25 ° - 5 °) of knee extension has been reported with the use of such a belt in sportsmen with and without hamstring injuries. However, it is unknown whether wearing a pelvic belt alters activity of the hamstrings in sportsmen during walking. To examine the effects of wearing a PCB on electromyographic activity of the hamstring and lumbopelvic muscles during walking in sportsmen with and without hamstring injuries. Randomised crossover, cross-sectional study. Thirty uninjured sportsmen (23.53 ± 3.68 years) and 20 sportsmen with hamstring injuries (22.00 ± 1.45 years) sustained within the previous 12 months participated in this study. Electromyographic amplitudes of the hamstrings, gluteus maximus, gluteus medius and lumbar multifidus were monitored during defined phases of walking and normalised to maximum voluntary isometric contraction. Within-group comparisons [PCB vs. no PCB] for the normalised electromyographic amplitudes were performed for each muscle group using paired t tests. Electromyographic change scores [belt - no belt] were calculated and compared between the two groups with independent t tests. No significant change was evident in hamstring activity for either group while walking with the PCB (p > 0.050). However, with the PCB, gluteus medius activity (p ≤ 0.028) increased in both groups, while gluteus maximus activity increased (p = 0.025) and multifidus activity decreased (p hamstrings during walking, resulting in no significant changes within or between the two groups. Future studies investigating effects of the PCB on hamstring activity in participants with acute injury and during a more demanding functional activity such as running are warranted

  13. Outcome of medial hamstring lengthening in children with spastic paresis: A biomechanical and morphological observational study.

    Science.gov (United States)

    Haberfehlner, Helga; Jaspers, Richard T; Rutz, Erich; Harlaar, Jaap; van der Sluijs, Johannes A; Witbreuk, Melinda M; van Hutten, Kim; Romkes, Jacqueline; Freslier, Marie; Brunner, Reinald; Becher, Jules G; Maas, Huub; Buizer, Annemieke I

    2018-01-01

    To improve gait in children with spastic paresis due to cerebral palsy or hereditary spastic paresis, the semitendinosus muscle is frequently lengthened amongst other medial hamstring muscles by orthopaedic surgery. Side effects on gait due to weakening of the hamstring muscles and overcorrections have been reported. How these side effects relate to semitendinosus morphology is unknown. This study assessed the effects of bilateral medial hamstring lengthening as part of single-event multilevel surgery (SEMLS) on (1) knee joint mechanics (2) semitendinosus muscle morphology and (3) gait kinematics. All variables were assessed for the right side only. Six children with spastic paresis selected for surgery to counteract limited knee range of motion were measured before and about a year after surgery. After surgery, in most subjects popliteal angle decreased and knee moment-angle curves were shifted towards a more extended knee joint, semitendinosus muscle belly length was approximately 30% decreased, while at all assessed knee angles tendon length was increased by about 80%. In the majority of children muscle volume of the semitendinosus muscle decreased substantially suggesting a reduction of physiological cross-sectional area. Gait kinematics showed more knee extension during stance (mean change ± standard deviation: 34±13°), but also increased pelvic anterior tilt (mean change ± standard deviation: 23±5°). In most subjects, surgical lengthening of semitendinosus tendon contributed to more extended knee joint angle during static measurements as well as during gait, whereas extensibility of semitendinosus muscle belly was decreased. Post-surgical treatment to maintain muscle belly length and physiological cross-sectional area may improve treatment outcome of medial hamstring lengthening.

  14. Three-Dimensional Bio-Printed Scaffold Sleeves With Mesenchymal Stem Cells for Enhancement of Tendon-to-Bone Healing in Anterior Cruciate Ligament Reconstruction Using Soft-Tissue Tendon Graft.

    Science.gov (United States)

    Park, Sin Hyung; Choi, Yeong-Jin; Moon, Sang Won; Lee, Byung Hoon; Shim, Jin-Hyung; Cho, Dong-Woo; Wang, Joon Ho

    2018-01-01

    To investigate the efficacy of the insertion of 3-dimensional (3D) bio-printed scaffold sleeves seeded with mesenchymal stem cells (MSCs) to enhance osteointegration between the tendon and tunnel bone in anterior cruciate ligament (ACL) reconstruction in a rabbit model. Scaffold sleeves were fabricated by 3D bio-printing. Before ACL reconstruction, MSCs were seeded into the scaffold sleeves. ACL reconstruction with hamstring tendon was performed on both legs of 15 adult rabbits (aged 12 weeks). We implanted 15 bone tunnels with scaffold sleeves with MSCs and implanted another 15 bone tunnels with scaffold sleeves without MSCs before passing the graft. The specimens were harvested at 4, 8, and 12 weeks. H&E staining, immunohistochemical staining of type II collagen, and micro-computed tomography of the tunnel cross-sectional area were evaluated. Histologic assessment was conducted with a histologic scoring system. In the histologic assessment, a smooth bone-to-tendon transition through broad fibrocartilage formation was identified in the treatment group, and the interface zone showed abundant type II collagen production on immunohistochemical staining. Bone-tendon healing histologic scores were significantly higher in the treatment group than in the control group at all time points. Micro-computed tomography at 12 weeks showed smaller tibial (control, 9.4 ± 0.9 mm 2 ; treatment, 5.8 ± 2.9 mm 2 ; P = .044) and femoral (control, 9.6 ± 2.9 mm 2 ; treatment, 6.0 ± 1.0 mm 2 ; P = .03) bone-tunnel areas in the treated group than in the control group. The 3D bio-printed scaffold sleeve with MSCs exhibited excellent results in osteointegration enhancement between the tendon and tunnel bone in ACL reconstruction in a rabbit model. If secure biological healing between the tendon graft and tunnel bone can be induced in the early postoperative period, earlier, more successful rehabilitation may be facilitated. Three-dimensional bio-printed scaffold sleeves with

  15. Changes in Passive Tension of the Hamstring Muscles During a Simulated Soccer Match.

    Science.gov (United States)

    Marshall, Paul W; Lovell, Ric; Siegler, Jason C

    2016-07-01

    Passive muscle tension is increased after damaging eccentric exercise. Hamstring-strain injury is associated with damaging eccentric muscle actions, but no research has examined changes in hamstring passive muscle tension throughout a simulated sport activity. The authors measured hamstring passive tension throughout a 90-min simulated soccer match (SAFT90), including the warm-up period and every 15 min throughout the 90-min simulation. Passive hamstring tension of 15 amateur male soccer players was measured using the instrumented straight-leg-raise test. Absolute torque (Nm) and slope (Nm/°) of the recorded torque-angular position curve were used for data analysis, in addition to total leg range of motion (ROM). Players performed a 15-min prematch warm-up, then performed the SAFT90 including a 15-min halftime rest period. Reductions in passive stiffness of 20-50° of passive hip flexion of 22.1-29.2% (P hamstring ROM (P = .0009). The findings of this study imply that hamstring passive tension is reduced after an active warm-up that includes dynamic stretching but does not increase in a pattern suggestive of eccentric induced muscle damage during soccer-specific intermittent exercise. Hamstring ROM and passive tension increases are best explained by improved stretch tolerance.

  16. Hamstring strain - aftercare

    Science.gov (United States)

    Pulled hamstring muscle; Sprain - hamstring ... There are 3 levels of hamstring strains: Grade 1 -- mild muscle strain or pull Grade 2 -- partial muscle tear Grade 3 -- complete muscle tear Recovery time depends ...

  17. Hamstring Injury

    Science.gov (United States)

    Hamstring injury Overview A hamstring injury occurs when you strain or pull one of your hamstring muscles — the group of three muscles that run along ... You may be more likely to get a hamstring injury if you play soccer, basketball, football, tennis ...

  18. Knee Moment-Angle Characteristics and Semitendinosus Muscle Morphology in Children with Spastic Paresis Selected for Medial Hamstring Lengthening.

    Science.gov (United States)

    Haberfehlner, Helga; Jaspers, Richard T; Rutz, Erich; Becher, Jules G; Harlaar, Jaap; van der Sluijs, Johannes A; Witbreuk, Melinda M; Romkes, Jacqueline; Freslier, Marie; Brunner, Reinald; Maas, Huub; Buizer, Annemieke I

    2016-01-01

    To increase knee range of motion and improve gait in children with spastic paresis (SP), the semitendinosus muscle (ST) amongst other hamstring muscles is frequently lengthened by surgery, but with variable success. Little is known about how the pre-surgical mechanical and morphological characteristics of ST muscle differ between children with SP and typically developing children (TD). The aims of this study were to assess (1) how knee moment-angle characteristics and ST morphology in children with SP selected for medial hamstring lengthening differ from TD children, as well as (2) how knee moment-angle characteristics and ST morphology are related. In nine SP and nine TD children, passive knee moment-angle characteristics and morphology of ST (i.e. fascicle length, muscle belly length, tendon length, physiological cross-sectional area, and volume) were assessed by hand-held dynamometry and freehand 3D ultrasound, respectively. At net knee flexion moments above 0.5 Nm, more flexed knee angles were found for SP compared to TD children. The measured knee angle range between 0 and 4 Nm was 30% smaller in children with SP. Muscle volume, physiological cross-sectional area, and fascicle length normalized to femur length were smaller in SP compared to TD children (62%, 48%, and 18%, respectively). Sixty percent of the variation in knee angles at 4 Nm net knee moment was explained by ST fascicle length. Altered knee moment-angle characteristics indicate an increased ST stiffness in SP children. Morphological observations indicate that in SP children planned for medial hamstring lengthening, the longitudinal and cross-sectional growth of ST muscle fibers is reduced. The reduced fascicle length can partly explain the increased ST stiffness and, hence, a more flexed knee joint in these SP children.

  19. Selective and graded recruitment of cat hamstring muscles with intrafascicular stimulation.

    Science.gov (United States)

    Dowden, Brett R; Wilder, Andrew M; Hiatt, Scott D; Normann, Richard A; Brown, Nicholas A T; Clark, Gregory A

    2009-12-01

    The muscles of the hamstring group can produce different combinations of hip and knee torque. Thus, the ability to activate the different hamstring muscles selectively is of particular importance in eliciting functional movements such as stance and gait in a person with spinal cord injury. We investigated the ability of intrafascicular stimulation of the muscular branch of the sciatic nerve to recruit the feline hamstring muscles in a selective and graded fashion. A Utah Slanted Electrode Array, consisting of 100 penetrating microelectrodes, was implanted into the muscular branch of the sciatic nerve in six cats. Muscle twitches were evoked in the three compartments of biceps femoris (anterior, middle, and posterior), as well as semitendinosus and semimembranosus, using pulse-width modulated constant-voltage pulses. The resultant compound muscle action potentials were recorded using intramuscular fine-wire electrodes. 74% of the electrodes per implant were able to evoke a threshold response in these muscles, and these electrodes were evenly distributed among the instrumented muscles. Of the five muscles instrumented, on average 2.5 could be selectively activated to 90% of maximum EMG, and 3.5 could be selectively activated to 50% of maximum EMG. The muscles were recruited selectively with a mean stimulus dynamic range of 4.14 +/- 5.05 dB between threshold and either spillover to another muscle or a plateau in the response. This selective and graded activation afforded by intrafascicular stimulation of the muscular branch of the sciatic nerve suggests that it is a potentially useful stimulation paradigm for eliciting distinct forces in the hamstring muscle group in motor neuroprosthetic applications.

  20. One-stage bilateral anterior cruciate ligament reconstruction with use of hamstring tendon autografts: a case report

    Directory of Open Access Journals (Sweden)

    Matjaž Sajovic

    2007-12-01

    Full Text Available Background: Bilateral ACL rupture is not a common clinical problem, but the incidence of the bilateral knee injuries is increasing especially within highly sports active population. Mechanism of the injury rarely causes simultaneous bilateral ACL tear. Usually unilateral injury of the knee has occurred and later on contralateral injury has taken place.Patient and methods: Case report presented an unusual problem of a patient with chronic bilateral ACL – deficient knees and constitutionally very thin patellar tendons. Author decided to perform onestage bilateral ACL reconstructions using hamstring tendon autographs so as not too weaken his quadriceps muscles by compromising his extensor mechanism.Results: At three years follow-up the patient’s opinion was that both ACL reconstructed knees had normal function, and he had returned to his preinjury activity level. The overall result of the Lysholm knee score for left knee was 100 and for right one 95. Both knees had full range of motion, Lachman and pivot shift signs were negative.Conclusions: Two-stage bilateral ACL reconstruction is much more time consuming for the patient and expensive for health insurance, so one-stage bilateral ACL reconstruction is a logical solution of the problem.

  1. Effects of knee immobilization on morphological changes in the semitendinosus muscle-tendon complex after hamstring harvesting for anterior cruciate ligament reconstruction. Evaluation using three-dimensional computed tomography

    International Nuclear Information System (INIS)

    Nakamae, Atsuo; Adachi, Nobuo; Nakasa, Tomoyuki; Nishimori, Makoto; Ochi, Mitsuo; Deie, Masataka

    2012-01-01

    It is desirable to maintain the morphology of the semitendinosus muscle-tendon complex after tendon harvesting for anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to evaluate the effect of knee immobilization on morphological changes in the semitendinosus muscle-tendon complex. In total, 39 patients who underwent ACL reconstruction with autologous semitendinosus tendons were included in this study. After surgery, the knee was immobilized for 3 days in 1 group of patients (group 1; 24 patients; control group) and for a longer period (10-14 days) in the other group (group 2; 15 patients). Three-dimensional computed tomography (3D CT) examination was performed at 6 and/or 12 months after the surgery for all patients. Morphological changes in the semitendinosus muscle-tendon complex (proximal shift of the semitendinosus muscle-tendon junction, width of the regenerated semitendinosus tendons, re-insertion sites of the regenerated tendons, and rate of semitendinosus tendon regeneration) were evaluated. Successful regeneration of the semitendinosus tendon was confirmed in all patients in group 2. In group 1, 3D CT showed that regeneration of the semitendinosus tendon was unsuccessful in 1 of the 24 patients. The average length of the proximal shift of the semitendinosus muscle-tendon junction was 7.3±2.5 cm in group 1 and 7.2±1.9 cm in group 2. There were no significant differences between the 2 groups with regard to the morphological changes in the semitendinosus muscle-tendon complex. This study showed that the structure of regenerated tendons could be clearly identified in 38 of 39 cases (97.4%) after ACL reconstruction. However, prolonged knee immobilization (10-14 days) could not prevent morphological changes in the semitendinosus muscle-tendon complex. (author)

  2. Hamstring injuries: prevention and treatment—an update

    Science.gov (United States)

    Brukner, Peter

    2015-01-01

    Despite increased knowledge of hamstring muscle injuries, the incidence has not diminished. We now know that not all hamstring injuries are the same and that certain types of injuries require prolonged rehabilitation and return to play. The slow stretch type of injury and injuries involving the central tendon both require longer times to return to play. A number of factors have been proposed as being indicators of time taken to return to play, but the evidence for these is conflicting. Recurrence rates remain high and it is now thought that strength deficits may be an important factor. Strengthening exercise should be performed with the hamstrings in a lengthened position. There is conflicting evidence regarding the efficacy of platelet-rich plasma injection in the treatment of hamstring injuries so at this stage we cannot advise their use. Various tests have been proposed as predictors of hamstring injury and the use of the Nordboard is an interesting addition to the testing process. Prevention of these injuries is the ultimate aim and there is increasing evidence that Nordic hamstring exercises are effective in reducing the incidence. PMID:26105015

  3. Prone Hip Extension Muscle Recruitment is Associated with Hamstring Injury Risk in Amateur Soccer.

    Science.gov (United States)

    Schuermans, Joke; Van Tiggelen, Damien; Witvrouw, Erik

    2017-09-01

    'Core stability' is considered essential in rehabilitation and prevention. Particularly with respect to hamstring injury prevention, assessment and training of lumbo-pelvic control is thought to be key. However, supporting scientific evidence is lacking. To explore the importance of proximal neuromuscular function with regard to hamstring injury susceptibility, this study investigated the association between the Prone Hip Extension (PHE) muscle activation pattern and hamstring injury incidence in amateur soccer players. 60 healthy male soccer players underwent a comprehensive clinical examination, comprising a range of motion assessments and the investigation of the posterior chain muscle activation pattern during PHE. Subsequently, hamstring injury incidence was recorded prospectively throughout a 1.5-season monitoring period. Players who were injured presented a PHE activation pattern that differed significantly from those who did not. Contrary to the controls, hamstring activity onset was significantly delayed (p=0.018), resulting in a shifted activation sequence. Players were 8 times more likely to get injured if the hamstring muscles were activated after the lumbar erector spinae instead of vice versa (p=0.009). Assessment of muscle recruitment during PHE demonstrated to be useful in injury prediction, suggesting that neuromuscular coordination in the posterior chain influences hamstring injury vulnerability. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Musculoskeletal Geometry, Muscle Architecture and Functional Specialisations of the Mouse Hindlimb (Open Access)

    Science.gov (United States)

    2016-04-26

    example, studies in cats [18], guinea pigs [16] and rabbits [19] have shown that the hamstring muscles, a bi-articular group of muscles which act around...energy in compliant tendons [20, 21], whereas others, such as the hamstrings (hip extensors and knee flexors), function to produce fast contractions

  5. A New Option for the Reconstruction of Primary or Recurrent Ischial Pressure Sores: Hamstring-Adductor Magnus Muscle Advancement Flap and Direct Closure.

    Science.gov (United States)

    Burm, Jin Sik; Hwang, Jungil; Lee, Yung Ki

    2018-04-01

    Owing to the high recurrence rates of ischial pressure sores, surgeons should consider the possibility of future secondary flap surgery during flap selection. The purpose of this article is to present a new surgical option for the reconstruction of primary or recurrent ischial pressure sores using a simple hamstring-adductor magnus advancement flap and direct closure. After horizontal fusiform skin excision, complete bursa excision and ischiectomy were performed. The tenomuscular origin of the adductor magnus and the conjoined tenomuscular origin of the biceps femoris long head and semitendinosus were isolated and completely detached from the inferior border of the ischial tuberosity. They were then advanced in a cephalad direction without detachment of the distal tendon or muscle and securely affixed to the sacrotuberous ligament. The wound was directly closed without further incision or dissection. Twelve ischial pressure sores (6 primary and 6 recurrent; 12 patients) were surgically corrected. The follow-up period was 12 to 65 months. All patients healed successfully without early postoperative complications, such as hematoma, seroma, infection, wound dehiscence, or partial necrosis. Late complications included wound disruption 5 weeks after surgery that spontaneously healed in 1 case and recurrence 3 years later in another case. The new surgical option presented herein, which involves hamstring-adductor magnus advancement flap and direct closure, is a simple and reliable method for providing sufficient muscle bulk to fill the dead space and proper padding to the bone stump while preserving the main vascular perforators and pedicles as well as future surgical options.

  6. Serial Changes of Quadriceps and Hamstring Muscle Strength Following Total Knee Arthroplasty: A Meta-Analysis

    Science.gov (United States)

    Ahn, Hyeong-Sik; Lee, Dae-Hee

    2016-01-01

    This meta-analysis was performed to analyze serial changes in thigh muscles, including quadriceps and hamstring muscles, from before to one year after total knee arthroplasty (TKA). All studies sequentially comparing isokinetic quadriceps and hamstring muscle strengths between the TKA side and the contralateral uninjured limb were included in this meta-analysis. Five studies with 7 cohorts were included in this meta-analysis. The mean differences in the strengths of quadriceps and hamstring muscles between the TKA and uninjured sides were greatest three months after surgery (26.8 N∙m, 12.8 N∙m, Phamstring strengths relative to preoperative levels were 9.2 N∙m and 4.9 N∙m, respectively, three months postoperatively (P = 0.041), but were no longer significant after six months and one year. During the year after TKA, quadriceps and hamstring muscle strengths were lowest after 3 months, recovering to preoperative level after six months, but not reaching the muscle strength on the contralateral side. Relative to preoperative levels, the difference in muscle strength between the TKA and contralateral knees was only significant at three months. Because decrease of strength of the quadriceps was significantly greater than decrease in hamstring muscle strength at postoperative three months, early rehabilitation after TKA should focus on recovery of quadriceps muscle strength. PMID:26849808

  7. A comparison of hamstring muscle activity during different screening tests for non-contact ACL injury

    DEFF Research Database (Denmark)

    Husted, Rasmus S; Bencke, Jesper; Andersen, Lars Louis

    2016-01-01

    phenomenon and thereby observable independently of the type of clinical screening tests used is not known. This cross sectional study investigated the rank correlation of knee joint neuromuscular activity between three different ACL injury risk screening tests. METHODS: Sixty-two adolescent female elite......BACKGROUND: Reduced ability to activate the medial hamstring muscles during a sports-specific sidecutting movement has been found to be a potential risk factor for non-contact ACL injury. However, whether a reduced ability to activate the medial hamstring muscle is a general neuromuscular...... football and handball players (16.7±1.3years) participated in the study. Using surface electromyography (EMG) assessment, the neuromuscular activity of medial hamstring muscle (semitendinosus, ST), lateral hamstring muscle (biceps femoris, BF) and quadriceps muscle (vastus lateralis, VL) were monitored...

  8. Anterior cruciate ligament- and hamstring tendon- derived cells: in vitro differential properties of cells involved in ACL reconstruction

    NARCIS (Netherlands)

    Ghebes, C.A.; Kelder, C.; Schot, T.; Renard, A.J.S.; Pakvis, D.F.M.; Fernandes, H.; Saris, Daniël B.F.

    2015-01-01

    Anterior cruciate ligament (ACL) reconstruction involves the replacement of the torn ligament with a new graft, often a hamstring tendon (HT). Described as similar, the ACL and HT have intrinsic differences related to their distinct anatomical locations. From a cellular perspective, identifying

  9. Should the Ipsilateral Hamstrings Be Used for Anterior Cruciate Ligament Reconstruction in the Case of Medial Collateral Ligament Insufficiency? Biomechanical Investigation Regarding Dynamic Stabilization of the Medial Compartment by the Hamstring Muscles.

    Science.gov (United States)

    Herbort, Mirco; Michel, Philipp; Raschke, Michael J; Vogel, Nils; Schulze, Martin; Zoll, Alexander; Fink, Christian; Petersen, Wolf; Domnick, Christoph

    2017-03-01

    Semitendinosus and gracilis muscles are frequently harvested for autologous tendon grafts for cruciate ligament reconstruction. This study investigated the joint-stabilizing effects of these hamstring muscles in cases of insufficiency of the medial collateral ligament (MCL). First, both the semitendinosus and gracilis muscles can actively stabilize the joint against valgus moments in the MCL-deficient knee. Second, the stabilizing influence of these muscles decreases with an increasing knee flexion angle. Controlled laboratory study. The kinematics was examined in 10 fresh-frozen human cadaveric knees using a robotic/universal force moment sensor system and an optical tracking system. The knee kinematics under 5- and 10-N·m valgus moments were determined in the different flexion angles of the (1) MCL-intact and (2) MCL-deficient knee using the following simulated muscle loads: (1) 0-N (idle) load, (2) 200-N semitendinosus (ST) load, and (3) 280-N (200/80-N) combined semitendinosus/gracilis (STGT) load. Cutting the MCL increased the valgus angle under all tested conditions and angles compared with the MCL-intact knee by 4.3° to 8.1° for the 5-N·m valgus moment and 6.5° to 11.9° for the 10-N·m valgus moment ( P .05). The combined 280-N simulated STGT load significantly reduced the valgus angle in 0°, 10°, and 20° of flexion under 5- and 10-N·m valgus moments ( P .05). In 60° and 90° of flexion, ST and STGT loads did not decrease the resulting valgus angle of the MCL-deficient knee without hamstring loads ( P > .05 vs deficient; P = .0001 vs intact). In this human cadaveric study, semitendinosus and gracilis muscles successfully stabilize valgus moments applied to the MCL-insufficient knee when the knee is near extension. In the valgus-unstable knee, these data suggest that the hamstring muscles should be preserved in (multi-) ligament surgery when possible.

  10. The series-elastic shock absorber: tendons attenuate muscle power during eccentric actions.

    Science.gov (United States)

    Roberts, Thomas J; Azizi, Emanuel

    2010-08-01

    Elastic tendons can act as muscle power amplifiers or energy-conserving springs during locomotion. We used an in situ muscle-tendon preparation to examine the mechanical function of tendons during lengthening contractions, when muscles absorb energy. Force, length, and power were measured in the lateral gastrocnemius muscle of wild turkeys. Sonomicrometry was used to measure muscle fascicle length independently from muscle-tendon unit (MTU) length, as measured by a muscle lever system (servomotor). A series of ramp stretches of varying velocities was applied to the MTU in fully activated muscles. Fascicle length changes were decoupled from length changes imposed on the MTU by the servomotor. Under most conditions, muscle fascicles shortened on average, while the MTU lengthened. Energy input to the MTU during the fastest lengthenings was -54.4 J/kg, while estimated work input to the muscle fascicles during this period was only -11.24 J/kg. This discrepancy indicates that energy was first absorbed by elastic elements, then released to do work on muscle fascicles after the lengthening phase of the contraction. The temporary storage of energy by elastic elements also resulted in a significant attenuation of power input to the muscle fascicles. At the fastest lengthening rates, peak instantaneous power input to the MTU reached -2,143.9 W/kg, while peak power input to the fascicles was only -557.6 W/kg. These results demonstrate that tendons may act as mechanical buffers by limiting peak muscle forces, lengthening rates, and power inputs during energy-absorbing contractions.

  11. ROLE OF HAMSTRING MUSCLES IN KNEE JOINT STABILITY PROVIDING AND INJURY PREVENTION

    OpenAIRE

    Pontaga, Inese

    2016-01-01

    The aim of our investigation was to determine the ratio of maximal torque values and the torques in the certain positions of range of movements (ROM) between hamstring (H) and quadriceps femoris (Q) muscles at medium and high velocity of movement in concentric (CC) and eccentric (ECC) action of hamstring muscles. The knee muscles of 15 amateur female short and middle distance runners were tested by the dynamometer system in the isokinetic movements with the angular velocity of 90º/s and 240º...

  12. Intramuscular tendon involvement on MRI has limited value for predicting time to return to play following acute hamstring injury.

    Science.gov (United States)

    van der Made, Anne D; Almusa, Emad; Whiteley, Rod; Hamilton, Bruce; Eirale, Cristiano; van Hellemondt, Frank; Tol, Johannes L

    2018-01-01

    Hamstring injury with intramuscular tendon involvement is regarded as a serious injury with a delay in return to play (RTP) of more than 50 days and reinjury rates up to 63%. However, this reputation is based on retrospective case series with high risk of bias. Determine whether intramuscular tendon involvement is associated with delayed RTP and elevated rates of reinjury. MRI of male athletes with an acute hamstring injury was obtained within 5 days of injury. Evaluation included standardised MRI scoring and scoring of intramuscular tendon involvement. Time to RTP and reinjury rate were prospectively recorded. Out of 70 included participants, intramuscular tendon disruption was present in 29 (41.4%) injuries. Injuries without intramuscular tendon disruption had a mean time to RTP of 22.2±7.4 days. Injuries with Injuries with full-thickness disruption took longer to RTP compared with injuries without disruption (p=0.025). Longitudinal intramuscular tendon disruption was not significantly associated with time to RTP. Waviness was present in 17 (24.3%) injuries. Mean time to RTP for injuries without and with waviness was 22.6±7.5 and 30.2±10.8 days (p=0.014). There were 11 (15.7%) reinjuries within 12 months, five (17.2%) in the group with intramuscular tendon disruption and six (14.6%) in the group without intramuscular tendon disruption. Time to RTP for injuries with full-thickness disruption of the intramuscular tendon and waviness is significantly longer (by slightly more than 1 week) compared with injuries without intramuscular tendon involvement. However, due to the considerable overlap in time to RTP between groups with and without intramuscular tendon involvement, its clinical significance for the individual athlete is limited. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Rehabilitation of hamstring muscle injuries: a literature review

    Directory of Open Access Journals (Sweden)

    Gabriel Amorim Ramos

    Full Text Available ABSTRACT Hamstring injuries are among the most frequent in sports. The high relapse rate is a challenge for sports medicine and has a great impact on athletes and sport teams. The treatment goal is to provide the athlete the same functional level as before the injury. Thus, functional rehabilitation is very important to the success of the treatment. Currently, several physical therapy modalities are used, according to the stage of the lesion, such as cryotherapy, laser therapy, therapeutic ultrasound, therapeutic exercise, and manual therapy. However, the evidence of the effectiveness of these modalities in muscle injuries is not fully established due to the little scientific research on the topic. This article presents an overview of the physiotherapy approach in the rehabilitation of hamstring muscle injuries.

  14. BET 2: LASER THERAPY IN THE TREATMENT OF ACUTE HAMSTRING MUSCLE INJURIES.

    Science.gov (United States)

    Hughes, Tom; Callaghan, Michael

    2017-04-01

    Local laser therapy has been suggested as a promising treatment for acute hamstring muscle tears. We carried out a shortcut systematic review to establish whether therapeutic lasers are beneficial for patients with acute hamstring tears. Despite a comprehensive literature search, no studies that were directly relevant to the question could be identified. The clinical bottom line is therefore that there is currently no evidence for the use of any form of laser therapy in the treatment of acute hamstring muscle tears. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. Effects of external pelvic compression on electromyographic activity of the hamstring muscles during unipedal stance in sportsmen with and without hamstring injuries.

    Science.gov (United States)

    Arumugam, Ashokan; Milosavljevic, Stephan; Woodley, Stephanie; Sole, Gisela

    2015-06-01

    There is some evidence that hamstring function can be influenced by interventions focusing on the pelvis via an anatomic and neurophysiologic link between these two segments. Previous research demonstrated increased electromyographic activity from injured hamstrings during transition from bipedal to unipedal stance (BUS). The aim of this study was to investigate the effects of a pelvic compression belt (PCB) on electromyographic activity of selected muscles during BUS in sportsmen with and without hamstring injury. Electromyographic amplitudes (normalised to maximum voluntary isometric contraction [MVIC]) of the hamstrings, gluteus maximus, gluteus medius and lumbar multifidus were obtained during BUS from 20 hamstring-injured participants (both sides) and 30 healthy participants (one side, randomly selected). There was an increase in biceps femoris (by 1.23 ± 2.87 %MVIC; p = 0.027) and gluteus maximus (by 0.63 ± 1.13 %MVIC; p = 0.023) electromyographic activity for the hamstring-injured side but no significant differences other than a decrease in multifidus activity (by 1.36 ± 2.92 %MVIC; p = 0.023) were evident for healthy participants while wearing the PCB. However, the effect sizes for these findings were small. Wearing the PCB did not significantly change electromyographic activity of other muscles in either participant group (p > 0.050). Moreover, the magnitude of change induced by the PCB was not significantly different between groups (p > 0.050) for the investigated muscles. Thus, application of a PCB to decrease electromyographic activity of injured hamstrings during BUS is likely to have little effect. Similar research is warranted in participants with acute hamstring injury. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Relationship between the cervical component of the slump test and change in hamstring muscle tension.

    Science.gov (United States)

    Lew, P. C.; Briggs, C. A.

    1997-05-01

    SUMMARY. The slump test has been used routinely to differentiate low back pain due to involvement of neural structures from low back pain attributable to other factors. It is also said to differentiate between posterior thigh pain due to neural involvement from that due to hamstring injury. If changes in cervical position affect the hamstring muscles, differential diagnosis is confounded. Posterior thigh pain caused by the cervical component of the slump could then be caused either by increased tension on neural structures or increased tension in the hamstrings themselves. The aim of this study was to determine whether changing the cervical position during slump altered posterior thigh pain and/or the tension in the hamstring muscle. Asymptomatic subjects aged between 18 and 30 years were tested. A special fixation device was engineered to fix the trunk, pelvis and lower limb. Pain levels in cervical flexion and extension were assessed by visual analogue scale. Fixation was successful in that there were no significant differences in position of the pelvis or knee during changes in cervical position. Averaged over the group, there was a 40% decrease (P pain with cervical extension. There were no significant differences in hamstring electromyographic readings during the cervical movements. This indicated that: (1) cervical movement did not change hamstring muscle tension, and (2) the change in experimentally induced pain during cervical flexion was not due to changes in the hamstring muscle. This conclusion supports the view that posterior thigh pain caused by the slump test and relieved by cervical extension arises from neural structures rather than the hamstring muscle. Copyright 1997 Harcourt Publishers Ltd.

  17. An Artificial Tendon with Durable Muscle Interface

    OpenAIRE

    Melvin, Alan; Litsky, Alan; Mayerson, Joel; Witte, David; Melvin, David; Juncosa-Melvin, Natalia

    2010-01-01

    A coupling mechanism that can permanently fix a forcefully contracting muscle to a bone anchor or any totally inert prosthesis would meet a serious need in orthopaedics. Our group developed the OrthoCoupler™ device to satisfy these demands. The objective of this study was to test OrthoCoupler’s performance in vitro and in vivo in the goat semitendinosus tendon model. For in vitro evaluation, 40 samples were fatigue-tested, cycling at 10 load levels, n=4 each. For in vivo evaluation, the semit...

  18. Change in muscle thickness under contracting conditions following return to sports after a hamstring muscle strain injury—A pilot study

    Directory of Open Access Journals (Sweden)

    Yasuharu Nagano

    2015-04-01

    Full Text Available The purpose of this study was to measure the change in hamstring muscle thickness between contracting and relaxing conditions following a return to sports after a hamstring muscle strain and thereby evaluate muscle function. Six male track and field sprinters participated in this study. All had experienced a prior hamstring strain injury that required a minimum of 2 weeks away from sport participation. Transverse plane scans were performed at the following four points on the affected and unaffected sides under contracting and relaxing conditions: proximal biceps femoris long head, proximal semitendinosus, middle biceps femoris long head, and middle semitendinosus. The results demonstrated an increase in the thickness of the middle biceps femoris long head and middle semitendinosus regions on the unaffected side with contraction, whereas the affected side did not show a significant increase. The proximal semitendinosus muscle thickness was increased with contraction on both the unaffected and the affected sides. By contrast, the proximal biceps femoris muscle thickness did not show a significant increase on both sides. The results of this study show that evaluation of muscle thickness during contraction may be useful for assessing the change in muscle function after a hamstring muscle strain injury.

  19. The energetic benefits of tendon springs in running: is the reduction of muscle work important?

    Science.gov (United States)

    Holt, Natalie C; Roberts, Thomas J; Askew, Graham N

    2014-12-15

    The distal muscle-tendon units of cursorial species are commonly composed of short muscle fibres and long, compliant tendons. It is assumed that the ability of these tendons to store and return mechanical energy over the course of a stride, thus avoiding the cyclic absorption and regeneration of mechanical energy by active muscle, offers some metabolic energy savings during running. However, this assumption has not been tested directly. We used muscle ergometry and myothermic measurements to determine the cost of force production in muscles acting isometrically, as they could if mechanical energy was stored and returned by tendon, and undergoing active stretch-shorten cycles, as they would if mechanical energy was absorbed and regenerated by muscle. We found no detectable difference in the cost of force production in isometric cycles compared with stretch-shorten cycles. This result suggests that replacing muscle stretch-shorten work with tendon elastic energy storage and recovery does not reduce the cost of force production. This calls into question the assumption that reduction of muscle work drove the evolution of long distal tendons. We propose that the energetic benefits of tendons are derived primarily from their effect on muscle and limb architecture rather than their ability to reduce the cyclic work of muscle. © 2014. Published by The Company of Biologists Ltd.

  20. Influence of Anterior Cruciate Ligament Tear on Thigh Muscle Strength and Hamstring-to-Quadriceps Ratio: A Meta-Analysis

    Science.gov (United States)

    Ahn, Sung-Eun; Park, Min-Ji; Lee, Dae-Hee

    2016-01-01

    Theoretical compensation after anterior cruciate ligament (ACL) tear could cause quadriceps weakness and hamstring activation, preventing anterior tibial subluxation and affecting the expected hamstring-to-quadriceps ratio. Although quadriceps weakness often occurs after ACL tears, it remains unclear whether hamstring strength and hamstring-to-quadriceps ratio increase in ACL deficient knees. This meta-analysis compared the isokinetic muscle strength of quadriceps and hamstring muscles, and the hamstring-to-quadriceps ratio, of the injured and injured limbs of patients with ACL tears. This meta-analysis included all studies comparing isokinetic thigh muscle strengths and hamstring-to-quadriceps ratio in the injured and uninjured legs of patients with ACL tear, without or before surgery. Thirteen studies were included in the meta-analysis. Quadriceps and hamstring strengths were 22.3 N∙m (95% CI: 15.2 to 29.3 N∙m; Phamstring-to-quadriceps ratio was 4% greater in ACL deficient than in uninjured limbs (95% CI: 1.7% to 6.3%; Phamstring muscles of patients with ACL tear, with the decrease in quadriceps strength being 3-fold greater. These uneven reductions slightly increase the hamstring-to-quadriceps ratio in ACL deficient knees. PMID:26745808

  1. Ultrasound diagnostics of muscle and tendon injuries

    Directory of Open Access Journals (Sweden)

    Stević Ruža

    2009-01-01

    Full Text Available Introduction. Sonography is a useful technique for the investigation of a number of musculoskeletal disorders. The most common indication for ultrasonography of muscles and tendons is the diagnosis of traumatic lesions, distinguishing them from other disorders and follow-up of healing process. Objective. The purpose of this paper is to show the importance of ultrasound in the diagnosis of muscle and tendon injuries. Methods. The study included 170 patients (148 male and 22 female, mean age 29.6 years (range 14-60 years. All examinations were performed by linear transducer of 7.5-10 MHz, with longitudinal and transverse scanning. Ultrasound examination followed physical examination. Results. Traumatic lesions of muscles were diagnosed in 113 patients (66.7% and tendon injuries in 57 cases (33.2%. The muscle changes detected by ultrasonography were the following: 70 (61.9% partial and two (1.76% complete ruptures, 22 (19.46% haematoma, 9 (7.96% strains grade I, 4 fibroses and 4 ossifying myositis 4 (3.5%, respectively. Complications of muscle injuries were diagnosed in two cases, a muscular hernia and an arteriovenous fistula. Among tendon injuries, 21 (33.8% ruptures and 36 (66.1% tendinitis were diagnosed. Accompanying effusion in the bursa of patients with tendon injuries was found in 9 cases. Conclusion. Ultrasonography allowed visualization and objective assessment of the type and the extent of traumatic pathomorphological changes of muscles and tendons. Such diagnostic possibilities of ultrasonography are especially important in the choice of appropriate therapy.

  2. Tendon Reattachment to Bone in an Ovine Tendon Defect Model of Retraction Using Allogenic and Xenogenic Demineralised Bone Matrix Incorporated with Mesenchymal Stem Cells.

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    Tanujan Thangarajah

    Full Text Available Tendon-bone healing following rotator cuff repairs is mainly impaired by poor tissue quality. Demineralised bone matrix promotes healing of the tendon-bone interface but its role in the treatment of tendon tears with retraction has not been investigated. We hypothesized that cortical demineralised bone matrix used with minimally manipulated mesenchymal stem cells will result in improved function and restoration of the tendon-bone interface with no difference between xenogenic and allogenic scaffolds.In an ovine model, the patellar tendon was detached from the tibial tuberosity and a complete distal tendon transverse defect measuring 1 cm was created. Suture anchors were used to reattach the tendon and xenogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5, or allogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5 were used to bridge the defect. Graft incorporation into the tendon and its effect on regeneration of the enthesis was assessed using histomorphometry. Force plate analysis was used to assess functional recovery.Compared to the xenograft, the allograft was associated with significantly higher functional weight bearing at 6 (P = 0.047, 9 (P = 0.028, and 12 weeks (P = 0.009. In the allogenic group this was accompanied by greater remodeling of the demineralised bone matrix into tendon-like tissue in the region of the defect (p = 0.015, and a more direct type of enthesis characterized by significantly more fibrocartilage (p = 0.039. No failures of tendon-bone healing were noted in either group.Demineralised bone matrix used with minimally manipulated mesenchymal stem cells promotes healing of the tendon-bone interface in an ovine model of acute tendon retraction, with superior mechanical and histological results associated with use of an allograft.

  3. Immediate Effects of Neurodynamic Sliding versus Muscle Stretching on Hamstring Flexibility in Subjects with Short Hamstring Syndrome

    Science.gov (United States)

    Castellote-Caballero, Yolanda; Valenza, Maríe C.; Puentedura, Emilio J.; Fernández-de-las-Peñas, César; Alburquerque-Sendín, Francisco

    2014-01-01

    Background. Hamstring injuries continue to affect active individuals and although inadequate muscle extensibility remains a commonly accepted factor, little is known about the most effective method to improve flexibility. Purpose. To determine if an isolated neurodynamic sciatic sliding technique would improve hamstring flexibility to a greater degree than stretching or a placebo intervention in asymptomatic subjects with short hamstring syndrome (SHS). Study Design. Randomized double-blinded controlled trial. Methods. One hundred and twenty subjects with SHS were randomized to 1 of 3 groups: neurodynamic sliding, hamstring stretching, and placebo control. Each subject's dominant leg was measured for straight leg raise (SLR) range of motion (ROM) before and after interventions. Data were analyzed with a 3 × 2 mixed model ANOVA followed by simple main effects analyses. Results. At the end of the study, more ROM was observed in the Neurodynamic and Stretching groups compared to the Control group and more ROM in the Neurodynamic group compared to Stretching group. Conclusion. Findings suggest that a neurodynamic sliding technique will increase hamstring flexibility to a greater degree than static hamstring stretching in healthy subjects with SHS. Clinical Relevance. The use of neurodynamic sliding techniques to improve hamstring flexibility in sports may lead to a decreased incidence in injuries; however, this needs to be formally tested. PMID:26464889

  4. The series elastic shock absorber: tendon elasticity modulates energy dissipation by muscle during burst deceleration.

    Science.gov (United States)

    Konow, Nicolai; Roberts, Thomas J

    2015-04-07

    During downhill running, manoeuvring, negotiation of obstacles and landings from a jump, mechanical energy is dissipated via active lengthening of limb muscles. Tendon compliance provides a 'shock-absorber' mechanism that rapidly absorbs mechanical energy and releases it more slowly as the recoil of the tendon does work to stretch muscle fascicles. By lowering the rate of muscular energy dissipation, tendon compliance likely reduces the risk of muscle injury that can result from rapid and forceful muscle lengthening. Here, we examine how muscle-tendon mechanics are modulated in response to changes in demand for energy dissipation. We measured lateral gastrocnemius (LG) muscle activity, force and fascicle length, as well as leg joint kinematics and ground-reaction force, as turkeys performed drop-landings from three heights (0.5-1.5 m centre-of-mass elevation). Negative work by the LG muscle-tendon unit during landing increased with drop height, mainly owing to greater muscle recruitment and force as drop height increased. Although muscle strain did not increase with landing height, ankle flexion increased owing to increased tendon strain at higher muscle forces. Measurements of the length-tension relationship of the muscle indicated that the muscle reached peak force at shorter and likely safer operating lengths as drop height increased. Our results indicate that tendon compliance is important to the modulation of energy dissipation by active muscle with changes in demand and may provide a mechanism for rapid adjustment of function during deceleration tasks of unpredictable intensity. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  5. Influence of Anterior Cruciate Ligament Tear on Thigh Muscle Strength and Hamstring-to-Quadriceps Ratio: A Meta-Analysis.

    Science.gov (United States)

    Kim, Hyun-Jung; Lee, Jin-Hyuck; Ahn, Sung-Eun; Park, Min-Ji; Lee, Dae-Hee

    2016-01-01

    Theoretical compensation after anterior cruciate ligament (ACL) tear could cause quadriceps weakness and hamstring activation, preventing anterior tibial subluxation and affecting the expected hamstring-to-quadriceps ratio. Although quadriceps weakness often occurs after ACL tears, it remains unclear whether hamstring strength and hamstring-to-quadriceps ratio increase in ACL deficient knees. This meta-analysis compared the isokinetic muscle strength of quadriceps and hamstring muscles, and the hamstring-to-quadriceps ratio, of the injured and injured limbs of patients with ACL tears. This meta-analysis included all studies comparing isokinetic thigh muscle strengths and hamstring-to-quadriceps ratio in the injured and uninjured legs of patients with ACL tear, without or before surgery. Thirteen studies were included in the meta-analysis. Quadriceps and hamstring strengths were 22.3 N∙m (95% CI: 15.2 to 29.3 N∙m; Pratio was 4% greater in ACL deficient than in uninjured limbs (95% CI: 1.7% to 6.3%; Pratio in ACL deficient knees.

  6. An anatomical and histological study of the structures surrounding the proximal attachment of the hamstring muscles.

    Science.gov (United States)

    Pérez-Bellmunt, Albert; Miguel-Pérez, Maribel; Brugué, Marc Blasi; Cabús, Juan Blasi; Casals, Martí; Martinoli, Carlo; Kuisma, Raija

    2015-06-01

    The proximal attachment of hamstring muscles has a very high incidence of injuries due to a wide number of factors and its morphology may be one of the underlying factors as scientific literature points out. The connective tissue component of the attachment of hamstring muscles is not well known. For this reason the aim of this study is to describe the anatomy and histology surrounding the proximal attachment of the hamstring muscles (PAHM) and its direct anatomic relations. Forty-eight cryopreserved lower limbs have sequentially been studied by means of dissection, anatomical sections and histology. All specimens studied presented an annular connective tissue structure that resembles a retinaculum, which covers and adapts to the attachment of hamstring muscles on the ischial tuberosity. The results show how this retinaculum is continuous with the long head of biceps femoris muscle, however there is a layer of loose connective tissue between the retinaculum and the semitendinosus muscle. Furthermore, this structure receives expansions of the anterior epimysium of the gluteus maximus muscle (GIM). Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Operative management of partial-thickness tears of the proximal hamstring muscles in athletes.

    Science.gov (United States)

    Bowman, Karl F; Cohen, Steven B; Bradley, James P

    2013-06-01

    Partial tears of the hamstring muscle origin represent a challenging clinical problem to the patient and orthopaedic surgeon. Although nonoperative treatment is frequently met with limited success, there is a paucity of data on the efficacy of surgical management for partial proximal hamstring tears in the active and athletic population. To evaluate the results of an anatomic repair for partial tears of the hamstring muscle origin in athletes. Case series; Level of evidence, 4. The records of 17 patients with partial tears of the proximal hamstring origin were reviewed after institutional review board approval was obtained. All patients were treated with open debridement and primary tendon repair after failure of at least 6 months of nonoperative therapy. Clinical and operative records, radiographs, and magnetic resonance images were reviewed for all patients. A patient-reported outcomes survey was completed by 14 patients that included the Lower Extremity Functional Score (LEFS), Marx activity rating scale, custom LEFS and Marx scales, and subjective patient satisfaction scores. Early and late postoperative complications were recorded. There were 3 male and 14 female patients; their average age was 43 years (range, 19-64 years) and average follow-up was 32 months (range, 12-51 months). There were 2 collegiate athletes (field hockey, track), 14 amateur athletes (distance running, waterskiing, tennis), and a professional bodybuilder. Postoperative LEFS was 73.3 ± 9.9 (range, 50-80) and custom LEFS was 66.7 ± 17.0 (range, 37-80) of a maximum 80 points. The most commonly reported difficulty was with prolonged sitting and explosive direction change while running. The average Marx score was 6.5 ± 5.3 (range, 0-16) of a maximum 16, correlating with a greater return to recreational running activities in this patient cohort than regular participation in pivoting or cutting sports. Marx custom scores were 20 of a maximum 20 in all patients, demonstrating no disability in

  8. The functional muscle-bone unit in children with cerebral palsy.

    Science.gov (United States)

    Duran, I; Schütz, F; Hamacher, S; Semler, O; Stark, C; Schulze, J; Rittweger, J; Schoenau, E

    2017-07-01

    Our results suggest that the prevalence of bone health deficits in children with CP was overestimated, when using only age- and height-adjusted bone mineral content (BMC) and areal bone mineral density (aBMD). When applying the functional muscle-bone unit diagnostic algorithm (FMBU-A), the prevalence of positive results decreased significantly. We recommend applying the FMBU-A when assessing bone health in children with CP. The prevalence of bone health deficits in children with cerebral palsy (CP) might be overestimated because age- and height-adjusted reference percentiles for bone mineral content (BMC) and areal bone mineral density (aBMD) assessed by dual-energy X-ray absorptiometry (DXA) do not consider reduced muscle activity. The aim of this study was to compare the prevalence of positive DXA-based indicators for bone health deficits in children with CP to the prevalence of positive findings after applying a functional muscle-bone unit diagnostic algorithm (FMBU-A) considering reduced muscle activity. The present study was a monocentric retrospective analysis of 297 whole body DXA scans of children with CP. The prevalence of positive results of age- and height-adjusted BMC and aBMD defined as BMC and aBMD below the P3 percentile and of the FMBU-A was calculated. In children with CP, the prevalence of positive results of age-adjusted BMC were 33.3% and of aBMD 50.8%. Height-adjusted results for BMC and aBMD were positive in 16.8 and 36.0% of cases. The prevalence of positive results applying the FMBU-A regarding BMC and aBMD were significantly (p BMC and aBMD (8.8 and 14.8%). Our results suggest that the prevalence of bone health deficits in children with CP was overestimated, when using age- and height-adjusted BMC and aBMD. When applying the FMBU-A, the prevalence decreased significantly. We recommend applying the FMBU-A when assessing bone health in children with CP.

  9. DEVELOPMENTS IN THE USE OF THE HAMSTRING/QUADRICEPS RATIO FOR THE ASSESSMENT OF MUSCLE BALANCE

    Directory of Open Access Journals (Sweden)

    Gerard Garbutt

    2002-09-01

    Full Text Available Isokinetic moment ratios of the hamstrings (H and quadriceps (Q muscle groups, and their implication in muscle imbalance, have been investigated for more than three decades. The conventional concentric H/Q ratio with its normative value of 0.6 has been at the forefront of the discussion. This does not account for the joint angle at which moment occurs and the type of muscle action involved. Advances towards more functional analyses have occurred such that previous protocols are being re-examined raising questions about their ability to demonstrate a relationship between thigh muscle imbalance and increased incidence or risk of knee injury. This article addresses the function of the hamstring-quadriceps ratio in the interpretation of this relationship using the ratios Hecc/Qcon (ratio of eccentric hamstring strength to concentric quadriceps strength, representative of isolated knee extension and Hcon/Qecc (ratio of concentric hamstring strength to eccentric quadriceps strength, representative of isolated knee flexion.

  10. Influence of Anterior Cruciate Ligament Tear on Thigh Muscle Strength and Hamstring-to-Quadriceps Ratio: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Hyun-Jung Kim

    Full Text Available Theoretical compensation after anterior cruciate ligament (ACL tear could cause quadriceps weakness and hamstring activation, preventing anterior tibial subluxation and affecting the expected hamstring-to-quadriceps ratio. Although quadriceps weakness often occurs after ACL tears, it remains unclear whether hamstring strength and hamstring-to-quadriceps ratio increase in ACL deficient knees. This meta-analysis compared the isokinetic muscle strength of quadriceps and hamstring muscles, and the hamstring-to-quadriceps ratio, of the injured and injured limbs of patients with ACL tears. This meta-analysis included all studies comparing isokinetic thigh muscle strengths and hamstring-to-quadriceps ratio in the injured and uninjured legs of patients with ACL tear, without or before surgery. Thirteen studies were included in the meta-analysis. Quadriceps and hamstring strengths were 22.3 N∙m (95% CI: 15.2 to 29.3 N∙m; P<0.001 and 7.4 N∙m (95% CI: 4.3 to 10.5 N∙m; P<0.001 lower, respectively, on the injured than on the uninjured side. The mean hamstring-to-quadriceps ratio was 4% greater in ACL deficient than in uninjured limbs (95% CI: 1.7% to 6.3%; P<0.001. Conclusively, Decreases were observed in both the quadriceps and hamstring muscles of patients with ACL tear, with the decrease in quadriceps strength being 3-fold greater. These uneven reductions slightly increase the hamstring-to-quadriceps ratio in ACL deficient knees.

  11. The effects of surgical lengthening of hamstring muscles in children with cerebral palsy--the consequences of pre-operative muscle length measurement.

    Science.gov (United States)

    Laracca, Ettore; Stewart, Caroline; Postans, Neil; Roberts, Andrew

    2014-03-01

    Children with cerebral palsy often undergo multiple orthopaedic surgical procedures in a single episode. Evidence of the effectiveness of individual components within the overall package is sparse. The introduction of musculoskeletal modelling in Oswestry has led to a more conservative management approach being taken with hamstring muscles for children walking in a degree of crouch. Muscles which were shown to be of at least normal length at initial contact were not surgically lengthened, as would have been the case previously. A retrospective review of 30 such patients was therefore possible, comparing 15 patients treated before the policy change who had their hamstrings lengthened with 15 treated after who did not. All patients had pre and post operative gait assessments and significant changes were observed for each group separately and for the two groups when compared. The comparison revealed that preserving the hamstrings does tend to reduce, and therefore normalize, the dynamic muscle length. Examination of the two patient groups separately, however, reveals a more complex picture with more global gait improvements seen when the hamstrings were lengthened. No absolute recommendation can be made to inform the clinical management of all children with normal to long hamstring muscles during gait. The final decision of whether to include a hamstring lengthening will need to take into account the characteristics of the individual child. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Patterns of Hamstring Muscle Tears in the General Population: A Systematic Review.

    Science.gov (United States)

    Kuske, Barbara; Hamilton, David F; Pattle, Sam B; Simpson, A Hamish R W

    2016-01-01

    Hamstring tears are well recognised in the sporting population. Little is known about these injuries in the general population. Evaluating the rates, patterns and risk factors of non-sporting hamstring tears, compared to sporting related hamstring tears. MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials (1989-2015). Studies reporting patients with a grade 2 or 3 hamstring muscle tear, identified clinically, confirmed by MRI imaging or direct visualisation during surgical exploration. 144 sets of linked data were extracted for analysis. Most injuries were in males (81.3%), where mean age at injury was lower (30.2, 95% CI 29.1-31.3) than in females (35.4, 95% CI 32.4-38.4) p = 0.06. Key differences were found in the proportion of non-sporting injuries in patients under and over the age 40 (p = 0.001). The proportion of non-sporting injuries was significantly higher in females compared to males (25.9% female non-sporting injuries, versus 8.5% male; p = 0.02). Avulsions were more frequently reported in non-sporting activities (70.5%). The proportion of such injuries was notably higher in females, though this failed to meet significance (p = 0.124). Grouped by age category a bimodal distribution was noted, with the proportion of avulsions greater in younger (age 40) (p = 0.008). 86.8% of patients returned to pre-injury activity levels with a similar frequency across all study variables; age, activity (sporting vs non-sporting) and injury type (avulsion vs tear). This review highlights a proportion of adults suffering grade 2 or 3 hamstring injuries from activities other than the classic sports trauma. The majority of these non-sporting injuries were avulsion injuries that clustered in older female and skeletally immature patients suggesting a potential link to bone mineral density.

  13. Patterns of Hamstring Muscle Tears in the General Population: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Barbara Kuske

    Full Text Available Hamstring tears are well recognised in the sporting population. Little is known about these injuries in the general population.Evaluating the rates, patterns and risk factors of non-sporting hamstring tears, compared to sporting related hamstring tears.MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials (1989-2015.Studies reporting patients with a grade 2 or 3 hamstring muscle tear, identified clinically, confirmed by MRI imaging or direct visualisation during surgical exploration.144 sets of linked data were extracted for analysis. Most injuries were in males (81.3%, where mean age at injury was lower (30.2, 95% CI 29.1-31.3 than in females (35.4, 95% CI 32.4-38.4 p = 0.06. Key differences were found in the proportion of non-sporting injuries in patients under and over the age 40 (p = 0.001. The proportion of non-sporting injuries was significantly higher in females compared to males (25.9% female non-sporting injuries, versus 8.5% male; p = 0.02. Avulsions were more frequently reported in non-sporting activities (70.5%. The proportion of such injuries was notably higher in females, though this failed to meet significance (p = 0.124. Grouped by age category a bimodal distribution was noted, with the proportion of avulsions greater in younger (age 40 (p = 0.008. 86.8% of patients returned to pre-injury activity levels with a similar frequency across all study variables; age, activity (sporting vs non-sporting and injury type (avulsion vs tear.This review highlights a proportion of adults suffering grade 2 or 3 hamstring injuries from activities other than the classic sports trauma. The majority of these non-sporting injuries were avulsion injuries that clustered in older female and skeletally immature patients suggesting a potential link to bone mineral density.

  14. Medial gastrocnemius and soleus muscle-tendon unit, fascicle, and tendon interaction during walking in children with cerebral palsy.

    Science.gov (United States)

    Barber, Lee; Carty, Chris; Modenese, Luca; Walsh, John; Boyd, Roslyn; Lichtwark, Glen

    2017-08-01

    This study investigates the in vivo function of the medial gastrocnemius and soleus muscle-tendon units (MTU), fascicles, and tendons during walking in children with cerebral palsy (CP) and an equinus gait pattern. Fourteen children with CP (9 males, 5 females; mean age 10y 6mo, standard deviation [SD] 2y 11mo; GMFCS level I=8, II=6), and 10 typically developing (6 males, 4 females; mean age 10y, SD 2y 1mo) undertook full body 3D gait analysis and simultaneous B-mode ultrasound images of the medial gastrocnemius and soleus fascicles during level walking. Fascicle lengths were analysed using a semi-automated tracking algorithm and MTUs using OpenSim. Statistical parametric mapping (two-sample t-test) was used to compare differences between groups (ppower during push-off (p=0.015) and positive work (ppower and positive work in the children with CP may be attributed to reduced active medial gastrocnemius fascicle shortening. These findings suggest a reliance on passive force generation for forward propulsion during equinus gait. © 2017 Mac Keith Press.

  15. Anabolic Steroids Reduce Muscle Degeneration Associated With Rotator Cuff Tendon Release in Sheep.

    Science.gov (United States)

    Gerber, Christian; Meyer, Dominik C; Flück, Martin; Benn, Mario C; von Rechenberg, Brigitte; Wieser, Karl

    2015-10-01

    Chronic rotator cuff tendon tearing is associated with irreversible atrophy, fatty infiltration, and interstitial fibrosis of the corresponding muscle. Anabolic steroids can prevent musculotendinous degeneration during retraction and/or can reverse these changes after operative repair of the retracted musculotendinous unit in sheep. Controlled laboratory study. The infraspinatus tendon was released in 18 alpine sheep. All sheep underwent repair of the retracted musculotendinous unit after 16 weeks and were sacrificed after 22 weeks; 6 sheep served as controls, 6 sheep were treated with weekly intramuscular injection of 150 mg of nandrolone decanoate after infraspinatus (ISP) repair (group N6W), and 6 sheep were treated with 150 mg of nandrolone decanoate immediately after tendon release (group N22W). Muscle biopsy specimens were taken before tendon release and after 16 and 22 weeks. Muscle volume and fatty infiltration (on MRI), myotendinous retraction, and muscle density (on computed tomography) were measured immediately after ISP release, after 6 weeks, and before ISP repair and sacrifice. Muscle volume on MRI decreased to a mean (±SD) of 80% ± 8% of the original volume after 6 weeks, remained stable at 78% ± 11% after 16 weeks, and decreased further to 69% ± 9% after 22 weeks in the control group. These findings were no different from those in group N22W (72% ± 9% at 6 weeks, 73% ± 6% at 16 weeks, and 67% ± 5% at 22 weeks). Conversely, the N6W group did not show a decrease in ISP volume after repair; this finding differed significantly from the response in the control and N22W groups. Fatty infiltration (on MRI) continuously increased in the control group (12% ± 4% at tendon release, 17% ± 4% after 6 weeks, 50% ± 9% after 16 weeks, and 60% ± 8% after 22 weeks) and the N6W group. However, application of anabolic steroids at the time of tendon release (N22W group) significantly reduced fatty infiltration after 16 (16% ± 5%; P anabolic steroids starting

  16. Individual Muscle use in Hamstring Exercises by Soccer Players Assessed using Functional MRI.

    Science.gov (United States)

    Fernandez-Gonzalo, R; Tesch, P A; Linnehan, R M; Kreider, R B; Di Salvo, V; Suarez-Arrones, L; Alomar, X; Mendez-Villanueva, A; Rodas, G

    2016-06-01

    This study used functional magnetic resonance imaging (fMRI) to compare individual muscle use in exercises aimed at preventing hamstring injuries. Thirty-six professional soccer players were randomized into 4 groups, each performing either Nordic hamstring, flywheel leg curl, Russian belt or conic-pulley exercise. MRIs were performed before and immediately after a bout of 4 sets of 8 repetitions. Pre-post exercise differences in contrast shift (T2) were analyzed for the long (BFLh) and short head (BFSh) of biceps femoris, semitendinosus (ST), semimembranosus (SM) and gracilis (GR) muscles. Flywheel leg curl increased (Phamstring, GR (39%), ST (16%) and BFSh (14%) showed increased T2 (Phamstring and GR muscle use. However, no single exercise executed was able to increase T2 of all hamstring and synergist muscles analyzed. It is therefore suggested that multiple exercises must be carried out to bring in, and fully activate all knee flexors and hip extensors. © Georg Thieme Verlag KG Stuttgart · New York.

  17. The development and morphogenesis of the tendon-to-bone insertion What development can teach us about healing

    Science.gov (United States)

    Thomopoulos, Stavros; Genin, Guy M.; Galatz, Leesa M.

    2013-01-01

    The attachment of dissimilar materials is a major challenge because of the high levels of stress that develop at such interfaces. An effective solution to this problem develops at the attachment of tendon (a compliant “soft tissue”) to bone (a stiff “hard tissue”). This tissue, the “enthesis”, transitions from tendon to bone through gradations in structure, composition, and mechanical properties. These gradations are not regenerated during tendon-to-bone healing, leading to a high incidence of failure after surgical repair. Understanding the development of the enthesis may allow scientists to develop treatments that regenerate the natural tendon-to-bone insertion. Recent work has demonstrated that both biologic and mechanical factors drive the development and morphogenesis of the enthesis. A cascade of biologic signals similar to those seen in the growth plate promotes mineralization of cartilage on the bony end of the enthesis and the formation of fibrocartilage on the tendon end of the enthesis. Mechanical loading is also necessary for the development of the enthesis. Removal of muscle load impairs the formation of bone, fibrocartilage, and tendon at the developing enthesis. This paper reviews recent work on the development of the enthesis, with an emphasis on the roles of biologic and mechanical factors. PMID:20190378

  18. Immediate Effects of Neurodynamic Sliding versus Muscle Stretching on Hamstring Flexibility in Subjects with Short Hamstring Syndrome

    Directory of Open Access Journals (Sweden)

    Yolanda Castellote-Caballero

    2014-01-01

    Full Text Available Background. Hamstring injuries continue to affect active individuals and although inadequate muscle extensibility remains a commonly accepted factor, little is known about the most effective method to improve flexibility. Purpose. To determine if an isolated neurodynamic sciatic sliding technique would improve hamstring flexibility to a greater degree than stretching or a placebo intervention in asymptomatic subjects with short hamstring syndrome (SHS. Study Design. Randomized double-blinded controlled trial. Methods. One hundred and twenty subjects with SHS were randomized to 1 of 3 groups: neurodynamic sliding, hamstring stretching, and placebo control. Each subject’s dominant leg was measured for straight leg raise (SLR range of motion (ROM before and after interventions. Data were analyzed with a 3×2 mixed model ANOVA followed by simple main effects analyses. Results. At the end of the study, more ROM was observed in the Neurodynamic and Stretching groups compared to the Control group and more ROM in the Neurodynamic group compared to Stretching group. Conclusion. Findings suggest that a neurodynamic sliding technique will increase hamstring flexibility to a greater degree than static hamstring stretching in healthy subjects with SHS. Clinical Relevance. The use of neurodynamic sliding techniques to improve hamstring flexibility in sports may lead to a decreased incidence in injuries; however, this needs to be formally tested.

  19. Association between maximal hamstring muscle strength and hamstring muscle pre-activity during a movement associated with non-contact ACL injury

    DEFF Research Database (Denmark)

    Zebis, M. K.; Sorensen, R. S.; Thorborg, K.

    2015-01-01

    Background: Reduced hamstring pre-activity during sidecutting increases the risk for non-contact ACL injury. During the last decade resistance training of the lower limb muscles has become an integral part ofACLinjury prevention in e.g. soccer and handball. However, it is not known whether a stro...

  20. Intramuscular tendon involvement on MRI has limited value for predicting time to return to play following acute hamstring injury

    NARCIS (Netherlands)

    van der Made, Anne D.; Almusa, Emad; Whiteley, Rod; Hamilton, Bruce; Eirale, Cristiano; van Hellemondt, Frank; Tol, Johannes L.

    2018-01-01

    Background Hamstring injury with intramuscular tendon involvement is regarded as a serious injury with a delay in return to play (RTP) of more than 50 days and reinjury rates up to 63%. However, this reputation is based on retrospective case series with high risk of bias. Objective Determine whether

  1. The relationship between hamstring length and gluteal muscle strength in individuals with sacroiliac joint dysfunction

    OpenAIRE

    Massoud Arab, Amir; Reza Nourbakhsh, Mohammad; Mohammadifar, Ali

    2011-01-01

    It has been suggested that tight hamstring muscle, due to its anatomical connections, could be a compensatory mechanism for providing sacroiliac (SI) joint stability in patients with gluteal muscle weakness and SIJ dysfunction. The purpose of this study was to determine the relationship between hamstring muscle length and gluteal muscle strength in subjects with sacroiliac joint dysfunction. A total of 159 subjects with and without low back pain (LBP) between the ages of 20 and 65 years parti...

  2. Influence of hamstring muscles extensibility on spinal curvatures and pelvic tilt in highly trained cyclists.

    Science.gov (United States)

    Muyor, José M; Alacid, Fernando; López-Miñarro, Pedro A

    2011-09-01

    The purpose of this study was to determine the influence of hamstring muscles extensibility in standing, maximal trunk flexion with knees extended and on the bicycle in lower handlebar-hands position of highly trained cyclists. Ninety-six cyclists were recruited for the study (mean ± SD, age: 30.36 ± 5.98 years). Sagittal spinal curvatures and pelvic tilt were measured in the standing position, maximal trunk flexion with knees extended (sit-and-reach test) and while sitting on a bicycle in lower handlebar-hand position using a Spinal Mouse system. Hamstring muscles extensibility was determined in both legs by passive straight leg raise test (PSLR). The sample was divided into three groups according to PSLR angle: (1) reduced extensibility (PSLR hamstring extensibility group (PSLR = 80º - 90º; n = 35), and (3) high hamstring extensibility (PSLR = > 90º; n = 31). ANOVA analysis showed significant differences among groups for thoracic (p hamstring muscles extensibility influence the thoracic and pelvic postures when maximal trunk flexion with knees extended is performed, but not when cyclists are seated on their bicycles.

  3. Extensor Tendon Injuries

    Science.gov (United States)

    ... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy Extensor Tendon Injuries Email to a friend * required ...

  4. Expression of collagen and related growth factors in rat tendon and skeletal muscle in response to specific contraction types

    DEFF Research Database (Denmark)

    Heinemeier, K M; Olesen, J L; Haddad, F

    2007-01-01

    greater than the effect of concentric training on the expression of several transcripts. In conclusion, the study supports an involvement of TGF-beta-1 in loading-induced collagen synthesis in the muscle-tendon unit and importantly, it indicates that muscle tissue is more sensitive than tendon......Acute exercise induces collagen synthesis in both tendon and muscle, indicating an adaptive response in the connective tissue of the muscle-tendon unit. However, the mechanisms of this adaptation, potentially involving collagen-inducing growth factors (such as transforming growth factor-beta-1 (TGF......-beta-1)), as well as enzymes related to collagen processing, are not clear. Furthermore, possible differential effects of specific contraction types on collagen regulation have not been investigated. Female Sprague-Dawley rats were subjected to 4 days of concentric, eccentric or isometric training (n = 7...

  5. Muscle-tendon mechanics explain unexpected effects of exoskeleton assistance on metabolic rate during walking.

    Science.gov (United States)

    Jackson, Rachel W; Dembia, Christopher L; Delp, Scott L; Collins, Steven H

    2017-06-01

    The goal of this study was to gain insight into how ankle exoskeletons affect the behavior of the plantarflexor muscles during walking. Using data from previous experiments, we performed electromyography-driven simulations of musculoskeletal dynamics to explore how changes in exoskeleton assistance affected plantarflexor muscle-tendon mechanics, particularly for the soleus. We used a model of muscle energy consumption to estimate individual muscle metabolic rate. As average exoskeleton torque was increased, while no net exoskeleton work was provided, a reduction in tendon recoil led to an increase in positive mechanical work performed by the soleus muscle fibers. As net exoskeleton work was increased, both soleus muscle fiber force and positive mechanical work decreased. Trends in the sum of the metabolic rates of the simulated muscles correlated well with trends in experimentally observed whole-body metabolic rate ( R 2 =0.9), providing confidence in our model estimates. Our simulation results suggest that different exoskeleton behaviors can alter the functioning of the muscles and tendons acting at the assisted joint. Furthermore, our results support the idea that the series tendon helps reduce positive work done by the muscle fibers by storing and returning energy elastically. We expect the results from this study to promote the use of electromyography-driven simulations to gain insight into the operation of muscle-tendon units and to guide the design and control of assistive devices. © 2017. Published by The Company of Biologists Ltd.

  6. Susceptibility to Hamstring Injuries in Soccer: A Prospective Study Using Muscle Functional Magnetic Resonance Imaging.

    Science.gov (United States)

    Schuermans, Joke; Van Tiggelen, Damien; Danneels, Lieven; Witvrouw, Erik

    2016-05-01

    Running-related hamstring strain injuries remain a delicate issue in several sports such as soccer. Their unremittingly high incidence and recurrence rates indicate that the underlying risk has not yet been fully identified. Among other factors, the importance of neuromuscular coordination and the quality of interplay between the different hamstring muscle bellies is thought to be a key determinant within the intrinsic injury risk. Muscle functional magnetic resonance imaging (mfMRI) is one of the tools that has been proven to be valid for evaluating intermuscular coordination. To investigate the risk of sustaining an index or recurring soccer-related hamstring injury by exploring metabolic muscle characteristics using mfMRI. Cohort study; Level of evidence, 2. A total of 27 healthy male soccer players and 27 soccer players with a history of hamstring injuries underwent standardized mfMRI. The mfMRI protocol consisted of a resting scan, a strenuous bilateral eccentric hamstring exercise, and a postexercise scan. The exercise-related T2 change, or the signal intensity shift between both scans, was used to detect differences in metabolic characteristics between (1) the different hamstring muscle bellies and (2) the prospective cohorts based on the (re)occurrence of hamstring injuries during a follow-up period of 18 months. The risk of sustaining a first hamstring injury was associated with alterations in the intermuscular hierarchy in terms of the magnitude of the metabolic response after a heavy eccentric effort, with the dominant role of the semitendinosus set aside for a higher contribution of the biceps femoris (P = .017). Receiver operating characteristic (ROC) curve analysis demonstrated that this variable was significantly able to predict the occurrence of index injuries with a sensitivity of 100% and a specificity of 70% when the metabolic activity of the biceps femoris exceeded 10%. The risk of sustaining a reinjury was associated with a substantial deficit

  7. MRI-Based Regional Muscle Use during Hamstring Strengthening Exercises in Elite Soccer Players.

    Science.gov (United States)

    Mendez-Villanueva, Alberto; Suarez-Arrones, Luis; Rodas, Gil; Fernandez-Gonzalo, Rodrigo; Tesch, Per; Linnehan, Richard; Kreider, Richard; Di Salvo, Valter

    2016-01-01

    The present study examined site-specific hamstring muscles use with functional magnetic resonance imaging (MRI) in elite soccer players during strength training. Thirty-six players were randomized into four groups, each performing either Nordic hamstring, flywheel leg-curl, Russian belt or the hip-extension conic-pulley exercise. The transverse relaxation time (T2) shift from pre- to post-MRI were calculated for the biceps femoris long (BFl) and short (BFs) heads, semitendinosus (ST) and semimembranosus (SM) muscles at proximal, middle and distal areas of the muscle length. T2 values increased substantially after flywheel leg-curl in all regions of the BFl (from 9±8 to 16±8%), BFs (41±6-71±11%), and ST (60±1-69±7%). Nordic hamstring induced a substantial T2 increase in all regions of the BFs (13±8-16±5%) and ST (15±7-17±5%). T2 values after the Russian belt deadlift substantially increased in all regions of the BFl (6±4-7±5%), ST (8±3-11±2%), SM (6±4-10±4%), and proximal and distal regions of BFs (6±6-8±5%). T2 values substantially increased after hip-extension conic-pulley only in proximal and middle regions of BFl (11±5-7±5%) and ST (7±3-12±4%). The relevance of such MRI-based inter- and intra-muscle use in designing more effective resistance training for improving hamstring function and preventing hamstring injuries in elite soccer players should be explored with more mechanistic studies.

  8. Biceps femoris and semitendinosus—teammates or competitors? New insights into hamstring injury mechanisms in male football players: a muscle functional MRI study

    Science.gov (United States)

    Schuermans, Joke; Van Tiggelen, Damien; Danneels, Lieven; Witvrouw, Erik

    2014-01-01

    Background The hamstring injury mechanism was assessed by investigating the exercise-related metabolic activity characteristics of the hamstring muscles using a muscle functional MRI (mfMRI) protocol. Methods 27 healthy male football players and 27 football players with a history of hamstring injuries (recovered and playing fully) underwent standardised mfMR Imaging. The mfMRI protocol consisted of a resting scan, a strenuous bilateral eccentric hamstring exercise and a postexercise scan. The exercise-related T2 increase or the signal intensity shift between both scans was used to detect differences in metabolic activation characteristics (1) between the different hamstring muscle bellies and (2) between the injury group and the control group. Results A more symmetrical muscle recruitment pattern corresponding to a less economic hamstring muscle activation was demonstrated in the formerly injured group (phamstring exercise. Conclusions These findings suggest that the vulnerability of the hamstring muscles to football-related injury is related to the complexity and close coherence in the synergistic muscle recruitment of the biceps femoris and the semitendinosus. Discrete differences in neuromuscular coordination and activity distribution, with the biceps femoris partly having to compensate for the lack of endurance capacity of the semitendinosus, probably increase the hamstring injury risk. PMID:25388959

  9. Press-fit Femoral Fixation in ACL Reconstruction using Bone-Patellar Tendon-Bone Graft

    Directory of Open Access Journals (Sweden)

    Kaseb Mohammad Hasan

    2009-05-01

    Full Text Available Bone-patellar tendon auto graft is probably the most widely used graft for ACL reconstruction. Several methods for graft fixation have been described. To avoid intra-articular hardware we adopt biological fixation with a femoral trapezoidal press-fit fixation. A prospective study was performed on 30 consecutive active people who underwent ACL reconstruction with this technique by two surgeons between september2004 and march2007 (mean follow-up 15.2 months. Results were evaluated by an independent examiner using radiography, subjective and objective evaluation. Assessment using the IKDC knee scoring revealed 92% of the patients with a normal or nearly normal knee joint. Lysholm's score was 63.6(40- 86 preoperatively and 91.88(73-100 at the latest follow up (P < 0.005. No patient complained of instability at latest follow up. The quadriceps muscle showed mild atrophy at 3 and 6 months and at final follow-up. Five Patients complained of anterior knee pain and had a positive kneeling test. We found no graft displacement on follow up radiographs. All cases showed radiological evidence of graft osteointegration at last follow up. Our results show that press-fit fixation of trapezoidal bone graft in femoral tunnel is a simple, reliable, and cost-effective alternative for ACL recon-struction using bone-patellar tendon-bone graft.

  10. A comparison of hamstring muscle activity during different screening tests for non-contact ACL injury.

    Science.gov (United States)

    Husted, Rasmus S; Bencke, Jesper; Andersen, Lars L; Myklebust, Grethe; Kallemose, Thomas; Lauridsen, Hanne B; Hölmich, Per; Aagaard, Per; Zebis, Mette K

    2016-06-01

    Reduced ability to activate the medial hamstring muscles during a sports-specific sidecutting movement has been found to be a potential risk factor for non-contact ACL injury. However, whether a reduced ability to activate the medial hamstring muscle is a general neuromuscular phenomenon and thereby observable independently of the type of clinical screening tests used is not known. This cross sectional study investigated the rank correlation of knee joint neuromuscular activity between three different ACL injury risk screening tests. Sixty-two adolescent female elite football and handball players (16.7±1.3years) participated in the study. Using surface electromyography (EMG) assessment, the neuromuscular activity of medial hamstring muscle (semitendinosus, ST), lateral hamstring muscle (biceps femoris, BF) and quadriceps muscle (vastus lateralis, VL) were monitored during three standardized screening tests - i.e. one-legged horizontal hop (OLH), drop vertical jump (DJ) and sidecutting (SC). Neuromuscular pre-activity was measured in the time interval 10ms prior to initial contact on a force plate. For neuromuscular hamstring muscle pre-activity, correlation analysis (Spearman correlation coefficient) showed low-to-moderate correlations between SC and 1) DJ (rs=0.34-0.36, Phamstring pre-activity share some common variance during the examined tests. However, a lack of strong correlation suggests that we cannot generalize one risk factor during one test to another test. The present data demonstrate that one-legged horizontal hop and drop vertical jump testing that are commonly used in the clinical setting does not resemble the specific neuromuscular activity patterns known to exist during sidecutting, a well known high risk movement for non-contact ACL injury. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. COMPARATIVE EFFECT OF STATIC AND DYNAMIC STRETCHING EXERCISE TO IMPROVE FLEXIBILITY OF HAMSTRING MUSCLES AMONG NON ATHLETES

    Directory of Open Access Journals (Sweden)

    Jibi Paul

    2014-10-01

    Full Text Available Background: Stretching exercises have been routinely used in persons with hamstring tightness and athletes to increase flexibility of muscle and to reduce joint injuries. Many studies have reported effect of static and dynamic stretching on flexibility of this muscle. Finding the best method to improve flexibility of hamstring muscle is important for athletes and individuals to reduce their injuries. Objective of the study was to find out the effect of static stretching exercise and dynamic stretching exercise on flexibility of hamstring muscle and also to compare the effect of static and dynamic stretching exercise on flexibility of hamstring muscle. Methods: This was a comparative experimental study with seventy four female healthy subjects from physiotherapy department of KPJ Healthcare University College, Malaysia. Convenient sampling method used to select the samples. The subjects were selected by inclusion criteria and randomly divided equally in to two with 37 subjects in each group. Static stretching exercise and dynamic stretching exercise were given as intervention program for four weeks respectively for experimental and control group. Pre and post data of restricted range of movement for knee extension was measured using goniometry and documented separately for both group. Result: In experimental and control group, pre-post statistical analysis found significant effect in increase of hamstring flexibility with P<0.0001, for right and left side. Comparative study between experimental and control group found that static stretching exercise have significant effect in increase of hamstring flexibility for right and left side with P<0.04. Conclusion: This study concluded that static stretching exercise is more effective to improve hamstring flexibility compared to dynamic stretching exercise.

  12. Low back pain, radiculopathy, and bilateral proximal hamstring ruptures: a case report.

    Science.gov (United States)

    Deren, Matthew E; DeFroda, Steven F; Mukand, Nita H; Mukand, Jon A

    2015-12-01

    Low back pain (LBP) is a common complaint in the United States, with an incidence of 6.3%-15.4% and yearly recurrence in 54%-90% of patients.1 Trends show more frequent diagnostic testing, opioid use, and surgical intervention as the incidence of LBP increases.2 LBP is defined as pain at and near the lumbosacral region that can vary with physical activity and time. LBP is usually related to pathology of muscles, ligaments, spinal column joints, nerve roots, and the spinal cord. During the assessment of LBP, practitioners must also consider less common causes of pain in that region. For instance, patients with indolent or nighttime pain may have infectious or malignant processes. Referred pain from injuries to pelvic musculature or abdominal contents should be considered, especially following a traumatic event. One of these injuries, which can present as acute low back pain, is rupture of the proximal hamstring tendon. On rare occasion, concomitant LBP, radiculopathy, and hamstring injuries can occur;. This diagnostic challenge is described in the following case.

  13. A Tendon Cell Specific RNAi Screen Reveals Novel Candidates Essential for Muscle Tendon Interaction.

    Directory of Open Access Journals (Sweden)

    Prabhat Tiwari

    Full Text Available Tendons are fibrous connective tissue which connect muscles to the skeletal elements thus acting as passive transmitters of force during locomotion and provide appropriate body posture. Tendon-derived cues, albeit poorly understood, are necessary for proper muscle guidance and attachment during development. In the present study, we used dorsal longitudinal muscles of Drosophila and their tendon attachment sites to unravel the molecular nature of interactions between muscles and tendons. We performed a genetic screen using RNAi-mediated knockdown in tendon cells to find out molecular players involved in the formation and maintenance of myotendinous junction and found 21 candidates out of 2507 RNAi lines screened. Of these, 19 were novel molecules in context of myotendinous system. Integrin-βPS and Talin, picked as candidates in this screen, are known to play important role in the cell-cell interaction and myotendinous junction formation validating our screen. We have found candidates with enzymatic function, transcription activity, cell adhesion, protein folding and intracellular transport function. Tango1, an ER exit protein involved in collagen secretion was identified as a candidate molecule involved in the formation of myotendinous junction. Tango1 knockdown was found to affect development of muscle attachment sites and formation of myotendinous junction. Tango1 was also found to be involved in secretion of Viking (Collagen type IV and BM-40 from hemocytes and fat cells.

  14. Reversibility of Supraspinatus Muscle Atrophy in Tendon-Bone Healing After Arthroscopic Rotator Cuff Repair.

    Science.gov (United States)

    Park, Yong Bok; Ryu, Ho Young; Hong, Jin Ho; Ko, Young Hoo; Yoo, Jae Chul

    2016-04-01

    To date, there are few reports of the definite reversibility of rotator cuff muscle atrophy after repair. To evaluate the reversibility of rotator cuff muscle atrophy after successful arthroscopic repair. Case series; Level of evidence, 4. Included in this study were 47 patients (mean age, 61.2 ± 7.3 years; range, 49-73 years) who underwent arthroscopic rotator cuff repair as well as magnetic resonance imaging (MRI) preoperatively and at 6-month and last follow-up. Patients who had confirmed rotator cuff healing (grades 1-3 according to the Sugaya classification) on both series of postoperative MRI were enrolled in the study. The mean time from the onset of symptoms to surgery was 24.7 ± 25.6 months (range, 3-120 months). The minimum follow-up was 2 years, and the mean follow-up duration was 41.8 ± 14.4 months. Serial changes in the supraspinatus muscle area on the most matching MRI scans (sagittal-oblique view) were evaluated. The area was measured by 2 independent observers. Both independent observers reported no significant difference in the area of the supraspinatus muscle between the preoperative time point and 6-month follow-up (observer 1: P = .135; observer 2: P = .189). However, there was a significant difference between the 6-month and last follow-up (mean, 41.8 months; observers 1 and 2: P .999) or from 6-month to final follow-up (P = .077). After successful arthroscopic rotator cuff repair, there was a slight (11.3%-13.9%) increase in muscle volume from preoperatively to final follow-up, as seen on serial MRI. Fatty infiltration according to the Goutallier grade was not reversed (P = .077). Some reversibility of supraspinatus muscle atrophy may exist in tendon-bone healing after arthroscopic rotator cuff repair; further follow-up is needed to better elucidate this result. © 2016 The Author(s).

  15. Biceps femoris and semitendinosus--teammates or competitors? New insights into hamstring injury mechanisms in male football players: a muscle functional MRI study.

    Science.gov (United States)

    Schuermans, Joke; Van Tiggelen, Damien; Danneels, Lieven; Witvrouw, Erik

    2014-12-01

    The hamstring injury mechanism was assessed by investigating the exercise-related metabolic activity characteristics of the hamstring muscles using a muscle functional MRI (mfMRI) protocol. 27 healthy male football players and 27 football players with a history of hamstring injuries (recovered and playing fully) underwent standardised mfMR Imaging. The mfMRI protocol consisted of a resting scan, a strenuous bilateral eccentric hamstring exercise and a postexercise scan. The exercise-related T2 increase or the signal intensity shift between both scans was used to detect differences in metabolic activation characteristics (1) between the different hamstring muscle bellies and (2) between the injury group and the control group. A more symmetrical muscle recruitment pattern corresponding to a less economic hamstring muscle activation was demonstrated in the formerly injured group (phamstring exercise. These findings suggest that the vulnerability of the hamstring muscles to football-related injury is related to the complexity and close coherence in the synergistic muscle recruitment of the biceps femoris and the semitendinosus. Discrete differences in neuromuscular coordination and activity distribution, with the biceps femoris partly having to compensate for the lack of endurance capacity of the semitendinosus, probably increase the hamstring injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. MRI-Based Regional Muscle Use during Hamstring Strengthening Exercises in Elite Soccer Players

    Science.gov (United States)

    Mendez-Villanueva, Alberto; Suarez-Arrones, Luis; Rodas, Gil; Fernandez-Gonzalo, Rodrigo; Tesch, Per; Linnehan, Richard; Kreider, Richard; Di Salvo, Valter

    2016-01-01

    The present study examined site-specific hamstring muscles use with functional magnetic resonance imaging (MRI) in elite soccer players during strength training. Thirty-six players were randomized into four groups, each performing either Nordic hamstring, flywheel leg-curl, Russian belt or the hip-extension conic-pulley exercise. The transverse relaxation time (T2) shift from pre- to post-MRI were calculated for the biceps femoris long (BFl) and short (BFs) heads, semitendinosus (ST) and semimembranosus (SM) muscles at proximal, middle and distal areas of the muscle length. T2 values increased substantially after flywheel leg-curl in all regions of the BFl (from 9±8 to 16±8%), BFs (41±6–71±11%), and ST (60±1–69±7%). Nordic hamstring induced a substantial T2 increase in all regions of the BFs (13±8–16±5%) and ST (15±7–17±5%). T2 values after the Russian belt deadlift substantially increased in all regions of the BFl (6±4–7±5%), ST (8±3–11±2%), SM (6±4–10±4%), and proximal and distal regions of BFs (6±6–8±5%). T2 values substantially increased after hip-extension conic-pulley only in proximal and middle regions of BFl (11±5–7±5%) and ST (7±3–12±4%). The relevance of such MRI-based inter- and intra-muscle use in designing more effective resistance training for improving hamstring function and preventing hamstring injuries in elite soccer players should be explored with more mechanistic studies. PMID:27583444

  17. The use of hamstring tendon graft for the anterior cruciate ligament reconstruction (benefi ts, problems and their solutions

    Directory of Open Access Journals (Sweden)

    V. V. Slastinin

    2017-01-01

    Full Text Available The search for optimal graft for anterior cruciate ligament reconstruction is going on. The donor site morbidity remains one of the major problems when using autografts. The article provides an overview of the advantages and disadvantages of using the hamstring tendon autografts for anterior cruciate ligament reconstruction, and the ways of solving the problems associated with using such types of grafts.

  18. Abnormal reflex activation of hamstring muscles in dogs with cranial cruciate ligament rupture.

    Science.gov (United States)

    Hayes, Graham M; Granger, Nicolas; Langley-Hobbs, Sorrel J; Jeffery, Nick D

    2013-06-01

    The mechanisms underlying cranial cruciate ligament rupture (CCLR) in dogs are poorly understood. In this study hamstring muscle reflexes in response to cranial tibial translation were analysed to determine whether these active stabilisers of the stifle joint are differently activated in dogs with CCLR compared to control dogs. In a prospective clinical study reflex muscle activity from the lateral and medial hamstring muscles (biceps femoris and semimembranosus) was recorded using surface electrodes in control dogs (n=21) and dogs with CCLR (n=22). These electromyographic recordings were analysed using an algorithm previously validated in humans. The hamstring reflex was reliably and reproducibly recorded in normal dogs. Both a short latency response (SLR, 17.6±2.1ms) and a medium latency response (MLR, 37.7±2.7ms) could be identified. In dogs with unilateral CCLR, the SLR and MLR were not significantly different between the affected and the unaffected limbs, but the MLR latency of both affected and unaffected limbs in CCLR dogs were significantly prolonged compared to controls. In conclusion, the hamstring reflex can be recorded in dogs and the MLR is prolonged in dogs with CCLR. Since both affected and unaffected limbs exhibit prolonged MLR, it is possible that abnormal hamstring reflex activation is a mechanism by which progressive CCL damage may occur. The methodology allows for further investigation of the relationship between neuromuscular imbalance and CCLR or limitations in functional recovery following surgical intervention. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Tissue-engineering strategies for the tendon/ligament-to-bone insertion.

    Science.gov (United States)

    Smith, Lester; Xia, Younan; Galatz, Leesa M; Genin, Guy M; Thomopoulos, Stavros

    2012-01-01

    Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require reattachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of reinjury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations.

  20. Flexor Tendon Injuries

    Science.gov (United States)

    ... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is ... Hand Therapist? Media Find a Hand Surgeon Home Anatomy ... fields From * To * DESCRIPTION The muscles that bend (flex) the fingers are called flexor ...

  1. Analysis of the Hamstring Muscle Activation During two Injury Prevention Exercises

    Science.gov (United States)

    Monajati, Alireza; Larumbe-Zabala, Eneko; Goss-Sampson, Mark

    2017-01-01

    Abstract The aim of this study was to perform an electromyographic and kinetic comparison of two commonly used hamstring eccentric strengthening exercises: Nordic Curl and Ball Leg Curl. After determining the maximum isometric voluntary contraction of the knee flexors, ten female athletes performed 3 repetitions of both the Nordic Curl and Ball Leg Curl, while knee angular displacement and electromyografic activity of the biceps femoris and semitendinosus were monitored. No significant differences were found between biceps femoris and semitendinosus activation in both the Nordic Curl and Ball Leg Curl. However, comparisons between exercises revealed higher activation of both the biceps femoris (74.8 ± 20 vs 50.3 ± 25.7%, p = 0.03 d = 0.53) and semitendinosus (78.3 ± 27.5 vs 44.3 ± 26.6%, p = 0.012, d = 0.63) at the closest knee angles in the Nordic Curl vs Ball Leg Curl, respectively. Hamstring muscles activation during the Nordic Curl increased, remained high (>70%) between 60 to 40° of the knee angle and then decreased to 27% of the maximal isometric voluntary contraction at the end of movement. Overall, the biceps femoris and semitendinosus showed similar patterns of activation. In conclusion, even though the hamstring muscle activation at open knee positions was similar between exercises, the Nordic Curl elicited a higher hamstring activity compared to the Ball Leg Curl. PMID:29339983

  2. Muscle injury is the principal injury type and hamstring muscle injury is the first injury diagnosis during top-level international athletics championships between 2007 and 2015.

    Science.gov (United States)

    Edouard, Pascal; Branco, Pedro; Alonso, Juan-Manuel

    2016-05-01

    During top-level international athletics championships, muscle injuries are frequent. To analyse the incidence and characteristics of muscle injuries and hamstring muscle injuries (hamstring injuries) occurring during top-level international athletics championships. During 16 international championships held between 2007 and 2015, national medical team and local organising committee physicians reported daily all injuries on a standardised injury report form. Only muscle injuries (muscle tears and muscle cramps) and hamstring injuries have been analysed. 40.9% of all recorded injuries (n=720) were muscle injuries, with 57.5% of them resulting in time loss. The overall incidence of muscle injuries was higher in male athletes than female athletes (51.9±6.0 vs 30.3±5.0 injuries per 1000 registered athletes, respectively; RR=1.71; 95% CI 1.45 to 2.01). Muscle injuries mainly affected the thigh (52.9%) and lower leg (20.1%), and were mostly caused by overuse with sudden onset (38.2%) and non-contact trauma (24.6%). Muscle injury risk varied according to the event groups. Hamstring injuries represented 17.1% of all injuries, with a higher risk in male compared to female athletes (22.4±3.4 vs 11.5±2.6 injuries per 1000 registered athletes, respectively; RR=1.94; 95% CI 1.42 to 2.66). During international athletics championships, muscle injury is the principal type of injury, and among those, the hamstring is the most commonly affected, with a two times higher risk in male than female athletes. Athletes in explosive power events, male athletes and older male athletes, in specific were more at risk of muscle injuries and hamstring injuries. Injury prevention strategies should be sex-specific. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Hamstring Muscle Fatigue and Central Motor Output during a Simulated Soccer Match

    Science.gov (United States)

    Marshall, Paul W. M.; Lovell, Ric; Jeppesen, Gitte K.; Andersen, Kristoffer; Siegler, Jason C.

    2014-01-01

    Purpose To examine changes in hamstring muscle fatigue and central motor output during a 90-minute simulated soccer match, and the concomitant changes in hamstring maximal torque and rate of torque development. Method Eight amateur male soccer players performed a 90-minute simulated soccer match, with measures performed at the start of and every 15-minutes during each half. Maximal torque (Nm) and rate of torque development (RTD; Nm.s–1) were calculated from maximal isometric knee flexor contractions performed at 10° of flexion. Hamstring peripheral fatigue was assessed from changes in the size and shape of the resting twitch (RT). Hamstring central motor output was quantified from voluntary activation (%) and normalized biceps femoris (BF) and medial hamstrings (MH) electromyographic amplitudes (EMG/M). Results Maximal torque was reduced at 45-minutes by 7.6±9.4% (phamstring peripheral fatigue. Conclusion Centrally mediated reductions in maximal torque and rate of torque development provide insight into factors that may explain hamstring injury risk during soccer. Of particular interest were early reductions during the first-half of hamstring rate of torque development, and the decline in maximal EMG/M of biceps femoris in the latter stages of the half. These are important findings that may help explain why the hamstrings are particularly vulnerable to strain injury during soccer. PMID:25047547

  4. Isokinetic evaluation of internal/external tibial rotation strength after the use of hamstring tendons for anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Armour, Tanya; Forwell, Lorie; Litchfield, Robert; Kirkley, Alexandra; Amendola, Ned; Fowler, Peter J

    2004-01-01

    Evaluation of the knee after an anterior cruciate ligament reconstruction with the use of the semitendinosus and gracilis (hamstring) autografts has primarily focused on flexion and extension strength. The semitendinosus and gracilis muscles contribute to internal tibial rotation, and it has been suggested that harvest of these tendons for the purpose of an anterior cruciate ligament reconstruction contributes to internal tibial rotation weakness. Internal tibial rotation strength may be affected by the semitendinosus and gracilis harvest after anterior cruciate ligament reconstruction. Prospective evaluation of internal and external tibial rotation strength. Inclusion criteria for subjects (N = 30): unilateral anterior cruciate ligament reconstruction at least 2 years previously, a stable anterior cruciate ligament (problems after initial knee reconstruction, a normal contralateral knee, and the ability to comply with the testing protocol. In an attempt to minimize unwanted subtalar joint motion, subjects were immobilized using an ankle brace and tested at angular velocities of 60 degrees /s, 120 degrees /s, and 180 degrees /s at a knee flexion angle of 90 degrees . The mean peak torque measurements for internal rotation strength of the operative limb (60 degrees /s, 17.4 +/- 4.5 ft-lb; 120 degrees /s, 13.9 +/- 3.3 ft-lb; 180 degrees /s, 11.6 +/- 3.0 ft-lb) were statistically different compared to the nonoperated limb (60 degrees /s, 20.5 +/- 4.7 ft-lb; 120 degrees /s, 15.9 +/- 3.8 ft-lb; 180 degrees /s, 13.4 +/- 3.8 ft-lb) at 60 degrees /s (P = .012), 120 degrees /s (P = .036), and 180 degrees /s (P = .045). The nonoperative limb demonstrated greater strength at all speeds. The mean torque measurements for external rotation were statistically similar when compared to the nonoperated limb at all angular velocities. We have shown through our study that patients who undergo surgical intervention to repair a torn anterior cruciate ligament with the use of autogenous

  5. TGIF1 Gene Silencing in Tendon-Derived Stem Cells Improves the Tendon-to-Bone Insertion Site Regeneration

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    Liyang Chen

    2015-11-01

    Full Text Available Background/Aims: The slow healing process of tendon-to-bone junctions can be accelerated via implanted tendon-derived stem cells (TDSCs with silenced transforming growth interacting factor 1 (TGIF1 gene. Tendon-to-bone insertion site is the special form of connective tissues derivatives of common connective progenitors, where TGF-β plays bidirectional effects (chondrogenic or fibrogenic through different signaling pathways at different stages. A recent study revealed that TGF-β directly induces the chondrogenic gene Sox9. However, TGIF1 represses the expression of the cartilage master Sox9 gene and changes its expression rate against the fibrogenesis gene Scleraxis (Scx. Methods: TGIF1 siRNA was transduced or TGIF1 was over-expressed in tendon-derived stem cells. Following suprapinatus tendon repair, rats were either treated with transduced TDSCs or nontransduced TDSCs. Histologic examination and Western blot were performed in both groups. Results: In this study, the silencing of TGIF1 significantly upregulated the chondrogenic genes and markers. Similarly, TGIF1 inhibited TDSC differentiation into cartilage via interactions with TGF-β-activated Smad2 and suppressed the phosphorylation of Smad2. The area of fibrocartilage at the tendon-bone interface was significantly increased in the TGIF1 (- group compared with the control and TGIF1-overexpressing groups in the early stages of the animal model. The interface between the tendon and bone showed a increase of new bone and fibrocartilage in the TGIF1 (- group at 4 weeks. Fibrovascular scar tissue was observed in the TGIF1-overexpressing group and the fibrin glue only group. Low levels of fibrocartilage and fibrovascular scar tissue were found in the TDSCs group. Conclusion: Collectively, this study shows that the tendon-derived stem cell modified with TGIF1 gene silencing has promising effects on tendon-to-bone healing which can be further explored as a therapeutic tool in regenerative medicine.

  6. Sport stretching : Effect on passive muscle stiffness of short hamstrings

    NARCIS (Netherlands)

    Halbertsma, JPK; vanBolhuis, AI; Goeken, LNH

    Objective: To evaluate the effects of one 10-minute stretch on muscle stiffness in subjects with short hamstrings. Design: Randomized control trial. Setting: Laboratory for human movement sciences in the department of rehabilitation of a university hospital. Subjects: Sixteen students from the

  7. Is application of Kinesio tape to treat hyperlordosis more effective on abdominal muscles or hamstrings?

    Directory of Open Access Journals (Sweden)

    Sara Abolahrari Shirazi

    2018-01-01

    Full Text Available Background: Hyperlordosis is defined as an abnormal increase in the lumbar arch of >40°. This study compared two taping techniques include abdominal muscles and hamstrings taping for the treatment of lumbar hyperlordosis. Materials and Methods: The randomized clinical trial was performed in Shiraz, Iran, during June and September 2014. Thirty women aged 20–45 years old with at least 40° lumbar lordosis participated. The women were randomized into two groups (n = 15. Abdominal muscles taping was performed for the first group, whereas the other group underwent hamstrings taping with 30% tension. Lumbar lordosis was measured before, immediately after, and 24 h after taping. The two-way repeated measures analysis of variance was used to compare the two groups for lumbar lordosis angle. Results: No significant differences were detected between the lumbar lordosis angles before and immediately after taping in the two groups (P > 0.05. However, a significant reduction was observed in lordosis angle in the abdominal group and the hamstring group 24 h after taping relative to before intervention (P < 0.01. Conclusion: Taping of the abdominal and hamstring muscles was not effective immediately, whereas it decreased lordosis after 24 h.

  8. Biomechanical properties of patellar and hamstring graft tibial fixation techniques in anterior cruciate ligament reconstruction: experimental study with roentgen stereometric analysis.

    Science.gov (United States)

    Adam, Frank; Pape, Dietrich; Schiel, Karin; Steimer, Oliver; Kohn, Dieter; Rupp, Stefan

    2004-01-01

    Reliable fixation of the soft hamstring grafts in ACL reconstruction has been reported as problematic. The biomechanical properties of patellar tendon (PT) grafts fixed with biodegradable screws (PTBS) are superior compared to quadrupled hamstring grafts fixed with BioScrew (HBS) or Suture-Disc fixation (HSD). Controlled laboratory study with roentgen stereometric analysis (RSA). Ten porcine specimens were prepared for each group. In the PT group, the bone plugs were fixed with a 7 x 25 mm BioScrew. In the hamstring group, four-stranded tendon grafts were anchored within a tibial tunnel of 8 mm diameter either with a 7 x 25 mm BioScrew or eight polyester sutures knotted over a Suture-Disc. The grafts were loaded stepwise, and micromotion of the graft inside the tibial tunnel was measured with RSA. Hamstring grafts failed at lower loads (HBS: 536 N, HSD 445 N) than the PTBS grafts (658 N). Stiffness in the PTBS group was much greater compared to the hamstring groups (3500 N/mm versus HBS = 517 N/mm and HSD = 111 N/mm). Irreversible graft motion after graft loading with 200 N was measured at 0.03 mm (PTBS), 0.38mm (HBS), and 1.85mm (HSD). Elasticity for the HSD fixation was measured at 0.67 mm at 100 N and 1.32 mm at 200 N load. Hamstring graft fixation with BioScrew and Suture-Disc displayed less stiffness and early graft motion compared to PTBS fixation. Screw fixation of tendon grafts is superior to Suture-Disc fixation with linkage material since it offers greater stiffness and less graft motion inside the tibial tunnel. Our results revealed graft motion for hamstring fixation with screw or linkage material at loads that occur during rehabilitation. This, in turn, may lead to graft laxity.

  9. Acute hamstring injury in football players: Association between anatomical location and extent of injury-A large single-center MRI report.

    Science.gov (United States)

    Crema, Michel D; Guermazi, Ali; Tol, Johannes L; Niu, Jingbo; Hamilton, Bruce; Roemer, Frank W

    2016-04-01

    To describe in detail the anatomic distribution of acute hamstring injuries in football players, and to assess the relationship between location and extent of edema and tears, all based on findings from MRI. Retrospective observational study. We included 275 consecutive male football players who had sustained acute hamstring injuries and had positive findings on MRI. For each subject, lesions were recorded at specific locations of the hamstring muscles, which were divided into proximal or distal: free tendon, myotendinous junction, muscle belly, and myofascial junction locations. For each lesion, we assessed the largest cross-sectional area of edema and/or tears. We calculated the prevalence of injuries by location. The relationships between locations and extent of edema and tears were assessed using a one-sample t-test, with significance set at pinjuries were most common in the myotendinous junction and in proximal locations. The proximal myotendinous junction was associated with a greater extent of edema in the LHBF and semitendinosus (ST) muscles (phamstring muscle injury. Distal locations (ST muscle), however, seem to be more commonly associated with larger tears. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  10. The relationship between previous hamstring injury and the concentric isokinetic knee muscle strength of irish gaelic footballers

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    O'Ceallaigh Brian

    2008-03-01

    Full Text Available Abstract Background Hamstring injury is one of the most common injuries affecting gaelic footballers, similar to other field sports. Research in other sports on whether residual hamstring weakness is present after hamstring injury is inconsistent, and no study has examined this factor in irish gaelic footballers. The aim of this study was to examine whether significant knee muscle weakness is present in male Irish gaelic footballers who have returned to full activity after hamstring injury. Methods The concentric isokinetic knee flexion and extension strength of 44 members of a university gaelic football team was assessed at 60, 180 and 300 degrees per second using a Contrex dynamometer. Results Fifteen players (34% reported a history of hamstring strain, with 68% of injuries affecting the dominant (kicking limb. The hamstrings were significantly stronger (p 0.05 using this comparison. The previously unilaterally injured hamstrings were significantly weaker (p Conclusion Hamstring muscle weakness was observed in male Irish gaelic footballers with a history of hamstring injury. This weakness is most evident when comparisons are made to multiple control populations, both within and between subjects. The increased strength of the dominant limb should be considered as a potential confounding variable in future trials. The study design does not allow interpretation of whether these changes in strength were present before or after injury.

  11. COMPARISON OF CONCENTRIC AND ECCENTRIC HAMSTRING STRENGTH TRAINING IN IMPROVING MUSCLE STRENGTH AND POWER AMONG FUTSAL PLAYERS A RANDOMIZED CONTROLLED TRIAL

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    Arunkumar Nedunchezhiyan

    2016-12-01

    Full Text Available Background: Hamstring injury is a common problem in many sports, especially those involving acceleration and maximal sprints. Hamstring strains are both common and painful. During sprinting the hip flexor and knee extensor torques are frequently produced and is opposed by the hamstring muscles, hence there are numerous studies done on the muscle strength training to prevent the hamstring strain injury as it is statistically stated as the highest rate involved injury in the contact sport. This study has been focused to evaluate the effectiveness of concentric and eccentric exercises in improving hamstring muscle strength and power among futsal players. Method: Thirty recreational futsal players were recruited for the study and were randomly divided into two groups. Each group received either hamstring curl exercise (concentric or Nordic hamstring exercise (eccentric twice a week for 4 weeks. The manual muscle test (MMT and 40-yard dash test was used to evaluate the muscle strength and power respectively by comparing the pretest and posttest values for both groups. Results: Wilcoxon signed rank test showed that there is no statistically significant difference between pre and post test values of MMT (Concentric (right side, z=.317; left side, z=.157, Eccentric (right side, z=.157; left side, z=.317 in both groups. Based on paired 't' test there is a significant difference between the pre and post test on improving muscle power [Concentric group, P=.020; Eccentric Group, P=.000]. Mann–Whitney U test and unpaired 't' test showed that there is no significant difference between both groups of MMT (z=.775 and 40-yard dash test (P=.707 respectively. Conclusion: The concentric strength training and eccentric strength training have a similar effect in improving hamstring muscle power in futsal players.

  12. Expression of collagen and related growth factors in rat tendon and skeletal muscle in response to specific contraction types.

    Science.gov (United States)

    Heinemeier, K M; Olesen, J L; Haddad, F; Langberg, H; Kjaer, M; Baldwin, K M; Schjerling, P

    2007-08-01

    Acute exercise induces collagen synthesis in both tendon and muscle, indicating an adaptive response in the connective tissue of the muscle-tendon unit. However, the mechanisms of this adaptation, potentially involving collagen-inducing growth factors (such as transforming growth factor-beta-1 (TGF-beta-1)), as well as enzymes related to collagen processing, are not clear. Furthermore, possible differential effects of specific contraction types on collagen regulation have not been investigated. Female Sprague-Dawley rats were subjected to 4 days of concentric, eccentric or isometric training (n = 7-9 per group) of the medial gastrocnemius, by stimulation of the sciatic nerve. RNA was extracted from medial gastrocnemius and Achilles tendon tissue 24 h after the last training bout, and mRNA levels for collagens I and III, TGF-beta-1, connective tissue growth factor (CTGF), lysyl oxidase (LOX), metalloproteinases (MMP-2 and -9) and their inhibitors (TIMP-1 and 2) were measured by Northern blotting and/or real-time PCR. In tendon, expression of TGF-beta-1 and collagens I and III (but not CTGF) increased in response to all types of training. Similarly, enzymes/factors involved in collagen processing were induced in tendon, especially LOX (up to 37-fold), which could indicate a loading-induced increase in cross-linking of tendon collagen. In skeletal muscle, a similar regulation of gene expression was observed, but in contrast to the tendon response, the effect of eccentric training was significantly greater than the effect of concentric training on the expression of several transcripts. In conclusion, the study supports an involvement of TGF-beta-1 in loading-induced collagen synthesis in the muscle-tendon unit and importantly, it indicates that muscle tissue is more sensitive than tendon to the specific mechanical stimulus.

  13. Rotator cuff repair with a tendon-fibrocartilage-bone composite bridging patch.

    Science.gov (United States)

    Ji, Xiaoxi; Chen, Qingshan; Thoreson, Andrew R; Qu, Jin; An, Kai-Nan; Amadio, Peter C; Steinmann, Scott P; Zhao, Chunfeng

    2015-11-01

    To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model. Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/s. The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; Pfibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch-greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. METODE ACTIVE ISOLATED STRETCHING (AIS DAN METODE HOLD RELAX STRETCHING (HRS SAMA EFEKTIF DALAM MENINGKATKAN FLEKSIBILITAS OTOT HAMSTRING PADA MAHASISWA AKADEMI FISIOTERAPI WIDYA HUSADA SEMARANG YANG MENGALAMI HAMSTRING MUSCLE TIGHTNESS (HMTs

    Directory of Open Access Journals (Sweden)

    Akhmad alfajri

    2015-08-01

    Full Text Available Students with Hamstring Muscle Tightness (HMTs will be at risk of Anterior Crusiatum Ligament (ACL, Low Back Pain (LBP and also Plantar Faciitis. One of the efforts to reduce tightness and improve hamstring muscle flexibility is stretching. Active Isolated Stretching (AIS and Hold Relax Stretching (HRS are the methods of influential stretching to improve muscle flexibility. The goal of the research is to prove that AIS method is equally effective with the HRS method to improve hamstring muscle flexibility to the HMTs patients. The research method was true experimental with pre and post test group design. The research was conducted for 3 weeks and the samples are 23 students in range of 18-25 years old students of physical therapy in Physical Therapy Academy of Widya Husada Semarang which divided into 2 groups; AIS group (n= 12 and HRS group (n= 11. The research used Sit and Reach Test (SRT as the measurement instrument. The result of the research was the average result of AIS group used SRT before treatment was 1.75 cm, SB= 4.309 and after treatment was 10. 58 cm, SB = 8. 005 within p= 0.000 (p 0.05. Those explain that the improvement of hamstring muscle flexibility to the two groups does not show any significant difference. Conclusion from this study was active isolated stretching method and hold relax stretching method are equally effective to improving muscle flexibility of hamstring muscle tightness students of physical therapy in Physical Therapy Academy of Widya Husada Semarang.

  15. The effects of a 4-week static stretching programme on the individual muscles comprising the hamstrings.

    Science.gov (United States)

    Ichihashi, Noriaki; Umegaki, Hiroki; Ikezoe, Tome; Nakamura, Masatoshi; Nishishita, Satoru; Fujita, Kosuke; Umehara, Jun; Nakao, Sayaka; Ibuki, Satoko

    2016-12-01

    The aims of this study were to investigate the effects of a 4-week intervention of static stretching (SS) on muscle hardness of the semitendinosus (ST), semimembranosus (SM) and biceps femoris (BF) muscles. Shear elastic modulus was measured by using ultrasound shear wave elastography as the index of muscle hardness. Thirty healthy men (age 22.7 ± 2.2 years) volunteered for this study and were randomly assigned to the SS intervention group (n = 15) or the control group (n = 15). Participants in the SS intervention group received a 4-week stretch intervention for the hamstrings of their dominant leg. Shear elastic moduli of the hamstrings were measured at initial evaluation and after 4 weeks in both groups at a determined angle. In all muscles, the shear elastic modulus decreased significantly after SS intervention. The percentage change in the shear elastic modulus from the value at initial evaluation to after 4 weeks intervention was greatest in the SM. These results suggest that SS intervention has chronic effects on reducing hardness of the hamstring muscle components, especially the SM muscle.

  16. Nordic hamstring exercise training alters knee joint kinematics and hamstring activation patterns in young men.

    Science.gov (United States)

    Delahunt, Eamonn; McGroarty, Mark; De Vito, Giuseppe; Ditroilo, Massimiliano

    2016-04-01

    To investigate the kinematic and muscle activation adaptations during performance of the Nordic hamstring exercise (NHE) to a 6-week eccentric hamstring training programme using the NHE as the sole mode of exercise. Twenty-nine healthy males were randomly allocated to a control (CG) or intervention (IG) group. The IG participated in a 6-week eccentric hamstring exercise programme using the NHE. The findings of the present study were that a 6-week eccentric hamstring training programme improved eccentric hamstring muscle strength (202.4 vs. 177.4 nm, p = 0.0002, Cohen's d = 0.97) and optimized kinematic (longer control of the forward fall component of the NHE, 68.1° vs. 73.7°, p = 0.022, Cohen's d = 0.90) and neuromuscular parameters (increased electromyographic activity of the hamstrings, 83.2 vs. 56.6 % and 92.0 vs. 54.2 %, p 1.25) associated with NHE performance. This study provides some insight into potential mechanisms by which an eccentric hamstring exercise programme utilizing the NHE as the mode of exercise may result in an improvement in hamstring muscle control during eccentric contractions.

  17. Tendon material properties vary and are interdependent among turkey hindlimb muscles.

    Science.gov (United States)

    Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P; Roberts, Thomas J

    2012-10-15

    The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress-strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65±0.83 to 94.02±0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r(2)=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity.

  18. Muscle-tendon-related abnormalities detected by ultrasonography are common in symptomatic hip dysplasia

    DEFF Research Database (Denmark)

    Jacobsen, Julie Sandell; Bolvig, Lars; Hölmich, Per

    2018-01-01

    INTRODUCTION: Hip dysplasia is characterized by reduced acetabular coverage of the femoral head leading to an increased mechanical load on the hip joint and the acting hip muscles. Potentially, the muscles and tendons functioning close to the hip joint may present with overuse......-related ultrasonography findings. The primary aim was to report the prevalence of muscle-tendon-related abnormalities detected by ultrasonography in 100 patients with symptomatic hip dysplasia. The secondary aim was to investigate correlations between muscle-tendon-related abnormalities detected by ultrasonography......-tendon-related abnormalities detected by ultrasonography in the hip and groin region are common in patients with symptomatic hip dysplasia, and the ultrasonography findings of the iliopsoas and gluteus medius/minimus tendons are weakly to moderately correlated to pain related to muscles and tendons in these structures. Both...

  19. Effects of Inclined Treadmill Walking on Pelvic Anterior Tilt Angle, Hamstring Muscle Length, and Trunk Muscle Endurance of Seated Workers with Flat-back Syndrome

    OpenAIRE

    Kim, Min-hee; Yoo, Won-gyu

    2014-01-01

    [Purpose] This study investigated the effects of inclined treadmill walking on pelvic anterior tilt angle, hamstring muscle length, and back muscle endurance of seated workers with flat-back syndrome. [Subjects] Eight seated workers with flat-back syndrome who complained of low-back pain in the L3–5 region participated in this study. [Methods] The subjects performed a walking exercise on a 30° inclined treadmill. We measured the pelvic anterior tilt angle, hamstring muscle length, and back mu...

  20. The effects of stretching on the flexibility, muscle performance and functionality of institutionalized older women

    Directory of Open Access Journals (Sweden)

    D. Gallon

    2011-03-01

    Full Text Available Stretching has been widely used to increase the range of motion. We assessed the effects of a stretching program on muscle-tendon length, flexibility, torque, and activities of daily living of institutionalized older women. Inclusion/exclusion criteria were according to Mini-Mental State Examination (MMSE (>13, Barthel Index (>13 and Lysholm Scoring Scale (>84. Seventeen 67 ± 9 year-old elderly women from a nursing home were divided into 2 groups at random: the control group (CG, N = 9 participated in enjoyable cultural activities; the stretching group (SG, N = 8 performed active stretching of hamstrings, 4 bouts of 1 min each. Both groups were supervised three times per week over a period of 8 weeks. Peak torque was assessed by an isokinetic method. Both groups were evaluated by a photogrammetric method to assess muscle-tendon length of uni- and biarticular hip flexors and hamstring flexibility. All measurements were analyzed before and after 8 weeks by two-way ANOVA with the level of significance set at 5%. Hamstring flexibility increased by 30% in the SG group compared to pre-training (76.5 ± 13.0° vs 59.5 ± 9.0°, P = 0.0002 and by 9.2% compared to the CG group (76.5 ± 13.0° vs 64.0 ± 12.0°, P = 0.0018. Muscle-tendon lengths of hip biarticular flexor muscles (124 ± 6.8° vs 118.3 ± 7.6°, 5.0 ± 7.0%, P = 0.031 and eccentric knee extensor peak torque were decreased in the CG group compared to pre-test values (-49.4 ± 16.8 vs -60.5 ± 18.9 Nm, -15.7 ± 20%, P = 0.048. The stretching program was sufficient to increase hamstring flexibility and a lack of stretching can cause reduction of muscle performance.

  1. Hamstring muscle length and pelvic tilt range among individuals with and without low back pain.

    Science.gov (United States)

    Fasuyi, Francis Oluwafunsho; Fabunmi, Ayodele A; Adegoke, Babatunde O A

    2017-04-01

    Hamstring tightness has been documented not to be related to the pelvic tilt position during static standing posture, but there is limited data on the relationship between hamstring muscle length (HML) and pelvic tilt range (PTR) during the dynamic movement of forward bending. This ex-post facto study was designed to compare each of HML and PTR in individuals with low back pain (LBP) and counterparts without LBP, and the relationship between HML and PTR in individuals with and without LBP. The study involved 30 purposively recruited individuals with LBP and 30 height and weight-matched individuals without LBP. Participants' PTR and HML were assessed using digital inclinometer and active knee extension test respectively. Data were analyzed using t-test and Pearson Correlation (r) at α = 0.05. Participants without LBP had significantly longer (p = 0.01) HML than those with LBP but the PTR of both groups were not significantly different. HML and PTR had indirect but not significant correlations in participants with and without LBP. Hamstring muscle length is significantly reduced in individuals with LBP but it has no significant correlation with pelvic tilt range. Pelvic tilt range reduces as hamstring muscle length increases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Bone marrow-derived mesenchymal stem cells influence early tendon-healing in a rabbit achilles tendon model.

    Science.gov (United States)

    Chong, Alphonsus K S; Ang, Abel D; Goh, James C H; Hui, James H P; Lim, Aymeric Y T; Lee, Eng Hin; Lim, Beng Hai

    2007-01-01

    A repaired tendon needs to be protected for weeks until it has accrued enough strength to handle physiological loads. Tissue-engineering techniques have shown promise in the treatment of tendon and ligament defects. The present study tested the hypothesis that bone marrow-derived mesenchymal stem cells can accelerate tendon-healing after primary repair of a tendon injury in a rabbit model. Fifty-seven New Zealand White rabbits were used as the experimental animals, and seven others were used as the source of bone marrow-derived mesenchymal stem cells. The injury model was a sharp complete transection through the midsubstance of the Achilles tendon. The transected tendon was immediately repaired with use of a modified Kessler suture and a running epitendinous suture. Both limbs were used, and each side was randomized to receive either bone marrow-derived mesenchymal stem cells in a fibrin carrier or fibrin carrier alone (control). Postoperatively, the rabbits were not immobilized. Specimens were harvested at one, three, six, and twelve weeks for analysis, which included evaluation of gross morphology (sixty-two specimens), cell tracing (twelve specimens), histological assessment (forty specimens), immunohistochemistry studies (thirty specimens), morphometric analysis (forty specimens), and mechanical testing (sixty-two specimens). There were no differences between the two groups with regard to the gross morphology of the tendons. The fibrin had degraded by three weeks. Cell tracing showed that labeled bone marrow-derived mesenchymal stem cells remained viable and present in the intratendinous region for at least six weeks, becoming more diffuse at later time-periods. At three weeks, collagen fibers appeared more organized and there were better morphometric nuclear parameters in the treatment group (p tendon repair can improve histological and biomechanical parameters in the early stages of tendon-healing.

  3. Muscle-tendon-related pain in 100 patients with hip dysplasia: prevalence and associations with self-reported hip disability and muscle strength

    DEFF Research Database (Denmark)

    Jacobsen, Julie Sandell; Hølmich, Per; Thorborg, Kristian

    2018-01-01

    The primary aim was to identify muscle-tendon-related pain in 100 patients with hip dysplasia. The secondary aim was to test whether muscle-tendon-related pain is associated with self-reported hip disability and muscle strength in patient with hip dysplasia. One hundred patients (17 men......-tendon-related pain and hip extension a significant inverse linear association between muscle-tendon-related pain and muscle strength was found ranging from -0.11 to - 0.12 Nm/kg in the adjusted analysis (P hip dysplasia with a high prevalence......) with a mean age of 29 years (SD 9) were included. Clinical entity approach was carried out to identify muscle-tendon-related pain. Associations between muscle-tendon-related pain and self-reported hip disability and muscle strength were tested with multiple regression analysis, including adjustments for age...

  4. Repeated freeze-thaw cycles reduce the survival rate of osteocytes in bone-tendon constructs without affecting the mechanical properties of tendons.

    Science.gov (United States)

    Suto, Kaori; Urabe, Ken; Naruse, Kouji; Uchida, Kentaro; Matsuura, Terumasa; Mikuni-Takagaki, Yuko; Suto, Mitsutoshi; Nemoto, Noriko; Kamiya, Kentaro; Itoman, Moritoshi

    2012-03-01

    Frozen bone-patellar tendon bone allografts are useful in anterior cruciate ligament reconstruction as the freezing procedure kills tissue cells, thereby reducing immunogenicity of the grafts. However, a small portion of cells in human femoral heads treated by standard bone-bank freezing procedures survive, thus limiting the effectiveness of allografts. Here, we characterized the survival rates and mechanisms of cells isolated from rat bones and tendons that were subjected to freeze-thaw treatments, and evaluated the influence of these treatments on the mechanical properties of tendons. After a single freeze-thaw cycle, most cells isolated from frozen bone appeared morphologically as osteocytes and expressed both osteoblast- and osteocyte-related genes. Transmission electron microscopic observation of frozen cells using freeze-substitution revealed that a small number of osteocytes maintained large nuclei with intact double membranes, indicating that these osteocytes in bone matrix were resistant to ice crystal formation. We found that tendon cells were completely killed by a single freeze-thaw cycle, whereas bone cells exhibited a relatively high survival rate, although survival was significantly reduced after three freeze-thaw cycles. In patella tendons, the ultimate stress, Young's modulus, and strain at failure showed no significant differences between untreated tendons and those subjected to five freeze-thaw cycles. In conclusion, we identified that cells surviving after freeze-thaw treatment of rat bones were predominantly osteocytes. We propose that repeated freeze-thaw cycles could be applied for processing bone-tendon constructs prior to grafting as the treatment did not affect the mechanical property of tendons and drastically reduced surviving osteocytes, thereby potentially decreasing allograft immunogenecity.

  5. Strength deficits identified with concentric action of the hip extensors and eccentric action of the hamstrings predispose to hamstring injury in elite sprinters.

    Science.gov (United States)

    Sugiura, Yusaku; Saito, Tomoyuki; Sakuraba, Keishoku; Sakuma, Kazuhiko; Suzuki, Eiichi

    2008-08-01

    Prospective cohort study. In this prospective cohort study of elite sprinters, muscle strength of the hip extensors, as well as of the knee extensors and flexors, was measured to determine a possible relationship between strength deficits and subsequent hamstring injury within 12 months of testing. The method used for testing muscle strength simulated the specific muscle action during late swing and early contact phases when sprinting. There have been no prospective studies in elite sprinters that examine the concentric and eccentric isokinetic strength of the hip extensors and the quadriceps and hamstring muscles in a manner that reflects their actions in late swing or early contact phases of sprinting. Consequently, the causal relationship between hip and thigh muscle strength and hamstring injury in elite sprinters may not be fully understood. Isokinetic testing was performed on 30 male elite sprinters to assess hip extensors, quadriceps, and hamstring muscle strength. The occurrence of hamstring injury among the subjects was determined during the year following the muscle strength measurements. The strength of the hip extensors, quadriceps, and hamstring muscles, as well as the hamstrings-quadriceps and hip extensors- quadriceps ratios were compared. Hamstring injury occurred in 6 subjects during the 1-year period. Isokinetic testing at a speed of 60 degrees /s revealed weakness of the injured limb with eccentric action of the hamstring muscles and during concentric action of the hip extensors. When performing a side-to-side comparison for the injured sprinters, the hamstring injury always occurred on the weaker side. Differences in the hamstrings-quadriceps and hip extensors-quadriceps strength ratios were also evident between uninjured and injured limbs, and this was attributable to deficits in hamstring strength. Hamstring injury in elite sprinters was associated with weakness during eccentric action of the hamstrings and weakness during concentric action of

  6. Effect of tendon vibration during wide-pulse neuromuscular electrical stimulation (NMES) on the decline and recovery of muscle force.

    Science.gov (United States)

    Bochkezanian, Vanesa; Newton, Robert U; Trajano, Gabriel S; Vieira, Amilton; Pulverenti, Timothy S; Blazevich, Anthony J

    2017-05-02

    Neuromuscular electrical stimulation (NMES) is commonly used to activate skeletal muscles and reverse muscle atrophy in clinical populations. Clinical recommendations for NMES suggest the use of short pulse widths (100-200 μs) and low-to-moderate pulse frequencies (30-50 Hz). However, this type of NMES causes rapid muscle fatigue due to the (non-physiological) high stimulation intensities and non-orderly recruitment of motor units. The use of both wide pulse widths (1000 μs) and tendon vibration might optimize motor unit activation through spinal reflex pathways and thus delay the onset of muscle fatigue, increasing muscle force and mass. Thus, the objective of this study was to examine the acute effects of patellar tendon vibration superimposed onto wide-pulse width (1000 μs) knee extensor electrical stimulation (NMES, 30 Hz) on peak muscle force, total impulse before "muscle fatigue", and the post-exercise recovery of muscle function. Tendon vibration (Vib), NMES (STIM) or NMES superimposed onto vibration (STIM + Vib) were applied in separate sessions to 16 healthy adults. Total torque-time integral (TTI), maximal voluntary contraction torque (MVIC) and indirect measures of muscle damage were tested before, immediately after, 1 h and 48 h after each stimulus. TTI increased (145.0 ± 127.7%) in STIM only for "positive responders" to the tendon vibration (8/16 subjects), but decreased in "negative responders" (-43.5 ± 25.7%). MVIC (-8.7%) and rectus femoris electromyography (RF EMG) (-16.7%) decreased after STIM (group effect) for at least 1 h, but not after STIM + Vib. No changes were detected in indirect markers of muscle damage in any condition. Tendon vibration superimposed onto wide-pulse width NMES increased TTI only in 8 of 16 subjects, but reduced voluntary force loss (fatigue) ubiquitously. Negative responders to tendon vibration may derive greater benefit from wide-pulse width NMES alone.

  7. Pectoralis Major Tear with Retracted Tendon: How to Fill the Gap? Reconstruction with Hamstring Autograft and Fixation with an Interference Screw

    Directory of Open Access Journals (Sweden)

    L. Baverel

    2017-01-01

    Full Text Available Rupture of the pectoralis major tendon is considered an uncommon injury and a significant number of ruptures are missed or diagnosed late, leading to a chronic tear. We report an open reconstruction technique and its outcomes in a case of chronic and retracted PM tear. At the last follow-up (12 months, the patient was pain-free, with a visual analogic scale at 0 all the time. He was very satisfied concerning the cosmetic and clinical results. The constant score was 93%, the SST value 95%, and the Quick DASH score 4.5. MRI performed one year postoperatively confirmed the continuity between PM tendon and graft, even if the aspect of the distal tendon seemed to be thinner than normal PM tendon. The excellent clinical outcomes at one-year follow-up suggest that PM tear with major tendon retraction can be reliably reconstructed with hamstring autograft, using a bioabsorbable screw to optimize the fixation device. This technique has proven its simplicity and efficiency to fill the gap.

  8. Achilles Tendon Rupture

    Science.gov (United States)

    ... is a strong fibrous cord that connects the muscles in the back of your calf to your heel bone. If you overstretch your Achilles tendon, it can tear (rupture) completely or just partially. If your Achilles ...

  9. Effect of quadriceps and hamstrings muscle cooling on standing balance in healthy young men.

    Science.gov (United States)

    Alghadir, A H; Anwer, S; Zafar, H; Al-Eisa, E S

    2017-09-01

    The present study compared the effect of quadriceps and hamstring muscle cooling on standing balance in healthy young men. Thirty healthy young men (18-30 years) participated in the study. The participants were randomly assigned to three groups (n=10 each): quadriceps cooling (QC), hamstring cooling (HC), or control group (no cooling). Participants in the QC and HC groups received 20 minutes of cooling using a cold pack (gel pack), placed on the anterior thigh (from the apex of the patella to the mid-thigh) and the posterior thigh (from the base of the popliteal fossa to the mid-thigh), respectively. Balance score including unilateral stance was measured at baseline and immediately after the application of the cold pack. No significant difference in the balance score was noted in any group after the application of the cold pack (p⟩0.05). Similarly, no significant differences in post-test balance score were noted among the three groups (p⟩0.05). Cooling of the quadriceps and hamstring muscles has no immediate effect on standing balance in healthy young men. However, longitudinal studies are warranted to investigate the long-term effects of cooling these muscles on standing balance.

  10. The adductor magnus ''mini-hamstring'': MRI appearance and potential pitfalls

    International Nuclear Information System (INIS)

    Broski, Stephen M.; Murthy, Naveen S.; Collins, Mark S.; Krych, Aaron J.; Obey, Mitchel R.

    2016-01-01

    To examine the anatomic MRI characteristics of the adductor magnus mini hamstring (AMMH) and explore its involvement in cases of hamstring avulsion. An IRB-approved retrospective review of patients undergoing ''hamstring protocol'' MRI between March 2009 and June 2014 was performed. Two musculoskeletal radiologists recorded multiple AMMH anatomic characteristics and involvement in cases of hamstring avulsion. Seventy-six AMMHs were analyzed in 66 patients [35 females and 31 males, mean age 49.3 ± 15.2 years (range 17-81)]. Eleven percent of AMMHs were poorly visualized, 51 % visualized, and 37 % well visualized. Seven percent demonstrated round, 73 % ovoid, and 21 % flat/lenticular tendon morphologies. Most (88 %) demonstrated typical origins. Average cross-sectional area (CSA) was 22.4 ± 10.6 mm 2 (range 6-56), diameter was 7.2 ± 2.5 mm (range 2.9-15), medial distance from the semimembranosus tendon was 7.5 ± 2.5 mm (range 3-14), and tendon length was 6.8 ± 3.3 cm (range 1.2-14.1). There was no gender difference in AMMH anatomic measurements or correlation between age and CSA or diameter. Of 17 complete hamstring avulsion cases, the AMMH was intact in 13, partially torn in 3, and completely torn in 1. The AMMH is a constant finding with variable anatomic characteristics. It is visualized or well visualized by MRI in 88 % of cases and is a sizable tendon located in close proximity to the semimembranosus tendon. Because it is uncommonly completely torn (6 %) in cases of complete hamstring avulsion, radiologists should be aware of its presence and appearance to avoid diagnostic confusion. (orig.)

  11. The adductor magnus ''mini-hamstring'': MRI appearance and potential pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Broski, Stephen M.; Murthy, Naveen S.; Collins, Mark S. [Department of Radiology, Mayo Clinic, Rochester, MN (United States); Krych, Aaron J. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN (United States); Obey, Mitchel R. [Mayo School of Graduate Medical Education, Rochester, MN (United States)

    2016-02-15

    To examine the anatomic MRI characteristics of the adductor magnus mini hamstring (AMMH) and explore its involvement in cases of hamstring avulsion. An IRB-approved retrospective review of patients undergoing ''hamstring protocol'' MRI between March 2009 and June 2014 was performed. Two musculoskeletal radiologists recorded multiple AMMH anatomic characteristics and involvement in cases of hamstring avulsion. Seventy-six AMMHs were analyzed in 66 patients [35 females and 31 males, mean age 49.3 ± 15.2 years (range 17-81)]. Eleven percent of AMMHs were poorly visualized, 51 % visualized, and 37 % well visualized. Seven percent demonstrated round, 73 % ovoid, and 21 % flat/lenticular tendon morphologies. Most (88 %) demonstrated typical origins. Average cross-sectional area (CSA) was 22.4 ± 10.6 mm{sup 2} (range 6-56), diameter was 7.2 ± 2.5 mm (range 2.9-15), medial distance from the semimembranosus tendon was 7.5 ± 2.5 mm (range 3-14), and tendon length was 6.8 ± 3.3 cm (range 1.2-14.1). There was no gender difference in AMMH anatomic measurements or correlation between age and CSA or diameter. Of 17 complete hamstring avulsion cases, the AMMH was intact in 13, partially torn in 3, and completely torn in 1. The AMMH is a constant finding with variable anatomic characteristics. It is visualized or well visualized by MRI in 88 % of cases and is a sizable tendon located in close proximity to the semimembranosus tendon. Because it is uncommonly completely torn (6 %) in cases of complete hamstring avulsion, radiologists should be aware of its presence and appearance to avoid diagnostic confusion. (orig.)

  12. Triceps brachii tendon: anatomic-MR imaging study in cadavers with histologic correlation

    International Nuclear Information System (INIS)

    Belentani, Clarissa; Pastore, Daniel; Wangwinyuvirat, Mani; Dirim, Berna; Trudell, Debra J.; Resnick, Donald; Haghighi, Parviz

    2009-01-01

    The purpose of this cadaveric study was to describe the normal MR anatomy of the triceps brachii tendon (TBT) insertion, to correlate the findings with those seen in anatomic sections and histopathologic analysis, and to review triceps tendon injuries. Twelve cadaveric elbows were used according to institution guidelines. T1-weighted spin-echo MR images were acquired in three planes. Findings on MR imaging were correlated with those derived from anatomic and histologic study. On MR images, the TBT had a bipartite appearance as it inserted on olecranon in all specimens. The insertion of the medial head was deeper than that of the long and lateral heads and was mainly muscular at its insertion, with a small amount of the tendon blending with the muscle distally, necessitating histologic analysis to determine if there was tendon blending with the muscle at the site of insertion and if the medial head inserted together with the common tendon or as a single unit. At histopathologic analysis, the three heads of the triceps tendon had a common insertion on the olecranon. The bipartite aspect of the tendon that was identified in the MR images was not seen by histologic study, indicating that there was a union of the medial and common tendons just before they inserted into bone. TBT has a bipartite appearance on MR images and inserts on olecranon as a single unit. (orig.)

  13. Triceps brachii tendon: anatomic-MR imaging study in cadavers with histologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Belentani, Clarissa [University of California, Department of Radiology, San Diego, CA (United States); Pastore, Daniel; Wangwinyuvirat, Mani; Dirim, Berna; Trudell, Debra J.; Resnick, Donald [University of California, Department of Radiology, San Diego, CA (United States); University of California, VA Medical Center, San Diego, CA (United States); Haghighi, Parviz [University of California, VA Medical Center, San Diego, CA (United States); University of California, Department of Histology, San Diego (United States)

    2009-02-15

    The purpose of this cadaveric study was to describe the normal MR anatomy of the triceps brachii tendon (TBT) insertion, to correlate the findings with those seen in anatomic sections and histopathologic analysis, and to review triceps tendon injuries. Twelve cadaveric elbows were used according to institution guidelines. T1-weighted spin-echo MR images were acquired in three planes. Findings on MR imaging were correlated with those derived from anatomic and histologic study. On MR images, the TBT had a bipartite appearance as it inserted on olecranon in all specimens. The insertion of the medial head was deeper than that of the long and lateral heads and was mainly muscular at its insertion, with a small amount of the tendon blending with the muscle distally, necessitating histologic analysis to determine if there was tendon blending with the muscle at the site of insertion and if the medial head inserted together with the common tendon or as a single unit. At histopathologic analysis, the three heads of the triceps tendon had a common insertion on the olecranon. The bipartite aspect of the tendon that was identified in the MR images was not seen by histologic study, indicating that there was a union of the medial and common tendons just before they inserted into bone. TBT has a bipartite appearance on MR images and inserts on olecranon as a single unit. (orig.)

  14. Extensibility of the hamstrings is best explained by mechanical components of muscle contraction, not behavioral measures in individuals with chronic low back pain.

    Science.gov (United States)

    Marshall, Paul W M; Mannion, Jamie; Murphy, Bernadette A

    2009-08-01

    To examine the relationship between hamstring extensibility by use of the instrumented straight leg raise; mechanical components of muscle contraction, including muscle recruitment, passive torque measures of tissue stiffness, and eccentric strength; and self-reported measures of pain and disability. Cross-sectional study. University laboratory. Twenty-one individuals with chronic nonspecific axial lower back pain and 15 healthy control subjects. Instrumented straight leg raise, concentric and eccentric hamstring strength, self-reported measures of pain, disability, fear avoidance, general health and well-being Objective measures included hamstring extensibility, hamstring muscle stiffness, absolute and relative concentric/eccentric strength, concentric/eccentric strength ratios. Self-reported measures included Oswestry disability index, visual analog pain scale, fear avoidance beliefs, and general health and well being. Patients with lower back pain had lower range of motion, greater changes in muscle stiffness, and impaired concentric-to-eccentric strength levels. Stepwise regression identified measures of stiffness as significantly predicting hamstring extensibility (adjusted r(2) = 0.58, F = 23.76, P hamstrings also was associated with greater hamstring extensibility. Decreased extensibility of the hamstrings was associated with increased passive stiffness during the common range of motion (20 to 50 degrees ). Impaired stretch tolerance is associated with actual mechanical restriction, not behavioral measures indicating increased pain or fear-avoidant behavior. With no relationship to actual disability and contradictory findings in the literature for the relationship of the hamstrings to the mechanics of the low back, it is unclear whether decreased hamstring extensibility should be targeted in rehabilitation programs for axial lower back pain.

  15. Increased muscle belly and tendon stiffness in patients with Parkinson's disease, as measured by myotonometry.

    Science.gov (United States)

    Marusiak, Jarosław; Jaskólska, Anna; Budrewicz, Sławomir; Koszewicz, Magdalena; Jaskólski, Artur

    2011-09-01

    Based on Davis's law, greater tonus of the muscle belly in individuals with Parkinson's disease can create greater tension in the tendon, leading to structural adjustment and an increase in tendon stiffness. Our study aimed to separately assess passive stiffness in the muscle belly and tendon in medicated patients with Parkinson's disease, using myotonometry. We tested 12 patients with Parkinson's disease and 12 healthy matched controls. Passive stiffness of muscle belly and tendon was estimated by myotonometry, electromyography, and mechanomyography in relaxed biceps and triceps brachii muscles. Compared with controls, patients with Parkinson's disease had higher stiffness in the muscle belly and tendon of the biceps brachii and in the tendon of the triceps brachii. In patients with Parkinson's disease, there was a positive correlation between muscle belly stiffness and parkinsonian rigidity in the biceps brachii. Patients with Parkinson's disease have higher passive stiffness of the muscle belly and tendon than healthy matched controls. Copyright © 2011 Movement Disorder Society.

  16. Magnetic resonance imaging appearance of partial latissimus dorsi muscle tendon tear

    International Nuclear Information System (INIS)

    Le, Huy B.Q.; Lee, Steven T.; Lane, Michael D.; Munk, Peter L.; Malfair, David; Blachut, Piotr A.

    2009-01-01

    There is still a paucity of information about the clinical presentation, treatment and imaging findings of latissimus muscle tears. Only one study has specifically described the magnetic resonance imaging (MRI) features of latissimus tendon tears. We describe a case of a high-grade tear in the latissimus muscle tendon in an active water skier with no significant prior medical history. MRI demonstrated at least a 50% tear of the latissimus tendon, manifesting as increased signal intensity on T2-weighted sequences and surrounding edema, as well as a diminutive tendon at the humeral insertion. (orig.)

  17. Muscle-tendon-related pain in 100 patients with hip dysplasia: prevalence and associations with self-reported hip disability and muscle strength

    DEFF Research Database (Denmark)

    Jacobsen, Julie Sandell; Hölmich, Per; Thorborg, Kristian

    2017-01-01

    The primary aim was to identify muscle-tendon-related pain in 100 patients with hip dysplasia. The secondary aim was to test whether muscle-tendon-related pain is associated with self-reported hip disability and muscle strength in patient with hip dysplasia. One hundred patients (17 men......-tendon-related pain and hip extension a significant inverse linear association between muscletendon- related pain and muscle strength was found ranging from 0.11 to0.12 Nm/kg in the adjusted analysis (Phip dysplasia with a high prevalence......) with a mean age of 29 years (SD 9) were included. Clinical entity approach was carried out to identify muscle-tendon-related pain. Associations between muscle-tendon-related pain and self-reported hip disability and muscle strength were tested with multiple regression analysis, including adjustments for age...

  18. Rat rotator cuff muscle responds differently from hindlimb muscle to a combined tendon-nerve injury.

    Science.gov (United States)

    Davies, Michael R; Ravishankar, Bharat; Laron, Dominique; Kim, Hubert T; Liu, Xuhui; Feeley, Brian T

    2015-07-01

    Rotator cuff tears (RCTs) are among the most common musculoskeletal injuries seen by orthopaedic surgeons. Clinically, massive cuff tears lead to unique pathophysiological changes in rotator cuff muscle, including atrophy, and massive fatty infiltration, which are rarely seen in other skeletal muscles. Studies in a rodent model for RCT have demonstrated that these histologic findings are accompanied by activation of the Akt/mammalian target of rapamycin (mTOR) and transforming growth factor-β (TGF-β) pathways following combined tendon-nerve injury. The purpose of this study was to compare the histologic and molecular features of rotator cuff muscle and gastrocnemius muscle--a major hindlimb muscle, following combined tendon-nerve injury. Six weeks after injury, the rat gastrocnemius did not exhibit notable fatty infiltration compared to the rotator cuff. Likewise, the adipogenic markers SREBP-1 and PPARγ as well as the TGF-β canonical pathway were upregulated in the rotator cuff, but not the gastrocnemius. Our study suggests that the rat rotator cuff and hindlimb muscles differ significantly in their response to a combined tendon-nerve injury. Clinically, these findings highlight the unique response of the rotator cuff to injury, and may begin to explain the poor outcomes of massive RCTs compared to other muscle-tendon injuries. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  19. Immediate effects of hamstring stretching alone or combined with ischemic compression of the masseter muscle on hamstrings extensibility, active mouth opening and pain in athletes with temporomandibular dysfunction.

    Science.gov (United States)

    Espejo-Antúnez, Luis; Castro-Valenzuela, Elisa; Ribeiro, Fernando; Albornoz-Cabello, Manuel; Silva, Anabela; Rodríguez-Mansilla, Juan

    2016-07-01

    To assess the immediate effects of hamstrings stretching alone or combined with ischemic compression of the masseter muscle on hamstrings extensibility, active mouth opening and pain in athletes with temporomandibular dysfunction and hamstrings shortening. Forty-two participants were randomized to receive the stretching technique (n = 21) or the stretching plus the ischemic compression (n = 21). Outcome measures were: hamstrings extensibility, active mouth opening, pressure pain thresholds and pain intensity. Both interventions improved significantly active mouth opening (group 1: 35.7 ± 6.7 to 39.1 ± 7.6 mm, p Hamstrings stretching induced an acute improvement in hamstrings extensibility, active mouth opening and pain. Moreover, the addition of ischemic compression did not induce further improvements on the assessed parameters. Copyright © 2016. Published by Elsevier Ltd.

  20. Effect of administration of oral contraceptives in vivo on collagen synthesis in tendon and muscle connective tissue in young women

    DEFF Research Database (Denmark)

    Hansen, M; Miller, B F; Holm, L

    2009-01-01

    concentrations of estradiol and progesterone (control, n = 12). Subjects performed 1 h of one-legged kicking exercise. The next day collagen fractional synthesis rates (FSR) in tendon and muscle connective tissue were measured after a flooding dose of [(13)C]proline followed by biopsies from the patellar tendon......, body composition, and exercise-training status were included. The two groups were either habitual users of oral contraceptives exposed to a high concentration of synthetic estradiol and progestogens (OC, n = 11), or non-OC-users tested in the follicular phase of the menstrual cycle characterized by low...... bioavailability of IGF-I in OC. In conclusion, synthetic female sex hormones administered as OC had an inhibiting effect on collagen synthesis in tendon, bone, and muscle connective tissue, which may be related to a lower bioavailability of IGF-I....

  1. Validity and Reliability of a New Device (WIMU®) for Measuring Hamstring Muscle Extensibility.

    Science.gov (United States)

    Muyor, José M

    2017-09-01

    The aims of the current study were 1) to evaluate the validity of the WIMU ® system for measuring hamstring muscle extensibility in the passive straight leg raise (PSLR) test using an inclinometer for the criterion and 2) to determine the test-retest reliability of the WIMU ® system to measure hamstring muscle extensibility during the PSLR test. 55 subjects were evaluated on 2 separate occasions. Data from a Unilever inclinometer and WIMU ® system were collected simultaneously. Intraclass correlation coefficients (ICCs) for the validity were very high (0.983-1); a very low systematic bias (-0.21°--0.42°), random error (0.05°-0.04°) and standard error of the estimate (0.43°-0.34°) were observed (left-right leg, respectively) between the 2 devices (inclinometer and the WIMU ® system). The R 2 between the devices was 0.999 (p<0.001) in both the left and right legs. The test-retest reliability of the WIMU ® system was excellent, with ICCs ranging from 0.972-0.995, low coefficients of variation (0.01%), and a low standard error of the estimate (0.19-0.31°). The WIMU ® system showed strong concurrent validity and excellent test-retest reliability for the evaluation of hamstring muscle extensibility in the PSLR test. © Georg Thieme Verlag KG Stuttgart · New York.

  2. The effect of platelet rich plasma from bone marrow aspirate with added bone morphogenetic protein-2 on the Achilles tendon-bone junction in rabbits.

    Science.gov (United States)

    Kim, Hak Jun; Nam, Hyok-Woo; Hur, Chang-Yong; Park, Misu; Yang, Hee Seok; Kim, Byung-Soo; Park, Jung-Ho

    2011-12-01

    To determine if exogenously injected bone marrow derived platelet-rich plasma (PRP) plus bone morphogenetic protein (BMP)-2 could accelerate the healing of bone-tendon junction injuries and increase the junction holding strength during the early regeneration period. A direct injury model of the bone-tendon junction was made using an Achilles tendon-calcaneus bone junction in a rabbit. In the PRP/BMP-2/fibrin group, 0.05 mL of bone marrow derived PRP and 100 ng/mL of BMP-2 both incorporated into 0.1 mL of fibrin glue were injected into Achilles tendon-calcaneus bone junctions. The effect of the intervention was tested by comparing the results of an intervention group to a control group. The results of biomechanical testing, and histological and gross analyses were compared between the 2 groups at the following time points after surgery: 2 weeks, 4 weeks, and 8 weeks. Histologic examinations showed that woven bone developed in tendon-bone junctions at 2 weeks after surgery in the PRP/BMP-2/fibrin group. Mechanical test results showed no significant difference between the PRP/BMP-2/fibrin and control groups at 2 and 4 weeks after surgery, but the mean maximal load in the PRP/BMP-2/fibrin group was significantly higher than in the control group (p rabbit model of tendon-bone junction injury.

  3. Injury to the Infrapatellar Branch of the Saphenous Nerve during ACL Reconstruction with Hamstring Tendon Autograft: A Comparison between Oblique and Vertical Incisions

    Directory of Open Access Journals (Sweden)

    Hamid Mousavi

    2018-01-01

    Full Text Available Background: Injury to the infrapatellar branch of the saphenous nerve (IPBSN is common after arthroscopic ACLreconstruction with hamstring tendon autograft, as reported in up to 88% of the cases. Due to close relationshipbetween the IPBSN with pes anserine tendons insertion skin incision may sever IPBSN while harvesting gracillis andsemitendinous tendons. As the IPBSN course at the anterior of knee is oblique, we hypothesized a parallel skin incisionwith nerve passage may decrease nerve injury.Methods: Vertical and oblique incisions were compared in 79 patients in this clinical trial. The sensory loss area andpatients’ complain of numbness were measured at 2 and 8 weeks as well as 6 months after surgery.Results: Both the sensory loss area and patients’ complain of numbness decreased significantly in the oblique incisiongroup (P

  4. Corticospinal excitability changes following prolonged muscle tendon vibration

    NARCIS (Netherlands)

    Steyvers, M.; Levin, O.; Baelen, M.G.M. van; Swinnen, S.P.

    2003-01-01

    The present experiment addressed the time course of corticospinal excitability changes following interventional muscle tendon vibration. Using transcranial magnetic stimulation, motor evoked potentials of the flexor carpi radialis and extensor carpi radialis brevis muscle were recorded for a period

  5. Examination and Treatment of Hamstring Related Injuries

    Science.gov (United States)

    2012-01-01

    Context: There is a wide spectrum of hamstring-related injuries that can occur in the athlete. Accurate diagnosis is imperative to prevent delayed return to sport, injury recurrence, and accurate clinical decision making regarding the most efficacious treatment. Evidence Acquisition: This review highlights current evidence related to the diagnosis and treatment of hamstring-related injuries in athletes. Data sources were limited to peer-reviewed publications indexed in MEDLINE from 1988 through May 2011. Results: An accurate diagnostic process for athletes with posterior thigh–related complaints should include a detailed and discriminative history, followed by a thorough clinical examination. Diagnostic imaging should be utilized when considering hamstring avulsion or ischial apophyseal avulsion. Diagnostic imaging may also be needed to further define the cause of referred posterior thigh pain. Conclusions: Differentiating acute hamstring strains, hamstring tendon avulsions, ischial apophyseal avulsions, proximal hamstring tendinopathies, and referred posterior thigh pain is critical in determining the most appropriate treatment and expediting safe return to play. PMID:23016076

  6. Articular Cartilage Increases Transition Zone Regeneration in Bone-tendon Junction Healing

    Science.gov (United States)

    Qin, Ling; Lee, Kwong Man; Leung, Kwok Sui

    2008-01-01

    The fibrocartilage transition zone in the direct bone-tendon junction reduces stress concentration and protects the junction from failure. Unfortunately, bone-tendon junctions often heal without fibrocartilage transition zone regeneration. We hypothesized articular cartilage grafts could increase fibrocartilage transition zone regeneration. Using a goat partial patellectomy repair model, autologous articular cartilage was harvested from the excised distal third patella and interposed between the residual proximal two-thirds bone fragment and tendon during repair in 36 knees. We evaluated fibrocartilage transition zone regeneration, bone formation, and mechanical strength after repair at 6, 12, and 24 weeks and compared them with direct repair. Autologous articular cartilage interposition resulted in more fibrocartilage transition zone regeneration (69.10% ± 14.11% [mean ± standard deviation] versus 8.67% ± 7.01% at 24 weeks) than direct repair at all times. There was no difference in the amount of bone formation and mechanical strength achieved. Autologous articular cartilage interposition increases fibrocartilage transition zone regeneration in bone-tendon junction healing, but additional research is required to ascertain the mechanism of stimulation and to establish the clinical applicability. PMID:18987921

  7. Assessment of the mechanical properties of the muscle-tendon unit by supersonic shear wave imaging elastography: a review

    Directory of Open Access Journals (Sweden)

    Kelly Mônica Marinho e Lima

    2018-01-01

    Full Text Available This review aimed to describe the state of the art in muscle-tendon unit (MTU assessment by supersonic shear wave imaging (SSI elastography in states of muscle contraction and stretching, during aging, and in response to injury and therapeutic interventions. A consensus exists that MTU elasticity increases during passive stretching or contraction, and decreases after static stretching, electrostimulation, massage, and dry needling. There is currently no agreement regarding changes in the MTU due to aging and injury. Currently, the application of SSI for the purpose of diagnosis, rehabilitation, and physical training remains limited by a number of issues, including the lack of normative value ranges, the lack of consensus regarding the appropriate terminology, and an inadequate understanding of the main technical limitations of this novel technology.

  8. Hamstring muscle length and lumbar lordosis in subjects with different lifestyle and work setting: comparison between individuals with and without chronic low back pain.

    Science.gov (United States)

    Arab, Amir Massoud; Nourbakhsh, Mohammad Reza

    2014-01-01

    Shortened hamstring muscle length has been noted in persons with low back pain (LBP). Prolonged sitting postures, such as those adopted during different work settings and sedentary lifestyle has been associated with hamstring shortness and LBP. The purpose of this study was to investigate the effect of lifestyle and work setting on hamstring length and lumbar lordosis in subjects with and without LBP and to identify the relationship between hamstring muscles length and lumbar lordosis in individuals with different lifestyle and work setting. A total of 508 subjects between the ages of 20 and 65 were selected. Subjects were categorized into two groups of individuals with and without LBP. A questionnaire was used to obtain information about the subjects' lifestyle and work setting. Hamstring muscle length and lumbar lordosis were measured in all subjects. The results showed no significant difference in the number of subjects with different work setting or lifestyle in individuals with and without LBP. Hamstring muscle length or lumbar lordosis was not affected by type of work setting and lifestyle. Our data showed significant difference in hamstring length and no significant difference in lumbar lordosis between subjects with and without LBP in all categories. Lumbar lordosis was not different between individuals with and without hamstring tightness in normal and LBP subjects with different work setting and lifestyle. The findings of this study did not support the assumption that work setting and sedentary lifestyle would lead to hamstring tightness in subjects with LBP. It seems that work setting and lifestyle was not a contributing factor for hamstring tightness in subjects with LBP.

  9. Coordinated development of muscles and tendon-like structures: early interactions in the Drosophila leg

    Directory of Open Access Journals (Sweden)

    cedric esoler

    2016-02-01

    Full Text Available The formation of the musculoskeletal system is a remarkable example of tissue assembly. In both vertebrates and invertebrates, precise connectivity between muscles and skeleton (or exoskeleton via tendons or equivalent structures is fundamental for movement and stability of the body. The molecular and cellular processes underpinning muscle formation are well established and significant advances have been made in understanding tendon development. However, the mechanisms contributing to proper connection between these two tissues have received less attention. Observations of coordinated development of tendons and muscles suggest these tissues may interact during the different steps in their development. There is growing evidence that, depending on animal model and muscle type, these interactions can take place from progenitor induction to the final step of the formation of the musculoskeletal system. Here we briefly review and compare the mechanisms behind muscle and tendon interaction throughout the development of vertebrates and Drosophila before going on to discuss our recent findings on the coordinated development of muscles and tendon-like structures in Drosophila leg. By altering apodeme formation (the functional Drosophila equivalent of tendons in vertebrates during the early steps of leg development, we affect the spatial localisation of subsequent myoblasts. These findings provide the first evidence of the developmental impact of early interactions between muscle and tendon-like precursors, and confirm the appendicular Drosophila muscle system as a valuable model for studying these processes.

  10. Is passive stiffness in human muscles related to the elasticity of tendon structures?

    Science.gov (United States)

    Kubo, K; Kanehisa, H; Fukunaga, T

    2001-08-01

    The purpose of this study was to examine in vivo whether passive stiffness in human muscles was related to the elasticity of tendon structures and to performance during stretch-shortening cycle exercise. Passive torque of plantar flexor muscles was measured during passive stretch from 90 degrees (anatomical position) to 65 degrees of dorsiflexion at a constant velocity of 5 degrees.s-1. The slope of the linear portion of the passive torque-angle curve during stretching was defined as the passive stiffness of the muscle. The elongation of the tendon and aponeurosis of the medial gastrocnemius muscle (MG) was directly measured using ultrasonography during ramp isometric plantar flexion up to the voluntary maximum. The relationship between the estimated muscle force of MG and tendon elongation was fitted to a linear regression, the slope of which was defined as the stiffness of the tendon. In addition, the dynamic torques during maximal voluntary concentric plantar flexion with and without prior eccentric contraction were determined at a constant velocity of 120 degrees.s-1. There were no significant correlations between passive stiffness and either the tendon stiffness (r = 0.19, P > 0.05) or the relative increase in torque with prior eccentric contraction (r = -0.19, P > 0.05). However, tendon stiffness was negatively correlated to the relative increase in torque output (r = -0.42, P tendon structures, and had no favourable effect on the muscle performance during stretch-shortening cycle exercise.

  11. Functional grading of mineral and collagen in the attachment of tendon to bone.

    Science.gov (United States)

    Genin, Guy M; Kent, Alistair; Birman, Victor; Wopenka, Brigitte; Pasteris, Jill D; Marquez, Pablo J; Thomopoulos, Stavros

    2009-08-19

    Attachment of dissimilar materials is a major challenge because high levels of localized stress may develop at their interfaces. An effective biologic solution to this problem exists at one of nature's most extreme interfaces: the attachment of tendon (a compliant, structural "soft tissue") to bone (a stiff, structural "hard tissue"). The goal of our study was to develop biomechanical models to describe how the tendon-to-bone insertion derives its mechanical properties. We examined the tendon-to-bone insertion and found two factors that give the tendon-to-bone transition a unique grading in mechanical properties: 1), a gradation in mineral concentration, measured by Raman spectroscopy; and 2), a gradation in collagen fiber orientation, measured by polarized light microscopy. Our measurements motivate a new physiological picture of the tissue that achieves this transition, the tendon-to-bone insertion, as a continuous, functionally graded material. Our biomechanical model suggests that the experimentally observed increase in mineral accumulation within collagen fibers can provide significant stiffening of the partially mineralized fibers, but only for concentrations of mineral above a "percolation threshold" corresponding to formation of a mechanically continuous mineral network within each collagen fiber (e.g., the case of mineral connectivity extending from one end of the fiber to the other). Increasing dispersion in the orientation distribution of collagen fibers from tendon to bone is a second major determinant of tissue stiffness. The combination of these two factors may explain the nonmonotonic variation of stiffness over the length of the tendon-to-bone insertion reported previously. Our models explain how tendon-to-bone attachment is achieved through a functionally graded material composition, and provide targets for tissue engineered surgical interventions and biomimetic material interfaces.

  12. Development and evaluation of a removable tissue-engineered muscle with artificial tendons.

    Science.gov (United States)

    Nakamura, Tomohiro; Takagi, Shunya; Kamon, Takafumi; Yamasaki, Ken-Ichi; Fujisato, Toshia

    2017-02-01

    Tissue-engineered skeletal muscles were potentially useful as physiological and biochemical in vitro models. Currently, most of the similar models were constructed without tendons. In this study, we aimed to develop a simple, highly versatile tissue-engineered muscle with artificial tendons, and to evaluate the contractile, histological and molecular dynamics during differentiation. C2C12 cells were embedded in a cold type-І collagen gel and placed between two artificial tendons on a silicone sheet. The construct shrank and tightly attached to the artificial tendons with differentiation, finally detaching from the silicone sheet within 1 week of culture onset. We successfully developed a tissue-engineered skeletal muscle with two artificial tendons from C2C12 myoblasts embedded in type-І collagen gel. The isometric twitch contractile force (TCF) significantly increased during differentiation. Time to Peak Tension (TPT) and Half-Relaxation Time (1/2RT) were significantly shortened during differentiation. Myogenic regulatory factors were maximally expressed at 2 weeks, and subsequently decreased at 3 weeks of culture. Histological analysis indicated that myotube formation increased markedly from 2 weeks and well-ordered sarcomere structures were observed on the surface of the 3D engineered muscle at 3 weeks of culture. These results suggested that robust muscle structure occurred by 3 weeks in the tissue-engineered skeletal muscle. Moreover, during the developmental process, the artificial tendons might contribute to well-ordered sarcomere formation. Our results indicated that this simple culture system could be used to evaluate the effects of various pharmacological and mechanical cues on muscle contractility in a variety of research areas. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  13. Effects of Inclined Treadmill Walking on Pelvic Anterior Tilt Angle, Hamstring Muscle Length, and Trunk Muscle Endurance of Seated Workers with Flat-back Syndrome.

    Science.gov (United States)

    Kim, Min-Hee; Yoo, Won-Gyu

    2014-06-01

    [Purpose] This study investigated the effects of inclined treadmill walking on pelvic anterior tilt angle, hamstring muscle length, and back muscle endurance of seated workers with flat-back syndrome. [Subjects] Eight seated workers with flat-back syndrome who complained of low-back pain in the L3-5 region participated in this study. [Methods] The subjects performed a walking exercise on a 30° inclined treadmill. We measured the pelvic anterior tilt angle, hamstring muscle length, and back muscle endurance before and after inclined treadmill walking. [Results] Anterior pelvic tilt angle and active knee extension angle significantly increased after inclined treadmill walking. Trunk extensor and flexor muscle endurance times were also significantly increased compared to the baseline. [Conclusion] Inclined treadmill walking may be an effective approach for the prevention or treatment of low-back pain in flat-back syndrome.

  14. Effects of plyometric and isometric training on muscle and tendon stiffness in vivo.

    Science.gov (United States)

    Kubo, Keitaro; Ishigaki, Tomonobu; Ikebukuro, Toshihiro

    2017-08-01

    The purpose of this study was to compare the effects of plyometric and isometric training on tendon properties during ramp and ballistic contractions and muscle stiffness under passive and active conditions. Eleven subjects completed 12 weeks (3 days/week) of a unilateral training program for the plantar flexors. They performed plyometric training on one side (PLY) and isometric training on the other side (ISO). Active muscle stiffness in the medial gastrocnemius muscle was calculated according to changes in estimated muscle force and fascicle length during fast stretching after submaximal isometric contractions. Passive muscle stiffness was also calculated from estimated passive muscle force and fascicle length during slow passive stretching. Stiffness and hysteresis of tendon structures were measured using ultrasonography during ramp and ballistic contractions. Passive muscle stiffness and tendon hysteresis did not change for PLY or ISO Active muscle stiffness significantly increased for PLY, but not for ISO Tendon stiffness during ramp and ballistic contractions increased significantly for ISO, but not for PLY In addition, tendon elongation values at force production levels beyond 100 N during ballistic contractions increased for PLY These results suggest that plyometric training (but not isometric training) enhances the extensibility of tendon structures during ballistic contractions and active muscle stiffness during fast stretching, and these changes may be related to improved performances during stretch-shortening cycle exercises. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  15. Inhibition of 5-LOX, COX-1, and COX-2 increases tendon healing and reduces muscle fibrosis and lipid accumulation after rotator cuff repair.

    Science.gov (United States)

    Oak, Nikhil R; Gumucio, Jonathan P; Flood, Michael D; Saripalli, Anjali L; Davis, Max E; Harning, Julie A; Lynch, Evan B; Roche, Stuart M; Bedi, Asheesh; Mendias, Christopher L

    2014-12-01

    The repair and restoration of function after chronic rotator cuff tears are often complicated by muscle atrophy, fibrosis, and fatty degeneration of the diseased muscle. The inflammatory response has been implicated in the development of fatty degeneration after cuff injuries. Licofelone is a novel anti-inflammatory drug that inhibits 5-lipoxygenase (5-LOX), as well as cyclooxygenase (COX)-1 and COX-2 enzymes, which play important roles in inducing inflammation after injuries. While previous studies have demonstrated that nonsteroidal anti-inflammatory drugs and selective inhibitors of COX-2 (coxibs) may prevent the proper healing of muscles and tendons, studies about bone and cartilage have demonstrated that drugs that inhibit 5-LOX concurrently with COX-1 and COX-2 may enhance tissue regeneration. After the repair of a chronic rotator cuff tear in rats, licofelone would increase the load to failure of repaired tendons and increase the force production of muscle fibers. Controlled laboratory study. Rats underwent supraspinatus release followed by repair 28 days later. After repair, rats began a treatment regimen of either licofelone or a vehicle for 14 days, at which time animals were euthanized. Supraspinatus muscles and tendons were then subjected to contractile, mechanical, histological, and biochemical analyses. Compared with controls, licofelone-treated rats had a grossly apparent decrease in inflammation and increased fibrocartilage formation at the enthesis, along with a 62% increase in the maximum load to failure and a 51% increase in peak stress to failure. Licofelone resulted in a marked reduction in fibrosis and lipid content in supraspinatus muscles as well as reduced expression of several genes involved in fatty infiltration. Despite the decline in fibrosis and fat accumulation, muscle fiber specific force production was reduced by 23%. The postoperative treatment of cuff repair with licofelone may reduce fatty degeneration and enhance the development

  16. Stretching Your Energetic Budget: How Tendon Compliance Affects the Metabolic Cost of Running.

    Directory of Open Access Journals (Sweden)

    Thomas K Uchida

    Full Text Available Muscles attach to bones via tendons that stretch and recoil, affecting muscle force generation and metabolic energy consumption. In this study, we investigated the effect of tendon compliance on the metabolic cost of running using a full-body musculoskeletal model with a detailed model of muscle energetics. We performed muscle-driven simulations of running at 2-5 m/s with tendon force-strain curves that produced between 1 and 10% strain when the muscles were developing maximum isometric force. We computed the average metabolic power consumed by each muscle when running at each speed and with each tendon compliance. Average whole-body metabolic power consumption increased as running speed increased, regardless of tendon compliance, and was lowest at each speed when tendon strain reached 2-3% as muscles were developing maximum isometric force. When running at 2 m/s, the soleus muscle consumed less metabolic power at high tendon compliance because the strain of the tendon allowed the muscle fibers to operate nearly isometrically during stance. In contrast, the medial and lateral gastrocnemii consumed less metabolic power at low tendon compliance because less compliant tendons allowed the muscle fibers to operate closer to their optimal lengths during stance. The software and simulations used in this study are freely available at simtk.org and enable examination of muscle energetics with unprecedented detail.

  17. [Avulsion of the Proximal Hamstring Insertion. Case Reports].

    Science.gov (United States)

    Mizera, R; Harcuba, R; Kratochvíl, J

    2016-01-01

    Proximal hamstring avulsion is an uncommon muscle injury with a lack of consensus on indications and the timing and technique of surgery. Poor clinical symptoms and difficulties in the diagnostic process can lead to a false diagnosis. The authors present three cases of proximal hamstring avulsion, two complete and one partial ruptures of the biceps femoris muscle. MRI and ultrasound scans were used for optimal treatment alignment. Acute surgery reconstruction (hamstring strength. Two interesting systematic reviews published on the treatment of proximal hamstring avulsion are discussed in the final part of the paper. Key words: hamstring, rupture, avulsion.

  18. Effects of 12-wk eccentric calf muscle training on muscle-tendon glucose uptake and SEMG in patients with chronic Achilles tendon pain.

    Science.gov (United States)

    Masood, Tahir; Kalliokoski, Kari; Magnusson, S Peter; Bojsen-Møller, Jens; Finni, Taija

    2014-07-15

    High-load eccentric exercises have been a key component in the conservative management of chronic Achilles tendinopathy. This study investigated the effects of a 12-wk progressive, home-based eccentric rehabilitation program on ankle plantar flexors' glucose uptake (GU) and myoelectric activity and Achilles tendon GU. A longitudinal study design with control (n = 10) and patient (n = 10) groups was used. Surface electromyography (SEMG) from four ankle plantar flexors and GU from the same muscles and the Achilles tendon were measured during submaximal intermittent isometric plantar flexion task. The results indicated that the symptomatic leg was weaker (P eccentric rehabilitation. Additionally, the rehabilitation resulted in greater GU in both soleus (P tendon GU than the controls (P effect on the tendon GU. Concerning SEMG, at baseline, soleus showed more relative activity in the symptomatic leg compared with both the asymptomatic and control legs (P Eccentric rehabilitation was effective in decreasing subjective severity of Achilles tendinopathy. It also resulted in redistribution of relative electrical activity, but not metabolic activity, within the triceps surae muscle. Copyright © 2014 the American Physiological Society.

  19. Dynamic adaptation of tendon and muscle connective tissue to mechanical loading

    DEFF Research Database (Denmark)

    Mackey, Abigail; Heinemeier, Katja Maria; Koskinen, Satu Osmi Anneli

    2008-01-01

    The connective tissue of tendon and skeletal muscle is a crucial structure for force transmission. A dynamic adaptive capacity of these tissues in healthy individuals is evident from reports of altered gene expression and protein levels of the fibrillar and network-forming collagens, when subjected...... in this article provide strong evidence for the highly adaptable nature of connective tissue in muscle and tendon....

  20. The effect of targeted exercise on knee-muscle function in patients with persistent hamstring deficiency following ACL reconstruction

    DEFF Research Database (Denmark)

    Bregenhof, Bo; Jørgensen, Uffe; Aagaard, Per

    2018-01-01

    BACKGROUND: Anterior cruciate ligament (ACL) reconstruction, using hamstring auto-graft is a common surgical procedure, which often leads to persistent hamstring muscle-strength deficiency and reduced function. The purpose of this randomized controlled trial (RCT) is to investigate the effect...... at 12-24 months' post surgery, will be recruited through outpatient clinics and advertisements. Patients will be randomized to a 12-week progressive, strength and neuromuscular exercise group (SNG) with supervised training twice weekly or a control intervention (CON) consisting of a home-based, low......-intensity exercise program. Outcome measures include between-group change in maximal isometric knee-flexor strength (primary outcome) and knee-extensor muscle strength, hamstring-to-quadriceps strength ratios of the leg that has been operated on and Knee injury and Osteoarthritis Outcome Score (KOOS) (secondary...

  1. Multifunctional magnetic-responsive hydrogels to engineer tendon-to-bone interface.

    Science.gov (United States)

    Silva, Elsa D; Babo, Pedro S; Costa-Almeida, Raquel; Domingues, Rui M A; Mendes, Bárbara B; Paz, Elvira; Freitas, Paulo; Rodrigues, Márcia T; Granja, Pedro L; Gomes, Manuela E

    2017-06-11

    Photocrosslinkable magnetic hydrogels are attracting great interest for tissue engineering strategies due to their versatility and multifunctionality, including their remote controllability ex vivo, thus enabling engineering complex tissue interfaces. This study reports the development of a photocrosslinkable magnetic responsive hydrogel made of methacrylated chondroitin sulfate (MA-CS) enriched with platelet lysate (PL) with tunable features, envisioning their application in tendon-to-bone interface. MA-CS coated iron-based magnetic nanoparticles were incorporated to provide magnetic responsiveness to the hydrogel. Osteogenically differentiated adipose-derived stem cells and/or tendon-derived cells were encapsulated within the hydrogel, proliferating and expressing bone- and tendon-related markers. External magnetic field (EMF) application modulated the swelling, degradation and release of PL-derived growth factors, and impacted both cell morphology and the expression and synthesis of tendon- and bone-like matrix with a more evident effect in co-cultures. Overall, the developed magnetic responsive hydrogel represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. The Effect of Antagonist Muscle Sensory Input on Force Regulation.

    Directory of Open Access Journals (Sweden)

    Tanya Onushko

    Full Text Available The purpose of this study was to understand how stretch-related sensory feedback from an antagonist muscle affects agonist muscle output at different contraction levels in healthy adults. Ten young (25.3 ± 2.4 years, healthy subjects performed constant isometric knee flexion contractions (agonist at 6 torque levels: 5%, 10%, 15%, 20%, 30%, and 40% of their maximal voluntary contraction. For half of the trials, subjects received patellar tendon taps (antagonist sensory feedback during the contraction. We compared error in targeted knee flexion torque and hamstring muscle activity, with and without patellar tendon tapping, across the 6 torque levels. At lower torque levels (5%, 10%, and 15%, subjects produced greater knee torque error following tendon tapping compared with the same torque levels without tendon tapping. In contrast, we did not find any difference in torque output at higher target levels (20%, 30%, and 40% between trials with and without tendon tapping. We also observed a load-dependent increase in the magnitude of agonist muscle activity after tendon taps, with no associated load-dependent increase in agonist and antagonist co-activation, or reflex inhibition from the antagonist tapping. The findings suggest that at relatively low muscle activity there is a deficiency in the ability to correct motor output after sensory disturbances, and cortical centers (versus sub-cortical are likely involved.

  3. Extrusion of bone anchor suture following flexor digitorum profundus tendon avulsion injury repair.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2011-09-01

    Flexor digitorum profundus (FDP) zone I tendon avulsion injury is traditionally repaired with a pullout suture technique. More recently, bone anchor sutures have been used as a viable alternative and have largely replaced areas in hand surgery where pullout suture technique was once required. To date, there have been very few complications reported related to bone anchor suture use in FDP tendon reattachment to the bone. We report a very unusual case of extrusion of bone anchor through the nailbed, 6 years after zone I FDP tendon avulsion injury repair and a brief review of literature.

  4. Mechanisms of proximal hamstring rupture in a non-athlete healthy middle-aged female.

    Science.gov (United States)

    Cotofana, Sebastian; Tillman, Bernhard; Pufe, Thomas; Lehrer, Selim; Watz, Dorothee; Zangl, Monika; Modlmayr, Harald; Knöckl, Ernest; Mahn, Hans-Joachim; Wambach, Werner

    2012-09-01

    To present an explicatory pathophysiological model for the rare clinical case of a total proximal hamstring rupture for the first time in the literature. A non-athletic healthy female (49 years) experienced a complete rupture of the right conjoint tendon of the biceps femoris (long head) and semitendinosus muscle while slipping down a lawn-covered slope (eccentric hip flexion and knee extension during stance phase of gait after heel-strike). A hamstring rupture was diagnosed by clinical examination and confirmed by magnet resonance imaging (MRI). Surgical reattachment of the conjoint tendon to the ischial tuberosity was performed. One year after surgery, she experienced no pain or functional impairment. Histological analysis and immune-histochemical staining (vascular endothelial growth factor - receptor 2) of a biopsy taken intra-operatively revealed signs of fibroblast proliferation and vasculoneogenesis with absence of inflammatory changes indicating that repairing mechanisms and tissue remodeling had been taking place. This case report provides evidence for the hypothesis that micro-injuries induce repairing mechanisms and thus tissue remodeling which leads to consecutive tissue weakening and mechanical failure during a non-adequate trauma. Micro-injuries can occur during leisure activities and remain clinically invisible until rupture. Copyright © 2012 Elsevier GmbH. All rights reserved.

  5. Region-dependent hamstrings activity in Nordic hamstring exercise and stiff-leg deadlift defined with high-density electromyography.

    Science.gov (United States)

    Hegyi, A; Péter, A; Finni, T; Cronin, N J

    2018-03-01

    Recent studies suggest region-specific metabolic activity in hamstring muscles during injury prevention exercises, but the neural representation of this phenomenon is unknown. The aim of this study was to examine whether regional differences are evident in the activity of biceps femoris long head (BFlh) and semitendinosus (ST) muscles during two common injury prevention exercises. Twelve male participants without a history of hamstring injury performed the Nordic hamstring exercise (NHE) and stiff-leg deadlift (SDL) while BFlh and ST activities were recorded with high-density electromyography (HD-EMG). Normalized activity was calculated from the distal, middle, and proximal regions in the eccentric phase of each exercise. In NHE, ST overall activity was substantially higher than in BFlh (d = 1.06 ± 0.45), compared to trivial differences between muscles in SDL (d = 0.19 ± 0.34). Regional differences were found in NHE for both muscles, with different proximal-distal patterns: The distal region showed the lowest activity level in ST (regional differences, d range = 0.55-1.41) but the highest activity level in BFlh (regional differences, d range = 0.38-1.25). In SDL, regional differences were smaller in both muscles (d range = 0.29-0.67 and 0.16-0.63 in ST and BFlh, respectively) than in NHE. The use of HD-EMG in hamstrings revealed heterogeneous hamstrings activity during typical injury prevention exercises. High-density EMG might be useful in future studies to provide a comprehensive overview of hamstring muscle activity in other exercises and high-injury risk tasks. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Abductor tendon tears are associated with hypertrophy of the tensor fasciae latae muscle.

    Science.gov (United States)

    Sutter, Reto; Kalberer, Fabian; Binkert, Christoph A; Graf, Nicole; Pfirrmann, Christian W A; Gutzeit, Andreas

    2013-05-01

    To evaluate the association between hypertrophy of the tensor fasciae latae muscle and abductor tendon tears. Thirty-five patients who underwent MRI of the abductor tendons of the hip were included in this retrospective study. A subgroup of 18 patients was examined bilaterally. The area of the tensor fasciae latae muscle and the area of the sartorius muscle (size reference) were quantified at the level of the femoral head, and a ratio was calculated. Two radiologists assessed the integrity of the gluteus medius and minimus tendon in consensus. Data were analyzed with a Mann-Whitney U test. Sixteen out of 35 patients (46 %) had a tear of the gluteus medius or minimus tendon. The ratio of the area of the tensor fasciae latae to the sartorius muscle was significantly higher (p = .028) in the group with an abductor tendon tear (median 2.25; Interquartile Range [IQR] = 1.97-3.21) compared to the group without any tears (median 1.91; IQR = 1.52-2.26). The bilateral subanalysis showed that in patients without a tear, the ratio of the two areas did not differ between each side (p = .966), with a median of 1.54 (primary side) and 1.76 (contralateral side). In patients with an abductor tendon tear the ratio was significantly higher (p = .031) on the side with a tear (median 2.81) compared to the contralateral healthy side (1.67). Patients with abductor tendon tears showed hypertrophy of the tensor fasciae latae muscle when compared to the contralateral healthy side and to patients without a tear.

  7. Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

    International Nuclear Information System (INIS)

    Ilaslan, Hakan; Recht, Michael P.; Iannotti, Joseph P.

    2007-01-01

    To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear. (orig.)

  8. Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

    Energy Technology Data Exchange (ETDEWEB)

    Ilaslan, Hakan; Recht, Michael P. [Cleveland Clinic, Musculoskeletal Radiology/A21, Division of Radiology, Cleveland, OH (United States); Iannotti, Joseph P. [Cleveland Clinic, Department of Orthopedic Surgery, Cleveland, OH (United States)

    2007-06-15

    To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear. (orig.)

  9. Determinants of Return to Play After the Nonoperative Management of Hamstring Injuries in Athletes: A Systematic Review.

    Science.gov (United States)

    Fournier-Farley, Camille; Lamontagne, Martin; Gendron, Patrick; Gagnon, Dany H

    2016-08-01

    It is important for clinicians to rely on suitable prognosis factors after hamstring injuries because of the high incidence of these injuries and time away from athletic activities. To summarize the current literature on factors that influence return to play after a hamstring injury in athletes. Systematic review. A computer-assisted literature search of CINAHL, MEDLINE, Embase, and EBM Reviews databases (and a manual search of the reference lists of all selected articles) was conducted using keywords related to hamstring injuries and return to play. The literature review criteria included (1) patients with an acute hamstring or posterior thigh injury; (2) a randomized controlled trial, cohort study, case-control study, case series, or prospective or retrospective design; (3) information on rehabilitation, physical therapy, clinical assessment, imaging techniques, and return to play; and (4) studies written in English or French. The search strategy identified 914 potential articles, of which 24 met the inclusion criteria. In terms of the clinical assessment, the following factors were associated with a longer recovery time: stretching-type injuries, recreational-level sports, structural versus functional injuries, greater range of motion deficit with the hip flexed at 90°, time to first consultation >1 week, increased pain on the visual analog scale, and >1 day to be able to walk pain free after the injury. As for magnetic resonance imaging studies, the following factors correlated with a longer recovery time: positive findings; higher grade of injury; muscle involvement >75%; complete transection; retraction; central tendon disruption of the biceps femoris; proximal tendon involvement; shorter distance to the ischial tuberosity; length of the hamstring injury; and depth, volume, and large cross-sectional area. With respect to ultrasound studies, the following factors were associated with a poor prognosis: large cross-sectional area, injury outside the

  10. Neuromuscular and muscle-tendon system adaptations to isotonic and isokinetic eccentric exercise.

    Science.gov (United States)

    Guilhem, G; Cornu, C; Guével, A

    2010-06-01

    To present the properties of an eccentric contraction and compare neuromuscular and muscle-tendon system adaptations induced by isotonic and isokinetic eccentric trainings. An eccentric muscle contraction is characterized by the production of muscle force associated to a lengthening of the muscle-tendon system. This muscle solicitation can cause micro lesions followed by a regeneration process of the muscle-tendon system. Eccentric exercise is commonly used in functional rehabilitation for its positive effect on collagen synthesis but also for resistance training to increase muscle strength and muscle mass in athletes. Indeed, eccentric training stimulates muscle hypertrophy, increases the fascicle pennation angle, fascicles length and neural activation, thus inducing greater strength gains than concentric or isometric training programs. Eccentric exercise is commonly performed either against a constant external load (isotonic) or at constant velocity (isokinetic), inducing different mechanical constraints. These different mechanical constraints could induce structural and neural adaptive strategies specific to each type of exercise. The literature tends to show that isotonic mode leads to a greater strength gain than isokinetic mode. This observation could be explained by a greater neuromuscular activation after IT training. However, the specific muscle adaptations induced by each mode remain difficult to determine due to the lack of standardized, comparative studies. 2010 Elsevier Masson SAS. All rights reserved.

  11. The Preventive Effect of the Nordic Hamstring Exercise on Hamstring Injuries in Amateur Soccer Players : A Randomized Controlled Trial

    NARCIS (Netherlands)

    van der Horst, Nick; Smits, Dirk-Wouter; Petersen, Jesper; Goedhart, Edwin A.; Backx, Frank J. G.

    Background: Hamstring injuries are the most common muscle injuries in soccer, and they have a high rate of recurrence. Eccentric hamstrings strength is recognized as an important modifiable risk factor. This led to the development of prevention exercises such as the nordic hamstring exercise (NHE).

  12. A Comparative Outcome Study of Hamstring Versus Tibialis Anterior and Synthetic Grafts for Deltoid to Triceps Transfers.

    Science.gov (United States)

    Dunn, Jennifer A; Mohammed, Khalid D; Beadel, Gordon P; Rothwell, Alastair G; Simcock, Jeremy W

    2017-10-01

    To assess elbow extension strength and complications after deltoid-triceps transfers using hamstring tendon graft compared with tibialis anterior and synthetic tendon grafts. A retrospective review of deltoid-triceps transfers in patients with tetraplegia performed between 1983 and 2014. Seventy-five people (136 arms) had surgery performed, with the majority undergoing simultaneous bilateral surgery (n = 61; 81%). Tibialis anterior tendon grafts were used in 68 arms, synthetic grafts in 23 arms, and hamstring tendon grafts in 45 arms. The average age at surgery was 31 years. Sixty-three arms (46%) were assessed between 12 and 24 months after surgery. Seventy percent of the group (n = 54) were able to extend their elbow against gravity (grade 3 of 5 or greater) following surgery. Seventy-nine percent of those with hamstring grafts achieved grade 3 of 5 or more compared with 77% with tibialis anterior and 33% with synthetic grafts. There was a statistically significant difference in postsurgery elbow extension between the tibialis anterior group and the synthetic graft group and the hamstring and the synthetic graft group but not between the tibialis anterior and the hamstring group. Complications occurred in 19 arms (14%), the majority occurring immediately after surgery and associated with the wounds. The remaining complications were with the synthetic graft group in which dehiscence of the proximal attachment occurred in 30% of the arms. Autologous tendon grafting is associated with achievement of antigravity elbow extension in a greater proportion of individuals than with prosthetic grafting. Therapeutic IV. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  13. GH receptor blocker administration and muscle-tendon collagen synthesis in humans

    DEFF Research Database (Denmark)

    Nielsen, Rie Harboe; Doessing, Simon; Goto, Kazushige

    2011-01-01

    The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis stimulates collagen synthesis in tendon and skeletal muscle, but no studies have investigated the effect of reducing IGF-I on collagen synthesis in healthy humans.......The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis stimulates collagen synthesis in tendon and skeletal muscle, but no studies have investigated the effect of reducing IGF-I on collagen synthesis in healthy humans....

  14. Muscle-tendon related pain in 100 patients with hip dysplasia: prevalence and associations with self-reported hip disability and muscle strength

    DEFF Research Database (Denmark)

    Jacobsen, Julie Sandell

    2017-01-01

    Introduction Intra-articular injury has been described as primary cause of pain in hip dysplasia. At this point, it is unknown whether external muscle-tendon related pain coexists with intra-articular pathology. The primary aim was to identify muscle-tendon related pain in 100 patients with hip...... dysplasia. The secondary aim was to test if muscle-tendon related pain is linearly associated to self-reported hip disability and muscle strength in patients with hip dysplasia. Materials and methods One hundred patients (17 men) with a mean age of 29+9 years were included. Clinical entity approach...... (phip dysplasia with a high...

  15. Mechanical Loading Improves Tendon-Bone Healing in a Rabbit Anterior Cruciate Ligament Reconstruction Model by Promoting Proliferation and Matrix Formation of Mesenchymal Stem Cells and Tendon Cells

    Directory of Open Access Journals (Sweden)

    Fanglong Song

    2017-02-01

    Full Text Available Background/Aims: This study investigated the effect of mechanical stress on tendon-bone healing in a rabbit anterior cruciate ligament (ACL reconstruction model as well as cell proliferation and matrix formation in co-culture of bone-marrow mesenchymal stem cells (BMSCs and tendon cells (TCs. Methods: The effect of continuous passive motion (CPM therapy on tendon-bone healing in a rabbit ACL reconstruction model was evaluated by histological analysis, biomechanical testing and gene expressions at the tendon-bone interface. Furthermore, the effect of mechanical stretch on cell proliferation and matrix synthesis in BMSC/TC co-culture was also examined. Results: Postoperative CPM therapy significantly enhanced tendon-bone healing, as evidenced by increased amount of fibrocartilage, elevated ultimate load to failure levels, and up-regulated gene expressions of Collagen I, alkaline phosphatase, osteopontin, Tenascin C and tenomodulin at the tendon-bone junction. In addition, BMSC/TC co-culture treated with mechanical stretch showed a higher rate of cell proliferation and enhanced expressions of Collagen I, Collagen III, alkaline phosphatase, osteopontin, Tenascin C and tenomodulin than that of controls. Conclusion: These results demonstrated that proliferation and differentiation of local precursor cells could be enhanced by mechanical stimulation, which results in enhanced regenerative potential of BMSCs and TCs in tendon-bone healing.

  16. Effects of low-intensity pulsed ultrasound on new trabecular bone during bone-tendon junction healing in a rabbit model: a synchrotron radiation micro-CT study.

    Directory of Open Access Journals (Sweden)

    Hongbin Lu

    Full Text Available This study was designed to evaluate the effects of low-intensity pulsed ultrasound on bone regeneration during the bone-tendon junction healing process and to explore the application of synchrotron radiation micro computed tomography in three dimensional visualization of the bone-tendon junction to evaluate the microarchitecture of new trabecular bone. Twenty four mature New Zealand rabbits underwent partial patellectomy to establish a bone-tendon junction injury model at the patella-patellar tendon complex. Animals were then divided into low-intensity pulsed ultrasound treatment (20 min/day, 7 times/week and placebo control groups, and were euthanized at week 8 and 16 postoperatively (n = 6 for each group and time point. The patella-patellar tendon specimens were harvested for radiographic, histological and synchrotron radiation micro computed tomography detection. The area of the newly formed bone in the ultrasound group was significantly greater than that of control group at postoperative week 8 and 16. The high resolution three dimensional visualization images of the bone-tendon junction were acquired by synchrotron radiation micro computed tomography. Low-intensity pulsed ultrasound treatment promoted dense and irregular woven bone formation at week 8 with greater bone volume fraction, number and thickness of new trabecular bone but with lower separation. At week 16, ultrasound group specimens contained mature lamellar bone with higher bone volume fraction and thicker trabeculae than that of control group; however, there was no significant difference in separation and number of the new trabecular bone. This study confirms that low-intensity pulsed ultrasound treatment is able to promote bone formation and remodeling of new trabecular bone during the bone-tendon junction healing process in a rabbit model, and the synchrotron radiation micro computed tomography could be applied for three dimensional visualization to quantitatively evaluate

  17. Effect of exercise-induced enhancement of the leg-extensor muscle-tendon unit capacities on ambulatory mechanics and knee osteoarthritis markers in the elderly.

    Science.gov (United States)

    Karamanidis, Kiros; Oberländer, Kai Daniel; Niehoff, Anja; Epro, Gaspar; Brüggemann, Gert-Peter

    2014-01-01

    Leg-extensor muscle weakness could be a key component in knee joint degeneration in the elderly because it may result in altered muscular control during locomotion influencing the mechanical environment within the joint. This work aimed to examine whether an exercise-induced enhancement of the triceps surae (TS) and quadriceps femoris (QF) muscle-tendon unit (MTU) capacities would affect mechanical and biological markers for knee osteoarthritis in the elderly. Twelve older women completed a 14-week TS and QF MTU exercise intervention, which had already been established as increasing muscle strength and tendon stiffness. Locomotion mechanics and serum cartilage oligomeric matrix protein (COMP) levels were examined during incline walking. MTU mechanical properties were assessed using simultaneously ultrasonography and dynamometry. Post exercise intervention, the elderly had higher TS and QF contractile strength and tendon-aponeurosis stiffness. Regarding the incline gait task, the subjects demonstrated a lower external knee adduction moment and lower knee adduction angular impulse during the stance phase post-intervention. Furthermore, post-intervention compared to pre-intervention, the elderly showed lower external hip adduction moment, but revealed higher plantarflexion pushoff moment. The changes in the external knee adduction moment were significantly correlated with the improvement in ankle pushoff function. Serum COMP concentration increased in response to the 0.5-h incline walking exercise with no differences in the magnitude of increment between pre- and post-intervention. This work emphasizes the important role played by the ankle pushoff function in knee joint mechanical loading during locomotion, and may justify the inclusion of the TS MTU in prevention programs aiming to positively influence specific mechanical markers for knee osteoarthritis in the elderly. However, the study was unable to show that COMP is amenable to change in the elderly following a

  18. Preventive Effects of Eccentric Training on Acute Hamstring Muscle Injury in Professional Baseball

    Science.gov (United States)

    Seagrave, Richard A.; Perez, Luis; McQueeney, Sean; Toby, E. Bruce; Key, Vincent; Nelson, Joshua D.

    2014-01-01

    Background: Hamstring injuries are the second most common injury causing missed days in professional baseball field players. Recent studies have shown the preventive benefit of eccentric conditioning on the hamstring muscle group in injury prevention. Specifically, Nordic-type exercises have been shown to decrease the incidence of acute hamstring injuries in professional athletes. Purpose: This was a prospective study performed in coordination with a single Major League Baseball (MLB) organization (major and minor league teams) that targeted the effects of Nordic exercises on the incidence of acute hamstring injuries in the professional-level baseball player. Study Design: Prospective cohort study; Level of evidence, 2. Methods: The daily workouts of 283 professional baseball players throughout all levels of a single MLB organization were prospectively recorded. The intervention group participated in the Nordic exercise program and was compared with a randomly selected control group of professional athletes within the organization not participating in the exercise program. The incidence of hamstring injuries in both groups was compared, and the total number of days missed due to injury was compared with the 2 previous seasons. Results: There were 10 hamstring injuries that occurred during the 2012 season among the 283 professional athletes that required removal from play. There were no injuries that occurred in the intervention group (n = 65, 0.00%; P = .0381). The number needed to treat (NNT) to prevent 1 hamstring injury was 11.3. The average repetitions per week of the injured group were assessed at multiple time points (2, 4, 6, and total weeks) prior to injury. There were significantly fewer repetitions per week performed in the injured group at all time points compared with overall average repetitions per week in the noninjured group (P = .0459, .0127, .0164, and .0299, respectively). After beginning the Nordic exercise program, there were 136 total days

  19. The arrangement of muscle fibers and tendons in two muscles used for growth studies.

    OpenAIRE

    Stickland, N C

    1983-01-01

    The arrangement of muscle fibres and tendons was examined in the soleus muscle of rats from 6 to 175 days post partum. The muscle was seen to change from a simple structure, with mean fibre length of approximately 90% of complete muscle length, to a unipennate structure, with mean fibre length of only about 60% of muscle length. The dog pectineus muscle was also investigated and found to have a bipennate structure throughout postnatal growth. The arrangement of muscle fibres in both these mus...

  20. Firm anchoring between a calcium phosphate-hybridized tendon and bone for anterior cruciate ligament reconstruction in a goat model

    Energy Technology Data Exchange (ETDEWEB)

    Mutsuzaki, Hirotaka [Department of Orthopaedic Surgery, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Sakane, Masataka; Ochiai, Naoyuki [Department of Orthopaedic Surgery, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Hattori, Shinya; Kobayashi, Hisatoshi, E-mail: sakane-m@md.tsukuba.ac.j [Biomaterial Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2009-08-15

    Using an alternative soaking process improved the tendon-bone attachment for a calcium phosphate (CaP)-hybridized tendon graft. We characterized the deposited CaP on and in tendons and analyzed the histology and mechanical properties of the tendon-bone interface in anterior cruciate ligament (ACL) reconstruction in goats. The tendon grafts to be implanted were soaked ten times alternately in a Ca-containing solution and a PO{sub 4}-containing solution for 30 s each. Needlelike CaP nanocrystals including low-crystalline apatite were deposited on and between collagen fibrils from the surface to a depth of 200{mu}m inside the tendon. The structure resembles the extracellular matrix of bone. In animal experiments, the CaP-hybridized tendon directly bonded with newly formed bone at 6 weeks (n = 3), while fibrous bonding was observed in the control (n = 3). The ultimate failure load was not statistically different between the CaP (n = 7) and control (n = 7). However, in the failure mode, all the tendon-bone interfaces were intact in the CaP group, while three of seven specimens were pulled out from bone tunnels in the control. The result suggested that the strength of the tendon-bone interface in the CaP group is superior to that in the control group. Clinically, firm tendon-bone anchoring may lead to good results without the knee instability associated with the loosening of the bone-tendon junction in ACL reconstruction.

  1. Selective contribution of each hamstring muscle to anterior cruciate ligament protection and tibiofemoral joint stability in leg-extension exercise: a simulation study.

    Science.gov (United States)

    Biscarini, Andrea; Botti, Fabio Massimo; Pettorossi, Vito Enrico

    2013-09-01

    A biomechanical model was developed to simulate the selective effect of the co-contraction force provided by each hamstring muscle on the shear and compressive tibiofemoral joint reaction forces, during open kinetic-chain knee-extension exercises. This model accounts for instantaneous values of knee flexion angle [Formula: see text], angular velocity and acceleration, and for changes in magnitude, orientation, and application point of external resistance. The tibiofemoral shear force (TFSF) largely determines the tensile force on anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). Biceps femoris is the most effective hamstring muscle in decreasing the ACL-loading TFSF developed by quadriceps contractions for [Formula: see text]. In this range, the semimembranosus generates the dominant tibiofemoral compressive force, which enhances joint stability, opposes anterior/posterior tibial translations, and protects cruciate ligaments. The semitendinosus force provides the greatest decreasing gradient of ACL-loading TFSF for [Formula: see text], and the greatest increasing gradient of tibiofemoral compressive force for [Formula: see text]. However, semitendinosus efficacy is strongly limited by its small physiological section. Hamstring muscles behave as a unique muscle in enhancing the PCL-loading TFSF produced by quadriceps contractions for [Formula: see text]. The levels of hamstrings co-activation that suppress the ACL-loading TFSF considerably shift when the knee angular acceleration is changed while maintaining the same level of knee extensor torque by a concurrent adjustment in the magnitude of external resistance. The knowledge of the specific role and the optimal activation level of each hamstring muscle in ACL protection and tibiofemoral stability are fundamental for planning safe and effective rehabilitative knee-extension exercises.

  2. Kartogenin with PRP promotes the formation of fibrocartilage zone in the tendon-bone interface.

    Science.gov (United States)

    Zhou, Yiqin; Zhang, Jianying; Yang, Jinsong; Narava, Manoj; Zhao, Guangyi; Yuan, Ting; Wu, Haishan; Zheng, Nigel; Hogan, MaCalus V; Wang, James H-C

    2017-12-01

    Treatment of tendon-bone junction injuries is a challenge because tendon-bone interface often heals poorly and the fibrocartilage zone, which reduces stress concentration, at the interface is not formed. In this study, we used a compound called kartogenin (KGN) with platelet-rich plasma (PRP) to induce the formation of fibrocartilage zone in a rat tendon graft-bone tunnel model. The experimental rats received KGN-PRP or PRP injections in the tendon graft-bone tunnel interface. The control group received saline. After 4, 8 and 12 weeks, Safranin O staining of the tendon graft-bone tunnels revealed abundant proteoglycans in the KGN-PRP group indicating the formation of cartilage-like transition zone. Immunohistochemical and immuno-fluorescence staining revealed collagen types I (Col-I) and II (Col-II) in the newly formed fibrocartilage zone. Both fibrocartilage zone formation and maturation were healing time dependent. In contrast, the PRP and saline control groups had no cartilage-like tissues and minimal Col-I and Col-II staining. Some gaps were also present in the saline control group. Finally, pull-out strength in the KGN-PRP-treated group at 8 weeks was 1.4-fold higher than the PRP-treated group and 1.6-fold higher than the saline control group. These findings indicate that KGN, with PRP as a carrier, promotes the formation of fibrocartilage zone between the tendon graft and bone interface. Thus, KGN-PRP may be used as a convenient cell-free therapy in clinics to promote fibrocartilage zone formation in rotator calf repair and anterior cruciate ligament reconstruction, thereby enhancing the mechanical strength of the tendon-bone interface and hence the clinical outcome of these procedures. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Hyaluronic Acid Accelerates Tendon-to-Bone Healing After Rotator Cuff Repair.

    Science.gov (United States)

    Honda, Hirokazu; Gotoh, Masafumi; Kanazawa, Tomonoshin; Ohzono, Hiroki; Nakamura, Hidehiro; Ohta, Keisuke; Nakamura, Kei-Ichiro; Fukuda, Kanji; Teramura, Takeshi; Hashimoto, Takashi; Shichijo, Shigeki; Shiba, Naoto

    2017-12-01

    There is growing evidence that the subacromial injection of hyaluronic acid (HA) is effective for pain relief in rotator cuff tears; however, its effect on tendon-to-bone healing remains unknown. To examine the effect of HA on the chondrogenesis of mesenchymal stem cells (MSCs) in vitro and on tendon-to-bone healing in a rotator cuff repair model. Controlled laboratory study. Bilateral complete tears of the infraspinatus tendon were made in rabbits and subsequently repaired. Before closure, 1 mL HA was applied to the repaired site, and phosphate-buffered saline was used in the opposite side as a control. Biomechanical, histological, and immunohistochemical analyses were performed at 4, 8, and 12 weeks after surgery. After euthanizing each animal, the bone marrow was isolated from the femoral bone in the same rabbits. Then, MSCs were cultured in media for chondrogenic differentiation, and the chondral pellet production and cartilage-related gene expression levels in the cells were examined at various concentrations of HA. At 4 and 8 weeks after surgery, ultimate load-to-failure was significantly greater in the HA group than in the control group (45.61 ± 9.0 N vs 32.42 ± 9.4 N at 4 weeks, 90.7 ± 16.0 N vs 66.97 ± 10.0 N at 8 weeks; both P .05). Linear stiffness was not significant throughout the time point evaluation. The chondroid formation area at the tendon-bone interface stained by safranin O (control vs HA group) was 0.33% ± 0.7% versus 13.5% ± 12.3% at 4 weeks after surgery ( P repaired site stained by PicroSirius Red (control vs HA group) was 16.2 ± 10.6 versus 43.5 ± 21.3 at 4 weeks after surgery ( P .05), and 1.8% ± 4.0% versus 5.4% ± 4.2% at 12 weeks after surgery ( P > .05). Compared with the control group, HA significantly increased the volume of cartilaginous pellet produced by MSCs (0.0016 ± 0.0015 mm 3 at 0 mg/mL of HA, 0.0041 ± 0.0023 mm 3 at 1.0 mg/mL, and 0.0041 ± 0.0018 mm 3 at 4.0 mg/mL), with increased mRNA expression (relative ratio

  4. Presence of Bacteria in Spontaneous Achilles Tendon Ruptures.

    Science.gov (United States)

    Rolf, Christer G; Fu, Sai-Chuen; Hopkins, Chelsea; Luan, Ju; Ip, Margaret; Yung, Shu-Hang; Friman, Göran; Qin, Ling; Chan, Kai-Ming

    2017-07-01

    The structural pathology of Achilles tendon (AT) ruptures resembles tendinopathy, but the causes remain unknown. Recently, a number of diseases were found to be attributed to bacterial infections, resulting in low-grade inflammation and progressive matrix disturbance. The authors speculate that spontaneous AT ruptures may also be influenced by the presence of bacteria. Bacteria are present in ruptured ATs but not in healthy tendons. Cross-sectional study; Level of evidence, 3. Patients with spontaneous AT ruptures and patients undergoing anterior cruciate ligament (ACL) reconstruction were recruited for this study. During AT surgical repair, excised tendinopathic tissue was collected, and healthy tendon samples were obtained as controls from hamstring tendon grafts used in ACL reconstruction. Half of every sample was reserved for DNA extraction and the other half for histology. Polymerase chain reaction (PCR) was conducted using 16S rRNA gene universal primers, and the PCR products were sequenced for the identification of bacterial species. A histological examination was performed to compare tendinopathic changes in the case and control samples. Five of 20 AT rupture samples were positive for the presence of bacterial DNA, while none of the 23 hamstring tendon samples were positive. Sterile operating and experimental conditions and tests on samples, controlling for harvesting and processing procedures, ruled out the chance of postoperative bacterial contamination. The species identified predominantly belonged to the Staphylococcus genus. AT rupture samples exhibited histopathological features characteristic of tendinopathy, and most healthy hamstring tendon samples displayed normal tendon features. There were no apparent differences in histopathology between the bacterial DNA-positive and bacterial DNA-negative AT rupture samples. The authors have demonstrated the presence of bacterial DNA in ruptured AT samples. It may suggest the potential involvement of bacteria

  5. The Prevalence and Role of Low Lying Peroneus Brevis Muscle Belly in Patients with Peroneal Tendon Pathologies: A Potential Source for Tendon Subluxation

    OpenAIRE

    Mirmiran, Roya; Squire, Chad; Wassell, Daniel

    2015-01-01

    A low lying peroneus brevis muscle belly is a rare anomaly. There are few published studies that support presence of this anomaly as an etiology for peroneal tendon tear. However, the association between a low lying peroneus muscle belly (LLMB) and tendon subluxation is not well explored. In this retrospective study, the magnetic resonance imaging (MRI) and intraoperative findings of 50 consecutive patients undergoing a primary peroneal tendon surgery, in a five year period, were assessed. Th...

  6. Composition and structure of porcine digital flexor tendon-bone insertion tissues.

    Science.gov (United States)

    Chandrasekaran, Sandhya; Pankow, Mark; Peters, Kara; Huang, Hsiao-Ying Shadow

    2017-11-01

    Tendon-bone insertion is a functionally graded tissue, transitioning from 200 MPa tensile modulus at the tendon end to 20 GPa tensile modulus at the bone, across just a few hundred micrometers. In this study, we examine the porcine digital flexor tendon insertion tissue to provide a quantitative description of its collagen orientation and mineral concentration by using Fast Fourier Transform (FFT) based image analysis and mass spectrometry, respectively. Histological results revealed uniformity in global collagen orientation at all depths, indicative of mechanical anisotropy, although at mid-depth, the highest fiber density, least amount of dispersion, and least cellular circularity were evident. Collagen orientation distribution obtained through 2D FFT of histological imaging data from fluorescent microscopy agreed with past measurements based on polarized light microscopy. Results revealed global fiber orientation across the tendon-bone insertion to be preserved along direction of physiologic tension. Gradation in the fiber distribution orientation index across the insertion was reflective of a decrease in anisotropy from the tendon to the bone. We provided elemental maps across the fibrocartilage for its organic and inorganic constituents through time-of-flight secondary ion mass spectrometry (TOF-SIMS). The apatite intensity distribution from the tendon to bone was shown to follow a linear trend, supporting past results based on Raman microprobe analysis. The merit of this study lies in the image-based simplified approach to fiber distribution quantification and in the high spatial resolution of the compositional analysis. In conjunction with the mechanical properties of the insertion tissue, fiber, and mineral distribution results for the insertion from this may potentially be incorporated into the development of a structural constitutive approach toward computational modeling. Characterizing the properties of the native insertion tissue would provide the

  7. Specialisation of extracellular matrix for function in tendons and ligaments

    Science.gov (United States)

    Birch, Helen L.; Thorpe, Chavaunne T.; Rumian, Adam P.

    2013-01-01

    Summary Tendons and ligaments are similar structures in terms of their composition, organisation and mechanical properties. The distinction between them stems from their anatomical location; tendons form a link between muscle and bone while ligaments link bones to bones. A range of overlapping functions can be assigned to tendon and ligaments and each structure has specific mechanical properties which appear to be suited for particular in vivo function. The extracellular matrix in tendon and ligament varies in accordance with function, providing appropriate mechanical properties. The most useful framework in which to consider extracellular matrix differences therefore is that of function rather than anatomical location. In this review we discuss what is known about the relationship between functional requirements, structural properties from molecular to gross level, cellular gene expression and matrix turnover. The relevance of this information is considered by reviewing clinical aspects of tendon and ligament repair and reconstructive procedures. PMID:23885341

  8. Associations of maximal voluntary isometric hip extension torque with muscle size of hamstring and gluteus maximus and intra-abdominal pressure.

    Science.gov (United States)

    Tayashiki, Kota; Hirata, Kosuke; Ishida, Kiraku; Kanehisa, Hiroaki; Miyamoto, Naokazu

    2017-06-01

    Muscle size of the hamstring and gluteus maximus (GM) as well as intra-abdominal pressure (IAP) are considered as factors affecting the torque development during hip extension. This study examined the associations of torque development during maximal voluntary isometric hip extension with IAP and muscle size of the hamstring and GM. Anatomical cross-sectional area (ACSA) of the hamstring and thickness of GM were determined in 20 healthy young males using an ultrasonography apparatus (Experiment 1). Torque and IAP were simultaneously measured while subjects performed maximal voluntary isometric hip extension. The IAP was measured using a pressure transducer placed in the rectum and determined at the time at which the developed torque reached to the maximal. In Experiment 2, torque and IAP were measured during maximal voluntary isometric hip flexion in 18 healthy young males. The maximal hip extension torque was significantly correlated with the IAP (r = 0.504, P = 0.024), not with the ACSA of the hamstring (r = 0.307, P = 0.188) or the thickness of GM (r = 0.405, P = 0.076). The relationship was still significant even when the ACSA of the hamstring and the thickness of GM were adjusted statistically (r = 0.486, P = 0.041). The maximal hip flexion torque was not significantly correlated with the IAP (r = -0.118, P = 0.642). The current results suggest that IAP can contribute independently of the muscle size of the agonists to maximal voluntary hip extension torque.

  9. Effectiveness of passive stretching versus hold relax technique in flexibility of hamstring muscle

    Directory of Open Access Journals (Sweden)

    Gauri Shankar

    2010-10-01

    Full Text Available Aim: To compare the effectiveness of passive stretching and hold relax technique in the flexibility of hamstring muscle. Methods: A total of 80 normal healthy female subjects between age group 20-30 years referred to the department of physiotherapy, Sumandeep Vidyapeeth University, sampling method being convenient sampling. The subjects were randomly divided in two groups i.e. passive stretching group (n=40 and PNF group (n=40 and given passive stretching and proprioceptive neuromuscular facilitation technique respectively. Active knee extension range was measured before and after the intervention by goniometer. Results: t test showed a highly significant (p=0.000 increase in range of motion in PNF group. Conclusion: Proprioceptive neuromuscular facilitation technique is more effective in increasing hamstring flexibility than the passive stretching.

  10. Repeated passive stretching : Acute effect on the passive muscle moment and extensibility of short hamstrings

    NARCIS (Netherlands)

    Halbertsma, JPK; Mulder, [No Value; Goeken, LNH; Eisma, WH; Mulder, I.; Göeken, L.N.

    Objective: To examine the response of short hamstring muscles to repeated passive stretching. Design: A repeated measures design. Setting: A university laboratory for human movement analysis in a department of rehabilitation. Subjects: Students (7 men, 10 women) from the Department of Human Movement

  11. Effect of the Interposition of Calcium Phosphate Materials on Tendon-Bone Healing During Repair of Chronic Rotator Cuff Tear.

    Science.gov (United States)

    Zhao, Song; Peng, Lingjie; Xie, Guoming; Li, Dingfeng; Zhao, Jinzhong; Ning, Congqin

    2014-08-01

    The current nature of tendon-bone healing after rotator cuff (RC) repair is still the formation of granulation tissue at the tendon-bone interface rather than the formation of fibrocartilage, which is the crucial structure in native tendon insertion and can be observed after knee ligament reconstruction. The interposition of calcium phosphate materials has been found to be able to enhance tendon-bone healing in knee ligament reconstruction. However, whether the interposition of these kinds of materials can enhance tendon-bone healing or even change the current nature of tendon-bone healing after RC repair still needs to be explored. The interposition of calcium phosphate materials during RC repair would enhance tendon-bone healing or change its current nature of granulation tissue formation into a more favorable process. Controlled laboratory study. A total of 144 male Sprague-Dawley rats underwent unilateral detachment of the supraspinatus tendon, followed by delayed repair after 3 weeks. The animals were allocated into 1 of 3 groups: (1) repair alone, (2) repair with Ca5(PO4)2SiO4 (CPS) bioceramic interposition, or (3) repair with hydroxyapatite (HA) bioceramic interposition at the tendon-bone interface. Animals were sacrificed at 2, 4, or 8 weeks postoperatively, and microcomputed tomography (micro-CT) was used to quantify the new bone formation at the repair site. New fibrocartilage formation and collagen organization at the tendon-bone interface was evaluated by histomorphometric analysis. Biomechanical testing of the supraspinatus tendon-bone complex was performed. Statistical analysis was performed using 1-way analysis of variance. Significance was set at P repair, CPS bioceramic significantly increased the area of fibrocartilage at the tendon-bone interface compared with the control and HA groups. Moreover, CPS and HA bioceramics had significantly improved collagen organization. Biomechanical tests indicated that the CPS and HA groups have greater ultimate

  12. MRI of anterior cruciate ligament repair with patellar and hamstring tendon autografts

    International Nuclear Information System (INIS)

    Jansson, K.A.; Karjalainen, P.T.; Harilainen, A.; Sandelin, J.; Tallroth, K.; Soila, K.; Aronen, H.J.

    2001-01-01

    Objective. Several MRI sequences were used to evaluate the 2-year postoperative appearance of asymptomatic knee with a torn anterior cruciate ligament (ACL) reconstructed with bone-patellar tendon-bone (BTB) and semitendinosus and gracilis (STG) tendon autografts.Design and patients. Two groups with successful repair of ACL tear with BTB (n=10) or STG (n=10) autografts were imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-weighted and sagittal STIR sequences and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligamentous tissues was evaluated.Results. In all 20 cases, the ACL graft showed homogeneous, low signal intensity with periligamentous streaks of intermediate signal intensity on T2-weighted images. In 10 cases, localised areas of intermediate signal intensity were seen in the intra-articular segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in either of the two groups, but mild to moderate periligamentous enhancement was detected in 10 cases.Conclusion. The MRI appearance of ACL autograft is variable on proton density- and T1-weighted images. Periligamentous tissue showing contrast enhancement is a typical MRI finding after clinically successful ACL reconstruction. (orig.)

  13. Does eccentric training of hamstring muscles reduce acute injuries in soccer?

    Science.gov (United States)

    Nichols, Andrew W

    2013-01-01

    To investigate the effectiveness of a 10-week hamstring exercise training program in reducing the incidence and severity of new and recurrent hamstring injuries among male soccer players. Cluster-randomized (by team)controlled trial, stratified by level of play and geographic location. Sample size was calculated with 80% power to show a relative risk reduction for injury of 50% at P ≤ 0.05. Soccer community study in Denmark during the period January to December 2008. Teams in the top 5 soccer divisions (2 professional and 3 amateur)were invited to participate. The exclusion criterion for teams was that they already used eccentric hamstring exercises, and for participants was that they joined the teams after the beginning of the season. Of 116 teams, 54 were eligible and willing to be randomized and 50 were included in the analysis (942 players). Teams in both the intervention and control groups followed their normal training programs. At the beginning of the study period, the intervention teams added 27 sessions of the Nordicham string exercise (after warm-up) during the 10-week period of the mid-season break. The exercise begins with the player kneeling with the torso upright and rigid, and the feet held down to the ground by a partner. The player lowers his torso forwards toward the ground braking with his hamstring muscles until the chest reaches the ground (eccentric phase). He returns to the upright position, pushing with his hands to minimize the concentric phase load. Sessions per week and sets and repetitions per session increased to 3, 3, and 12, respectively. Team coaches supervised the sessions. A hamstring injury was defined as an acute occurrence of a “physical complaint in the region of the posterior thigh sustained during a soccer match or training, irrespective of the need for medical attention or time loss from soccer activities.” Injuries were recorded by the teams’ medical staff on standardized forms. Only first injuries during the season

  14. Coordinated collagen and muscle protein synthesis in human patella tendon and quadriceps muscle after exercise

    DEFF Research Database (Denmark)

    Miller, Benjamin F; Olesen, Jens L; Hansen, Mette

    2005-01-01

    We hypothesized that an acute bout of strenuous, non-damaging exercise would increase rates of protein synthesis of collagen in tendon and skeletal muscle but these would be less than those of muscle myofibrillar and sarcoplasmic proteins. Two groups (n = 8 and 6) of healthy young men were studied...... collagen (0.077% h(-1)), muscle collagen (0.054% h(-1)), myofibrillar protein (0.121% h(-1)), and sarcoplasmic protein (0.134% h(-1))). The rates decreased toward basal values by 72 h although rates of tendon collagen and myofibrillar protein synthesis remained elevated. There was no tissue damage...... of muscle visible on histological evaluation. Neither tissue microdialysate nor serum concentrations of IGF-I and IGF binding proteins (IGFBP-3 and IGFBP-4) or procollagen type I N-terminal propeptide changed from resting values. Thus, there is a rapid increase in collagen synthesis after strenuous exercise...

  15. Spring or string: does tendon elastic action influence wing muscle mechanics in bat flight?

    Science.gov (United States)

    Konow, Nicolai; Cheney, Jorn A; Roberts, Thomas J; Waldman, J Rhea S; Swartz, Sharon M

    2015-10-07

    Tendon springs influence locomotor movements in many terrestrial animals, but their roles in locomotion through fluids as well as in small-bodied mammals are less clear. We measured muscle, tendon and joint mechanics in an elbow extensor of a small fruit bat during ascending flight. At the end of downstroke, the tendon was stretched by elbow flexion as the wing was folded. At the end of upstroke, elastic energy was recovered via tendon recoil and extended the elbow, contributing to unfurling the wing for downstroke. Compared with a hypothetical 'string-like' system lacking series elastic compliance, the tendon spring conferred a 22.5% decrease in muscle fascicle strain magnitude. Our findings demonstrate tendon elastic action in a small flying mammal and expand our understanding of the occurrence and action of series elastic actuator mechanisms in fluid-based locomotion. © 2015 The Author(s).

  16. Effects of warm-up on hamstring muscles stiffness: Cycling vs foam rolling.

    Science.gov (United States)

    Morales-Artacho, A J; Lacourpaille, L; Guilhem, G

    2017-12-01

    This study investigated the effects of active and/or passive warm-up tasks on the hamstring muscles stiffness through elastography and passive torque measurements. On separate occasions, fourteen males randomly completed four warm-up protocols comprising Control, Cycling, Foam rolling, or Cycling plus Foam rolling (Mixed). The stiffness of the hamstring muscles was assessed through shear wave elastography, along with the passive torque-angle relationship and maximal range of motion (ROM) before, 5, and 30 minutes after each experimental condition. At 5 minutes, Cycling and Mixed decreased shear modulus (-10.3% ± 5.9% and -7.7% ± 8.4%, respectively; P≤.0003, effect size [ES]≥0.24) and passive torque (-7.17% ± 8.6% and -6.2% ± 7.5%, respectively; P≤.051, ES≥0.28), and increased ROM (+2.9% ± 2.9% and +3.2% ± 3.5%, respectively; P≤.001, ES≥0.30); 30 minutes following Mixed, shear modulus (P=.001, ES=0.21) and passive torque (P≤.068, ES≥0.2) were still slightly decreased, while ROM increased (P=.046, ES=0.24). Foam rolling induced "small" immediate short-term decreases in shear modulus (-5.4% ± 5.7% at 5 minutes; P=.05, ES=0.21), without meaningful changes in passive torque or ROM at any time point (P≥.12, ES≤0.23). These results suggest that the combined warm-up elicited no acute superior effects on muscle stiffness compared with cycling, providing evidence for the key role of active warm-up to reduce muscle stiffness. The time between warm-up and competition should be considered when optimizing the effects on muscle stiffness. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. [Bursitis with severe tendon and muscle necrosis on the lateral stifle area in cattle].

    Science.gov (United States)

    Nuss, K; Räber, M; Sydler, T; Muggli, E; Hässig, M; Guscetti, F

    2011-11-01

    In 21 animals, chronic swelling on the lateral aspect of the stifle also known as «perigonitis», «stable-syndrome» or «bursitis bicipitalis femoris» were evaluated. Ultrasonography showed increased fluid in the distal subtendinous bursa of the biceps femoris muscle and structural changes in the tendons, muscles, subcutis and fasciae. Soft tissue swelling and an irregular contour of the lateral tibial condyle were typical signs on radiographs. Macroscopic changes were found at the insertion of the biceps femoris muscle, the distal subtendinous bursa of the biceps femoris muscle, the lateral collateral ligament of the stifle, the origin of muscles on the lateral femoral condyle and the lateral tibial condyle. They mainly consisted of tendon and muscle tissue necrosis with granulation tissue. Histology revealed areas of coagulation necrosis in tendons and ligaments, in which occasionally Onchocerca spp. were seen. The severity of lesions correlated well with the clinical signs, which were associated with a poor prognosis in advanced cases.

  18. Rotator cuff muscles lose responsiveness to anabolic steroids after tendon tear and musculotendinous retraction: an experimental study in sheep.

    Science.gov (United States)

    Gerber, Christian; Meyer, Dominik C; Von Rechenberg, Brigitte; Hoppeler, Hans; Frigg, Robert; Farshad, Mazda

    2012-11-01

    Long-standing rotator cuff tendon tearing is associated with retraction, loss of work capacity, irreversible fatty infiltration, and atrophy of the rotator cuff muscles. Although continuous musculotendinous relengthening can experimentally restore muscular architecture, restoration of atrophy and fatty infiltration is hitherto impossible. Continuous relengthening with pharmacological stimulation of muscle growth using an anabolic steroid or insulin-like growth factor (IGF) can reverse atrophy and fatty infiltration as well as improve the work capacity of chronically retracted rotator cuff muscles in sheep. Controlled laboratory study. Sixteen weeks after tenotomy of the infraspinatus (ISP) tendon, atrophy and fatty infiltration had developed in the retracted ISP muscle. The musculotendinous unit was continuously relengthened in 14 sheep during 6 weeks: Four sheep were treated without pharmacological stimulation, 4 with intramuscular administration of an anabolic steroid, and 6 with IGF before final repair and rehabilitation (12 weeks). Changes were documented by intraoperative measurements of muscle work capacity, histology, and computed tomography/magnetic resonance imaging. Musculotendinous relengthening by continuous traction resulted in gains of length ranging from 0.7 cm in the IGF group to 1.3 cm in the control group. Fatty infiltration progressed in all groups, and the muscle's cross-sectional area ranged from 71% to 74% of the contralateral side at sacrifice and did not show any differences between groups in weight, volume, histological composition, or work capability of the muscle. The contralateral muscles in the anabolic steroid group, however, showed significantly higher (mean ± standard deviation) muscle work capacity of 10 ± 0.9 N·m than the contralateral muscles of the control group (6.8 ± 2.4 N·m) (P muscle fiber area as well as by an unusual gain in the animals' weight after injection of the anabolic steroid. Subcutaneous continuous

  19. Reliability of panoramic ultrasound imaging in simultaneously examining muscle size and quality of the hamstring muscles in young, healthy males and females.

    Science.gov (United States)

    Palmer, Ty B; Akehi, Kazuma; Thiele, Ryan M; Smith, Doug B; Thompson, Brennan J

    2015-03-01

    The purpose of this study was to examine the reliability of ultrasound (US) measures of cross-sectional area (CSA), muscle thickness (MT) and echo intensity (EI) of the hamstrings, with comparisons between males and females. In 20 healthy participants (10 males, 10 females), CSA, MT and EI were measured from panoramic US scans of the hamstrings on 2 separate days. The intra-class correlation coefficients and standard errors of measurement as a percentage of the mean for CSA, MT and EI ranged from 0.715 to 0.984 and from 3.145 to 12.541% in the males and from 0.724 to 0.977 and from 4.571 to 17.890% in the females, respectively. The males had greater CSAs and MTs and lower EIs than the females (p = 0.002-0.049), and significant relationships were observed between CSA and MT (r = 0.714-0.938, p ≤ 0.001-0.023). From an overall reliability standpoint, these findings suggest that panoramic US may be a reliable technique for examining muscle size and quality of the hamstrings in both males and females. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  20. Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode

    DEFF Research Database (Denmark)

    Farup, Jean; Rahbek, S K; Vendelbo, M H

    2014-01-01

    In a comparative study, we investigated the effects of maximal eccentric or concentric resistance training combined with whey protein or placebo on muscle and tendon hypertrophy. 22 subjects were allocated into either a high-leucine whey protein hydrolysate + carbohydrate group (WHD) or a carbohy......In a comparative study, we investigated the effects of maximal eccentric or concentric resistance training combined with whey protein or placebo on muscle and tendon hypertrophy. 22 subjects were allocated into either a high-leucine whey protein hydrolysate + carbohydrate group (WHD...... or contraction mode effects. In conclusion, high-leucine whey protein hydrolysate augments muscle and tendon hypertrophy following 12 weeks of resistance training – irrespective of contraction mode....

  1. Voluntary enhanced cocontraction of hamstring muscles during open kinetic chain leg extension exercise: its potential unloading effect on the anterior cruciate ligament.

    Science.gov (United States)

    Biscarini, Andrea; Benvenuti, Paolo; Botti, Fabio M; Brunetti, Antonella; Brunetti, Orazio; Pettorossi, Vito E

    2014-09-01

    A number of research studies provide evidence that hamstring cocontraction during open kinetic chain knee extension exercises enhances tibiofemoral (TF) stability and reduces the strain on the anterior cruciate ligament. To determine the possible increase in hamstring muscle coactivation caused by a voluntary cocontraction effort during open kinetic chain leg-extension exercises, and to assess whether an intentional hamstring cocontraction can completely suppress the anterior TF shear force during these exercises. Descriptive laboratory study. Knee kinematics as well as electromyographic activity in the semitendinosus (ST), semimembranosus (SM), biceps femoris (BF), and quadriceps femoris muscles were measured in 20 healthy men during isotonic leg extension exercises with resistance (R) ranging from 10% to 80% of the 1-repetition maximum (1RM). The same exercises were also performed while the participants attempted to enhance hamstring coactivation through a voluntary cocontraction effort. The data served as input parameters for a model to calculate the shear and compressive TF forces in leg extension exercises for any set of coactivation patterns of the different hamstring muscles. For R≤ 40% 1RM, the peak coactivation levels obtained with intentional cocontraction (l) were significantly higher (P hamstring muscle, maximum level l was reached at R = 30% 1RM, corresponding to 9.2%, 10.5%, and 24.5% maximum voluntary isometric contraction (MVIC) for the BF, ST, and SM, respectively, whereas the ratio l/l 0 reached its maximum at R = 20% 1RM and was approximately 2, 3, and 4 for the BF, SM, and ST, respectively. The voluntary enhanced coactivation level l obtained for R≤ 30% 1RM completely suppressed the anterior TF shear force developed by the quadriceps during the exercise. In leg extension exercises with resistance R≤ 40% 1RM, coactivation of the BF, SM, and ST can be significantly enhanced (up to 2, 3, and 4 times, respectively) by a voluntary hamstring

  2. Rectus abdominis muscle flap for repair of prepubic tendon rupture in 8 dogs.

    Science.gov (United States)

    Archipow, Wendy; Lanz, Otto I

    2011-11-01

    The clinical use and outcome of the rectus abdominis muscle flap to repair prepubic hernias were evaluated retrospectively. Medical records (2002-2007) of 8 dogs that had a rectus abdominis muscle flap to repair traumatic prepubic tendon rupture were reviewed. Only minor donor site complications were noted, including self-limiting ventral and hind-limb swelling. No long-term complications including recurrence of hernia were noted. The results of this study indicate that the rectus abdominis muscle flap is a clinically useful option for repairing prepubic tendon rupture in dogs.

  3. The epidemiology and clinical manifestations of hamstring muscle and plantar foot flexor shortening.

    Science.gov (United States)

    Joźwiak, M; Pietrzak, S; Tobjasz, F

    1997-07-01

    A population of 920 healthy children was studied with the aim of assessing the incidence of hamstring muscle and plantar foot flexor tightness, and to correlate such symptoms with gait, posture, and low back discomfort or pain. Special attention was paid to the popliteal angle and dorsal foot flexion. The borderline values for the popliteal angle in the following age groups were, boys: 3 to 5 years, 40 degrees; 6 to 15 years, 50 degrees; and 16 to 19 years, 40 degrees; girls: 3 to 5 years, 30 degrees; 6 to 14 years, 45 degrees; 15 to 19 years, 30 degrees. The borderline values for dorsal foot flexion in the following age groups were 3 to 4 years, 7 degrees; 5 to 13 years, 10 degrees; and 14 to 19 years, 5 degrees. The results obtained indicate a natural increase in hamstring tightness, particularly shortly before the pubertal growth spurt. This seems to be linked with the natural evolution of lumbar lordosis and pelvic tilt. When hamstring tightness surpassed borderline values, dorsiflexion and lumbar lordosis decreased leading to postural deformities, bending-forward deficit, discomfort when sitting, and a shambling gait.

  4. Is Soleus Muscle-Tendon-Unit Behavior Related to Ground-Force Application During the Sprint Start?

    Science.gov (United States)

    Schrödter, Erik; Brüggemann, Gert-Peter; Willwacher, Steffen

    2017-04-01

    To describe the stretch-shortening behavior of ankle plantar-flexing muscle-tendon units (MTUs) during the push-off in a sprint start. Fifty-four male (100-m personal best: 9.58-12.07 s) and 34 female (100-m personal best: 11.05-14.00 s) sprinters were analyzed using an instrumented starting block and 2-dimensional high-speed video imaging. Analysis was performed separately for front and rear legs, while accounting for block obliquities and performance levels. The results showed clear signs of a dorsiflexion in the upper ankle joint (front block 15.8° ± 7.4°, 95% CI 13.2-18.2°; rear block 8.0° ± 5.7°, 95% CI 6.4-9.7°) preceding plantar flexion. When observed in their natural block settings, the athletes' block obliquity did not significantly affect push-off characteristics. It seems that the stretch-shortening-cycle-like motion of the soleus MTU has an enhancing influence on push-off force generation. This study provides the first systematic observation of ankle-joint stretch-shortening behavior for sprinters of a wide range of performance levels. The findings highlight the importance of reactive-type training for the improvement of starting performance. Nonetheless, future studies need to resolve the independent contributions of tendinous and muscle-fascicle structures to overall MTU performance.

  5. Elastic modulus of muscle and tendon with shear wave ultrasound elastography: variations with different technical settings.

    Directory of Open Access Journals (Sweden)

    Brian Chin Wing Kot

    Full Text Available Standardization on Shear wave ultrasound elastography (SWUE technical settings will not only ensure that the results are accurate, but also detect any differences over time that may be attributed to true physiological changes. The present study evaluated the variations of elastic modulus of muscle and tendon using SWUE when different technical aspects were altered. The results of this study indicated that variations of elastic modulus of muscle and tendon were found when different transducer's pressure and region of interest (ROI's size were applied. No significant differences in elastic modulus of the rectus femoris muscle and patellar tendon were found with different acquisition times of the SWUE sonogram. The SWUE on the muscle and tendon should be performed with the lightest transducer's pressure, a shorter acquisition time for the SWUE sonogram, while measuring the mean elastic modulus regardless the ROI's size.

  6. * Fabrication and Characterization of Biphasic Silk Fibroin Scaffolds for Tendon/Ligament-to-Bone Tissue Engineering.

    Science.gov (United States)

    Font Tellado, Sònia; Bonani, Walter; Balmayor, Elizabeth R; Foehr, Peter; Motta, Antonella; Migliaresi, Claudio; van Griensven, Martijn

    2017-08-01

    Tissue engineering is an attractive strategy for tendon/ligament-to-bone interface repair. The structure and extracellular matrix composition of the interface are complex and allow for a gradual mechanical stress transfer between tendons/ligaments and bone. Thus, scaffolds mimicking the structural features of the native interface may be able to better support functional tissue regeneration. In this study, we fabricated biphasic silk fibroin scaffolds designed to mimic the gradient in collagen molecule alignment present at the interface. The scaffolds had two different pore alignments: anisotropic at the tendon/ligament side and isotropic at the bone side. Total porosity ranged from 50% to 80% and the majority of pores (80-90%) were ligament, enthesis, and cartilage markers significantly changed depending on pore alignment in each region of the scaffolds. In conclusion, the biphasic scaffolds fabricated in this study show promising features for tendon/ligament-to-bone tissue engineering.

  7. Architectural and biochemical adaptations in skeletal muscle and bone following rotator cuff injury in a rat model.

    Science.gov (United States)

    Sato, Eugene J; Killian, Megan L; Choi, Anthony J; Lin, Evie; Choo, Alexander D; Rodriguez-Soto, Ana E; Lim, Chanteak T; Thomopoulos, Stavros; Galatz, Leesa M; Ward, Samuel R

    2015-04-01

    Injury to the rotator cuff can cause irreversible changes to the structure and function of the associated muscles and bones. The temporal progression and pathomechanisms associated with these adaptations are unclear. The purpose of this study was to investigate the time course of structural muscle and osseous changes in a rat model of a massive rotator cuff tear. Supraspinatus and infraspinatus muscle architecture and biochemistry and humeral and scapular morphological parameters were measured three days, eight weeks, and sixteen weeks after dual tenotomy with and without chemical paralysis via botulinum toxin A (BTX). Muscle mass and physiological cross-sectional area increased over time in the age-matched control animals, decreased over time in the tenotomy+BTX group, and remained nearly the same in the tenotomy-alone group. Tenotomy+BTX led to increased extracellular collagen in the muscle. Changes in scapular bone morphology were observed in both experimental groups, consistent with reductions in load transmission across the joint. These data suggest that tenotomy alone interferes with normal age-related muscle growth. The addition of chemical paralysis yielded profound structural changes to the muscle and bone, potentially leading to impaired muscle function, increased muscle stiffness, and decreased bone strength. Structural musculoskeletal changes occur after tendon injury, and these changes are severely exacerbated with the addition of neuromuscular compromise. Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.

  8. Effect of age on fatty infiltration of supraspinatus muscle after experimental tendon release in rats

    Directory of Open Access Journals (Sweden)

    Farshad Mazda

    2011-12-01

    Full Text Available Abstract Background Rotator cuff tendon tear is a leading cause for atrophy, fibrosis and fatty infiltration of the rotator cuff muscles. The pathophysiology of fatty muscle infiltration is not well understood. An animal model suited to study cellular and molecular mechanisms would therefore be desirable. While a rat model has been established for chronic rotator cuff tendon pathology, sufficient and easily identifiable fatty infiltration of the muscle has not yet been shown in rats. As younger animals regenerate better, we hypothesized that the absence of a sufficient amount of fatty infiltration in previous experiments was due to the selection of young animals and that older animals would exhibit higher amounts of fatty infiltration after tendon tear. Findings The supraspinatus tendon was released using tenotomy in 3 young (6 weeks old and in 3 aged (24 months old Sprague Dawley rats (group I and II. Another 3 aged (24 months old rats underwent sham surgery and served as a control group (group III. In group I and II retraction of the musculotendinous unit was allowed for 6 weeks. All animals were sacrificed 6 weeks after surgery and the supraspinatus muscles were harvested. Each sample was examined for fatty infiltration of the muscle by histological methods and micro-CT. In histology, fat cells were counted with a 10-fold magnification in 6 fields of view twice. An adjusted measurement setup was developed for the use of micro-CT to quantify the absorption coefficient of the muscle as a reciprocal indicator for fatty infiltration, based on the established procedure for quantification of fatty infiltration on CT in humans. Tenotomy resulted in an insignificant increase of fat cells in histological sections in both, aged and young rats. Micro-CT was able to quantify small differences in the absorption coefficients of muscle samples; the absorption coefficient was 8.1% ± 11.3% lower in retracted muscles (group I and II compared with the control

  9. Three-dimensional study of pectoralis major muscle and tendon architecture.

    Science.gov (United States)

    Fung, Lillia; Wong, Brian; Ravichandiran, Kajeandra; Agur, Anne; Rindlisbacher, Tim; Elmaraghy, Amr

    2009-05-01

    A thorough understanding of the normal structural anatomy of the pectoralis major (PM) is of paramount importance in the planning of PM tendon transfers or repairs following traumatic PM tears. However, there is little consensus regarding the complex musculotendinous architecture of the PM in the anatomic or surgical literature. The purpose of this study is to model and quantify the three-dimensional architecture of the pectoralis muscle and tendon. Eleven formalin embalmed cadaveric specimens were examined: five (2M/3F) were serially dissected, digitized, and modeled in 3D using Autodesk Maya; six (4M/2F) were dissected and photographed. The PM tendon consisted of longer anterior and shorter posterior layers that were continuous inferiorly. The muscle belly consisted of an architecturally uniform clavicular head (CH) and a segmented sternal head (SH) with 6-7 segments. The most inferior SH segment in all specimens was found to fold anteriorly forming a trough that cradled the inferior aspect of the adjacent superior segment. No twisting of either the PM muscle or tendon was noted. Within the CH, the fiber bundle lengths (FBL) were found to increase from superior to inferior, whereas the mean FBLs of SH were greatest in segments 3-5 found centrally. The mean lateral pennation angle was greater in the CH (29.4 +/- 6.9 degrees ) than in the SH (20.6 +/- 2.7 degrees ). The application of these findings could form the basis of future studies to optimize surgical planning and functional recovery of repair/reconstruction procedures.

  10. Mechanical properties of human bone-tendon-bone grafts preserved by different methods and radiation sterilised

    International Nuclear Information System (INIS)

    Kaminski, A.; Gut, G.

    2008-01-01

    Full text: Patellar tendon auto and allografts are commonly used in orthopaedic surgery for reconstruction of the anterior crucial ligaments (ACL). Autografts are mainly used for primary reconstruction, while allografts are useful for revision surgery. To avoid the risk of infection diseases transmission allografts should be radiation-sterilised. As radiation-sterilisation is supposed to decrease the mechanical strength of tendon tissue, it is important to establish methods of allografts preservation and sterilisation resulting in their best quality and safety. Therefore, the purpose of the study was to compare the tensile strength of the central one third of human patellar tendon (as used for ACL reconstruction), preserved by different methods (deep fresh freezing, lyophilisation) and subsequently radiation-sterilised with doses of 0 (control), 25, 50 or 100 kGy. Bone-tendon-bone grafts were prepared from cadaveric human patella tendon with both patellar and tibial attachments. BTB grafts were preserved by deep freezing, glicerolisation or lyophilisation and radiation-sterilised with doses of 0 (control), 25, 50 or 100 kGy. To estimate mechanical properties all samples were subjected to tensile tests to failure using Instron system. Before these tests all lyophilised grafts were rehydrated. We found decrease of tensile strength of irradiated grafts compared to non-irradiated controls. Obtained results of the mechanical testing of studied grafts indicate their potential usefulness for clinical applications.(Author)

  11. The Influence of External Load on Quadriceps Muscle and Tendon Dynamics during Jumping.

    Science.gov (United States)

    Earp, Jacob E; Newton, Robert U; Cormie, Prue; Blazevich, Anthony J

    2017-11-01

    Tendons possess both viscous (rate-dependent) and elastic (rate-independent) properties that determine tendon function. During high-speed movements external loading increases both the magnitude (FT) and rate (RFDT) of tendon loading. The influence of external loading on muscle and tendon dynamics during maximal vertical jumping was explored. Ten resistance-trained men performed parallel-depth, countermovement vertical jumps with and without additional load (0%, 30%, 60%, and 90% of maximum squat lift strength), while joint kinetics and kinematics, quadriceps tendon length (LT) and patellar tendon FT and RFDT were estimated using integrated ultrasound, motion analysis and force platform data and muscle tendon modelling. Estimated FT and RFDT, but not peak LT, increased with external loading. Temporal comparisons between 0% and 90% loads revealed that FT was greater with 90% loading throughout the majority of the movement (11%-81% and 87%-95% movement duration). However, RFDT was greater with 90% load only during the early movement initiation phase (8%-15% movement duration) but was greater in the 0% load condition later in the eccentric phase (27%-38% movement duration). LT was longer during the early movement (12%-23% movement duration) but shorter in the late eccentric and early concentric phases (48%-55% movement duration) with 90% load. External loading positively influenced peak FT and RFDT but tendon strain appeared unaffected, suggesting no additive effect of external loading on patellar tendon lengthening during human jumping. Temporal analysis revealed that external loading resulted in a large initial RFDT that may have caused dynamic stiffening of the tendon and attenuated tendon strain throughout the movement. These results suggest that external loading influences tendon lengthening in both a load- and movement-dependent manner.

  12. Bioresorbable pins and interference screws for fixation of hamstring tendon grafts in anterior cruciate ligament reconstruction surgery: a randomized controlled trial.

    Science.gov (United States)

    Stengel, Dirk; Casper, Dirk; Bauwens, Kai; Ekkernkamp, Axel; Wich, Michael

    2009-09-01

    Biodegradable cross-pins have been shown to provide higher failure loads than do screws for fixation of hamstring tendons under laboratory conditions. To compare the clinical results of biodegradable pins (RigidFix) and interference screws (BioCryl) for fixation of hamstring grafts in arthroscopically assisted anterior cruciate ligament reconstruction. Study Design Randomized controlled trial; Level of evidence, 1. To test the hypothesis of a difference of 1.0 +/- 1.2 mm in anterior knee laxity between the two fixation options, 54 patients were randomly assigned to groups via a block randomization scheme and sealed envelopes. All patients underwent standardized hamstring graft reconstruction and had similar postoperative aftercare by an accelerated rehabilitation protocol. Measures assessed at baseline and after 1 and 2 years of follow-up included (1) the side-to-side difference in anterior laxity (KT-1000 arthrometer), (2) Short Form 36 physical and mental component scores, and (3) the International Knee Documentation Committee form scores. After 1 and 2 years, 26 and 21 patients in the BioCryl group and 28 and 24 patients in the RigidFix group were available for follow-up examination. No significant difference was noted in instrumented anterior translation between BioCryl and RigidFix fixation: 1 year, 0.11 (95% CI, -0.60 to 0.82; P = .7537); 2 years, 0.33 (95% CI, -0.43 to 1.08 mm; P = .3849). Also, there were no significant differences in the mean physical and mental component scores and International Knee Documentation Committee form scores and in overall complication and surgical revision rates. A pin dislocation was classified as the sole procedure-specific serious adverse event. Bioresorbable pins do not provide better clinical results than do resorbable interference screws for hamstring graft fixation in anterior cruciate ligament reconstruction surgery.

  13. Growth hormone stimulates the collagen synthesis in human tendon and skeletal muscle without affecting myofibrillar protein synthesis

    DEFF Research Database (Denmark)

    Doessing, Simon; Heinemeier, Katja M; Holm, Lars

    2010-01-01

    young individuals. rhGH administration caused an increase in serum GH, serum IGF-I, and IGF-I mRNA expression in tendon and muscle. Tendon collagen I mRNA expression and tendon collagen protein synthesis increased by 3.9-fold and 1.3-fold, respectively (P ...RNA expression and muscle collagen protein synthesis increased by 2.3-fold and 5.8-fold, respectively (P protein synthesis was unaffected by elevation of GH and IGF-I. Moderate exercise did not enhance the effects of GH manipulation. Thus, increased GH availability stimulates...... matrix collagen synthesis in skeletal muscle and tendon, but without any effect upon myofibrillar protein synthesis. The results suggest that GH is more important in strengthening the matrix tissue than for muscle cell hypertrophy in adult human musculotendinous tissue....

  14. Extensibility and stiffness of the hamstrings in patients with nonspecific low back pain.

    Science.gov (United States)

    Halbertsma, J P; Göeken, L N; Hof, A L; Groothoff, J W; Eisma, W H

    2001-02-01

    To investigate the extensibility and stiffness of the hamstrings in patients with nonspecific low back pain (LBP). An experimental design. A university laboratory for human movement analysis in a department of rehabilitation medicine. Forty subjects, a patient group (20) and a healthy control group (20). Subjects laid supine on an examination table with a lift frame, with left leg placed in a sling at the ankle. Straight leg raising, pulling force, and activity of hamstring and back muscles were recorded with electrodes. Patients indicated when they experienced tension or pain. The lift force, leg excursion, pelvic-femoral angle, first sensation of pain, and the electromyogram of the hamstrings and back muscles measured in an experimental straight-leg raising set-up. The patient group showed a significant restriction in range of motion (ROM) and extensibility of the hamstrings compared with the control group. No significant difference in hamstring muscle stiffness can be assessed between both groups. The restricted ROM and the decreased extensibility of the hamstrings in patients with nonspecific LBP is not caused by increased muscle stiffness of the hamstrings, but determined by the stretch tolerance of the patients.

  15. Gluteus medius activation during running is a risk factor for season hamstring injuries in elite footballers.

    Science.gov (United States)

    Franettovich Smith, Melinda M; Bonacci, Jason; Mendis, M Dilani; Christie, Craig; Rotstein, Andrew; Hides, Julie A

    2017-02-01

    To investigate if size and activation of the gluteal muscles is a risk factor for hamstring injuries in elite AFL players. Prospective cohort study. Twenty-six elite male footballers from a professional Australian Football League (AFL) club participated in the study. At the beginning of the season bilateral gluteus medius (GMED) and gluteus maximus (GMAX) muscle volume was measured from magnetic resonance images and electromyographic recordings of the same muscles were obtained during running. History of hamstring injury in the pre-season and incidence of hamstring injury during the season were determined from club medical data. Nine players (35%) incurred a hamstring injury during the season. History of hamstring injury was comparable between those players who incurred a season hamstring injury (2/9 players; 22%) and those who did not (3/17 players; 18%). Higher GMED muscle activity during running was a risk factor for hamstring injury (p=0.03, effect sizes 1.1-1.5). There were no statistically significant differences observed for GMED volume, GMAX volume and GMAX activation (P>0.05). This study identified higher activation of the GMED muscle during running in players who sustained a season hamstring injury. Whilst further research is required to understand the mechanism of altered muscle control, the results of this study contribute to the developing body of evidence that the lumbo-pelvic muscles may be important to consider in hamstring injury prevention and management. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  16. A functional-anatomical approach to the spine-pelvis mechanism: interaction between the biceps femoris muscle and the sacrotuberous ligament.

    Science.gov (United States)

    van Wingerden, J P; Vleeming, A; Snijders, C J; Stoeckart, R

    1993-10-01

    Summary. Sacroiliac joint dysfunction is often overlooked as a possible cause of low back pain. This is due to the use of reductionistic anatomical models. From a kinematic point of view, topographic anatomical models are generally inadequate since they categorize pelvis, lower vertebral column and legs as distinct entities. This functional-anatomical study focuses on the question whether anatomical connections between the biceps femoris muscle and the sacrotuberous ligament are kinematically useful. Forces applied to the tendon of the biceps femoris muscle, simulating biceps femoris muscle force, were shown to influence sacrotuberous ligament tension. Since sacrotuberous ligament tension influences sacroiliac joint kinematics, hamstring training could influence the sacroiliac joint and thus low back kinematics. The clinical implications with respect to 'short' hamstrings, pelvic instability and walking are discussed.

  17. Direct lentiviral-cyclooxygenase 2 application to the tendon-bone interface promotes osteointegration and enhances return of the pull-out tensile strength of the tendon graft in a rat model of biceps tenodesis.

    Directory of Open Access Journals (Sweden)

    Charles H Rundle

    Full Text Available This study sought to determine if direct application of the lentiviral (LV-cyclooxygenase 2 (COX2 vector to the tendon-bone interface would promote osteointegration of the tendon graft in a rat model of biceps tenodesis. The LV-COX2 gene transfer strategy was chosen for investigation because a similar COX2 gene transfer strategy promoted bony bridging of the fracture gap during bone repair, which involves similar histologic transitions that occur in osteointegration. Briefly, a 1.14-mm diameter tunnel was drilled in the mid-groove of the humerus of adult Fischer 344 rats. The LV-COX2 or βgal control vector was applied directly into the bone tunnel and onto the end of the tendon graft, which was then pulled into the bone tunnel. A poly-L-lactide pin was press-fitted into the tunnel as interference fixation. Animals were sacrificed at 3, 5, or 8 weeks for histology analysis of osteointegration. The LV-COX2 gene transfer strategy enhanced neo-chondrogenesis at the tendon-bone interface but with only marginal effect on de novo bone formation. The tendon-bone interface of the LV-COX2-treated tenodesis showed the well-defined tendon-to-fibrocartilage-to-bone histologic transitions that are indicative of osteointegration of the tendon graft. The LV-COX2 in vivo gene transfer strategy also significantly enhanced angiogenesis at the tendon-bone interface. To determine if the increased osteointegration was translated into an improved pull-out mechanical strength property, the pull-out tensile strength of the LV-COX2-treated tendon grafts was determined with a pull-out mechanical testing assay. The LV-COX2 strategy yielded a significant improvement in the return of the pull-out strength of the tendon graft after 8 weeks. In conclusion, the COX2-based in vivo gene transfer strategy enhanced angiogenesis, osteointegration and improved return of the pull-out strength of the tendon graft. Thus, this strategy has great potential to be developed into an

  18. Immediate effects of Graston Technique on hamstring muscle extensibility and pain intensity in patients with nonspecific low back pain.

    Science.gov (United States)

    Moon, Jong Hoon; Jung, Jin-Hwa; Won, Young Sik; Cho, Hwi-Young

    2017-02-01

    [Purpose] The purpose of this study was to analyze the effect of Graston Technique on hamstring extensibility and pain intensity in patients with nonspecific low back pain. [Subjects and Methods] Twenty-four patients with nonspecific low back pain (27-46 years of age) enrolled in the study. All participants were randomly assigned to one of two groups: Graston technique group (n=12) and a static stretching group (n=12). The Graston Technique was used on the hamstring muscles of the experimental group, while the static stretching group performed static stretching. Hamstring extensibility was recorded using the sit and reach test, and a visual analog scale was used to measure pain intensity. [Results] Both groups showed a significant improvement after intervention. In comparison to the static stretching group, the Graston technique group had significantly more improvement in hamstring extensibility. [Conclusion] The Graston Technique is a simple and effective intervention in nonspecific low back pain patients to improve hamstring extensibility and lower pain intensity, and it would be beneficial in clinical practice.

  19. Ibuprofen Differentially Affects Supraspinatus Muscle and Tendon Adaptations to Exercise in a Rat Model.

    Science.gov (United States)

    Rooney, Sarah Ilkhanipour; Baskin, Rachel; Torino, Daniel J; Vafa, Rameen P; Khandekar, Pooja S; Kuntz, Andrew F; Soslowsky, Louis J

    2016-09-01

    Previous studies have shown that ibuprofen is detrimental to tissue healing after acute injury; however, the effects of ibuprofen when combined with noninjurious exercise are debated. Administration of ibuprofen to rats undergoing a noninjurious treadmill exercise protocol will abolish the beneficial adaptations found with exercise but will have no effect on sedentary muscle and tendon properties. Controlled laboratory study. A total of 167 male Sprague-Dawley rats were divided into exercise or cage activity (sedentary) groups and acute (a single bout of exercise followed by 24 hours of rest) and chronic (2 or 8 weeks of repeated exercise) response times. Half of the rats were administered ibuprofen to investigate the effects of this drug over time when combined with different activity levels (exercise and sedentary). Supraspinatus tendons were used for mechanical testing and histologic assessment (organization, cell shape, cellularity), and supraspinatus muscles were used for morphologic (fiber cross-sectional area, centrally nucleated fibers) and fiber type analysis. Chronic intake of ibuprofen did not impair supraspinatus tendon organization or mechanical adaptations (stiffness, modulus, maximum load, maximum stress, dynamic modulus, or viscoelastic properties) to exercise. Tendon mechanical properties were not diminished and in some instances increased with ibuprofen. In contrast, total supraspinatus muscle fiber cross-sectional area decreased with ibuprofen at chronic response times, and some fiber type-specific changes were detected. Chronic administration of ibuprofen does not impair supraspinatus tendon mechanical properties in a rat model of exercise but does decrease supraspinatus muscle fiber cross-sectional area. This fundamental study adds to the growing literature on the effects of ibuprofen on musculoskeletal tissues and provides a solid foundation on which future work can build. The study findings suggest that ibuprofen does not detrimentally affect

  20. Ibuprofen Differentially Affects Supraspinatus Muscle and Tendon Adaptations to Exercise in a Rat Model

    Science.gov (United States)

    Rooney, Sarah Ilkhanipour; Baskin, Rachel; Torino, Daniel J.; Vafa, Rameen P.; Khandekar, Pooja S.; Kuntz, Andrew F.; Soslowsky, Louis J.

    2017-01-01

    Background Previous studies have shown that ibuprofen is detrimental to tissue healing following acute injury; however, the effects of ibuprofen when combined with non-injurious exercise are debated. Hypothesis We hypothesized that administration of ibuprofen to rats undergoing a non-injurious treadmill exercise protocol would abolish the beneficial adaptations found with exercise but have no effect on sedentary muscle and tendon properties. Study Design Controlled laboratory study Methods Rats were divided into exercise or cage activity (sedentary) groups and acute (a single bout of exercise followed by 24 hours of rest) and chronic (2 or 8 weeks of repeated exercise) time points. Half of the rats received ibuprofen to investigate the effects of this drug over time when combined with different activity levels (exercise and sedentary). Supraspinatus tendons were used for mechanical testing and histology (organization, cell shape, cellularity), and supraspinatus muscles were used for morphological (fiber CSA, centrally nucleated fibers) and fiber type analysis. Results Chronic intake of ibuprofen did not impair supraspinatus tendon organization or mechanical adaptations (stiffness, modulus, max load, max stress, dynamic modulus, or viscoelastic properties) to exercise. Tendon mechanical properties were not diminished and in some instances increased with ibuprofen. In contrast, total supraspinatus muscle fiber cross-sectional area decreased with ibuprofen at chronic time points, and some fiber type-specific changes were detected. Conclusions Chronic administration of ibuprofen does not impair supraspinatus tendon mechanical properties in a rat model of exercise but does decrease supraspinatus muscle fiber cross-sectional area. Clinically, these findings suggest that ibuprofen does not detrimentally affect regulation of supraspinatus tendon adaptions to exercise but does decrease muscle growth. Individuals should be advised on the risk of decreased muscle hypertrophy

  1. The effects of low-intensity pulsed ultrasound on tendon-bone healing in a transosseous-equivalent sheep rotator cuff model.

    Science.gov (United States)

    Lovric, Vedran; Ledger, Michael; Goldberg, Jerome; Harper, Wade; Bertollo, Nicky; Pelletier, Matthew H; Oliver, Rema A; Yu, Yan; Walsh, William R

    2013-02-01

    The purpose of this study was to examine the effects Low-intensity Pulsed Ultrasound has on initial tendon-bone healing in a clinically relevant extra-articular transosseous-equivalent ovine rotator cuff model. Eight skeletally mature wethers, randomly allocated to either control group (n = 4) or treatment group (n = 4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were killed 28 days post surgery to allow examination of early effects of Low-intensity Pulsed Ultrasound treatment. General improvement in histological appearance of tendon-bone integration was noted in the treatment group. Newly formed woven bone with increased osteoblast activity along the bone surface was evident. A continuum was observed between the tendon and bone in an interdigitated fashion with Sharpey's fibres noted in the treatment group. Low-intensity Pulsed Ultrasound treatment also increased bone mineral density at the tendon-bone interface (p < 0.01), while immunohistochemistry results revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05). The results of this study indicate that Low-intensity Pulsed Ultrasound may aid in the initial phase of tendon-bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface.

  2. The arrangement of muscle fibers and tendons in two muscles used for growth studies.

    Science.gov (United States)

    Stickland, N C

    1983-01-01

    The arrangement of muscle fibres and tendons was examined in the soleus muscle of rats from 6 to 175 days post partum. The muscle was seen to change from a simple structure, with mean fibre length of approximately 90% of complete muscle length, to a unipennate structure, with mean fibre length of only about 60% of muscle length. The dog pectineus muscle was also investigated and found to have a bipennate structure throughout postnatal growth. The arrangement of muscle fibres in both these muscles is such that it might be difficult (particularly in the older animals) to cut a transverse section through all the fibres contained in the muscle; some fibres might not enter the plane of section. Results on muscle fibre number in these muscles at different ages may therefore be misleading.

  3. 18F-fluorodeoxyglucose and PET/CT for noninvasive study of exercise-induced glucose uptake in rat skeletal muscle and tendon

    International Nuclear Information System (INIS)

    Skovgaard, Dorthe; Kjaer, Michael; El-Ali, Henrik; Kjaer, Andreas

    2009-01-01

    To investigate exercise-related glucose uptake in rat muscle and tendon using PET/CT and to study possible explanatory changes in gene expression for the glucose transporters (GLUT1 and GLUT4). The sciatic nerve in eight Wistar rats was subjected to electrostimulation to cause unilateral isometric contractions of the calf muscle. 18 F-Fluorodeoxyglucose was administered and a PET/CT scan of the hindlimbs was performed. SUVs were calculated in both Achilles tendons and the triceps surae muscles. To exclude a spill-over effect the tendons and muscles from an ex vivo group of eight rats were cut out and scanned separately (distance≥1 cm). Muscle contractions increased glucose uptake approximately sevenfold in muscles (p<0.001) and 36% in tendons (p<0.01). The ex vivo group confirmed the increase in glucose uptake in intact animals. GLUT1 and GLUT4 were expressed in both skeletal muscle and tendon, but no changes in mRNA levels could be detected. PET/CT can be used for studying glucose uptake in rat muscle and tendon in relation to muscle contractions; however, the increased uptake of glucose was not explained by changes in gene expression of GLUT1 and GLUT4. (orig.)

  4. Imaging of hamstring injuries: therapeutic implications

    International Nuclear Information System (INIS)

    Koulouris, George; Connell, David

    2006-01-01

    Though recent research into the diagnosis and management of hamstring disorders has resulted in early and accurate recognition of injury, hamstring strain remains the most common form of muscle injury in the active population. With prompt recognition of hamstring strain, an appropriate rest and rehabilitation routine may be devised by the sports clinician in the hope of avoiding future and possibly more debilitating injury. As such, imaging has played a pivotal role in assisting athletes, both elite and recreational, in returning to activity expeditiously. (orig.)

  5. Imaging of hamstring injuries: therapeutic implications

    Energy Technology Data Exchange (ETDEWEB)

    Koulouris, George [Thomas Jefferson University Hospital, Division of Musculoskeletal Imaging and General Diagnostic Imaging, Philadelphia, Pennsylvania (United States); Connell, David [Royal National Orthopaedic Hospital, Stanmore, Middlesex (United Kingdom)

    2006-07-15

    Though recent research into the diagnosis and management of hamstring disorders has resulted in early and accurate recognition of injury, hamstring strain remains the most common form of muscle injury in the active population. With prompt recognition of hamstring strain, an appropriate rest and rehabilitation routine may be devised by the sports clinician in the hope of avoiding future and possibly more debilitating injury. As such, imaging has played a pivotal role in assisting athletes, both elite and recreational, in returning to activity expeditiously. (orig.)

  6. Effect of unloading followed by reloading on expression of collagen and related growth factors in rat tendon and muscle

    DEFF Research Database (Denmark)

    Heinemeier, K M; Olesen, J L; Haddad, F

    2009-01-01

    Tendon tissue and the extracellular matrix of skeletal muscle respond to mechanical loading by increased collagen expression and synthesis. This response is likely a secondary effect of a mechanically induced expression of growth factors, including transforming growth factor-beta1 (TGF-beta1......) and insulin-like growth factor-I (IGF-I). It is not known whether unloading of tendon tissue can reduce the expression of collagen and collagen-inducing growth factors. Furthermore, the coordinated response of tendon and muscle tissue to disuse, followed by reloading, is unclear. Female Sprague-Dawley rats...... tissue growth factor (CTGF), myostatin, and IGF-I isoforms were measured by real-time RT-PCR in Achilles tendon and soleus muscle. The tendon mass was unchanged, while the muscle mass was reduced by 50% after HS (P

  7. Calcium-phosphate matrix with or without TGF-β3 improves tendon-bone healing after rotator cuff repair.

    Science.gov (United States)

    Kovacevic, David; Fox, Alice J; Bedi, Asheesh; Ying, Liang; Deng, Xiang-Hua; Warren, Russell F; Rodeo, Scott A

    2011-04-01

    Rotator cuff tendon heals by formation of an interposed zone of fibrovascular scar tissue. Recent studies demonstrate that transforming growth factor-beta 3 (TGF-β(3)) is associated with tissue regeneration and "scarless" healing, in contrast to scar-mediated healing that occurs with TGF-β(1). Delivery of TGF-β(3) in an injectable calcium-phosphate matrix to the healing tendon-bone interface after rotator cuff repair will result in increased attachment strength secondary to improved bone formation and collagen organization and reduced scar formation of the healing enthesis. Controlled laboratory study. Ninety-six male Sprague-Dawley rats underwent unilateral detachment of the supraspinatus tendon followed by acute repair using transosseous suture fixation. Animals were allocated into 1 of 3 groups: (1) repair alone (controls, n = 32), (2) repair augmented by application of an osteoconductive calcium-phosphate (Ca-P) matrix only (n = 32), or (3) repair augmented with Ca-P matrix + TGF-β(3) (2.75 µg) at the tendon-bone interface (n = 32). Animals were euthanized at either 2 weeks or 4 weeks postoperatively. Biomechanical testing of the supraspinatus tendon-bone complex was performed at 2 and 4 weeks (n = 8 per group). Microcomputed tomography was utilized to quantitate bone microstructure at the repair site. The healing tendon-bone interface was evaluated with histomorphometry and immunohistochemical localization of collagen types I (COLI) and III (COLIII). Statistical analysis was performed using 2-way analysis of variance with significance set at P repair site is associated with new bone formation, increased fibrocartilage, and improved collagen organization at the healing tendon-bone interface in the early postoperative period after rotator cuff repair. The addition of TGF-β(3) significantly improved strength of the repair at 4 weeks postoperatively and resulted in a more favorable COLI/COLIII ratio. The delivery of TGF-β(3) with an injectable Ca-P matrix

  8. Sport-Specific Capacity to Use Elastic Energy in the Patellar and Achilles Tendons of Elite Athletes.

    Science.gov (United States)

    Wiesinger, Hans-Peter; Rieder, Florian; Kösters, Alexander; Müller, Erich; Seynnes, Olivier R

    2017-01-01

    Introduction: During running and jumping activities, elastic energy is utilized to enhance muscle mechanical output and efficiency. However, training-induced variations in tendon spring-like properties remain under-investigated. The present work extends earlier findings on sport-specific profiles of tendon stiffness and cross-sectional area to examine whether years of distinct loading patterns are reflected by tendons' ability to store and return energy. Methods: Ultrasound scans were performed to examine the morphological features of knee extensor and plantar flexor muscle-tendon units in elite ski jumpers, distance runners, water polo players, and sedentary controls. Tendon strain energy and hysteresis were measured with combined motion capture, ultrasonography, and dynamometry. Results: Apart from the fractional muscle-to-tendon cross-sectional area ratio being lower in the knee extensors of ski jumpers (-31%) and runners (-33%) than in water polo players, no difference in the considered muscle-tendon unit morphological features was observed between groups. Similarly, no significant difference in tendon energy storage or energy return was detected between groups. In contrast, hysteresis was lower in the patellar tendon of ski jumpers (-33%) and runners (-30%) compared to controls, with a similar trend for the Achilles tendon (significant interaction effect and large effect sizes η 2 = 0.2). Normalized to body mass, the recovered strain energy of the patellar tendon was ~50% higher in ski jumpers than in water polo players and controls. For the Achilles tendon, recovered strain energy was ~40% higher in ski jumpers and runners than in controls. Discussion: Advantageous mechanical properties related to tendon spring-like function are observed in elite athletes whose sport require effective utilization of elastic energy. However, the mechanisms underpinning the better tendon capacity of some athletes to retain elastic energy could not be ascribed to intrinsic or

  9. How joint torques affect hamstring injury risk in sprinting swing-stance transition.

    Science.gov (United States)

    Sun, Yuliang; Wei, Shutao; Zhong, Yunjian; Fu, Weijie; Li, Li; Liu, Yu

    2015-02-01

    The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases.

  10. Immediate effects of Graston Technique on hamstring muscle extensibility and pain intensity in patients with nonspecific low back pain

    OpenAIRE

    Moon, Jong Hoon; Jung, Jin-Hwa; Won, Young Sik; Cho, Hwi-Young

    2017-01-01

    [Purpose] The purpose of this study was to analyze the effect of Graston Technique on hamstring extensibility and pain intensity in patients with nonspecific low back pain. [Subjects and Methods] Twenty-four patients with nonspecific low back pain (27?46 years of age) enrolled in the study. All participants were randomly assigned to one of two groups: Graston technique group (n=12) and a static stretching group (n=12). The Graston Technique was used on the hamstring muscles of the experimenta...

  11. Exploratory factor analysis for differentiating sensory and mechanical variables related to muscle-tendon unit elongation

    Directory of Open Access Journals (Sweden)

    Mauro H. Chagas

    2016-01-01

    Full Text Available ABSTRACT Background Stretching exercises are able to promote adaptations in the muscle-tendon unit (MTU, which can be tested through physiological and biomechanical variables. Identifying the key variables in MTU adaptations is crucial to improvements in training. Objective To perform an exploratory factor analysis (EFA involving the variables often used to evaluate the response of the MTU to stretching exercises. Method Maximum joint range of motion (ROMMAX, ROM at first sensation of stretching (FSTROM, peak torque (torqueMAX, passive stiffness, normalized stiffness, passive energy, and normalized energy were investigated in 36 participants during passive knee extension on an isokinetic dynamometer. Stiffness and energy values were normalized by the muscle cross-sectional area and their passive mode assured by monitoring the EMG activity. Results EFA revealed two major factors that explained 89.68% of the total variance: 53.13% was explained by the variables torqueMAX, passive stiffness, normalized stiffness, passive energy, and normalized energy, whereas the remaining 36.55% was explained by the variables ROMMAX and FSTROM. Conclusion This result supports the literature wherein two main hypotheses (mechanical and sensory theories have been suggested to describe the adaptations of the MTU to stretching exercises. Contrary to some studies, in the present investigation torqueMAX was significantly correlated with the variables of the mechanical theory rather than those of the sensory theory. Therefore, a new approach was proposed to explain the behavior of the torqueMAX during stretching exercises.

  12. Changes in skeletal muscle and tendon structure and function following genetic inactivation of myostatin in rats

    Science.gov (United States)

    Mendias, Christopher L; Lynch, Evan B; Gumucio, Jonathan P; Flood, Michael D; Rittman, Danielle S; Van Pelt, Douglas W; Roche, Stuart M; Davis, Carol S

    2015-01-01

    Myostatin is a negative regulator of skeletal muscle and tendon mass. Myostatin deficiency has been well studied in mice, but limited data are available on how myostatin regulates the structure and function of muscles and tendons of larger animals. We hypothesized that, in comparison to wild-type (MSTN+/+) rats, rats in which zinc finger nucleases were used to genetically inactivate myostatin (MSTNΔ/Δ) would exhibit an increase in muscle mass and total force production, a reduction in specific force, an accumulation of type II fibres and a decrease and stiffening of connective tissue. Overall, the muscle and tendon phenotype of myostatin-deficient rats was markedly different from that of myostatin-deficient mice, which have impaired contractility and pathological changes to fibres and their extracellular matrix. Extensor digitorum longus and soleus muscles of MSTNΔ/Δ rats demonstrated 20–33% increases in mass, 35–45% increases in fibre number, 20–57% increases in isometric force and no differences in specific force. The insulin-like growth factor-1 pathway was activated to a greater extent in MSTNΔ/Δ muscles, but no substantial differences in atrophy-related genes were observed. Tendons of MSTNΔ/Δ rats had a 20% reduction in peak strain, with no differences in mass, peak stress or stiffness. The general morphology and gene expression patterns were similar between tendons of both genotypes. This large rodent model of myostatin deficiency did not have the negative consequences to muscle fibres and extracellular matrix observed in mouse models, and suggests that the greatest impact of myostatin in the regulation of muscle mass may not be to induce atrophy directly, but rather to block hypertrophy signalling. PMID:25640143

  13. Acute effects of different dynamic exercises on hamstring strain risk factors.

    Science.gov (United States)

    Chen, Che Hsiu; Xin, Ye; Lee, Kuang Wu; Lin, Ming Ju; Lin, Jiu Jenq

    2018-01-01

    The purpose of the study was to examine the acute effects of different dynamic exercise interventions on hamstring muscle performance. Thirty-six young men with poor hamstring flexibility were randomly assigned to three intervention groups: jogging combined with dynamic open kinetic chain stretching (DS), jogging combined with dynamic closed kinetic chain stretching (lunge with eccentric hamstring windmills, LEC), and jogging only (CON) groups. Hamstring flexibility, muscle stiffness (area under the curve, AUC), joint position sense (JPS), maximal eccentric strength (ECC), and angle of peak torque (APT) were recorded before and immediately after the exercise interventions. The results showed that the hamstring flexibility increased in DS (p < 0.001); muscle stiffness decreased in DS and was lower than jogging (p < 0.001). Moreover, ECC increased in LEC and was higher than jogging and DS (p < 0.001). APT was different among 3 groups (p < 0.001). Decreased accuracy of JPS was found in DS and jogging (p < 0.001). In conclusion, the dynamic closed kinetic chain stretching (LEC) as compared to open kinetic chain stretching (DS) or jogging group, may be an effective technique to enhance muscle performance during the pre-competition warm-up routine.

  14. Contribution of hamstring fatigue to quadriceps inhibition following lumbar extension exercise.

    Science.gov (United States)

    Hart, Joseph M; Kerrigan, D Casey; Fritz, Julie M; Saliba, Ethan N; Gansneder, Bruce; Ingersoll, Christopher D

    2006-01-01

    The purpose of this study was to determine the contribution of hamstrings and quadriceps fatigue to quadriceps inhibition following lumbar extension exercise. Regression models were calculated consisting of the outcome variable: quadriceps inhibition and predictor variables: change in EMG median frequency in the quadriceps and hamstrings during lumbar fatiguing exercise. Twenty-five subjects with a history of low back pain were matched by gender, height and mass to 25 healthy controls. Subjects performed two sets of fatiguing isometric lumbar extension exercise until mild (set 1) and moderate (set 2) fatigue of the lumbar paraspinals. Quadriceps and hamstring EMG median frequency were measured while subjects performed fatiguing exercise. A burst of electrical stimuli was superimposed while subjects performed an isometric maximal quadriceps contraction to estimate quadriceps inhibition after each exercise set. Results indicate the change in hamstring median frequency explained variance in quadriceps inhibition following the exercise sets in the history of low back pain group only. Change in quadriceps median frequency explained variance in quadriceps inhibition following the first exercise set in the control group only. In conclusion, persons with a history of low back pain whose quadriceps become inhibited following lumbar paraspinal exercise may be adapting to the fatigue by using their hamstring muscles more than controls. Key PointsA neuromuscular relationship between the lumbar paraspinals and quadriceps while performing lumbar extension exercise may be influenced by hamstring muscle fatigue.QI following lumbar extension exercise in persons with a history of LBP group may involve significant contribution from the hamstring muscle group.More hamstring muscle contribution may be a necessary adaptation in the history of LBP group due to weaker and more fatigable lumbar extensors.

  15. Avulsion of subscapularis muscle tendon leading to recurrent ...

    African Journals Online (AJOL)

    The dislocation was found to be due to a complete tear of the subscapularis tendon (12 patients) and partial tears in three patients, without fracture of the lesser tuberosity in any of the patients. The repair consisted of mobilisation of the subscapularis muscle and its reinsertion into an osseous trough created in the humerus.

  16. Passive mechanical properties of gastrocnemius muscles of people with ankle contracture after stroke.

    Science.gov (United States)

    Kwah, Li Khim; Herbert, Robert D; Harvey, Lisa A; Diong, Joanna; Clarke, Jillian L; Martin, Joshua H; Clarke, Elizabeth C; Hoang, Phu D; Bilston, Lynne E; Gandevia, Simon C

    2012-07-01

    To investigate the mechanisms of contracture after stroke by comparing passive mechanical properties of gastrocnemius muscle-tendon units, muscle fascicles, and tendons in people with ankle contracture after stroke with control participants. Cross-sectional study. Laboratory in a research institution. A convenience sample of people with ankle contracture after stroke (n=20) and able-bodied control subjects (n=30). Not applicable. Stiffness and lengths of gastrocnemius muscle-tendon units, lengths of muscle fascicles, and tendons at specific tensions. At a tension of 100N, the gastrocnemius muscle-tendon unit was significantly shorter in participants with stroke (mean, 436mm) than in able-bodied control participants (mean, 444mm; difference, 8mm; 95% confidence interval [CI], 0.2-15mm; P=.04). Muscle fascicles were also shorter in the stroke group (mean, 44mm) than in the control group (mean, 50mm; difference, 6mm; 95% CI, 1-12mm; P=.03). There were no significant differences between groups in the mean stiffness or length of the muscle-tendon units and fascicles at low tension, or in the mean length of the tendons at any tension. People with ankle contracture after stroke have shorter gastrocnemius muscle-tendon units and muscle fascicles than control participants at high tension. This difference is not apparent at low tension. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  17. Rehabilitation After Hamstring-Strain Injury Emphasizing Eccentric Strengthening at Long Muscle Lengths: Results of Long-Term Follow-Up.

    Science.gov (United States)

    Tyler, Timothy F; Schmitt, Brandon M; Nicholas, Stephen J; McHugh, Malachy P

    2017-04-01

    Hamstring-strain injuries have a high recurrence rate. To determine if a protocol emphasizing eccentric strength training with the hamstrings in a lengthened position resulted in a low recurrence rate. Longitudinal cohort study. Sports-medicine physical therapy clinic. Fifty athletes with hamstring-strain injury (age 36 ± 16 y; 30 men, 20 women; 3 G1, 43 G2, 4 G3; 25 recurrent injuries) followed a 3-phase rehabilitation protocol emphasizing eccentric strengthening with the hamstrings in a lengthened position. Injury recurrence; isometric hamstring strength at 80°, 60°, 40°, and 20° knee flexion in sitting with the thigh flexed to 40° above the horizontal and the seat back at 90° to the horizontal (strength tested before return to sport). Four of the 50 athletes sustained reinjuries between 3 and 12 mo after return to sport (8% recurrence rate). The other 42 athletes had not sustained a reinjury at an average of 24 ± 12 mo after return to sport. Eight noncompliant athletes did not complete the rehabilitation and returned to sport before initiating eccentric strengthening in the lengthened state. All 4 reinjuries occurred in these noncompliant athletes. At time of return to sport, compliant athletes had full restoration of strength while noncompliant athletes had significant hamstring weakness, which was progressively worse at longer muscle lengths (compliance × side × angle P = .006; involved vs noninvolved at 20°, compliant 7% stronger, noncompliant 43% weaker). Compliance with rehabilitation emphasizing eccentric strengthening with the hamstrings in a lengthened position resulted in no reinjuries.

  18. Rationale, secondary outcome scores and 1-year follow-up of a randomised trial of platelet-rich plasma injections in acute hamstring muscle injury: the Dutch Hamstring Injection Therapy study

    NARCIS (Netherlands)

    Reurink, Gustaaf; Goudswaard, Gert Jan; Moen, Maarten H.; Weir, Adam; Verhaar, Jan A. N.; Bierma-Zeinstra, Sita M. A.; Maas, Mario; Tol, Johannes L.

    2015-01-01

    Platelet-rich plasma (PRP) injections are an experimental treatment for acute muscle injuries. We examined whether PRP injections would accelerate return to play after hamstring injury. The methods and the primary outcome measure were published in the New England Journal of Medicine (NEJM) as

  19. Reconstruction of long digital extensor tendon by cranial tibial muscle fascia graft in a dog.

    Science.gov (United States)

    Sabiza, Soroush; Khajeh, Ahmad; Naddaf, Hadi

    2016-01-01

    Tendon rupture in dogs is generally the result of a direct trauma. This report described the use of adjacent muscle autogenic fascial graft for reconstruction of distal rupture of long digital extensor tendon in a dog. A two-year-old male mix breed dog, was presented with a non-weight bearing lameness of the right hind limb and a deep rupture of lateral side of right tarsus. History taking revealed that this rupture appeared without any apparent cause, when walking around the farm, three days before. Radiography was done and no fracture was observed. Hyperextension of right tarsal joint compared to left limb was observed. Under general anesthesia, after dissections of the ruptured area, complete rupture of long digital extensor tendon was revealed. Then, we attempted to locate the edge of the tendon, however, the tendon length was shortened approximately 1 cm. Hence, a strip of 1 cm length from fascia of cranial tibial muscle was harvested to fill the defect. The graft was sutured to the two ends of tendon using locking loop pattern. Subcutaneous layers and the skin were sutured routinely. Ehmer sling bandage was applied to prevent weight bearing on the surgical region. Re-examination and phone contact with the owner eight weeks and six months postoperatively revealed a poor lameness and excellent function of the dog, respectively. It could be concluded that the fascia of adjacent muscles can be used as an autogenic graft for reconstruction of some tendon ruptures.

  20. In vitro bone formation using muscle-derived cells: a new paradigm for bone tissue engineering using polymer-bone morphogenetic protein matrices.

    Science.gov (United States)

    Lu, Helen H; Kofron, Michelle D; El-Amin, Saadiq F; Attawia, Mohammed A; Laurencin, Cato T

    2003-06-13

    Over 800,000 bone grafting procedures are performed in the United States annually, creating a demand for viable alternatives to autogenous bone, the grafting standard in osseous repair. The objective of this study was to examine the efficacy of a BMP-polymer matrix in inducing the expression of the osteoblastic phenotype and in vitro bone formation by muscle-derived cells. Specifically, we evaluated the ability of bone morphogenetic protein-7 (BMP-7), delivered from a poly(lactide-co-glycolide) (PLAGA) matrix, to induce the differentiation of cells derived from rabbit skeletal muscle into osteoblast-like cells and subsequently form mineralized tissue. Results confirmed that muscle-derived cells attached and proliferated on the PLAGA substrates. BMP-7 released from PLAGA induced the muscle-derived cells to increase bone marker expression and form mineralized cultures. These results demonstrate the efficacy of a BMP-polymer matrix in inducing the expression of the osteoblastic phenotype by muscle-derived cells and present a new paradigm for bone tissue engineering.

  1. Ultrasonography as a tool to study afferent feedback from the muscle-tendon complex during human walking

    DEFF Research Database (Denmark)

    Cronin, Neil J.; Klint, Richard af; Grey, Michael James

    2011-01-01

    In humans, one of the most common tasks in everyday life is walking, and sensory afferent feedback from peripheral receptors, particularly the muscle spindles and Golgi tendon organs (GTO), makes an important contribution to the motor control of this task. One factor that can complicate the ability...... with an examination of muscle activation to give a broader insight to neuromuscular interaction during walking. Despite the advances in understanding that these techniques have brought, there is clearly still a need for more direct methods to study both neural and mechanical parameters during human walking in order...... of these receptors to act as length, velocity and force transducers is the complex pattern of interaction between muscle and tendinous tissues, as tendon length is often considerably greater than muscle fibre length in the human lower limb. In essence, changes in muscle-tendon mechanics can influence the firing...

  2. TOB1 Deficiency Enhances the Effect of Bone Marrow-Derived Mesenchymal Stem Cells on Tendon-Bone Healing in a Rat Rotator Cuff Repair Model

    Directory of Open Access Journals (Sweden)

    Yulei Gao

    2016-01-01

    Full Text Available Background/Aims: This study investigated the effect of silencing TOB1 (Transducer of ERBB2, 1 expression in bone marrow-derived mesenchymal stem cells (MSCs on MSC-facilitated tendon-bone healing in a rat supraspinatus repair model. Methods: Rat MSCs were transduced with a recombinant lentivirus encoding short hairpin RNA (shRNA against TOB1. MSC cell proliferation was analyzed by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assays. The effect of MSCs with TOB1 deficiency on tendon-bone healing in a rat rotator cuff repair model was evaluated by biomechanical testing, histological analysis and collagen type I and II gene expression. An upstream regulator (miR-218 of TOB1 was determined in MSCs. Results: We found that knockdown of TOB1 significantly increased the proliferative activity of rat MSCs in vitro. When MSCs with TOB1 deficiency were injected into injured rat supraspinatus tendon-bone junctions, the effect on tendon-bone healing was enhanced compared to treatment with control MSCs with normal TOB1 expression, as evidenced by elevated levels of ultimate load to failure and stiffness, increased amount of fibrocartilage and augmented expression of collagen type I and type II genes. In addition, we found that the TOB1 3′ untranslated region is a direct target of miR-218. Similar to the effect of TOB1 deficiency, overexpression of miR-218 effectively promoted tendon-bone healing in rat. Conclusion: These results suggest that TOB1 may play a negative role in the effect of MSCs on tendon-bone healing, and imply that expression of TOB1 may be regulated by miR-218.

  3. How Joint Torques Affect Hamstring Injury Risk in Sprinting Swing–Stance Transition

    Science.gov (United States)

    SUN, YULIANG; WEI, SHUTAO; ZHONG, YUNJIAN; FU, WEIJIE; LI, LI; LIU, YU

    2015-01-01

    ABSTRACT Purpose The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Methods Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. Results During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. Conclusions During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases. PMID:24911288

  4. Effects of plyometric training on passive stiffness of gastrocnemii muscles and Achilles tendon.

    Science.gov (United States)

    Fouré, Alexandre; Nordez, Antoine; Cornu, Christophe

    2012-08-01

    Plyometric training is commonly used to improve athletic performance; however, it is unclear how each component of the muscle-tendon complex (MTC) is affected by this intervention. The effects of 14 weeks of plyometric training on the passive stiffness of the gastrocnemii muscles and Achilles tendon was determined simultaneously to assess possible local adaptations of elastic properties. The passive force-length relationship of the gastrocnemii MTC and elongation of the gastrocnemii muscles were determined using ultrasonography during passive cyclic stretching in 19 subjects divided into trained (n = 9) and control (n = 10) groups. An upward trend in stiffness of the gastrocnemii MTC (P = 0.09) and a significant increase in the intrinsic gastrocnemii muscle stiffness were found (P  0.05). Considering the lack of change in gastrocnemii muscle geometry, the change in the gastrocnemii muscle stiffness may be mainly due to a change in the intrinsic mechanical properties of the muscular tissues.

  5. Effects of 12-wk eccentric calf muscle training on muscle-tendon glucose uptake and SEMG in patients with chronic Achilles tendon pain

    DEFF Research Database (Denmark)

    Masood, Tahir; Kalliokoski, Kari; Magnusson, S Peter

    2014-01-01

    High-load eccentric exercises have been a key component in the conservative management of chronic Achilles tendinopathy. This study investigated the effects of a 12-wk progressive, home-based eccentric rehabilitation program on ankle plantar flexors' glucose uptake (GU) and myoelectric activity......, while the asymptomatic leg displayed higher uptake for medial gastrocnemius and flexor hallucis longus (P tendon GU than the controls (P effect on the tendon GU. Concerning SEMG, at baseline, soleus showed more relative...... within- or between-group differences. Eccentric rehabilitation was effective in decreasing subjective severity of Achilles tendinopathy. It also resulted in redistribution of relative electrical activity, but not metabolic activity, within the triceps surae muscle....

  6. Partial tear of the quadriceps tendon in a child

    International Nuclear Information System (INIS)

    Khanna, Geetika; El-Khoury, George

    2008-01-01

    We present a case of partial rupture of the quadriceps tendon in an 8-year-old girl. This is one of the youngest patients reported with a quadriceps tendon rupture, an entity seen predominantly in middle-aged people. The strength of the muscle tendon unit in a child makes tendon injuries extremely unusual as compared to apophyseal avulsions. The MR imaging findings of this unusual pediatric injury are illustrated. (orig.)

  7. Effects of acute static, ballistic, and PNF stretching exercise on the muscle and tendon tissue properties.

    Science.gov (United States)

    Konrad, A; Stafilidis, S; Tilp, M

    2017-10-01

    The purpose of this study was to investigate the influence of a single static, ballistic, or proprioceptive neuromuscular facilitation (PNF) stretching exercise on the various muscle-tendon parameters of the lower leg and to detect possible differences in the effects between the methods. Volunteers (n = 122) were randomly divided into static, ballistic, and PNF stretching groups and a control group. Before and after the 4 × 30 s stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle of the gastrocnemius medialis. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) were measured with a dynamometer. Observation of muscle-tendon junction (MTJ) displacement with ultrasound allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate stiffness. Although RoM increased (static: +4.3%, ballistic: +4.5%, PNF: +3.5%), PRT (static: -11.4%, ballistic: -11.5%, PNF: -13,7%), muscle stiffness (static: -13.1%, ballistic: -20.3%, PNF: -20.2%), and muscle-tendon stiffness (static: -11.3%, ballistic: -10.5%, PNF: -13.7%) decreased significantly in all the stretching groups. Only in the PNF stretching group, the pennation angle in the stretched position (-4.2%) and plantar flexor MVC (-4.6%) decreased significantly. Multivariate analysis showed no clinically relevant difference between the stretching groups. The increase in RoM and the decrease in PRT and muscle-tendon stiffness could be explained by more compliant muscle tissue following a single static, ballistic, or PNF stretching exercise. © 2017 The Authors Scandinavian Journal of Medicine & Science In Sports Published by John Wiley & Sons Ltd.

  8. Effect of eccentric training on the plantar flexor muscle-tendon tissue properties.

    Science.gov (United States)

    Mahieu, Nele Nathalie; McNair, Peter; Cools, Ann; D'Haen, Caroline; Vandermeulen, Katrien; Witvrouw, Erik

    2008-01-01

    It has been shown that eccentric training can be effective in the rehabilitation of patients with Achilles tendonopathy. The mechanism behind these results is not clear. However, there is evidence that tendons are able to respond to repeated forces by altering their structure and composition, and, thus, their mechanical properties change. In this regard, the objective of the present study was to investigate whether eccentric training affects the mechanical properties of the plantar flexor's muscle-tendon tissue properties. Seventy-four healthy subjects were randomized into two groups: an eccentric training group and a control group. The eccentric training group performed a 6-wk eccentric training program for the calf muscles. Before and after this period, all subjects were evaluated for dorsiflexion range of motion using universal goniometry, passive resistive torque of the plantar flexors, and stiffness of the Achilles tendon. Passive resistive torque was measured during ankle dorsiflexion on an isokinetic dynamometer. Stiffness of the Achilles tendon was assessed using a dynamometer, in combination with ultrasonography. The results of the study reveal that the dorsiflexion range of motion was significantly increased only in the eccentric training group. The eccentric heel drop program also resulted in a significant decrease of the passive resistive torque of the plantar flexors (from 16.423 +/- 0.827 to 12.651 +/- 0.617 N.m). The stiffness of the Achilles tendon did not change significantly as a result of training. These findings provide evidence that an eccentric training program results in changes to some of the mechanical properties of the plantar flexor muscles. These changes were thought to be associated with modifications to structure rather than to stretch tolerance.

  9. Comparison of erector spinae and hamstring muscle activities and lumbar motion during standing knee flexion in subjects with and without lumbar extension rotation syndrome.

    Science.gov (United States)

    Kim, Si-hyun; Kwon, Oh-yun; Park, Kyue-nam; Kim, Moon-Hwan

    2013-12-01

    The aim of this study was to compare the activity of the erector spinae (ES) and hamstring muscles and the amount and onset of lumbar motion during standing knee flexion between individuals with and without lumbar extension rotation syndrome. Sixteen subjects with lumbar extension rotation syndrome (10 males, 6 females) and 14 healthy subjects (8 males, 6 females) participated in this study. During the standing knee flexion, surface electromyography (EMG) was used to measure muscle activity, and surface EMG electrodes were attached to both the ES and hamstring (medial and lateral) muscles. A three-dimensional motion analysis system was used to measure kinematic data of the lumbar spine. An independent-t test was conducted for the statistical analysis. The group suffering from lumbar extension rotation syndrome exhibited asymmetric muscle activation of the ES and decreased hamstring activity. Additionally, the group with lumbar extension rotation syndrome showed greater and earlier lumbar extension and rotation during standing knee flexion compared to the control group. These data suggest that asymmetric ES muscle activation and a greater amount of and earlier lumbar motion in the sagittal and transverse plane during standing knee flexion may be an important factor contributing to low back pain. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... views of bone, they provide little information about muscles, tendons or joints. An MRI may be more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, rotator cuff and labrum tears ...

  11. Effectiveness of Hamstring Knee Rehabilitation Exercise Performed in Training Machine vs. Elastic Resistance Electromyography Evaluation Study

    DEFF Research Database (Denmark)

    Jakobsen, M. D.; Sundstrup, E.; Andersen, C. H.

    2014-01-01

    Objective The aim of this study was to evaluate muscle activity during hamstring rehabilitation exercises performed in training machine compared with elastic resistance. Design Six women and 13 men aged 28-67 yrs participated in a crossover study. Electromyographic (EMG) activity was recorded...... inclinometers. Results Training machines and elastic resistance showed similar high levels of muscle activity (biceps femoris and semitendinosus peak normalized EMG >80%). EMG during the concentric phase was higher than during the eccentric phase regardless of exercise and muscle. However, compared with machine.......001) during hamstring curl performed with elastic resistance (7.58 +/- 0.08) compared with hamstring curl performed in a machine (5.92 +/- 0.03). Conclusions Hamstring rehabilitation exercise performed with elastic resistance induces similar peak hamstring muscle activity but slightly lower EMG values at more...

  12. An Evidence-Based Framework for Strengthening Exercises to Prevent Hamstring Injury.

    Science.gov (United States)

    Bourne, Matthew N; Timmins, Ryan G; Opar, David A; Pizzari, Tania; Ruddy, Joshua D; Sims, Casey; Williams, Morgan D; Shield, Anthony J

    2018-02-01

    Strength training is a valuable component of hamstring strain injury prevention programmes; however, in recent years a significant body of work has emerged to suggest that the acute responses and chronic adaptations to training with different exercises are heterogeneous. Unfortunately, these research findings do not appear to have uniformly influenced clinical guidelines for exercise selection in hamstring injury prevention or rehabilitation programmes. The purpose of this review was to provide the practitioner with an evidence-base from which to prescribe strengthening exercises to mitigate the risk of hamstring injury. Several studies have established that eccentric knee flexor conditioning reduces the risk of hamstring strain injury when compliance is adequate. The benefits of this type of training are likely to be at least partly mediated by increases in biceps femoris long head fascicle length and improvements in eccentric knee flexor strength. Therefore, selecting exercises with a proven benefit on these variables should form the basis of effective injury prevention protocols. In addition, a growing body of work suggests that the patterns of hamstring muscle activation diverge significantly between different exercises. Typically, relatively higher levels of biceps femoris long head and semimembranosus activity have been observed during hip extension-oriented movements, whereas preferential semitendinosus and biceps femoris short head activation have been reported during knee flexion-oriented movements. These findings may have implications for targeting specific muscles in injury prevention programmes. An evidence-based approach to strength training for the prevention of hamstring strain injury should consider the impact of exercise selection on muscle activation, and the effect of training interventions on hamstring muscle architecture, morphology and function. Most importantly, practitioners should consider the effect of a strength training programme on

  13. Isokinetic strength testing does not predict hamstring injury in Australian Rules footballers

    OpenAIRE

    Bennell, K.; Wajswelner, H.; Lew, P.; Schall-Riaucour, A.; Leslie, S.; Plant, D.; Cirone, J.

    1998-01-01

    OBJECTIVE: To determine the relation of hamstring and quadriceps muscle strength and imbalance to hamstring injury using a prospective observational cohort study METHOD: A total of 102 senior male Australian Rules footballers aged 22.2 (3.6) years were tested at the start of a football season. Maximum voluntary concentric and eccentric torque of the hamstring and quadriceps muscles of both legs was assessed using a Kin-Com isokinetic dynamometer at angular velocities of 60 and 180 degre...

  14. Normative Quadriceps and Hamstring Muscle Strength Values for Female, Healthy, Elite Handball and Football Players.

    Science.gov (United States)

    Risberg, May A; Steffen, Kathrin; Nilstad, Agnethe; Myklebust, Grethe; Kristianslund, Eirik; Moltubakk, Marie M; Krosshaug, Tron

    2018-05-23

    Risberg, MA, Steffen, K, Nilstad, A, Myklebust, G, Kristianslund, E, Moltubakk, MM, and Krosshaug, T. Normative quadriceps and hamstring muscle strength values for female, healthy, elite handball and football players. J Strength Cond Res XX(X): 000-000, 2018-This study presents normative values for isokinetic knee extension and flexion muscle strength tests in 350 elite, female, handball (n = 150) and football (n = 200) players. Isokinetic concentric muscle strength tests at 60°·sec were recorded bilaterally using a dynamometer. Peak torque (in Newton meter [N·m]), body mass normalized peak torque (N·m·kg), and hamstring to quadriceps ratio (H:Q ratio) for dominant and nondominant legs were recorded. The female elite players were 20.9 ± 4.0 years, started playing at the elite level at the age of 18.2 ± 2.7 years, with a mean of 9.7 ± 2.2 hours of weekly in-season training. Handball players demonstrated greater quadriceps muscle strength compared with football players (11.0%) (p handball players only (p = 0.012).The H:Q ratio was significantly lower for handball players (0.58) compared with football players (0.60) (p handball and football players can be used to set rehabilitation goals for muscle strength after injury and enable comparison with uninjured legs. Significantly greater quadriceps muscle strength was found for handball players compared with football players, also when normalized to body mass.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

  15. The predictive validity of a single leg bridge test for hamstring injuries in Australian Rules Football Players.

    Science.gov (United States)

    Freckleton, Grant; Cook, Jill; Pizzari, Tania

    2014-04-01

    Hamstring muscle strain injuries (HMSI) are the greatest injury problem in kicking sports such as Australian Rules Football. Reduced hamstring muscle strength is commonly perceived to be a risk factor for hamstring injury; however, evidence is inconclusive. Testing hamstring strength with the hip and knee at functional angles and assessing endurance parameters may be more relevant for examining the risk of hamstring injury. The primary aim of this prospective study was to examine if reduced hamstring muscle strength assessed with the single leg hamstring bridge (SLHB) was a risk factor for hamstring injury. Hamstring muscle strength of 482 amateur and semielite players from 16 football clubs, mean age 20.7 (range 16-34 years), was tested during the 2011 preseason. Players were then monitored throughout the 2011 playing season for HMSI. A total of 28 hamstring injuries, 16 right and 12 left, were recorded. Players who sustained a right HMSI during the season had a significantly lower mean right SLHB score (p=0.029), were older (p=0.002) and were more likely to have sustained a past right hamstring injury (p=0.02) or right knee injury (p=0.035). For left-sided hamstring injury, the injured group was more likely to be left leg dominant (p=0.001), older athletes (p=0.002) and there was a trend towards a history of left hamstring injury (p=0.07). This study demonstrated a significant deficit in preseason SLHB scores on the right leg of players that subsequently sustained a right-sided hamstring injury. Age, previous knee injury and a history of hamstring injury were other risk factors supported in this study. Low hamstring strength appears to be a risk factor for hamstring injury; however, due to the confounding variables and low injury rate in this study, further studies are required.

  16. Intramuscular diffuse-type giant cell tumor within the hamstring muscle

    International Nuclear Information System (INIS)

    Yoshida, Tatsuya; Sakamoto, Akio; Tanaka, Kazuhiro; Iwamoto, Yukihide; Oda, Yoshinao; Izumi, Teiyu; Tsuneyoshi, Masazumi

    2007-01-01

    Diffuse-type giant cell tumor (D-TGCT) is known as a synonym for pigmented villonodular synovitis (PVS), a condition usually found in the large joints. We report an extremely rare case of D-TGCT which was located within the hamstring muscle. The lesion was an incidental finding in a 62-year-old man who underwent positron emission tomography (PET) as part of a staging evaluation for gastric cancer. The lesion was resected. There has been neither metastasis nor recurrence during the 6-month period since resection. This case demonstrates that PVS/D-TGCT may have a high SUV on PET imaging, and for this reason PET may be useful for detecting both the tumor and any recurrence. (orig.)

  17. Magnetotherapy: The quest for tendon regeneration.

    Science.gov (United States)

    Pesqueira, Tamagno; Costa-Almeida, Raquel; Gomes, Manuela E

    2018-05-09

    Tendons are mechanosensitive tissues that connect and transmit the forces generated by muscles to bones by allowing the conversion of mechanical input into biochemical signals. These physical forces perform the fundamental work of preserving tendon homeostasis assuring body movements. However, overloading causes tissue injuries, which leads us to the field of tendon regeneration. Recently published reviews have broadly shown the use of biomaterials and different strategies to attain tendon regeneration. In this review, our focus is the use of magnetic fields as an alternative therapy, which has demonstrated clinical relevance in tendon medicine because of their ability to modulate cell fate. Yet the underlying cellular and molecular mechanisms still need to be elucidated. While providing a brief outlook about specific signalling pathways and intracellular messengers as framework in play by tendon cells, application of magnetic fields as a subcategory of physical forces is explored, opening up a compelling avenue to enhance tendon regeneration. We outline here useful insights on the effects of magnetic fields both at in vitro and in vivo levels, particularly on the expression of tendon genes and inflammatory cytokines, ultimately involved in tendon regeneration. Subsequently, the potential of using magnetically responsive biomaterials in tendon tissue engineering is highlighted and future directions in magnetotherapy are discussed. © 2018 Wiley Periodicals, Inc.

  18. The effects of static stretch duration on the flexibility of hamstring ...

    African Journals Online (AJOL)

    The effects of static stretch duration on the flexibility of hamstring muscles. NA Odunaiya, TK Hamzat, OF Ajayi. Abstract. The effects of duration of a static stretching protocol (Intervention) on hamstrings tightness were evaluated. Sixty purposively sampled subjects with unilateral hamstring tightness that had no history of low ...

  19. Noninvasive Cu-64-ATSM and PET/CT Assessment of Hypoxia in Rat Skeletal Muscles and Tendons During Muscle Contractions

    DEFF Research Database (Denmark)

    Skovgaard, D.; Kjaer, M.; Madsen, J.

    2009-01-01

    the first PET/CT scan. Standardized uptake values (SUVs) were calculated for the Achilles tendons and triceps surae muscles and were correlated to gene expression of HIF1 alpha and CAIII using real-time polymerase chain reaction. Results: Immediately after the contractions, uptake of Cu-64-ATSM......The purpose of the present study was to investigate exercise-related changes in oxygenation in rat skeletal muscles and tendons noninvasively with PET/CT and the hypoxia-selective tracer Cu-64-diacetyl bis(N-4-methylthiosemicarbazone) (ATSM) and to quantitatively study concomitant changes in gene...... expression of 2 hypoxia-related genes, hypoxia-inducible factor 1 alpha (HIF1 alpha) and carbonic anhydrase III (CAIII). Methods: Two groups of Wistar rats performed 1-leg contractions of the calf muscle by electrostimulation of the sciatic nerve. After 10 min of muscle contractions, Cu-64-ATSM was injected...

  20. Noninvasive 64Cu-ATSM and PET/CT Assessment of Hypoxia in Rat Skeletal Muscles and Tendons During Muscle Contractions

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Kjaer, Michael; Madsen, Jacob

    2009-01-01

    the first PET/CT scan. Standardized uptake values (SUVs) were calculated for the Achilles tendons and triceps surae muscles and were correlated to gene expression of HIF1alpha and CAIII using real-time polymerase chain reaction. RESULTS: Immediately after the contractions, uptake of (64)Cu......The purpose of the present study was to investigate exercise-related changes in oxygenation in rat skeletal muscles and tendons noninvasively with PET/CT and the hypoxia-selective tracer (64)Cu-diacetyl bis(N(4)-methylthiosemicarbazone) (ATSM) and to quantitatively study concomitant changes in gene...... expression of 2 hypoxia-related genes, hypoxia-inducible factor 1alpha (HIF1alpha) and carbonic anhydrase III (CAIII). METHODS: Two groups of Wistar rats performed 1-leg contractions of the calf muscle by electrostimulation of the sciatic nerve. After 10 min of muscle contractions, (64)Cu-ATSM was injected...

  1. Advanced age diminishes tendon-to-bone healing in a rat model of rotator cuff repair.

    Science.gov (United States)

    Plate, Johannes F; Brown, Philip J; Walters, Jordan; Clark, John A; Smith, Thomas L; Freehill, Michael T; Tuohy, Christopher J; Stitzel, Joel D; Mannava, Sandeep

    2014-04-01

    Advanced patient age is associated with recurrent tearing and failure of rotator cuff repairs clinically; however, basic science studies have not evaluated the influence of aging on tendon-to-bone healing after rotator cuff repair in an animal model. Hypothesis/ This study examined the effect of aging on tendon-to-bone healing in an established rat model of rotator cuff repair using the aged animal colony from the National Institute on Aging of the National Institutes of Health. The authors hypothesized that normal aging decreases biomechanical strength and histologic organization at the tendon-to-bone junction after acute repair. Controlled laboratory study. In 56 F344xBN rats, 28 old and 28 young (24 and 8 months of age, respectively), the supraspinatus tendon was transected and repaired. At 2 or 8 weeks after surgery, shoulder specimens underwent biomechanical testing to compare load-to-failure and load-relaxation response between age groups. Histologic sections of the tendon-to-bone interface were assessed with hematoxylin and eosin staining, and collagen fiber organization was assessed by semiquantitative analysis of picrosirius red birefringence under polarized light. Peak failure load was similar between young and old animals at 2 weeks after repair (31% vs 26% of age-matched uninjured controls, respectively; P > .05) but significantly higher in young animals compared with old animals 8 weeks after repair (86% vs 65% of age-matched uninjured controls, respectively; P repair, fibroblasts appeared more organized and uniformly aligned in young animals on hematoxylin and eosin slides compared with old animals. Collagen birefringence analysis of the tendon-to-bone junction demonstrated that young animals had increased collagen fiber organization and similar histologic structure compared with age-matched controls (53.7 ± 2.4 gray scales; P > .05). In contrast, old animals had decreased collagen fiber organization and altered structure compared with age

  2. Enhanced Tendon-to-Bone Healing of Chronic Rotator Cuff Tears by Bone Marrow Aspirate Concentrate in a Rabbit Model

    Science.gov (United States)

    Liu, Xiao Ning; Yang, Cheol-Jung; Kim, Ji Eui; Du, Zhen Wu; Ren, Ming; Zhang, Wei; Zhao, Hong Yu; Kim, Kyung Ok

    2018-01-01

    Background To evaluate the influence of bone marrow aspirate concentrate (BMAC) on tendon-to-bone healing in a rabbit rotator cuff model and to characterize the composition of growth factors in BMAC. Methods In this in vivo study, 40 rabbits were allocated into five groups: control (C), repair + saline (RS), repair + platelet-rich plasma (PRP; RP), repair + BMAC (RB) and repair + PRP + BMAC (RPB). A tear model was created by supraspinatus tendon transection at the footprint. Six weeks after transection, the torn tendon was repaired along with BMAC or PRP administration. Six weeks after repair, shoulder samples were harvested for biomechanical and histological testing. Ten rabbits were used for processing PRP and BMAC, followed by analysis of blood cell composition and the levels of growth factors in vitro. Results The ultimate load-to-failure was significantly higher in RPB group compared to RS group (p = 0.025). BMAC-treated groups showed higher values of biomechanical properties than RS group. The histology of BMAC-treated samples showed better collagen fiber continuity and orientation than RS group. BMAC contained significantly higher levels of the several growth factors than PRP. Conclusions Locally administered BMAC enhanced tendon-to-bone healing and has potential for clinical applications. PMID:29564054

  3. Flexible bipolar nanofibrous membranes for improving gradient microstructure in tendon-to-bone healing.

    Science.gov (United States)

    Li, Xiaoxi; Cheng, Ruoyu; Sun, Zhiyong; Su, Wei; Pan, Guoqing; Zhao, Song; Zhao, Jinzhong; Cui, Wenguo

    2017-10-01

    Enthesis is a specialized tissue interface between the tendon and bone. Enthesis structure is very complex because of gradient changes in its composition and structure. There is currently no strategy to create a suitable environment and to regenerate the gradual-changing enthesis because of the modular complexities between two tissue types. Herein, a dual-layer organic/inorganic flexible bipolar fibrous membrane (BFM) was successfully fabricated by electrospinning to generate biomimetic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. The growth of the in situ apatite nanoparticle layer was induced on the nano hydroxyapatite-poly-l-lactic acid (nHA-PLLA) fibrous layer in simulated body solution, and the poly-l-lactic acid (PLLA) fibrous layer retained its original properties to induce tendon regeneration. The in vivo results showed that BFM significantly increased the area of glycosaminoglycan staining at the tendon-bone interface and improved collagen organization when compared to the simplex fibrous membrane (SFM) of PLLA. Implanting the bipolar membrane also induced bone formation and fibrillogenesis as assessed by micro-CT and histological analysis. Biomechanical testing showed that the BFM group had a greater ultimate load-to-failure and stiffness than the SFM group at 12weeks after surgery. Therefore, this flexible bipolar nanofibrous membrane improves the healing and regeneration process of the enthesis in rotator cuff repair. In this study, we generated a biomimetic dual-layer organic/inorganic flexible bipolar fibrous membrane by sequential electrospinning and in situ biomineralization, producing integrated bipolar fibrous membranes of PLLA fibrous membrane as the upper layer and nHA-PLLA fibrous membrane as the lower layer to mimic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. Flexible bipolar nanofibrous membranes could be easily fabricated

  4. [Foster Modification of Full Tendon Transposition of Vertical Rectus Muscles for Sixth Nerve Palsy].

    Science.gov (United States)

    Heede, Santa

    2018-04-11

    Since 1907 a variety of muscle transposition procedures for the treatment of abducens nerve palsy has been established internationally. Full tendon transposition of the vertical rectus muscle was initially described by O'Connor 1935 and then augmented by Foster 1997 with addition of posterior fixation sutures on the vertical rectus muscle. Full tendon transposition augmented by Foster belongs to the group of the most powerful surgical techniques to improve the abduction. Purpose of this study was to evaluate the results of full tendon vertical rectus transposition augmented with lateral fixation suture for patients with abducens nerve palsy. Full tendon transpositions of vertical rectus muscles augmented with posterior fixation suture was performed in 2014 on five patients with abducens nerve palsy. Two of the patients received Botox injections in the medial rectus muscle: one of them three months after the surgery and another during the surgery. One of the patients had a combined surgery of the horizontal muscles one year before. On three of the patients, who received a pure transposition surgery, the preoperative deviation at the distance (mean: + 56.6 pd; range: + 40 to + 80 pd) was reduced by a mean of 39.6 pd (range 34 to 50 pd), the abduction was improved by a mean of 3 mm (range 2 to 4 mm). The other two patients, who received besides the transposition procedure additional surgeries of the horizontal muscles, the preoperative deviation at the distance (+ 25 and + 126 pd respectively) was reduced by 20 and 81 pd respectively. The abduction was improved by 4 and 8 mm respectively. After surgery two patients developed a vertical deviation with a maximum of 4 pd. None of the patients had complications or signs of anterior segment ischemia. The elevation and/or depression was only marginally affected. There was no diplopia in up- or downgaze. Full tendon transposition of vertical rectus muscles, augmented with lateral posterior fixation suture is

  5. Quadriceps Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    Science.gov (United States)

    Hurley, Eoghan T; Calvo-Gurry, Manuel; Withers, Dan; Farrington, Shane K; Moran, Ray; Moran, Cathal J

    2018-05-01

    To systematically review the current evidence to ascertain whether quadriceps tendon autograft (QT) is a viable option in anterior cruciate ligament reconstruction. A literature review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Cohort studies comparing QT with bone-patellar tendon-bone autograft (BPTB) or hamstring tendon autograft (HT) were included. Clinical outcomes were compared, with all statistical analyses performed using IBM SPSS Statistics for Windows, version 22.0, with P < .05 being considered statistically significant. We identified 15 clinical trials with 1,910 patients. In all included studies, QT resulted in lower rates of anterior knee pain than BPTB. There was no difference in the rate of graft rupture between QT and BPTB or HT in any of the studies reporting this. One study found that QT resulted in greater knee stability than BPTB, and another study found increased stability compared with HT. One study found that QT resulted in improved functional outcomes compared with BPTB, and another found improved outcomes compared with HT, but one study found worse outcomes compared with BPTB. Current literature suggests QT is a viable option in anterior cruciate ligament reconstruction, with published literature showing comparable knee stability, functional outcomes, donor-site morbidity, and rerupture rates compared with BPTB and HT. Level III, systematic review of Level I, II, and III studies. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. Changes in Indirect Markers of Muscle Damage and Tendons After Daily Drop Jumping Exercise with Rapid Load Increase

    Directory of Open Access Journals (Sweden)

    Vidas Paleckis, Mantas Mickevičius, Audrius Snieckus, Vytautas Streckis, Mati Pääsuke, Saulius Rutkauskas, Rasa Steponavičiūtė, Albertas Skurvydas, Sigitas Kamandulis

    2015-12-01

    Full Text Available The aim of this study was to assess changes in indirect markers of muscle damage and type I collagen degradation, as well as, patellar and Achilles tendon morphological differences during nine daily drop-jumps sessions with constant load alternated with rapid increases in load to test the hypothesis that frequent drop-jump training results in negative muscular and tendon adaptation. Young men (n = 9 performed daily drop jump workouts with progression every 3 days in terms of number of jumps, platform height and squat amplitude. Voluntary and electrically evoked knee extensor torque, muscle soreness, blood plasma creatine kinase (CK activity and carboxyterminal cross-linked telopeptide (ICTP, patellar and Achilles tendon thickness and cross-sectional area (CSA were assessed at different time points during the training period and again on days 1, 3, 10 and 17 after the training. The findings were as follows: (1 steady decline in maximal muscle strength with major recovery within 24 hours after the first six daily training sessions; (2 larger decline in electrically induced muscle torque and prolonged recovery during last three training sessions; (3 increase in patellar and Achilles tendons CSA without change in thickness towards the end of training period; (4 increase in jump height but not in muscle strength after whole training period. Our findings suggest that frequent drop-jump sessions with constant load alternated with rapid increases in load do not induce severe muscle damage or major changes in tendons, nonetheless, this type of loading is not advisable for muscle strength improvement.

  7. Recruitment of faster motor units is associated with greater rates of fascicle strain and rapid changes in muscle force during locomotion.

    Science.gov (United States)

    Lee, Sabrina S M; de Boef Miara, Maria; Arnold, Allison S; Biewener, Andrew A; Wakeling, James M

    2013-01-15

    Animals modulate the power output needed for different locomotor tasks by changing muscle forces and fascicle strain rates. To generate the necessary forces, appropriate motor units must be recruited. Faster motor units have faster activation-deactivation rates than slower motor units, and they contract at higher strain rates; therefore, recruitment of faster motor units may be advantageous for tasks that involve rapid movements or high rates of work. This study identified motor unit recruitment patterns in the gastrocnemii muscles of goats and examined whether faster motor units are recruited when locomotor speed is increased. The study also examined whether locomotor tasks that elicit faster (or slower) motor units are associated with increased (or decreased) in vivo tendon forces, force rise and relaxation rates, fascicle strains and/or strain rates. Electromyography (EMG), sonomicrometry and muscle-tendon force data were collected from the lateral and medial gastrocnemius muscles of goats during level walking, trotting and galloping and during inclined walking and trotting. EMG signals were analyzed using wavelet and principal component analyses to quantify changes in the EMG frequency spectra across the different locomotor conditions. Fascicle strain and strain rate were calculated from the sonomicrometric data, and force rise and relaxation rates were determined from the tendon force data. The results of this study showed that faster motor units were recruited as goats increased their locomotor speeds from level walking to galloping. Slow inclined walking elicited EMG intensities similar to those of fast level galloping but different EMG frequency spectra, indicating that recruitment of the different motor unit types depended, in part, on characteristics of the task. For the locomotor tasks and muscles analyzed here, recruitment patterns were generally associated with in vivo fascicle strain rates, EMG intensity and tendon force. Together, these data provide

  8. Recruitment of faster motor units is associated with greater rates of fascicle strain and rapid changes in muscle force during locomotion

    Science.gov (United States)

    Lee, Sabrina S. M.; de Boef Miara, Maria; Arnold, Allison S.; Biewener, Andrew A.; Wakeling, James M.

    2013-01-01

    SUMMARY Animals modulate the power output needed for different locomotor tasks by changing muscle forces and fascicle strain rates. To generate the necessary forces, appropriate motor units must be recruited. Faster motor units have faster activation–deactivation rates than slower motor units, and they contract at higher strain rates; therefore, recruitment of faster motor units may be advantageous for tasks that involve rapid movements or high rates of work. This study identified motor unit recruitment patterns in the gastrocnemii muscles of goats and examined whether faster motor units are recruited when locomotor speed is increased. The study also examined whether locomotor tasks that elicit faster (or slower) motor units are associated with increased (or decreased) in vivo tendon forces, force rise and relaxation rates, fascicle strains and/or strain rates. Electromyography (EMG), sonomicrometry and muscle-tendon force data were collected from the lateral and medial gastrocnemius muscles of goats during level walking, trotting and galloping and during inclined walking and trotting. EMG signals were analyzed using wavelet and principal component analyses to quantify changes in the EMG frequency spectra across the different locomotor conditions. Fascicle strain and strain rate were calculated from the sonomicrometric data, and force rise and relaxation rates were determined from the tendon force data. The results of this study showed that faster motor units were recruited as goats increased their locomotor speeds from level walking to galloping. Slow inclined walking elicited EMG intensities similar to those of fast level galloping but different EMG frequency spectra, indicating that recruitment of the different motor unit types depended, in part, on characteristics of the task. For the locomotor tasks and muscles analyzed here, recruitment patterns were generally associated with in vivo fascicle strain rates, EMG intensity and tendon force. Together, these

  9. Hamstring muscle strains in professional football players: a 10-year review.

    Science.gov (United States)

    Elliott, Marcus C C W; Zarins, Bertram; Powell, John W; Kenyon, Charles D

    2011-04-01

    Investigations into hamstring strain injuries at the elite level exist in sports such as Australian Rules football, rugby, and soccer, but no large-scale study exists on the incidence and circumstances surrounding these injuries in the National Football League (NFL). Injury rates will vary between different player positions, times in the season, and across different playing situations. Descriptive epidemiology study. Between 1989 and 1998, injury data were prospectively collected by athletic trainers for every NFL team and recorded in the NFL's Injury Surveillance System. Data collected included team, date of injury, activity the player was engaged in at the time of injury, injury severity, position played, mechanism of injury, and history of previous injury. Injury rates were reported in injuries per athlete-exposure (A-E). An athlete-exposure was defined as 1 athlete participating in either 1 practice or 1 game. Over the 10-year study period 1716 hamstring strains were reported for an injury rate (IR) of 0.77 per 1000 A-E. More than half (51.3%) of hamstring strains occurred during the 7-week preseason. The preseason practice IR was significantly elevated compared with the regular-season practice IR (0.82/1000 A-E and 0.18/1000 A-E, respectively). The most commonly injured positions were the defensive secondary, accounting for 23.1% of the injuries; the wide receivers, accounting for 20.8%; and special teams, constituting 13.0% of the injuries in the study. Hamstring strains are a considerable cause of disability in football, with the majority of injuries occurring during the short preseason. In particular, the speed position players, such as the wide receivers and defensive secondary, as well as players on the special teams units, are at elevated risk for injury. These positions and situations with a higher risk of injury provide foci for preventative interventions.

  10. Tendon and skeletal muscle matrix gene expression and functional responses to immobilisation and rehabilitation in young males

    DEFF Research Database (Denmark)

    Boesen, Anders Ploug; Dideriksen, Kasper; Couppé, Christian

    2013-01-01

    weeks followed by six weeks of strength training. Cross sectional area (CSA), maximal muscle strength (MVC) and biomechanical properties of m.quadriceps and patellar tendon were determined. Muscle and tendon biopsies were analysed for mRNA of collagen (COL-1A1/3A1), insulin-like growth factors (IGF-1Ea...... in both groups. Likewise, both groups increased in IGF-1Ea/Ec and COL-1A1/3A1 expression in muscle during re-training after immobilisation compared to baseline, and the rise was more pronounced when subjects recieved GH. The tendon CSA did not change during immobilisation, but increased in both groups...... during six weeks of rehabilitation (~14%). A decline in tendon stiffness after immobilisation was observed only in Plc, and an increase during six weeks rehabilitation was observed only in GH. IGF-1Ea and COL-1A1/3A1 mRNA increased with immobilisation in the GH group only, and LOX mRNA was after...

  11. A simple model to estimate plantarflexor muscle-tendon mechanics and energetics during walking with elastic ankle exoskeletons

    Science.gov (United States)

    Sawicki, Gregory S.; Khan, Nabil S.

    2016-01-01

    Goal A recent experiment demonstrated that when humans wear unpowered elastic ankle exoskeletons with intermediate spring stiffness they can reduce their metabolic energy cost to walk by ~7%. Springs that are too compliant or too stiff have little benefit. The purpose of this study was to use modeling and simulation to explore the muscle-level mechanisms for the ‘sweet-spot’ in stiffness during exoskeleton assisted walking. Methods We developed a simple lumped, uniarticular musculoskeletal model of the plantarflexors operating in parallel with an elastic ‘exo-tendon’. Using an inverse approach with constrained kinematics and kinetics, we rapidly simulated human walking over a range of exoskeleton stiffness values and examined the underlying neuromechanics and energetics of the biological plantarflexors. Results Stiffer ankle exoskeleton springs resulted in larger decreases in plantarflexor muscle forces, activations and metabolic energy consumption. However, in the process of unloading the compliant biological muscle-tendon unit (MTU), the muscle fascicles (CE) experienced larger excursions that negatively impacted series elastic element (SEE) recoil that is characteristic of a tuned ‘catapult mechanism’. Conclusion The combination of disrupted muscle-tendon dynamics and the need to produce compensatory forces/moments to maintain overall net ankle moment invariance could explain the ‘sweet spot’ in metabolic performance at intermediate ankle exoskeleton stiffness. Future work will aim to provide experimental evidence to support the model predictions presented here using ultrasound imaging of muscle-level dynamics during walking with elastic ankle exoskeletons. Significance Engineers must account for the muscle-level effects of exoskeleton designs in order to achieve maximal performance objectives. PMID:26485350

  12. Patellar Sleeve Fracture With Ossification of the Patellar Tendon.

    Science.gov (United States)

    Damrow, Derek S; Van Valin, Scott E

    2017-03-01

    Patellar sleeve fractures make up greater than 50% of all patellar fractures. They are essentially only seen in the pediatric population because of the thick periosteum and the distal patellar pole apophysis in this group. These fractures can lead to complications if not treated appropriately and in a timely fashion. Complications of missed or untreated patellar sleeve fractures include patella alta, anterior knee pain, and quadriceps atrophy. These can all result in severe limitations in activity. The authors describe a case of a 16-year-old boy who sustained a patellar sleeve fracture 3 years prior to presentation. On presentation, he had patella alta, diminished strength, 5° of extensor lag, and radiographs that revealed bone formation along the patellar tendon. Despite this, he was able to maintain a high level of activity. This case report explores how the patient could have maintained a high level of activity despite having a patellar sleeve fracture. Also, because of the delayed presentation, the patella was ossified and the quadriceps was retracted, which led to a novel approach to reconstructing his distal extensor mechanism. This approach included a V-Y advancement of the quadriceps tendon and patellar tendon reconstruction using the patient's hamstring tendon (semitendinosus). This technique, combined with physical therapy postoperatively, resulted in his return to varsity high school soccer. To the best of the authors' knowledge, this technique has not been reported for this rare condition. [Orthopedics. 2017; 40(2):e357-e359.]. Copyright 2016, SLACK Incorporated.

  13. Differences between two subgroups of low back pain patients in lumbopelvic rotation and symmetry in the erector spinae and hamstring muscles during trunk flexion when standing.

    Science.gov (United States)

    Kim, Min-hee; Yoo, Won-gyu; Choi, Bo-ram

    2013-04-01

    The present study was performed to examine lumbopelvic rotation and to identify asymmetry of the erector spinae and hamstring muscles in people with and without low back pain (LBP). The control group included 16 healthy subjects, the lumbar-flexion-rotation syndrome LBP group included 17 subjects, and the lumbar-extension-rotation syndrome LBP group included 14 subjects. Kinematic parameters were recorded using a 3D motion-capture system, and electromyography parameters were measured using a Noraxon TeleMyo 2400T. The two LBP subgroups showed significantly more lumbopelvic rotation during trunk flexion in standing than did the control group. The muscle activity and flexion-relaxation ratio asymmetries of the erector spinae muscles in the lumbar-flexion-rotation syndrome LBP group were significantly greater than those in the control group, and the muscle activity and flexion-relaxation ratio asymmetry of the hamstring muscles in the lumbar-extension-rotation syndrome LBP group were significantly greater than those in the control group. Imbalance or asymmetry of passive tissue could lead to asymmetry of muscular activation. Muscle imbalance can cause asymmetrical alignment or movements such as unexpected rotation. The results showed a greater increase in lumbopelvic rotation during trunk flexion in standing among the lumbar-flexion-rotation syndrome and lumbar-extension-rotation syndrome LBP groups compared with the control group. The differences between the two LBP subgroups may be a result of imbalance and asymmetry in erector spinae and hamstring muscle properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Quadriceps Tendon Rupture and Contralateral Patella Tendon Avulsion Post Primary Bilateral Total Knee Arthroplasty: A Case Report

    Directory of Open Access Journals (Sweden)

    Gaurav Sharma

    2016-07-01

    Full Text Available Background: Extensor mechanism failure secondary to knee replacement could be due to tibial tubercle avulsion, Patellar tendon rupture, patellar fracture or quadriceps tendon rupture. An incidence of Patella tendon rupture of 0.17% and Quadriceps tendon rupture of around 0.1% has been reported after Total knee arthroplasty. These are considered a devastating complication that substantially affects the clinical results and are challenging situations to treat with surgery being the mainstay of the treatment. Case Description: We report here an interesting case of a patellar tendon rupture of one knee and Quadriceps tendon rupture of the contralateral knee following simultaneous bilateral knee replacement in a case of inflammatory arthritis patient. End to end repair for Quadriceps tear and augmentation with Autologous Hamstring tendon graft was done for Patella tendon rupture. OUTCOME: Patient was followed up for a period of 1 year and there was no Extension lag with a flexion of 100 degrees in both the knees. DISCUSSION: The key learning points and important aspects of diagnosing these injuries early and the management techniques are described in this unique case of bilateral extensor mechanism disruption following knee replacements.

  15. Prevention of hamstring injuries in male soccer : Exercise programs and return to play

    OpenAIRE

    van der Horst, N

    2017-01-01

    The aim of the studies reported in this thesis was to investigate strategies for the prevention of hamstring injuries. Hamstring injuries are the most prevalent muscle injury in soccer. In spite of efforts to reduce the occurrence of hamstring injuries in soccer, injury rates have not decreased over the last three decades. Therefore, research on hamstring injury prevention is necessary to reduce hamstring injury rates. Exercise programs to reduce soccer injuries are easy to implement during r...

  16. Prevalence and pattern of gluteus medius and minimus tendon pathology and muscle atrophy in older individuals using MRI

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Andrew S. [University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Long, Suzanne S.; Zoga, Adam C.; Read, Paul J.; Deely, Diane M.; Parker, Laurence; Morrison, William B. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States)

    2015-12-15

    To evaluate gluteus medius and minimus tendon pathology and muscle atrophy in older individuals using MRI. A retrospective MRI study of 185 individuals was performed. The inclusion criterion was age ≥50. Exclusion criteria were hip surgery, fracture, infection, tumor, or inadequate image quality. Greater trochanteric bursitis was graded none, mild, moderate, or severe. Gluteus medius, gluteus minimus, and iliopsoas tendinopathy was graded normal, tendinosis, low-grade partial tear, high-grade partial tear, or full thickness tear. Gluteus medius, gluteus minimus, tensor fascia lata, and iliopsoas muscle atrophy was scored using a standard scale. Insertion site of tendinopathy and location of muscle atrophy were assessed. Descriptive and statistical analysis was performed. There was increasing greater trochanteric bursitis and gluteus medius and minimus tendinopathy and atrophy with advancing age with moderate to strong positive associations (p < 0.0001) for age and tendinopathy, age and atrophy, bursitis and tendinopathy, and tendinopathy and atrophy for the gluteus medius and minimus. There is a weak positive association (p < 0.0001) for age and tensor fascia lata atrophy, and no statistically significant association between age and tendinopathy or between age and atrophy for the iliopsoas. Fisher's exact tests were statistically significant (p < 0.0001) for insertion site of tendon pathology and location of muscle atrophy for the gluteus medius. Gluteus medius and minimus tendon pathology and muscle atrophy increase with advancing age with progression of tendinosis to low-grade tendon tears to high-grade tendon tears. There is an associated progression in atrophy of these muscles, which may be important in fall-related hip fractures. (orig.)

  17. Prevalence and pattern of gluteus medius and minimus tendon pathology and muscle atrophy in older individuals using MRI

    International Nuclear Information System (INIS)

    Chi, Andrew S.; Long, Suzanne S.; Zoga, Adam C.; Read, Paul J.; Deely, Diane M.; Parker, Laurence; Morrison, William B.

    2015-01-01

    To evaluate gluteus medius and minimus tendon pathology and muscle atrophy in older individuals using MRI. A retrospective MRI study of 185 individuals was performed. The inclusion criterion was age ≥50. Exclusion criteria were hip surgery, fracture, infection, tumor, or inadequate image quality. Greater trochanteric bursitis was graded none, mild, moderate, or severe. Gluteus medius, gluteus minimus, and iliopsoas tendinopathy was graded normal, tendinosis, low-grade partial tear, high-grade partial tear, or full thickness tear. Gluteus medius, gluteus minimus, tensor fascia lata, and iliopsoas muscle atrophy was scored using a standard scale. Insertion site of tendinopathy and location of muscle atrophy were assessed. Descriptive and statistical analysis was performed. There was increasing greater trochanteric bursitis and gluteus medius and minimus tendinopathy and atrophy with advancing age with moderate to strong positive associations (p < 0.0001) for age and tendinopathy, age and atrophy, bursitis and tendinopathy, and tendinopathy and atrophy for the gluteus medius and minimus. There is a weak positive association (p < 0.0001) for age and tensor fascia lata atrophy, and no statistically significant association between age and tendinopathy or between age and atrophy for the iliopsoas. Fisher's exact tests were statistically significant (p < 0.0001) for insertion site of tendon pathology and location of muscle atrophy for the gluteus medius. Gluteus medius and minimus tendon pathology and muscle atrophy increase with advancing age with progression of tendinosis to low-grade tendon tears to high-grade tendon tears. There is an associated progression in atrophy of these muscles, which may be important in fall-related hip fractures. (orig.)

  18. MUSCLE-BONE INTERACTIONS ACROSS AGE IN MEN

    Directory of Open Access Journals (Sweden)

    Ian J. Palmer

    2006-03-01

    Full Text Available This study examined the relationship of muscular strength and lean tissue with age-related patterns in bone mineral density (BMD in men 20-81 years of age. Subjects were assigned to one of three age groups, Young Men (YM, (n = 25, 20-39 yrs, Middle-aged Men (MM (n = 24, 40-59 yrs, and Older Men (OM (n = 23, 60-81 yrs. Isotonic and isokinetic strength was assessed for the quadriceps and hamstrings muscle groups. DXA (Lunar DPX-IQ was used to measure spine, hip, and total body BMD and body composition. OM had significantly lower (p < 0.05 total lean body mass (LBM than MM and lower leg lean mass (LM than YM and MM. OM had significantly lower (p < 0.01 BMD than YM and MM at the femoral neck and total hip sites and a higher proportion of OM were osteopenic and osteoporotic at the total hip site. Isotonic and isokinetic strength for both muscle groups was positively related (p < 0.05 with the hip BMD sites (r = 0.38-.67. Leg LM also was positively related to hip BMD (r = 0.37-.58. Multiple Regression analyses determined that age and lean mass (LBM or leg LM were significant predictors (p < 0.05 of femoral neck, and total hip BMD, while lean mass (LBM or leg LM was a significant predictor (p < 0.05 of BMD at the spine and trochanter sites. Isotonic and isokinetic leg strength variables were significant predictors (p < 0.05 of the total body, total hip and trochanter BMD. In conclusion, leg strength, leg LM, and total LBM were significant predictors of BMD in men, independent of age. These findings emphasize the importance of maintaining lean body mass for the bone health of aging men

  19. Stem Cell Applications in Tendon Disorders: A Clinical Perspective

    Directory of Open Access Journals (Sweden)

    Mark Young

    2012-01-01

    Full Text Available Tendon injuries are a common cause of morbidity and a significant health burden on society. Tendons are structural tissues connecting muscle to bone and are prone to tearing and tendinopathy, an overuse or degenerative condition that is characterized by failed healing and cellular depletion. Current treatments, for tendon tear are conservative, surgical repair or surgical scaffold reconstruction. Tendinopathy is treated by exercises, injection therapies, shock wave treatments or surgical tendon debridement. However, tendons usually heal with fibrosis and scar tissue, which has suboptimal tensile strength and is prone to reinjury, resulting in lifestyle changes with activity restriction. Preclinical studies show that cell therapies have the potential to regenerate rather than repair tendon tissue, a process termed tenogenesis. A number of different cell lines, with varying degrees of differentiation, have being evaluated including stem cells, tendon derived cells and dermal fibroblasts. Even though cellular therapies offer some potential in treating tendon disorders, there have been few published clinical trials to determine the ideal cell source, the number of cells to administer, or the optimal bioscaffold for clinical use.

  20. Prevention of hamstring injuries in male soccer : Exercise programs and return to play

    NARCIS (Netherlands)

    van der Horst, N

    2017-01-01

    The aim of the studies reported in this thesis was to investigate strategies for the prevention of hamstring injuries. Hamstring injuries are the most prevalent muscle injury in soccer. In spite of efforts to reduce the occurrence of hamstring injuries in soccer, injury rates have not decreased over

  1. One-stage Pelnac Reconstruction in Full-thickness Skin Defects with Bone or Tendon Exposure

    Directory of Open Access Journals (Sweden)

    Xianghong Lou, MS

    2018-03-01

    Full Text Available Summary:. Dermal regeneration template, such as Integra and Pelnac, was originally designed for treating large area burn injury by inducing regeneration of dermis. To date, it has been widely applied in various acute and chronic wound sites. The present study demonstrated that application of artificial dermis alone induced 1-stage wound healing for wounds with bone or tendon exposure that should usually be repaired by flap surgery. Eight patients who presented with skin defects with bone and/or tendon exposure were treated by 1-stage Pelnac approach. All wounds healed within 20 weeks without skin graft or flap surgery. The wound area was reconstructed by nearly normal skin structure and linear scar. In the case of scalp defect, evidence of hair follicle cell migration and regeneration during healing process was observed. Thereby, the 1-stage Pelnac reconstitution can be considered as a novel method for inducing regrowth of epidermis and hair follicles to cure large full-thickness skin defect with bone and tendon exposure in 1 stage.

  2. Effects of Stretching by P.N.F and Harmonic Techniques on Hamstring Flexibility

    Directory of Open Access Journals (Sweden)

    Hassan Shakeri

    2006-01-01

    Full Text Available Objective: Improving of muscle flexibility is an important issue in physiotherapy and sport sciences. There are many methods for increasing muscle length and decreasing muscle stiffness. In research findings, PNF method has been found to be better than static and ballistic methods. There is another method named Harmonic technique (introduced by E. Lederman 1997 that has been claimed to be more effective, but there is not enough documentation about this claim. Aim of this study was to compare effects of stretching by PNF and harmonic techniques on hamstring flexibility. Materials & Methods: This research is a RCT study in that 45 colledge students aged 18-35 years were arranged in three groups (Harmonic, P.N.F, and control. Subjects haven’t had any painful pathology in low-back and lower extremities for last six months. Subjects had limited hamstring length (20 degrees deficiency in Active-Knee-Extension test and hadn’t professional sport activities. Dependent variablies were muscle stiffness and hamstring length which popliteal angle in AKE test was its indirect index. In pilot study, reliability of measurement of these variables were approved. Then hamstring muscle of subjects in harmonic and PNF groups were stretched by harmonic and PNF methods for six weeks, 5 minute per day and 3d/wks, whereas control group hadn’t any exercise. Results: Findings of this study showed that in both used techniques, changes of hamstring length were significant (P=0.000, but in control group there wasn’t significant change. There wasn’t significant differences between changes of hamstring length in PNF and Harmonic groups. Only in harmonic group, muscle stiffness had significant changes (P<0.03. Conclusion: According to findings of this research, both harmonic and PNF methods equally increased length of hamstring, and harmonic technique can be used as an alternative stretching method for other techniques. Maybe harmonic technique is better than PNF

  3. Bone tunnel change develops within two weeks of double-bundle anterior cruciate ligament reconstruction using hamstring autograft: A comparison of different postoperative immobilization periods using computed tomography.

    Science.gov (United States)

    Shimizu, Ryo; Adachi, Nobuo; Ishifuro, Minoru; Nakamae, Atsuo; Ishikawa, Masakazu; Deie, Masataka; Ochi, Mitsuo

    2017-10-01

    The purpose of this study was to evaluate bone tunnel changes following anterior cruciate ligament (ACL) reconstruction during the early postoperative period using computed tomography (CT), and to understand the impact of postoperative immobilization on these changes. Twenty patients who underwent double-bundle ACL reconstruction using hamstring tendon autografts were included. We subcategorized patients into two groups: patients who underwent isolated ACL reconstruction and had three days of knee immobilization (Group A, n=10); and patients with concomitant meniscus injuries who underwent ACL reconstruction and meniscus repair simultaneously (Group B, n=10) had their knees immobilized for two weeks after surgery. Bone tunnel enlargement was evaluated using CT imaging at one to three days, two weeks, one month, three months and six months after surgery. The cross-sectional area of the femoral and tibial tunnels was measured, and enlargement rate was calculated. The tunnel center location at two weeks after surgery was also evaluated. The mean cross-sectional area adjacent to the joint space of the femoral and tibial tunnels significantly increased immediately after surgery, especially in the first month (P0.01). There was no significant difference in tunnel enlargement rate between group A and B. Tunnel center location changed even in the first two weeks. Bone tunnel enlargement following double-bundle ACL reconstruction occurred at an earlier time point after surgery than anticipated. Postoperative immobilization could not prevent bone tunnel enlargement, but might prevent tunnel migration. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Electrical stimulation-induced Gluteal and Hamstring muscle activation can reduce sitting pressure in individuals with a spinal cord injury

    NARCIS (Netherlands)

    Janssen, T. W J; De Koning, A.; Legemate, K. J A; Smit, C. A J

    2010-01-01

    Individuals with spinal cord injury (SCI) are at high risk of developing pressure sores, in part due to high sitting pressures under the buttocks. PURPOSE: To evaluate the effect of ES-induced activation of the gluteal and hamstring muscles on the sitting pressure in individuals with SCI. METHODS:

  5. Functional and Neuromuscular Changes in the Hamstrings After Drop Jumps and Leg Curls

    Science.gov (United States)

    Sarabon, Nejc; Panjan, Andrej; Rosker, Jernej; Fonda, Borut

    2013-01-01

    The purpose of this study was to use a holistic approach to investigate changes in jumping performance, kinaesthesia, static balance, isometric strength and fast stepping on spot during a 5-day recovery period, following an acute bout of damaging exercise consisted of drop jumps and leg curls, where specific emphasis was given on the hamstring muscles. Eleven young healthy subjects completed a series of highly intensive damaging exercises for their hamstring muscles. Prior to the exercise, and during the 5-day recovery period, the subjects were tested for biochemical markers (creatine kinase, aspartate aminotransferase, and lactate dehydrogenase), perceived pain sensation, physical performance (squat jump, counter movement jump, maximal frequency leg stamping, maximal isometric torque production and maximally explosive isometric torque production), kinaesthesia (active torque tracking) and static balance. We observed significant decreases in maximal isometric knee flexion torque production, the rate of torque production, and majority of the parameters for vertical jump performance. No alterations were found in kinaesthesia, static balance and fast stepping on spot. The highest drop in performance and increase in perceived pain sensation generally occurred 24 or 48 hours after the exercise. Damaging exercise substantially alters the neuromuscular functions of the hamstring muscles, which is specifically relevant for sports and rehabilitation experts, as the hamstrings are often stretched to significant lengths, in particular when the knee is extended and hip flexed. These findings are practically important for recovery after high-intensity trainings for hamstring muscles. Key Points Hamstring function is significantly reduced following specifically damaging exercise. It fully recovers 120 hours after the exercise. Prevention of exercise-induced muscle damage is cruicial for maintaining normal training regime. PMID:24149148

  6. THE MID - TERM EFFECT OF KINESIO TAPING ON PEAK POWER OF QUADRICEPS AND HAMSTRING MUSCLES AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    Amel Khabazan Mahdi

    2017-01-01

    Full Text Available Purpose: The aim of this study was to assess mid- term effect of Kinesio tape on peak power of quadriceps and hamstrings muscles after ACL reconstruction 24 hours after taping. Material: Thirty six men who had undergone ACL reconstruction and completed physiotherapy periods (6 months were assigned to no taping, placebo and taping groups. Peak power was tested before and 24 hours after taping by Isokinetic dynamometry. Data was analyzed by SPSS software 19. ANOVA and post hoc test (LSD were used for interpretive analysis. Results: The results showed that the effect of Kinesio tape on peak power of quadriceps muscles at velocities of 180°/s and 300°/s was significant. In the hamstring muscles, significant effects were obtained at velocities of 60°/s, 180°/s & 300°/s. Conclusion: Positive impacts of Kinesio tape on muscular peak power among athletes who had ACL reconstruction were observed. Regardless of psychological effect and reducing re - injury fear, Kinesio - tape causes to stabilize and increase effective range of motion of the knee, so it is recommended that in the explosive training, athletes who have ACL reconstruction should use tape to reduce the probability of re-injury and increase muscle power.

  7. Duration Dependent Effect of Static Stretching on Quadriceps and Hamstring Muscle Force

    Directory of Open Access Journals (Sweden)

    Leyla Alizadeh Ebadi

    2018-03-01

    Full Text Available The aim of this study was to determine the acute effect of static stretching on hamstring and quadriceps muscles’ isokinetic strength when applied for various durations to elite athletes, to investigate the effect of different static stretching durations on isokinetic strength, and finally to determine the optimal stretching duration. Fifteen elite male athletes from two different sport branches (10 football and five basketball participated in this study. Experimental protocol was designed as 17 repetitive static stretching exercises for hamstring and quadriceps muscle groups according to the indicated experimental protocols; ((A 5 min jogging; (B 5 min jogging followed by 15 s static stretching; (C 5 min jogging followed by 30 s static stretching; (D 5 min jogging, followed by static stretching for 45 s. Immediately after each protocol, an isokinetic strength test consisting of five repetitions at 60°/s speed and 20 repetitions at 180°/s speed was recorded for the right leg by the Isomed 2000 device. Friedman variance analysis test was employed for data analysis. According to the analyzes, it was observed that 5 min jogging and 15 s stretching exercises increased the isokinetic strength, whereas 30 and 45 s stretching exercises caused a decrease.

  8. Hamstring injury in AFL footballers - the prognostic value and nature of MR imaging findings

    International Nuclear Information System (INIS)

    Slavotinek, J.; Fon, G.T.

    2002-01-01

    Full text: The aim of this study was to examine relationships between MR parameters of hamstring injury and the amount of time lost from competition in Australian Rules footballers. Thirty seven footballers with suspected hamstring injury underwent T1 and inversion recovery T2 turbo spin-echo sequences in axial and sagittal planes. Presence and dimension of abnormal focal intramuscular and / or extramuscular T2 hyperintensity was independently recorded by two radiologists and the percentage abnormal cross sectional muscle area and abnormal muscle volume were measured from T2-weighted images depicting extent of muscle injury. MR detected hamstring muscle and linear extramuscle T2 hyperintensity in 30 (81%) and 25 (68%) of 37 athletes respectively, the long head of biceps being the dominant site of injury in 21 cases.There was a relationship between days lost from competition and percentage abnormal muscle area (r = 0.63, p 0.001) and volume of muscle affected (r = 0.46, p 0.01) with only a trend for linear extramuscular T2 hyperintensity (r = 0.33, p = 0.12) being demonstrated. Hamstring injury most frequently involved the long head of biceps femoris and recovery time was related to MR measurements such as the percentage of abnormal muscle area and volume of muscle injury. Copyright (2002) Blackwell Science Pty Ltd

  9. Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode.

    Science.gov (United States)

    Farup, J; Rahbek, S K; Vendelbo, M H; Matzon, A; Hindhede, J; Bejder, A; Ringgard, S; Vissing, K

    2014-10-01

    In a comparative study, we investigated the effects of maximal eccentric or concentric resistance training combined with whey protein or placebo on muscle and tendon hypertrophy. 22 subjects were allocated into either a high-leucine whey protein hydrolysate + carbohydrate group (WHD) or a carbohydrate group (PLA). Subjects completed 12 weeks maximal knee extensor training with one leg using eccentric contractions and the other using concentric contractions. Before and after training cross-sectional area (CSA) of m. quadriceps and patellar tendon CSA was quantified with magnetic resonance imaging and a isometric strength test was used to assess maximal voluntary contraction (MVC) and rate of force development (RFD). Quadriceps CSA increased by 7.3 ± 1.0% (P tendon CSA increased by 14.9 ± 3.1% (P effect of contraction mode. MVC and RFD increased by 15.6 ± 3.5% (P effects. In conclusion, high-leucine whey protein hydrolysate augments muscle and tendon hypertrophy following 12 weeks of resistance training - irrespective of contraction mode. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. A benchtop biorobotic platform for in vitro observation of muscle-tendon dynamics with parallel mechanical assistance from an elastic exoskeleton.

    Science.gov (United States)

    Robertson, Benjamin D; Vadakkeveedu, Siddarth; Sawicki, Gregory S

    2017-05-24

    We present a novel biorobotic framework comprised of a biological muscle-tendon unit (MTU) mechanically coupled to a feedback controlled robotic environment simulation that mimics in vivo inertial/gravitational loading and mechanical assistance from a parallel elastic exoskeleton. Using this system, we applied select combinations of biological muscle activation (modulated with rate-coded direct neural stimulation) and parallel elastic assistance (applied via closed-loop mechanical environment simulation) hypothesized to mimic human behavior based on previously published modeling studies. These conditions resulted in constant system-level force-length dynamics (i.e., stiffness), reduced biological loads, increased muscle excursion, and constant muscle average positive power output-all consistent with laboratory experiments on intact humans during exoskeleton assisted hopping. Mechanical assistance led to reduced estimated metabolic cost and MTU apparent efficiency, but increased apparent efficiency for the MTU+Exo system as a whole. Findings from this study suggest that the increased natural resonant frequency of the artificially stiffened MTU+Exo system, along with invariant movement frequencies, may underlie observed limits on the benefits of exoskeleton assistance. Our novel approach demonstrates that it is possible to capture the salient features of human locomotion with exoskeleton assistance in an isolated muscle-tendon preparation, and introduces a powerful new tool for detailed, direct examination of how assistive devices affect muscle-level neuromechanics and energetics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The biomechanics of running in athletes with previous hamstring injury: A case-control study.

    Science.gov (United States)

    Daly, C; Persson, U McCarthy; Twycross-Lewis, R; Woledge, R C; Morrissey, D

    2016-04-01

    Hamstring injury is prevalent with persistently high reinjury rates. We aim to inform hamstring rehabilitation by exploring the electromyographic and kinematic characteristics of running in athletes with previous hamstring injury. Nine elite male Gaelic games athletes who had returned to sport after hamstring injury and eight closely matched controls sprinted while lower limb kinematics and muscle activity of the previously injured biceps femoris, bilateral gluteus maximus, lumbar erector spinae, rectus femoris, and external oblique were recorded. Intergroup comparisons of muscle activation ratios and kinematics were performed. Previously injured athletes demonstrated significantly reduced biceps femoris muscle activation ratios with respect to ipsilateral gluteus maximus (maximum difference -12.5%, P = 0.03), ipsilateral erector spinae (maximum difference -12.5%, P = 0.01), ipsilateral external oblique (maximum difference -23%, P = 0.01), and contralateral rectus femoris (maximum difference -22%, P = 0.02) in the late swing phase. We also detected sagittal asymmetry in hip flexion (maximum 8°, P = 0.01), pelvic tilt (maximum 4°, P = 0.02), and medial rotation of the knee (maximum 6°, P = 0.03) effectively putting the hamstrings in a lengthened position just before heel strike. Previous hamstring injury is associated with altered biceps femoris associated muscle activity and potentially injurious kinematics. These deficits should be considered and addressed during rehabilitation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Prolonged electrical stimulation-induced gluteal and hamstring muscle activation and sitting pressure in spinal cord injury: Effect of duty cycle

    NARCIS (Netherlands)

    MSc Karin J.A. Legemate; MD Christof A. J. Smit; MSc Anja de Koning; PhD Sonja de Groot; MD, PhD Janneke M. Stolwijk-Swuste; PhD Thomas W.H. Janssen

    2013-01-01

    Abstract—Pressure ulcers (PUs) are highly prevalent in people with spinal cord injury (SCI). Electrical stimulation (ES) activates muscles and might reduce risk factors. Our objectives were to study and compare the effects of two duty cycles during 3 h of ES-induced gluteal and hamstring activation

  13. Prolonged electrical stimulation-induced gluteal and hamstring muscle activation and sitting pressure in spinal cord injury : Effect of duty cycle

    NARCIS (Netherlands)

    Smit, Christof A. J.; Legemate, Karin J. A.; de Koning, Anja; de Groot, Sonja; Stolwijk-Swuste, Janneke M.; Janssen, Thomas W. J.

    2013-01-01

    Pressure ulcers (PUs) are highly prevalent in people with spinal cord injury (SCI). Electrical stimulation (ES) activates muscles and might reduce risk factors. Our objectives were to study and compare the effects of two duty cycles during 3 h of ES-induced gluteal and hamstring activation on

  14. Comparison of gluteal and hamstring activation during five commonly used plyometric exercises.

    Science.gov (United States)

    Struminger, Aaron H; Lewek, Michael D; Goto, Shiho; Hibberd, Elizabeth; Blackburn, J Troy

    2013-08-01

    Anterior cruciate ligament injuries occur frequently in athletics, and anterior cruciate ligament injury prevention programs may decrease injury risk. However, previous prevention programs that include plyometrics use a variety of exercises with little justification of exercise inclusion. Because gluteal and hamstring activation is thought to be important for preventing knee injuries, the purpose of this study was to determine which commonly used plyometric exercises produce the greatest activation of the gluteals and hamstrings. EMG (Electromyography) amplitudes of the hamstring and gluteal muscles during preparatory and loading phases of landing were recorded in 41 subjects during 5 commonly used plyometric exercises. Repeated measures ANOVAs (Analysis of Variance) were used on 36 subjects to examine differences in muscle activation. Differences in hamstring (Pplyometric exercises, their removal from injury prevention programs may be warranted without affecting program efficacy. © 2013.

  15. The effect of dynamic knee-extension exercise on patellar tendon and quadriceps femoris muscle glucose uptake in humans studied by positron emission tomography

    DEFF Research Database (Denmark)

    Kalliokoski, Kari K; Langberg, Henning; Ryberg, Ann Kathrine

    2005-01-01

    Both tendon and peritendinous tissue show evidence of metabolic activity, but the effect of acute exercise on substrate turnover is unknown. We therefore examined the influence of acute exercise on glucose uptake in the patellar and quadriceps tendons during dynamic exercise in humans. Glucose...... that tendon glucose uptake is increased during exercise. However, the increase in tendon glucose uptake is less pronounced than in muscle and the increases are uncorrelated. Thus tendon glucose uptake is likely to be regulated by mechanisms independently of those regulating skeletal muscle glucose uptake....... uptake was measured in five healthy men in the patellar and quadriceps tendons and the quadriceps femoris muscle at rest and during dynamic knee-extension exercise (25 W) using positron emission tomography and [18F]-2-fluoro-2-deoxy-D-glucose ([18F]FDG). Glucose uptake index was calculated by dividing...

  16. Interseason variability in isokinetic strength and poor correlation with Nordic hamstring eccentric strength in football players.

    Science.gov (United States)

    van Dyk, N; Witvrouw, E; Bahr, R

    2018-04-25

    In elite sport, the use of strength testing to establish muscle function and performance is common. Traditionally, isokinetic strength tests have been used, measuring torque during concentric and eccentric muscle action. A device that measures eccentric hamstring muscle strength while performing the Nordic hamstring exercise is now also frequently used. The study aimed to investigate the variability of isokinetic muscle strength over time, for example, between seasons, and the relationship between isokinetic testing and the new Nordic hamstring exercise device. All teams (n = 18) eligible to compete in the premier football league in Qatar underwent a comprehensive strength assessment during their periodic health evaluation at Aspetar Orthopaedic and Sports Medicine Hospital in Qatar. Isokinetic strength was investigated for measurement error, and correlated to Nordic hamstring exercise strength. Of the 529 players included, 288 players had repeated tests with 1/2 seasons between test occasions. Variability (measurement error) between test occasions was substantial, as demonstrated by the measurement error (approximately 25 Nm, 15%), whether separated by 1 or 2 seasons. Considering hamstring injuries, the same pattern was observed among injured (n = 60) and uninjured (n = 228) players. A poor correlation (r = .35) was observed between peak isokinetic hamstring eccentric torque and Nordic hamstring exercise peak force. The strength imbalance between limbs calculated for both test modes was not correlated (r = .037). There is substantial intraindividual variability in all isokinetic test measures, whether separated by 1 or 2 seasons, irrespective of injury. Also, eccentric hamstring strength and limb-to-limb imbalance were poorly correlated between the isokinetic and Nordic hamstring exercise tests. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. HAMSTRING INJURY REHABILITATION AND PREVENTION OF REINJURY USING LENGTHENED STATE ECCENTRIC TRAINING: A NEW CONCEPT

    Science.gov (United States)

    Tim, Tyler; McHugh, Malachy

    2012-01-01

    Back ground and Purpose: Hamstring injury is a common occurrence in sport and there has been limited success in reducing this rate of recurrence to date. Description of Topic with Related Evidence: High speed running requires eccentric strength when the hamstring muscles are in a lengthened state. The lengthened state occurs when the hip is in flexion and the lower leg moves into extension, thus lengthening the two joint hamstring muscle over both articulations upon which they act. There is evidence to suggest that athletes who have sustained a hamstring strain lack strength when the muscle is utilized during performance in a lengthened state. Purpose: To examine the risk factors contributing to such a high recurrence rate and propose a unique rehabilitation strategy addressing these factors in order to decrease the rate of reinjury. Discussion/Relation to Clinical Practice: Failing to increase an athlete's eccentric strength in a lengthened position after a hamstring injury may predispose an athlete to subsequent reinjury. Incorporating lengthened state eccentric training may help reduce the rate of reinjury. Level of Evidence: Level 5 PMID:22666648

  18. Hamstrings strength imbalance in professional football (soccer) players in Australia.

    Science.gov (United States)

    Ardern, Clare L; Pizzari, Tania; Wollin, Martin R; Webster, Kate E

    2015-04-01

    The aim of this study was to describe the isokinetic thigh muscle strength profile of professional male football players in Australia. Concentric (60° and 240°·s(-1)) and eccentric (30° and 120°·s(-1)) hamstrings and quadriceps isokinetic strength was measured with a HUMAC NORM dynamometer. The primary variables were bilateral concentric and eccentric hamstring and quadriceps peak torque ratios, concentric hamstring-quadriceps peak torque ratios, and mixed ratios (eccentric hamstring 30°·s(-1) ÷ concentric quadriceps 240°·s(-1)). Hamstring strength imbalance was defined as deficits in any 2 of: bilateral concentric hamstring peak torque ratio imbalance. Athletes with strength imbalance had significantly reduced concentric and eccentric bilateral hamstring peak torque ratios at all angular velocities tested; and reduced eccentric quadriceps peak torque (30°·s(-1)) in their stance leg, compared with those without strength imbalance. Approximately, 1 in 4 players had preseason hamstring strength imbalance; and all strength deficits were observed in the stance leg. Concentric and eccentric hamstrings strength imbalance may impact in-season football performance and could have implications for the future risk of injury.

  19. Proximal Neuromuscular Control Protects Against Hamstring Injuries in Male Soccer Players: A Prospective Study With Electromyography Time-Series Analysis During Maximal Sprinting.

    Science.gov (United States)

    Schuermans, Joke; Danneels, Lieven; Van Tiggelen, Damien; Palmans, Tanneke; Witvrouw, Erik

    2017-05-01

    With their unremittingly high incidence rate and detrimental functional repercussions, hamstring injuries remain a substantial problem in male soccer. Proximal neuromuscular control ("core stability") is considered to be of key importance in primary and secondary hamstring injury prevention, although scientific evidence and insights on the exact nature of the core-hamstring association are nonexistent at present. The muscle activation pattern throughout the running cycle would not differ between participants based on injury occurrence during follow-up. Case-control study; Level of evidence, 3. Sixty amateur soccer players participated in a multimuscle surface electromyography (sEMG) assessment during maximal acceleration to full-speed sprinting. Subsequently, hamstring injury occurrence was registered during a 1.5-season follow-up period. Hamstring, gluteal, and trunk muscle activity time series during the airborne and stance phases of acceleration were evaluated and statistically explored for a possible causal association with injury occurrence and absence from sport during follow-up. Players who did not experience a hamstring injury during follow-up had significantly higher amounts of gluteal muscle activity during the front swing phase ( P = .027) and higher amounts of trunk muscle activity during the backswing phase of sprinting ( P = .042). In particular, the risk of sustaining a hamstring injury during follow-up lowered by 20% and 6%, with a 10% increment in normalized muscle activity of the gluteus maximus during the front swing and the trunk muscles during the backswing, respectively ( P hamstring injury occurrence in male soccer players. Higher amounts of gluteal and trunk muscle activity during the airborne phases of sprinting were associated with a lower risk of hamstring injuries during follow-up. Hence, the present results provide a basis for improved, evidence-based rehabilitation and prevention, particularly focusing on increasing neuromuscular

  20. The Bone-Muscle Relationship in Men and Women

    Directory of Open Access Journals (Sweden)

    Thomas F. Lang

    2011-01-01

    Full Text Available Muscle forces are a strong determinant of bone structure, particularly during the process of growth and development. The gender divergence in the bone-muscle relationship becomes strongly evident during adolescence. In females, growth is characterized by increased estrogen levels and increased mass and strength of bone relative to that of muscle, whereas in men, increases in testosterone fuel large increases in muscle, resulting in muscle forces that coincide with a large growth in bone dimensions and strength. In adulthood, significant age-related losses are observed for both bone and muscle tissues. Large decrease in estrogen levels in women appears to diminish the skeleton's responsiveness to exercise more than in men. In contrast, the aging of the muscle-bone axis in men is a function of age related declines in both hormones. In addition to the well-known age related changes in the mechanical loading of bone by muscle, newer studies appear to provide evidence of age- and gender-related variations in molecular signaling between bone and muscle that are independent of purely mechanical interactions. In summary, gender differences in the acquisition and age-related loss in bone and muscle tissues may be important for developing gender-specific strategies for using exercise to reduce bone loss with aging.

  1. The anatomical footprint of the Achilles tendon: a cadaveric study.

    Science.gov (United States)

    Ballal, M S; Walker, C R; Molloy, A P

    2014-10-01

    We dissected 12 fresh-frozen leg specimens to identify the insertional footprint of each fascicle of the Achilles tendon on the calcaneum in relation to their corresponding muscles. A further ten embalmed specimens were examined to confirm an observation on the retrocalcaneal bursa. The superficial part of the insertion of the Achilles tendon is represented by fascicles from the medial head of the gastrocnemius muscle, which is inserted over the entire width of the inferior facet of the calcaneal tuberosity. In three specimens this insertion was in continuity with the plantar fascia in the form of periosteum. The deep part of the insertion of the Achilles tendon is made of fascicles from the soleus tendon, which insert on the medial aspect of the middle facet of the calcaneal tuberosity, while the fascicles of the lateral head of the gastrocnemius tendon insert on the lateral aspect of the middle facet of the calcaneal tuberosity. A bicameral retrocalcaneal bursa was present in 15 of the 22 examined specimens. This new observation and description of the insertional footprint of the Achilles tendon and the retrocalcaneal bursa may allow a better understanding of the function of each muscular part of the gastrosoleus complex. This may have clinical relevance in the treatment of Achilles tendinopathies. ©2014 The British Editorial Society of Bone & Joint Surgery.

  2. Towards human exploration of space: the THESEUS review series on muscle and bone research priorities.

    Science.gov (United States)

    Lang, Thomas; Van Loon, Jack J W A; Bloomfield, Susan; Vico, Laurence; Chopard, Angele; Rittweger, Joern; Kyparos, Antonios; Blottner, Dieter; Vuori, Ilkka; Gerzer, Rupert; Cavanagh, Peter R

    2017-01-01

    Without effective countermeasures, the musculoskeletal system is altered by the microgravity environment of long-duration spaceflight, resulting in atrophy of bone and muscle tissue, as well as in deficits in the function of cartilage, tendons, and vertebral disks. While inflight countermeasures implemented on the International Space Station have evidenced reduction of bone and muscle loss on low-Earth orbit missions of several months in length, important knowledge gaps must be addressed in order to develop effective strategies for managing human musculoskeletal health on exploration class missions well beyond Earth orbit. Analog environments, such as bed rest and/or isolation environments, may be employed in conjunction with large sample sizes to understand sex differences in countermeasure effectiveness, as well as interaction of exercise with pharmacologic, nutritional, immune system, sleep and psychological countermeasures. Studies of musculoskeletal biomechanics, involving both human subject and computer simulation studies, are essential to developing strategies to avoid bone fractures or other injuries to connective tissue during exercise and extravehicular activities. Animal models may be employed to understand effects of the space environment that cannot be modeled using human analog studies. These include studies of radiation effects on bone and muscle, unraveling the effects of genetics on bone and muscle loss, and characterizing the process of fracture healing in the mechanically unloaded and immuno-compromised spaceflight environment. In addition to setting the stage for evidence-based management of musculoskeletal health in long-duration space missions, the body of knowledge acquired in the process of addressing this array of scientific problems will lend insight into the understanding of terrestrial health conditions such as age-related osteoporosis and sarcopenia.

  3. Hamstring injury prevention in soccer: Before or after training?

    Science.gov (United States)

    Lovell, R; Knox, M; Weston, M; Siegler, J C; Brennan, S; Marshall, P W M

    2018-02-01

    We examined the effects of a 12-week program of Nordic hamstring exercises (NHE), administered before or after football training, upon eccentric hamstring strength, muscle activity, and architectural adaptations. Amateur soccer players were randomized into three groups. The control group (CON; n=11) undertook core stability exercises, whereas a periodized NHE program was delivered either before (NHE BEF ; n=10) or after (NHE AFT ; n=14) biweekly training sessions. Outcome measures included peak torque and concomitant normalized peak surface electromyography signals (sEMG) of the biceps femoris (BF) and medial hamstring (MH) muscles during knee flexor maximal eccentric contractions, performed at 30°·s -1 . Ultrasonography was used to determine BF muscle thickness, muscle fiber pennation angle, and fascicle length. Performing the NHE derived likely moderate peak torque increases in both NHE BEF (+11.9%; 90% confidence interval: 3.6%-20.9%) and NHE AFT (+11.6%; 2.6%-21.5%) vs CON. Maximum sEMG increases were moderately greater in the BF of both NHE training groups vs CON. There were likely moderate increases in BF muscle thickness (+0.17 cm; 0.05-0.29 cm) and likely small pennation angle increases (+1.03°; -0.08° to 2.14°) in NHE AFT vs CON and NHE BEF . BF fascicle length increases were likely greater in NHE BEF (+1.58 cm; 0.48-2.68 cm; small effect) vs CON and NHE AFT . A 12-week eccentric hamstring strengthening program increased strength and sEMG to a similar magnitude irrespective of its scheduling relative to the football training session. However, architectural adaptations to support the strength gains differed according to the timing of the injury prevention program. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Muscle-tendon related pain in 100 patients with hip dysplasia: prevalence and associations with self-reported hip disability and muscle strength

    DEFF Research Database (Denmark)

    Jacobsen, Julie Sandell

    2017-01-01

    dysplasia. The secondary aim was to test if muscle-tendon related pain is linearly associated to self-reported hip disability and muscle strength in patients with hip dysplasia. Materials and methods One hundred patients (17 men) with a mean age of 29+9 years were included. Clinical entity approach...

  5. A new approach to assess the spasticity in hamstrings muscles using mechanomyography antagonist muscular group.

    Science.gov (United States)

    Krueger, Eddy; Scheeren, Eduardo M; Nogueira-Neto, Guilherme N; Button, Vera Lúcia da S N; Nohama, Percy

    2012-01-01

    Several pathologies can cause muscle spasticity. Modified Ashworth scale (MAS) can rank spasticity, however its results depend on the physician subjective evaluation. This study aims to show a new approach to spasticity assessment by means of MMG analysis of hamstrings antagonist muscle group (quadriceps muscle). Four subjects participated in the study, divided into two groups regarding MAS (MAS0 and MAS1). MMG sensors were positioned over the muscle belly of rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM) muscles. The range of movement was acquired with an electrogoniometer placed laterally to the knee. The system was based on a LabVIEW acquisition program and the MMG sensors were built with triaxial accelerometers. The subjects were submitted to stretching reflexes and the integral of the MMG (MMG(INT)) signal was calculated to analysis. The results showed that the MMG(INT) was greater to MAS1 than to MAS0 [muscle RF (p = 0.004), VL (p = 0.001) and VM (p = 0.007)]. The results showed that MMG was viable to detect a muscular tonus increase in antagonist muscular group (quadriceps femoris) of spinal cord injured volunteers.

  6. Oedema and fatty degeneration of the soleus and gastrocnemius muscles on MR images in patients with achilles tendon abnormalities

    International Nuclear Information System (INIS)

    Hoffmann, Adrienne; Mamisch, Nadja; Buck, Florian M.; Pfirrmann, Christian W.A.; Zanetti, Marco; Espinosa, Norman

    2011-01-01

    The purpose of this study was to evaluate the frequency of oedema and fatty degeneration of the soleus and gastrocnemius muscles in patients with Achilles tendon abnormalities. Forty-five consecutive patients (mean 51 years; range 14-84 years) with achillodynia were examined with magnetic resonance (MR) images of the calf. The frequency of oedema and fatty degeneration in the soleus and gastrocnemius muscles was determined in patients with normal tendons, tendinopathy and in patients with a partial tear or a complete tear of the Achilles tendon. Oedema was encountered in 35% (7/20) of the patients with tendinopathy (n = 20; range 13-81 years), and in 47% (9/19) of the patients with partial tears or complete tears (n = 19; 28-78 years). Fatty degeneration was encountered in 10% (2/20) of the patients with tendinopathy, and in 32% (6/19) of the patients with tears. The prevalence of fatty degeneration was significantly more common in patients with a partial or complete tear compared with the patients with a normal Achilles tendon (p = 0.032 and p = 0.021, respectively). Oedema and fatty degeneration of the soleus and gastrocnemius muscles are common in patients with Achilles tendon abnormalities. (orig.)

  7. Molecular characterization and function of tenomodulin, a marker of tendons and ligaments that integrate musculoskeletal components

    Directory of Open Access Journals (Sweden)

    Chisa Shukunami, DDS, PhD

    2016-11-01

    Full Text Available Tendons and ligaments are dense fibrous bands of connective tissue that integrate musculoskeletal components in vertebrates. Tendons connect skeletal muscles to the bone and function as mechanical force transmitters, whereas ligaments bind adjacent bones together to stabilize joints and restrict unwanted joint movement. Fibroblasts residing in tendons and ligaments are called tenocytes and ligamentocytes, respectively. Tenomodulin (Tnmd is a type II transmembrane glycoprotein that is expressed at high levels in tenocytes and ligamentocytes, and is also present in periodontal ligament cells and tendon stem/progenitor cells. Tnmd is related to chondromodulin-1 (Chm1, a cartilage-derived angiogenesis inhibitor, and both Tnmd and Chm1 are expressed in the CD31− avascular mesenchyme. The conserved C-terminal hydrophobic domain of these proteins, which is characterized by the eight Cys residues to form four disulfide bonds, may have an anti-angiogenic function. This review highlights the molecular characterization and function of Tnmd, a specific marker of tendons and ligaments.

  8. Effect of Footprint Preparation on Tendon-to-Bone Healing: A Histologic and Biomechanical Study in a Rat Rotator Cuff Repair Model.

    Science.gov (United States)

    Nakagawa, Haruhiko; Morihara, Toru; Fujiwara, Hiroyoshi; Kabuto, Yukichi; Sukenari, Tsuyoshi; Kida, Yoshikazu; Furukawa, Ryuhei; Arai, Yuji; Matsuda, Ken-Ichi; Kawata, Mitsuhiro; Tanaka, Masaki; Kubo, Toshikazu

    2017-08-01

    To compare the histologic and biomechanical effects of 3 different footprint preparations for repair of tendon-to-bone insertions and to assess the behavior of bone marrow-derived cells in each method of insertion repair. We randomized 81 male Sprague-Dawley rats and green fluorescent protein-bone marrow chimeric rats into 3 groups. In group A, we performed rotator cuff repair after separating the supraspinatus tendon from the greater tuberosity and removing the residual tendon tissue. In group B, we also drilled 3 holes into the footprint. The native fibrocartilage was preserved in groups A and B. In group C, we excavated the footprint until the cancellous bone was exposed. Histologic repair of the tendon-to-bone insertion, behavior of the bone marrow-derived cells, and ultimate force to failure were examined postoperatively. The areas of metachromasia in groups A, B, and C were 0.033 ± 0.019, 0.089 ± 0.022, and 0.002 ± 0.001 mm 2 /mm 2 , respectively, at 4 weeks and 0.029 ± 0.022, 0.090 ± 0.039, and 0.003 ± 0.001 mm 2 /mm 2 , respectively, at 8 weeks. At 4 and 8 weeks postoperatively, significantly higher cartilage matrix production was observed in group B than in group C (4 weeks, P = .002; 8 weeks, P repair tissue and biomechanical strength at the tendon-to-bone insertion after rotator cuff repair in an animal model. Drilling into the footprint and preserving the fibrocartilage can enhance repair of tendon-to-bone insertions. This method may be clinically useful in rotator cuff repair. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  9. FUNCTIONAL AND NEUROMUSCULAR CHANGES IN THE HAMSTRINGS AFTER DROP JUMPS AND LEG CURLS

    Directory of Open Access Journals (Sweden)

    Nejc Sarabon

    2013-09-01

    Full Text Available The purpose of this study was to use a holistic approach to investigate changes in jumping performance, kinaesthesia, static balance, isometric strength and fast stepping on spot during a 5-day recovery period, following an acute bout of damaging exercise consisted of drop jumps and leg curls, where specific emphasis was given on the hamstring muscles. Eleven young healthy subjects completed a series of highly intensive damaging exercises for their hamstring muscles. Prior to the exercise, and during the 5-day recovery period, the subjects were tested for biochemical markers (creatine kinase, aspartate aminotransferase, and lactate dehydrogenase, perceived pain sensation, physical performance (squat jump, counter movement jump, maximal frequency leg stamping, maximal isometric torque production and maximally explosive isometric torque production, kinaesthesia (active torque tracking and static balance. We observed significant decreases in maximal isometric knee flexion torque production, the rate of torque production, and majority of the parameters for vertical jump performance. No alterations were found in kinaesthesia, static balance and fast stepping on spot. The highest drop in performance and increase in perceived pain sensation generally occurred 24 or 48 hours after the exercise. Damaging exercise substantially alters the neuromuscular functions of the hamstring muscles, which is specifically relevant for sports and rehabilitation experts, as the hamstrings are often stretched to significant lengths, in particular when the knee is extended and hip flexed. These findings are practically important for recovery after high-intensity trainings for hamstring muscles

  10. Hamstring tightness and Scheuermann's disease a pilot study.

    Science.gov (United States)

    Fisk, J W; Baigent, M L

    1981-06-01

    The lateral radiographs of the dorsal spines of 20 patients presenting with mainly low back pain are studied. These patients had clinically evident loss of flexion in the low dorsal spine and very tight hamstring muscles. 85% of them showed definite evidence of previous Scheuermann's Disease. The possibility that tight hamstrings may be an important factor in the aetiology of this disease is discussed, and a further large scale study is proposed.

  11. A comparison of two stretching programs for hamstring muscles: A randomized controlled assessor-blinded study.

    Science.gov (United States)

    Demoulin, Christophe; Wolfs, Sébastien; Chevalier, Madeline; Granado, Caroline; Grosdent, Stéphanie; Depas, Yannick; Roussel, Nathalie; Hage, Renaud; Vanderthommen, Marc

    2016-01-01

    Most parameters regarding hamstring flexibility training programs have been investigated; however, the joint (i.e. hip or knee) on which the stretching should preferentially be focused needs to be further explored. This randomized controlled assessor-blinded study aimed to investigate the influence of this parameter. We randomly assigned 111 asymptomatic participants with tight hamstring muscles in three groups: a control group and two groups following a different home-based 8-week (five 10-minute sessions per week) hamstring stretching program (i.e. stretching performed by flexing the hip while keeping the knee extended [SH] or by first flexing the hip with a flexed knee and then extending the knee [SK]). Range of motion (ROM) of hip flexion and knee extension were measured before and after the stretching program by means of the straight leg raising test and the passive knee extension angle test, respectively. Eighty-nine participants completed the study. A significant increase in ROM was observed at post-test. Analyses showed significant group-by-time interactions for changes regarding all outcomes. Whereas the increase in hip flexion and knee extension ROM was higher in the stretching groups than in the CG (especially for the SH group p 0.05). In conclusion, the fact that both stretching programs resulted in similar results suggests no influence of the joint at which the stretching is focused upon, as assessed by the straight leg raising and knee extension angle tests.

  12. Device for lengthening of a musculotendinous unit by direct continuous traction in the sheep

    Directory of Open Access Journals (Sweden)

    Zumstein Matthias A

    2012-05-01

    Full Text Available Abstract Background Retraction, atrophy and fatty infiltration are signs subsequent to chronic rotator cuff tendon tears. They are associated with an increased pennation angle and a shortening of the muscle fibers in series. These deleterious changes of the muscular architecture are not reversible with current repair techniques and are the main factors for failed rotator cuff tendon repair. Whereas fast stretching of the retracted musculotendinous unit results in proliferation of non-contractile fibrous tissue, slow stretching may lead to muscle regeneration in terms of sarcomerogenesis. To slowly stretch the retracted musculotendinous unit in a sheep model, two here described tensioning devices have been developed and mounted on the scapular spine of the sheep using an expandable threaded rod, which has been interposed between the retracted tendon end and the original insertion site at the humeral head. Traction is transmitted in line with the musculotendinous unit by sutures knotted on the expandable threaded rod. The threaded rod of the tensioner is driven within the body through a rotating axis, which enters the body on the opposite side. The tendon end, which was previously released (16 weeks prior from its insertion site with a bone chip, was elongated with a velocity of 1 mm/day. Results After several steps of technical improvements, the tensioner proved to be capable of actively stretching the retracted and degenerated muscle back to the original length and to withstand the external forces acting on it. Conclusion This technical report describes the experimental technique for continuous elongation of the musculotendinous unit and reversion of the length of chronically shortened muscle.

  13. Accessory muscle of the flexor digitorum superficialis and its clinical implications

    Directory of Open Access Journals (Sweden)

    Edie Benedito Caetano

    Full Text Available ABSTRACT Anatomical variations of the flexor digitorum superficialis (FDS muscle and tendon unit are frequently reported by anatomists and clinicians. Anatomical muscle variations of the FDS and its tendons may include variations of muscle belly, presence of accessory or duplicate tendons, abnormal tendon connections, and absence of muscle or tendon components. Such variations may or may not have clinical implications. This report presents a case not described previously: a unilateral accessory muscle of the flexor digitorum superficialis which was connected by a thick tendon to the flexor digitorum superficialis muscle; it was directed proximally to the insertion of the medial epicondyle of the humerus, next to the superficialis head of the pronator teres muscle. The belly of the accessory muscle was positioned anterior to the median and anterior interosseous nerve. This anatomical variation is known as type V in the classification of Elliot et al. The knowledge of these anatomical variations helps hand surgeons interpret the clinical examination, particularly in the evaluation of patients who have suffered tendon injuries or show sign s of possible peripheral nerve entrapment.

  14. Osmotic pressure induced tensile forces in tendon collagen.

    Science.gov (United States)

    Masic, Admir; Bertinetti, Luca; Schuetz, Roman; Chang, Shu-Wei; Metzger, Till Hartmut; Buehler, Markus J; Fratzl, Peter

    2015-01-22

    Water is an important component of collagen in tendons, but its role for the function of this load-carrying protein structure is poorly understood. Here we use a combination of multi-scale experimentation and computation to show that water is an integral part of the collagen molecule, which changes conformation upon water removal. The consequence is a shortening of the molecule that translates into tensile stresses in the range of several to almost 100 MPa, largely surpassing those of about 0.3 MPa generated by contractile muscles. Although a complete drying of collagen would be relevant for technical applications, such as the fabrication of leather or parchment, stresses comparable to muscle contraction already occur at small osmotic pressures common in biological environments. We suggest, therefore, that water-generated tensile stresses may play a role in living collagen-based materials such as tendon or bone.

  15. Rupture of the Distal Biceps Tendon Combined with a Supinator Muscle Tear in a 51-Year-Old Woman: A Case Report

    OpenAIRE

    Nayyar, Samir; Quirno, Martin; Hasan, Saqib; Rybak, Leon; Meislin, Robert J.

    2011-01-01

    Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequen...

  16. Effects of an eccentric training programme on hamstring strain injuries in women football players

    Directory of Open Access Journals (Sweden)

    del Ama Espinosa Gurutze

    2015-09-01

    Full Text Available Study aim: to test the hypothesis that an eccentric training programme applied on women football players would reduce the hamstring injury rate by improving thigh muscle balance and, particularly, hamstring strength.

  17. Short-term strength training and the expression of myostatin and IGF-I isoforms in rat muscle and tendon: differential effects of specific contraction types.

    Science.gov (United States)

    Heinemeier, K M; Olesen, J L; Schjerling, P; Haddad, F; Langberg, H; Baldwin, K M; Kjaer, M

    2007-02-01

    In skeletal muscle, an increased expression of insulin like growth factor-I isoforms IGF-IEa and mechano-growth factor (MGF) combined with downregulation of myostatin is thought to be essential for training-induced hypertrophy. However, the specific effects of different contraction types on regulation of these factors in muscle are still unclear, and in tendon the functions of myostatin, IGF-IEa, and MGF in relation to training are unknown. Female Sprague-Dawley rats were subjected to 4 days of concentric, eccentric, or isometric training (n = 7-9 per group) of the medial gastrocnemius, by stimulation of the sciatic nerve during general anesthesia. mRNA levels for myostatin, IGF-IEa, and MGF in muscle and Achilles' tendon were measured by real-time RT-PCR. Muscle myostatin mRNA decreased in response to all types of training (2- to 8-fold) (P effect of eccentric training was greater than concentric and isometric training (P tendon, myostatin mRNA was detected, but no changes were seen after exercise. IGF-IEa and MGF increased in muscle (up to 15-fold) and tendon (up to 4-fold) in response to training (P tendon no difference was seen between training types, but in muscle the effect of eccentric training was greater than concentric training for both IGF-IEa and MGF (P effect than concentric (P tendon to training, and the combined changes in myostatin and IGF-IEa/MGF expression could explain the important effect of eccentric actions for muscle hypertrophy.

  18. Rupture of the Distal Biceps Tendon Combined with a Supinator Muscle Tear in a 51-Year-Old Woman: A Case Report

    Directory of Open Access Journals (Sweden)

    Samir Nayyar

    2011-01-01

    Full Text Available Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequent confirmation at surgery. Surgical repair was performed for the distal biceps tendon only through a single incision approach using the Endobutton technique.

  19. Effect of platelet-rich plasma on tendon-to-bone healing after rotator cuff repair in rats: an in vivo experimental study.

    Science.gov (United States)

    Hapa, Onur; Cakıcı, Hüsamettin; Kükner, Aysel; Aygün, Hayati; Sarkalan, Nazlı; Baysal, Gökhan

    2012-01-01

    The purpose of this experimental study was to analyze the effects of local autologous platelet-rich plasma (PRP) injection on tendon-to-bone healing in a rotator cuff repair model in rats. Rotator cuff injury was created in 68 left shoulders of rats. PRP was obtained from the blood of an additional 15 rats. The 68 rats were divided into 4 groups with 17 rats in each group; PRP group (Week 2), control group (Week 2), PRP group (Week 4), and control group (Week 4). Platelet-rich plasma or saline was injected to the repair area intraoperatively. Rats were sacrificed 2 and 4 weeks after the surgery. Histological analysis using a semiquantitative scoring was performed on 7 rats per group. Tendon integrity and increases in vascularity and inflammatory cells and the degree of new bone formation were evaluated and compared between the groups. The remaining tendons (n=10) were mechanically tested. Degree of inflammation and vascularity were less in the study group at both time intervals (protator cuff tendon-to-bone healing and enhance initial tendon-to-bone healing remodeling. This may represent a clinically important improvement in rotator cuff repair.

  20. Differences in activation properties of the hamstring muscles during overground sprinting.

    Science.gov (United States)

    Higashihara, Ayako; Nagano, Yasuharu; Ono, Takashi; Fukubayashi, Toru

    2015-09-01

    The purpose of this study was to quantify activation of the biceps femoris (BF) and medial hamstring (MH) during overground sprinting. Lower-extremity kinematics and electromyography (EMG) of the BF and MH were recorded in 13 male sprinters performing overground sprinting at maximum effort. Mean EMG activity was calculated in the early stance, late stance, mid-swing, and late-swing phases. Activation of the BF was significantly greater during the early stance phase than the late stance phase (p<0.01). Activation of the BF muscle was significantly lower during the first half of the mid-swing phase than the other phases (p<0.05). The MH had significantly greater EMG activation relative to its recorded maximum values compared to that for the BF during the late stance (p<0.05) and mid-swing (p<0.01) phases. These results indicate that the BF shows high activation before and after foot contact, while the MH shows high activation during the late stance and mid-swing phases. We concluded that the activation properties of the BF and MH muscles differ within the sprinting gait cycle. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. The effect of anterior cruciate ligament reconstruction on hamstring and quadriceps muscle function outcome ratios in male athletes

    Directory of Open Access Journals (Sweden)

    Kadija Marko

    2016-01-01

    Full Text Available Introduction. Maximal strength ratios such as the limb symmetry index (LSI and hamstring-to-quadriceps ratio (HQ may be considered the main outcome measures in the monitoring of recovery after anterior cruciate ligament (ACL reconstruction. Although explosive strength is much more important than maximal strength, it is generally disregarded in the follow-up of muscle function recovery. Objective. The purpose of this study was to compare ratios between maximal (Fmax and explosive strength (rate of force development - RFD in individuals with ACL reconstruction. Methods. Fifteen male athletes were enrolled and had maximum voluntary isometric quadriceps and hamstring contractions tested (4.0 ± 0.1 months post reconstruction. In addition to Fmax, RFD was estimated (RFDmax, as well as RFD at 50, 100, and 200 ms from onset of contraction and LSI and HQ ratios were calculated. Results. The involved leg demonstrated significant hamstring and quadriceps deficits compared to uninvolved leg (p < 0.01. Deficits were particularly significant in the involved quadriceps, causing higher HQ ratios (average 0.63, compared to the uninvolved leg (0.44. LSI was significantly lower for RFD variables (average 55% than for Fmax (66%. Conclusion. The assessment of RFD may be considered an objective recovery parameter for one’s readiness to return to sports and should be an integral part of standard follow-up protocol for athletes after ACL reconstruction. Moreover, the combination of indices derived from maximal and explosive strength may provide better insight in muscle strength balance, as well as a clear picture of functional implications. [Projekat Ministarstva nauke Republike Srbije, br. 175012 i br. 175037

  2. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail

    2010-01-01

    PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (...... = 13) performed 3 days of treadmill running. Cellular proliferation was investigated 3 days before and 48 h after the running exercise with the use of FLT and positron emission tomography/computed tomography (PET/CT). Results were compared to a sedentary control group (n = 10). Image......-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue....

  3. Preventive effect of eccentric training on acute hamstring injuries in men's soccer: A cluster-randomized controlled trial

    DEFF Research Database (Denmark)

    Petersen, Jesper; Thorborg, Kristian; Nielsen, Michael Bachmann

    2011-01-01

    Background: The incidence of acute hamstring injuries is high in several sports, including the different forms of football. Purpose: The authors investigated the preventive effect of eccentric strengthening of the hamstring muscles using the Nordic hamstring exercise compared with no additional h...

  4. Oedema and fatty degeneration of the soleus and gastrocnemius muscles on MR images in patients with Achilles tendon abnormalities.

    Science.gov (United States)

    Hoffmann, Adrienne; Mamisch, Nadja; Buck, Florian M; Espinosa, Norman; Pfirrmann, Christian W A; Zanetti, Marco

    2011-09-01

    The purpose of this study was to evaluate the frequency of oedema and fatty degeneration of the soleus and gastrocnemius muscles in patients with Achilles tendon abnormalities. Forty-five consecutive patients (mean 51 years; range 14-84 years) with achillodynia were examined with magnetic resonance (MR) images of the calf. The frequency of oedema and fatty degeneration in the soleus and gastrocnemius muscles was determined in patients with normal tendons, tendinopathy and in patients with a partial tear or a complete tear of the Achilles tendon. Oedema was encountered in 35% (7/20) of the patients with tendinopathy (n = 20; range 13-81 years), and in 47% (9/19) of the patients with partial tears or complete tears (n = 19; 28-78 years). Fatty degeneration was encountered in 10% (2/20) of the patients with tendinopathy, and in 32% (6/19) of the patients with tears. The prevalence of fatty degeneration was significantly more common in patients with a partial or complete tear compared with the patients with a normal Achilles tendon (p = 0.032 and p = 0.021, respectively). Oedema and fatty degeneration of the soleus and gastrocnemius muscles are common in patients with Achilles tendon abnormalities.

  5. Gastrocnemius muscle contracture after spinal cord injury: a longitudinal study.

    Science.gov (United States)

    Diong, Joanna; Harvey, Lisa A; Kwah, Li Khim; Clarke, Jillian L; Bilston, Lynne E; Gandevia, Simon C; Herbert, Robert D

    2013-07-01

    The aim of this study was to examine changes in passive length and stiffness of the gastrocnemius muscle-tendon unit in people after spinal cord injury. In a prospective longitudinal study, eight wheelchair-dependent participants with severe paralysis were assessed 3 and 12 mos after spinal cord injury. Passive torque-angle data were obtained as the ankle was slowly rotated through range at six knee angles. Differences in passive ankle torque-angle data recorded at different knee angles were used to derive passive length-tension curves of the gastrocnemius muscle-tendon unit. Ultrasound imaging was used to determine fascicle and tendon contributions to the muscle-tendon unit length-tension curves. The participants had ankle contractures (mean [SD] maximum passive ankle dorsiflexion angle, 88 [9] degrees) 3 mos after spinal cord injury. Ankle range did not worsen significantly during the subsequent 9 mos (mean change, -5 degrees; 95% confidence interval, -16 to 6 degrees). There were no changes in the mean slack length or the stiffness of the gastrocnemius muscle-tendon unit or in the slack lengths of the fascicles or the tendon between 3 and 12 mos after spinal cord injury. There were no consistent patterns of the change in slack length or stiffness with the changes in ankle range in the data from the individual participants. This study, the first longitudinal study of muscle length and stiffness after spinal cord injury, showed that the length and the stiffness of the gastrocnemius did not change substantially between 3 and 12 mos after injury.

  6. Contributions of Hamstring Stiffness to Straight-Leg-Raise and Sit-and-Reach Test Scores.

    Science.gov (United States)

    Miyamoto, Naokazu; Hirata, Kosuke; Kimura, Noriko; Miyamoto-Mikami, Eri

    2018-02-01

    The passive straight-leg-raise (PSLR) and the sit-and-reach (SR) tests have been widely used to assess hamstring extensibility. However, it remains unclear to what extent hamstring stiffness (a measure of material properties) contributes to PSLR and SR test scores. Therefore, we aimed to clarify the relationship between hamstring stiffness and PSLR and SR scores using ultrasound shear wave elastography. Ninety-eight healthy subjects completed the study. Each subject completed PSLR testing, and classic and modified SR testing of the right leg. Muscle shear modulus of the biceps femoris, semitendinosus, and semimembranosus was quantified as an index of muscle stiffness. The relationships between shear modulus of each muscle and PSLR or SR scores were calculated using Pearson's product-moment correlation coefficients. Shear modulus of the semitendinosus and semimembranosus showed negative correlations with the two PSLR and two SR scores (absolute r value≤0.484). Shear modulus of the biceps femoris was significantly correlated with the PSLR score determined by the examiner and the modified SR score (absolute r value≤0.308). The present findings suggest that PSLR and SR test scores are strongly influenced by factors other than hamstring stiffness and therefore might not accurately evaluate hamstring stiffness. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Stretching skeletal muscle: chronic muscle lengthening through sarcomerogenesis.

    Directory of Open Access Journals (Sweden)

    Alexander M Zöllner

    Full Text Available Skeletal muscle responds to passive overstretch through sarcomerogenesis, the creation and serial deposition of new sarcomere units. Sarcomerogenesis is critical to muscle function: It gradually re-positions the muscle back into its optimal operating regime. Animal models of immobilization, limb lengthening, and tendon transfer have provided significant insight into muscle adaptation in vivo. Yet, to date, there is no mathematical model that allows us to predict how skeletal muscle adapts to mechanical stretch in silico. Here we propose a novel mechanistic model for chronic longitudinal muscle growth in response to passive mechanical stretch. We characterize growth through a single scalar-valued internal variable, the serial sarcomere number. Sarcomerogenesis, the evolution of this variable, is driven by the elastic mechanical stretch. To analyze realistic three-dimensional muscle geometries, we embed our model into a nonlinear finite element framework. In a chronic limb lengthening study with a muscle stretch of 1.14, the model predicts an acute sarcomere lengthening from 3.09[Formula: see text]m to 3.51[Formula: see text]m, and a chronic gradual return to the initial sarcomere length within two weeks. Compared to the experiment, the acute model error was 0.00% by design of the model; the chronic model error was 2.13%, which lies within the rage of the experimental standard deviation. Our model explains, from a mechanistic point of view, why gradual multi-step muscle lengthening is less invasive than single-step lengthening. It also explains regional variations in sarcomere length, shorter close to and longer away from the muscle-tendon interface. Once calibrated with a richer data set, our model may help surgeons to prevent muscle overstretch and make informed decisions about optimal stretch increments, stretch timing, and stretch amplitudes. We anticipate our study to open new avenues in orthopedic and reconstructive surgery and enhance

  8. Acute effects of static stretching on peak and end-range hamstring-to-quadriceps functional ratios

    Science.gov (United States)

    Sekir, Ufuk; Arabaci, Ramiz; Akova, Bedrettin

    2015-01-01

    AIM: To evaluate if static stretching influences peak and end-range functional hamstring-to-quadriceps (H/Q) strength ratios in elite women athletes. METHODS: Eleven healthy female athletes in an elite competitive level participated to the study. All the participants fulfilled the static stretching or non-stretching (control) intervention protocol in a randomized design on different days. Two static unassisted stretching exercises, one in standing and one in sitting position, were used to stretch both the hamstring and quadriceps muscles during these protocols. The total time for the static stretching was 6 ± 1 min. The isokinetic peak torque measurements for the hamstring and quadriceps muscles in eccentric and concentric modes and the calculations for the functional H/Q strength ratios at angular velocities of 60°/s and 180°/s were made before (pre) and after (post) the control or stretching intervention. The strength measurements and functional strength ratio calculations were based during the entire- and end-range of knee extension. RESULTS: The pre-test scores for quadriceps and hamstring peak torque and end range values were not significantly different between the groups (P > 0.05). Subsequently, although the control group did not exhibit significant changes in quadriceps and hamstring muscle strength (P > 0.05), static stretching decreased eccentric and concentric quadriceps muscle strength at both the 60°/s and 180°/s test speeds (P hamstring muscle strength at both the 60°/s and 180°/s test speeds (P 0.05). Furthermore, the functional H/Q strength ratios exhibited no significant alterations during the entire and end ranges of knee extension both in the static stretching or the control intervention (P > 0.05). CONCLUSION: According to our results, static stretching routine does not influence functional H/Q ratio. Athletes can confidently perform static stretching during their warm-up routines. PMID:26495249

  9. Proximal hamstring reconstruction using semitendinosus and gracilis autograft: a novel technique.

    Science.gov (United States)

    Muellner, Thomas; Kumar, Sandeep; Singla, Amit

    2017-01-01

    The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report. V.

  10. The interfascicular matrix enables fascicle sliding and recovery in tendon, and behaves more elastically in energy storing tendons.

    Science.gov (United States)

    Thorpe, Chavaunne T; Godinho, Marta S C; Riley, Graham P; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2015-12-01

    While the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the cost of locomotion. Energy storing tendons experience extremely high strains and need to be able to recoil efficiently for maximum energy storage and return. In the equine forelimb, the energy storing superficial digital flexor tendon (SDFT) has much higher failure strains than the positional common digital extensor tendon (CDET). However, we have previously shown that this is not due to differences in the properties of the SDFT and CDET fascicles (the largest tendon subunits). Instead, there is a greater capacity for interfascicular sliding in the SDFT which facilitates the greater extensions in this particular tendon (Thorpe et al., 2012). In the current study, we exposed fascicles and interfascicular matrix (IFM) from the SDFT and CDET to cyclic loading followed by a test to failure. The results show that IFM mechanical behaviour is not a result of irreversible deformation, but the IFM is able to withstand cyclic loading, and is more elastic in the SDFT than in the CDET. We also assessed the effect of ageing on IFM properties, demonstrating that the IFM is less able to resist repetitive loading as it ages, becoming stiffer with increasing age in the SDFT. These results provide further indications that the IFM is important for efficient function in energy storing tendons, and age-related alterations to the IFM may compromise function and predispose older tendons to injury. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Tendon synovial cells secrete fibronectin in vivo and in vitro

    International Nuclear Information System (INIS)

    Banes, A.J.; Link, G.W.; Bevin, A.G.; Peterson, H.D.; Gillespie, Y.; Bynum, D.; Watts, S.; Dahners, L.

    1988-01-01

    The chemistry and cell biology of the tendon have been largely overlooked due to the emphasis on collagen, the principle structural component of the tendon. The tendon must not only transmit the force of muscle contraction to bone to effect movement, but it must also glide simultaneously over extratendonous tissues. Fibronectin is classified as a cell attachment molecule that induces cell spreading and adhesion to substratum. The external surface of intact avian flexor tendon stained positively with antibody to cellular fibronectin. However, if the surface synovial cells were first removed with collagenase, no positive reaction with antifibronectin antibody was detected. Analysis of immunologically stained frozen sections of tendon also revealed fibronectin at the tendon synovium, but little was associated with cells internal in tendon. The staining pattern with isolated, cultured synovial cells and fibroblasts from the tendon interior substantiated the histological observations. Analysis of polyacrylamide gel profiles of 35 S-methionine-labeled proteins synthesized by synovial cells and internal fibroblasts indicated that fibronectin was synthesized principally by synovial cells. Fibronectin at the tendon surface may play a role in cell attachment to prevent cell removal by the friction of gliding. Alternatively, fibronectin, with its binding sites for hyaluronic acid and collagen, may act as a complex for boundary lubrication

  12. Ruptures of the pectoralis major muscle and it’s tendon: review of the literature and our experience in the treatment

    Directory of Open Access Journals (Sweden)

    G. M. Kavalersky

    2015-01-01

    Full Text Available Tendon ruptures of the pectoralis major muscle are considered a rare type of injury, but there is a tendency for a greater frequency of occurrence in such cases, which is associated with an increased interest in sport and fitness among the population. Despite the seeming simplicity of diagnosis, many complete ruptures remain unrecognized and many patients do not seek medical help or being treated for bruises, sprains and partial damage, although in fact there a complete ruptures of the pectoralis major muscle or it’s tendon. Currently there is no consensus on diagnostic tactics, surgical approach, the optimal method of fixation, indications for use of plastic material; disputable tactics of chronic ruptures and rehabilitation program in the treatment of tendon ruptures of the pectoralis major muscle.

  13. S-13: Interventions for Prevention and Rehabilitation of Hamstring Injuries

    Directory of Open Access Journals (Sweden)

    Reza Rahimi Moghaddam

    2017-03-01

    Full Text Available INTRODUCTION: The hamstring muscles have very important role in the stabilization of body posture, movement of the lower extremities and trunk movements in relation to the thigh. Hamstring injuries are common among athletes, especially in sports like soccer with sprinting demands, kicking, and sudden accelerations. Hamstring strains are frustrating for the injured athletes because the symptoms are persistent, healing is slow, and the rate of re-injury is high. This indicates a need to develop prevention strategies for hamstring injuries. The aims of this review are introducing hamstring strains, associated risk factors, and providing rehabilitative ecommendations for injured athletes to prevent re-injury. METHOD: Information was gathered from an online literatures search using the key words hamstring injuries, soccer injuries, injury prevention, hamstring rehabilitation, and stretching exercises. Screening of references and hand searches of relevant journals were also employed. All relevant studies in English were reviewed and abstracted.RESULTS: It has been shown that hamstring strains account for 12-16% of all injuries in athletes with a re-injury rate reported as high as 22-34%. The hamstrings have a tendency to shorten. Tight hamstrings with limited range of motion and flexibility may lead to postural deficiency and deformities. It also makes the hamstring susceptible to re-injury. Risk factors such as age, strength imbalance, previous injury and flexibility should be considered. CONCLUSION: Prevention intervention may minimize the risk factors of hamstring injuries. Training modalities should emphasize on eccentric strength training, and prevention of fatigue. There is wide disagreement about the impact of stretching exercise on prevention/rehabilitation of hamstring injuries.

  14. Gross and histological evaluation of early lesions of navicular bone and deep digital flexor tendon in horses

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    Komosa Marcin

    2014-03-01

    Full Text Available The study aimed at evaluation of pathological lesions on flexor surface of navicular bone and deep digital flexor tendon in horses graded in standard X-ray examination as 2 (fair. The evaluation was performed on fifteen horses (6-9 years of age. Analysis procedure involved examining navicular bones on X-ray pictures, post-slaughter preparation of navicular bones from the hoof capsule, macroscopic evaluation of fibrocartilage on flexor surface, and analysis of histologic preparations. In horses with navicular bones graded as 2, early pathological changes have already developed, even if such horses were not lame. The pathological changes included fibrillation and disruption of deep digital flexor tendon surface, loss of fibrocartillage in sagittal ridge area of navicular bone, thinning of subchondral bone on its flexor surface, and fibromyxoid changes in chondroid matrix. In terms of clinical relevance, more studies are needed to understand the sequence of changes in a better way.

  15. More is not always better: modeling the effects of elastic exoskeleton compliance on underlying ankle muscle-tendon dynamics.

    Science.gov (United States)

    Robertson, Benjamin D; Farris, Dominic J; Sawicki, Gregory S

    2014-11-24

    Development of robotic exoskeletons to assist/enhance human locomotor performance involves lengthy prototyping, testing, and analysis. This process is further convoluted by variability in limb/body morphology and preferred gait patterns between individuals. In an attempt to expedite this process, and establish a physiological basis for actuator prescription, we developed a simple, predictive model of human neuromechanical adaptation to a passive elastic exoskeleton applied at the ankle joint during a functional task. We modeled the human triceps surae-Achilles tendon muscle tendon unit (MTU) as a single Hill-type muscle, or contractile element (CE), and series tendon, or series elastic element (SEE). This modeled system was placed under gravitational load and underwent cyclic stimulation at a regular frequency (i.e. hopping) with and without exoskeleton (Exo) assistance. We explored the effect that both Exo stiffness (kExo) and muscle activation (Astim) had on combined MTU and Exo (MTU + Exo), MTU, and CE/SEE mechanics and energetics. Model accuracy was verified via qualitative and quantitative comparisons between modeled and prior experimental outcomes. We demonstrated that reduced Astim can be traded for increased kExo to maintain consistent MTU + Exo mechanics (i.e. average positive power (P⁺mech) output) from an unassisted condition (i.e. kExo = 0 kN · m⁻¹). For these regions of parameter space, our model predicted a reduction in MTU force, SEE energy cycling, and metabolic rate (Pmet), as well as constant CE P⁺mech output compared to unassisted conditions. This agreed with previous experimental observations, demonstrating our model's predictive ability. Model predictions also provided insight into mechanisms of metabolic cost minimization, and/or enhanced mechanical performance, and we concluded that both of these outcomes cannot be achieved simultaneously, and that one must come at the detriment of the other in a spring-assisted compliant MTU.

  16. Development of a subset of forelimb muscles and their attachment sites requires the ulnar-mammary syndrome gene Tbx3

    Directory of Open Access Journals (Sweden)

    Mary P. Colasanto

    2016-11-01

    Full Text Available In the vertebrate limb over 40 muscles are arranged in a precise pattern of attachment via muscle connective tissue and tendon to bone and provide an extensive range of motion. How the development of somite-derived muscle is coordinated with the development of lateral plate-derived muscle connective tissue, tendon and bone to assemble a functional limb musculoskeletal system is a long-standing question. Mutations in the T-box transcription factor, TBX3, have previously been identified as the genetic cause of ulnar-mammary syndrome (UMS, characterized by distinctive defects in posterior forelimb bones. Using conditional mutagenesis in mice, we now show that TBX3 has a broader role in limb musculoskeletal development. TBX3 is not only required for development of posterior forelimb bones (ulna and digits 4 and 5, but also for a subset of posterior muscles (lateral triceps and brachialis and their bone eminence attachment sites. TBX3 specification of origin and insertion sites appears to be tightly linked with whether these particular muscles develop and may represent a newly discovered mechanism for specification of anatomical muscles. Re-examination of an individual with UMS reveals similar previously unrecognized muscle and bone eminence defects and indicates a conserved role for TBX3 in regulating musculoskeletal development.

  17. Nonoperative, dynamic treatment of acute achilles tendon rupture

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner; Bencke, Jesper; Lauridsen, Hanne Bloch

    2015-01-01

    Acute Achilles tendon rupture alters the biomechanical properties of the plantar flexor muscle-tendon complex that can affect functional performance and the risk of repeat injury. The purpose of the present study was to compare the biomechanical properties of the plantar flexor muscle-tendon comp......Acute Achilles tendon rupture alters the biomechanical properties of the plantar flexor muscle-tendon complex that can affect functional performance and the risk of repeat injury. The purpose of the present study was to compare the biomechanical properties of the plantar flexor muscle...... in the terminal part of dorsiflexion was found in the non-weightbearing group. The altered stiffness and strength in the affected limb could affect the coordination of gait and running....

  18. Imbalances in the Development of Muscle and Tendon as Risk Factor for Tendinopathies in Youth Athletes: A Review of Current Evidence and Concepts of Prevention

    Directory of Open Access Journals (Sweden)

    Falk Mersmann

    2017-12-01

    Full Text Available Tendons feature the crucial role to transmit the forces exerted by the muscles to the skeleton. Thus, an increase of the force generating capacity of a muscle needs to go in line with a corresponding modulation of the mechanical properties of the associated tendon to avoid potential harm to the integrity of the tendinous tissue. However, as summarized in the present narrative review, muscle and tendon differ with regard to both the time course of adaptation to mechanical loading as well as the responsiveness to certain types of mechanical stimulation. Plyometric loading, for example, seems to be a more potent stimulus for muscle compared to tendon adaptation. In growing athletes, the increased levels of circulating sex hormones might additionally augment an imbalanced development of muscle strength and tendon mechanical properties, which could potentially relate to the increasing incidence of tendon overload injuries that has been indicated for adolescence. In fact, increased tendon stress and strain due to a non-uniform musculotendinous development has been observed recently in adolescent volleyball athletes, a high-risk group for tendinopathy. These findings highlight the importance to deepen the current understanding of the interaction of loading and maturation and demonstrate the need for the development of preventive strategies. Therefore, this review concludes with an evidence-based concept for a specific loading program for increasing tendon stiffness, which could be implemented in the training regimen of young athletes at risk for tendinopathy. This program incorporates five sets of four contractions with an intensity of 85–90% of the isometric voluntary maximum and a movement/contraction duration that provides 3 s of high magnitude tendon strain.

  19. Effect of growth hormone on aging connective tissue in muscle and tendon - gene expression, morphology and function following immobilization and rehabilitation

    DEFF Research Database (Denmark)

    Boesen, Anders Ploug; Dideriksen, Kasper Juel; Couppe, Christian

    2014-01-01

    assigned to daily injections of recombinant GH(rhGH, n=6) or placebo(Plc, n=6). Cross sectional area(CSA), muscle strength(MVC) and biomechanical properties of m. quadriceps and patellar tendon were determined. Muscle and tendon biopsies were analyzed for gene expressions (mRNA) of collagen(COL1A1/3A1...... pronounced when GH was injected. Furthermore, tendon stiffness increased in GH group. Muscle CSA declined after immobilization in Plc but not in GH group. Muscle CSA increased during re-training with a significant larger increase in GH group compared to Plc. Both a time and group effect was seen for IGF-1Ea....../Ec and COL1A1/3A1 mRNA expression in muscle with a difference between GH and Plc. IGF-1Ea/Ec and COL-1A1/3A1 mRNA expression increased in muscle following immobilization and re-training in subjects receiving GH, whereas an increase in IGF-1Ec mRNA expression was seen in the Plc group only after re...

  20. Adaptive Remodeling of Achilles Tendon: A Multi-scale Computational Model.

    Directory of Open Access Journals (Sweden)

    Stuart R Young

    2016-09-01

    Full Text Available While it is known that musculotendon units adapt to their load environments, there is only a limited understanding of tendon adaptation in vivo. Here we develop a computational model of tendon remodeling based on the premise that mechanical damage and tenocyte-mediated tendon damage and repair processes modify the distribution of its collagen fiber lengths. We explain how these processes enable the tendon to geometrically adapt to its load conditions. Based on known biological processes, mechanical and strain-dependent proteolytic fiber damage are incorporated into our tendon model. Using a stochastic model of fiber repair, it is assumed that mechanically damaged fibers are repaired longer, whereas proteolytically damaged fibers are repaired shorter, relative to their pre-damage length. To study adaptation of tendon properties to applied load, our model musculotendon unit is a simplified three-component Hill-type model of the human Achilles-soleus unit. Our model results demonstrate that the geometric equilibrium state of the Achilles tendon can coincide with minimization of the total metabolic cost of muscle activation. The proposed tendon model independently predicts rates of collagen fiber turnover that are in general agreement with in vivo experimental measurements. While the computational model here only represents a first step in a new approach to understanding the complex process of tendon remodeling in vivo, given these findings, it appears likely that the proposed framework may itself provide a useful theoretical foundation for developing valuable qualitative and quantitative insights into tendon physiology and pathology.

  1. Feasibility and reliability of using an exoskeleton to emulate muscle contractures during walking.

    Science.gov (United States)

    Attias, M; Bonnefoy-Mazure, A; De Coulon, G; Cheze, L; Armand, S

    2016-10-01

    Contracture is a permanent shortening of the muscle-tendon-ligament complex that limits joint mobility. Contracture is involved in many diseases (cerebral palsy, stroke, etc.) and can impair walking and other activities of daily living. The purpose of this study was to quantify the reliability of an exoskeleton designed to emulate lower limb muscle contractures unilaterally and bilaterally during walking. An exoskeleton was built according to the following design criteria: adjustable to different morphologies; respect of the principal lines of muscular actions; placement of reflective markers on anatomical landmarks; and the ability to replicate the contractures of eight muscles of the lower limb unilaterally and bilaterally (psoas, rectus femoris, hamstring, hip adductors, gastrocnemius, soleus, tibialis posterior, and peroneus). Sixteen combinations of contractures were emulated on the unilateral and bilateral muscles of nine healthy participants. Two sessions of gait analysis were performed at weekly intervals to assess the reliability of the emulated contractures. Discrete variables were extracted from the kinematics to analyse the reliability. The exoskeleton did not affect normal walking when contractures were not emulated. Kinematic reliability varied from poor to excellent depending on the targeted muscle. Reliability was good for the bilateral and unilateral gastrocnemius, soleus, and tibialis posterior as well as the bilateral hamstring and unilateral hip adductors. The exoskeleton can be used to replicate contracture on healthy participants. The exoskeleton will allow us to differentiate primary and compensatory effects of muscle contractures on gait kinematics. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Effects of electrical stimulation-induced gluteal versus gluteal and hamstring muscles activation on sitting pressure distribution in persons with a spinal cord injury

    NARCIS (Netherlands)

    Smit, C. A. J.; Haverkamp, G. L. G.; de Groot, S.; Stolwijk-Swuste, J. M.; Janssen, T. W. J.

    Study design: Ten participants underwent two electrical stimulation (ES) protocols applied using a custom-made electrode garment with built-in electrodes. Interface pressure was measured using a force-sensitive area. In one protocol, both the gluteal and hamstring (g+h) muscles were activated, in

  3. Tendon retraction with rotator cuff tear causes a decrease in cross-sectional area of the supraspinatus muscle on magnetic resonance imaging.

    Science.gov (United States)

    Fukuta, Shoji; Tsutsui, Takahiko; Amari, Rui; Wada, Keizo; Sairyo, Koichi

    2016-07-01

    Muscle atrophy and fatty degeneration of the rotator cuff muscles have been reported as negative prognostic indicators after rotator cuff repair. Although the Y-shaped view is widely used for measuring the cross-sectional area of the supraspinatus muscle, the contribution of retraction of the torn tendon as well as muscle atrophy must be considered. The purpose of this study was to clarify the relationship between cross-sectional area and tendon retraction or size of the tear. This study included 76 shoulders that were evaluated arthroscopically for the presence and size of tears. Cross-sectional areas of rotator cuff muscles were measured from the Y-shaped view to 3 more medial slices. The occupation ratio and tangent sign were evaluated on the Y-shaped view. The retraction of torn tendon was also measured on the oblique coronal images. On the Y-shaped view, the cross-sectional area of the supraspinatus and the occupation ratio decreased in conjunction with the increase in tear size. A significant decrease in cross-sectional area was noted only in large and massive tears on more medial slices from the Y-shaped view. Significant decreases in the cross-sectional area of the infraspinatus were observed in large and massive tears on all images. A negative correlation was found between tendon retraction and cross-sectional area, which was strongest on the Y-shaped view. To avoid the influence of retraction of the supraspinatus tendon, sufficient medial slices from the musculotendinous junction should be used for evaluation of muscle atrophy. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  4. Calf Muscle Performance Deficits Remain 7 Years After an Achilles Tendon Rupture.

    Science.gov (United States)

    Brorsson, Annelie; Grävare Silbernagel, Karin; Olsson, Nicklas; Nilsson Helander, Katarina

    2018-02-01

    Optimizing calf muscle performance seems to play an important role in minimizing impairments and symptoms after an Achilles tendon rupture (ATR). The literature lacks long-term follow-up studies after ATR that describe calf muscle performance over time. The primary aim was to evaluate calf muscle performance and patient-reported outcomes at a mean of 7 years after ATR in patients included in a prospective, randomized controlled trial. A secondary aim was to evaluate whether improvement in calf muscle performance continued after the 2-year follow-up. Cohort study; Level of evidence, 2. Sixty-six subjects (13 women, 53 men) with a mean age of 50 years (SD, 8.5 years) were evaluated at a mean of 7 years (SD, 1 year) years after their ATR. Thirty-four subjects had surgical treatment and 32 had nonsurgical treatment. Patient-reported outcomes were evaluated with Achilles tendon Total Rupture Score (ATRS) and Physical Activity Scale (PAS). Calf muscle performance was evaluated with single-leg standing heel-rise test, concentric strength power heel-rise test, and single-legged hop for distance. Limb Symmetry Index (LSI = injured side/healthy side × 100) was calculated for side-to-side differences. Seven years after ATR, the injured side showed decreased values in all calf muscle performance tests ( P performance did not continue after the 2-year follow-up. Heel-rise height increased significantly ( P = .002) between the 1-year (10.8 cm) and the 7-year (11.5 cm) follow-up assessments. The median ATRS was 96 (of a possible score of 100) and the median PAS was 4 (of a possible score of 6), indicating minor patient-reported symptoms and fairly high physical activity. No significant differences were found in calf muscle performance or patient-reported outcomes between the treatment groups except for the LSI for heel-rise repetitions. Continued deficits in calf muscle endurance and strength remained 7 years after ATR. No continued improvement in calf muscle performance

  5. Allogeneic versus autologous derived cell sources for use in engineered bone-ligament-bone grafts in sheep anterior cruciate ligament repair.

    Science.gov (United States)

    Mahalingam, Vasudevan D; Behbahani-Nejad, Nilofar; Horine, Storm V; Olsen, Tyler J; Smietana, Michael J; Wojtys, Edward M; Wellik, Deneen M; Arruda, Ellen M; Larkin, Lisa M

    2015-03-01

    The use of autografts versus allografts for anterior cruciate ligament (ACL) reconstruction is controversial. The current popular options for ACL reconstruction are patellar tendon or hamstring autografts, yet advances in allograft technologies have made allogeneic grafts a favorable option for repair tissue. Despite this, the mismatched biomechanical properties and risk of osteoarthritis resulting from the current graft technologies have prompted the investigation of new tissue sources for ACL reconstruction. Previous work by our lab has demonstrated that tissue-engineered bone-ligament-bone (BLB) constructs generated from an allogeneic cell source develop structural and functional properties similar to those of native ACL and vascular and neural structures that exceed those of autologous patellar tendon grafts. In this study, we investigated the effectiveness of our tissue-engineered ligament constructs fabricated from autologous versus allogeneic cell sources. Our preliminary results demonstrate that 6 months postimplantation, our tissue-engineered auto- and allogeneic BLB grafts show similar histological and mechanical outcomes indicating that the autologous grafts are a viable option for ACL reconstruction. These data indicate that our tissue-engineered autologous ligament graft could be used in clinical situations where immune rejection and disease transmission may preclude allograft use.

  6. STUDY TO COMPARE THE EFFECTIVENESS OF STATIC STRETCH AND HOLD RELAX TECHNIQUE OVER HAMSTRING FLEXIBILITY

    Directory of Open Access Journals (Sweden)

    Shanthi C

    2014-10-01

    Full Text Available Background: Numerous studies have documented on flexibility of muscles. Flexibility is defined as the ability of the muscles to lengthen allowing one joint or more than one joint in a series to move through a range of motion .Flexibility allows tissue to accommodate more easily to stress thus minimizing or preventing muscle injury. But this study sought to identify the study to compare the effectiveness of Static stretch and Hold relax technique over the hamstring flexibility. Methods: 30 healthy male adults with Hamstring tightness aged 21 to 35 years selected from general population through simple randomized technique. Samples are divided into two groups, static stretch Group-I(no.15 and Group-II Hold relax (no.=15.The outcome was measured with help of sit & reach test to see the Hamstring flexibility. Results: Comparison of the post test values of the group I and group II shows a significant difference between the outcomes of two groups with a “t” calculated value of 0.738 (unpaired “t” test. Conclusion: Both static stretch and hold relax Technique can cause very highly significant result in Hamstring Flexibility, further comparison shows very high significant difference between two groups and concludes that hold relax is better than static stretch in Hamstring Flexibility.

  7. Anterior cruciate ligament reconstruction with tibial attachment preserving hamstring graft without implant on tibial side

    Directory of Open Access Journals (Sweden)

    Skand Sinha

    2018-01-01

    Full Text Available Background: Tibial attachment preserving hamstring graft could prevent potential problems of free graft in anterior cruciate ligament (ACL reconstruction such as pull out before graft-tunnel healing or rupture before ligamentization. Different implants have been reportedly used for tibial side fixation with this technique. We investigated short-term outcome of ACL reconstruction (ACLR with tibial attachment sparing hamstring graft without implant on the tibial side by outside in technique. Materials and Methods: Seventy nine consecutive cases of ACL tear having age of 25.7 ± 6.8 years were included after Institutional Board Approval. All subjects were male. The mean time interval from injury to surgery was of 7.5 ± 6.4 months. Hamstring tendons were harvested with open tendon stripper leaving the tibial insertion intact. The free ends of the tendons were whip stitched, quadrupled, and whip stitched again over the insertion site of hamstring with fiber wire (Arthrex. Single bundle ACLR was done by outside in technique and the femoral tunnel was created with cannulated reamer. The graft was pulled up to the external aperture of femoral tunnel and fixed with interference screw (Arthrex. The scoring was done by Lysholm, Tegner, and KT 1000 by independent observers. All cases were followed up for 2 years. Results: The mean length of quadrupled graft attached to tibia was 127.65 ± 7.5 mm, and the mean width was 7.52 ± 0.78 mm. The mean preoperative Lysholm score of 47.15 ± 9.6, improved to 96.8 ± 2.4 at 1 year. All cases except two returned to the previous level of activity after ACLR. There was no significant difference statistically between preinjury (5.89 ± 0.68 and postoperative (5.87 ± 0.67 Tegner score. The anterior tibial translation (ATT (KT 1000 improved from 11.44 ± 1.93 mm to 3.59 ± 0.89 mm. The ATT of operated knee returned to nearly the similar value as of the opposite knee (3.47 ± 1.16 mm. The Pivot shift test was negative in

  8. Muscle cramps

    Science.gov (United States)

    ... the lower leg/calf Back of the thigh (hamstrings) Front of the thigh (quadriceps) Cramps in the ... Names Cramps - muscle Images Chest stretch Groin stretch Hamstring stretch Hip stretch Thigh stretch Triceps stretch References ...

  9. Variation in the insertion of the palmaris longus tendon

    Science.gov (United States)

    Sunil, Vinutha; Rajanna, Shubha; Gitanjali; Kadaba, Jayanthi

    2015-01-01

    The palmaris longus is harvested as a tendon graft in various surgical procedures. We herein report the variations in the insertion of the palmaris longus tendon. During a routine dissection, a rare variation in the insertion of the palmaris longus tendon was observed. In the left forearm, the palmaris longus tendon bifurcated, while in the right forearm, the palmaris longus tendon trifurcated, giving rise to an accessory muscle, which passed superficial to the ulnar artery and ulnar nerve. The accessory muscle was supplied by a deep branch of the ulnar nerve, and the ulnar artery was observed to be tortuous. During reconstructive surgeries, surgeons should bear in mind the accessory muscle. Also, since the palmaris longus muscle provides a very useful graft in tendon surgery, every surgeon should be aware of the variations in the insertion of the palmaris longus tendon. PMID:25640108

  10. Effect of Knee Orthoses on Hamstring Contracture in Children With Cerebral Palsy: Multiple Single-Subject Study.

    Science.gov (United States)

    Laessker-Alkema, Kristina; Eek, Meta Nyström

    2016-01-01

    To examine the effect of knee orthoses on extensibility of the hamstrings in children with spastic cerebral palsy (CP). The short-term effects of knee orthoses on passive range of motion (ROM), spasticity, and gross motor function of the hamstrings. Ten children with spastic CP, aged 5 to 14 years, at Gross Motor Function Classification System levels I to V, were followed. The orthoses were worn for a minimum of 30 minutes day, 5 days per week, during the intervention period of 8 weeks. Visual analysis using the Two Standard Deviation Band Method supported improvements in passive ROM for all 20 hamstring muscles and in 12 of 14 knee extension measurements. Analyses with the Wilcoxon signed rank test confirm the individual results and support a significant increase in hamstring muscles (P = .005) and knee extension (right: P =.028; left: P =.018) compared with baseline. In children with spastic CP, 8 weeks of treatment with knee orthoses can improve extensibility of the hamstrings.

  11. Anatomical variation of radial wrist extensor muscles: a study in cadavers

    Directory of Open Access Journals (Sweden)

    Soubhagya Ranjan Nayak

    2008-01-01

    Full Text Available OBJECTIVE: The tendons of the extensor carpi radialis longus and brevis muscles are quite useful in tendon transfer, such as in correction of finger clawing and restoration of thumb opposition. Knowledge of additional radial wrist extensor muscle bellies with independent tendons is useful in the above-mentioned surgical procedures. METHODS: The skin, subcutaneous tissue, and antebrachial fascia of 48 (24 on the right side and 24 on left side male upper limb forearms were dissected. The following aspects were then analyzed: (a the presence of additional muscle bellies of radial wrist extensors, (b the origin and insertion of the additional muscle, and (c measurements of the muscle bellies and their tendons. RESULTS: Five out of 48 upper limbs (10.41% had additional radial wrist extensors; this occurred in 3 out of 24 left upper limbs (12.5% and 2 out of 24 right upper limbs (8.3%. In one of the right upper limbs, two additional muscles were found. The length and width of each additional muscle belly and its tendon ranged between 2 - 15cm by 0.35 - 6.4cm and 2.8 - 20.8cm by 0.2 0.5cm, respectively. The additional radial wrist extensor tendons in our study basically originated either from the extensor carpi radialis longus or brevis muscles and were inserted at the base of the 2nd or 3rd metacarpal bone. CONCLUSION: The present study will inform surgeons about the different varieties of additional radial wrist extensors and the frequency of their occurrence.

  12. The preventive effect of the bounding exercise programme on hamstring injuries in amateur soccer players : The design of a randomized controlled trial

    NARCIS (Netherlands)

    Van de Hoef, S.; Huisstede, B. M. A.; Brink, M. S.; de Vries, N.; Goedhart, E. A.; Backx, F. J. G.

    2017-01-01

    Background: Hamstring injuries are the most common muscle injury in amateur and professional soccer. Most hamstring injuries occur in the late swing phase, when the hamstring undergoes a stretch-shortening cycle and the hamstring does a significant amount of eccentric work. The incidence of these

  13. A model of the human triceps surae muscle-tendon complex applied to jumping

    NARCIS (Netherlands)

    Bobbert, Maarten F.; Huijing, Peter A.; van Ingen Schenau, Gerrit Jan

    1986-01-01

    The purpose of this study was to gain more insight into the behavior of the muscle-tendon complex of human m. triceps surae in jumping. During one-legged vertical jumps of ten subjects ground reaction forces as well as cinematographic data were registered, and electromyograms were recorded from m.

  14. Hamstring and Quadriceps Isokinetic Strength Deficits Are Weak Risk Factors for Hamstring Strain Injuries: A 4-Year Cohort Study

    NARCIS (Netherlands)

    van Dyk, Nicol; Bahr, Roald; Whiteley, Rodney; Tol, Johannes L.; Kumar, Bhavesh D.; Hamilton, Bruce; Farooq, Abdulaziz; Witvrouw, Erik

    2016-01-01

    A hamstring strain injury (HSI) has become the most common noncontact injury in soccer. Isokinetic muscle strength deficits are considered a risk factor for HSIs. However, underpowered studies with small sample sizes unable to determine small associations have led to inconclusive results regarding

  15. The eccentric, concentric strength relationship of the hamstring muscles in chronic low back pain.

    Science.gov (United States)

    Marshall, Paul W M; Mannion, Jamie; Murphy, Bernadette A

    2010-02-01

    The objective of this study was to measure hamstring muscle eccentric and concentric strength in individuals with and without low back pain (LBP). Two composite scores for the relative balance of eccentric to concentric strength at the different movement velocities were calculated (the DEC and SEC), to determine whether or not self perceived pain, disability, or fear avoidance measures were associated with hamstring strength characteristics. Cross-sectional repeated measures design. University laboratory. Fifteen individuals with chronic LBP and 15 matched controls. Isokinetic eccentric and concentric strength at 30 degrees s(-1) and 120 degrees s(-1)(.) Composite scores (DEC and SEC) based on peak torque were calculated to evaluate the relationship between the different muscle actions across the test velocities. Self report measures included the Oswestry disability index, general health and well being, fear avoidance, and pain. Eccentric/concentric strength ratio at 30 degrees s(-1) was higher for the LBP group (F(1,58)=4.81, p=0.032). The SEC was also higher for the LBP (F(1,58)=5.97, p=0.018). Fear avoidance beliefs and mental well-being were significantly associated with the SEC only in the LBP group (adjusted r(2)=0.26, (F(2,27)=5.8, p=.008). For the control group both the DEC and SEC were associated with self report measures. Matched differences between groups' for the SEC were best explained by fear avoidance beliefs about work (adjusted r(2)=0.12, F(1,28)=5.1, p=0.03). Reduced concentric relative to eccentric strength is best identified by the SEC. The SEC was significantly associated with impaired self report measures of fear avoidance and mental well being in individuals with LBP. Differences between groups for the SEC were best explained by fear avoidance beliefs about work.

  16. Expression of extracellular matrix components and related growth factors in human tendon and muscle after acute exercise

    DEFF Research Database (Denmark)

    Heinemeier, K M; Bjerrum, S S; Schjerling, P

    2013-01-01

    Acute kicking exercise induces collagen synthesis in both tendon and muscle in humans, but it is not known if this relates to increased collagen transcription and if other matrix genes are regulated. Young men performed 1 h of one-leg kicking at 67% of max workload. Biopsies were taken from...... the patellar tendon and vastus lateralis muscle of each leg at 2 (n = 10), 6 (n = 11), or 26 h (n = 10) after exercise. Levels of messenger ribonucleic acid mRNA for collagens, noncollagenous matrix proteins, and growth factors were measured with real-time reverse transcription polymerase chain reaction...

  17. Quantification of Internal Stress-Strain Fields in Human Tendon: Unraveling the Mechanisms that Underlie Regional Tendon Adaptations and Mal-Adaptations to Mechanical Loading and the Effectiveness of Therapeutic Eccentric Exercise

    Science.gov (United States)

    Maganaris, Constantinos N.; Chatzistergos, Panagiotis; Reeves, Neil D.; Narici, Marco V.

    2017-01-01

    By virtue of their anatomical location between muscles and bones, tendons make it possible to transform contractile force to joint rotation and locomotion. However, tendons do not behave as rigid links, but exhibit viscoelastic tensile properties, thereby affecting the length and contractile force in the in-series muscle, but also storing and releasing elastic stain energy as some tendons are stretched and recoiled in a cyclic manner during locomotion. In the late 90s, advancements were made in the application of ultrasound scanning that allowed quantifying the tensile deformability and mechanical properties of human tendons in vivo. Since then, the main principles of the ultrasound-based method have been applied by numerous research groups throughout the world and showed that tendons increase their tensile stiffness in response to exercise training and chronic mechanical loading, in general, by increasing their size and improving their intrinsic material. It is often assumed that these changes occur homogenously, in the entire body of the tendon, but recent findings indicate that the adaptations may in fact take place in some but not all tendon regions. The present review focuses on these regional adaptability features and highlights two paradigms where they are particularly evident: (a) Chronic mechanical loading in healthy tendons, and (b) tendinopathy. In the former loading paradigm, local tendon adaptations indicate that certain regions may “see,” and therefore adapt to, increased levels of stress. In the latter paradigm, local pathological features indicate that certain tendon regions may be “stress-shielded” and degenerate over time. Eccentric exercise protocols have successfully been used in the management of tendinopathy, without much sound understanding of the mechanisms underpinning their effectiveness. For insertional tendinopathy, in particular, it is possible that the effectiveness of a loading/rehabilitation protocol depends on the topography

  18. Measurement of Gender Differences of Gastrocnemius Muscle and Tendon Using Sonomyography during Calf Raises: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Guang-Quan Zhou

    2017-01-01

    Full Text Available Skeletal muscles are essential to the gender-specific characteristics of human movements. Sonomyography, a new signal for quantifying muscle activation, is of great benefit to understand muscle function through monitoring the real-time muscle architectural changes. The purpose of this pilot study was to investigate gender differences in the architectural changes of gastronomies muscle and tendon by using sonomyography during performing two-legged calf raising exercises. A motion analysis system was developed to extract sonomyography from ultrasound images together with kinematic and kinetic measurements. Tiny fascicle length changes among seven male subjects were observed at the initial part of calf raising, whereas the fascicle of seven female subjects shortened immediately. This result suggested that men would generate higher mechanical power output of plantar flexors to regulate their heavier body mass. In addition, the larger regression coefficient between the fascicle length and muscle force for the male subjects implied that higher muscle stiffness for the men was required in demand of maintaining their heavier body economically. The findings from the current study suggested that the body mass might play a factor in the gender difference in structural changes of muscle and tendon during motion. The sonomyography may provide valuable information in the understanding of the gender difference in human movements.

  19. Rehabilitation and return to sport after hamstring strain injury

    Directory of Open Access Journals (Sweden)

    Lauren N. Erickson

    2017-09-01

    Full Text Available Hamstring strain injuries are common among sports that involve sprinting, kicking, and high-speed skilled movements or extensive muscle lengthening-type maneuvers with hip flexion and knee extension. These injuries present the challenge of significant recovery time and a lengthy period of increased susceptibility for recurrent injury. Nearly one third of hamstring strains recur within the first year following return to sport with subsequent injuries often being more severe than the original. This high re-injury rate suggests that athletes may be returning to sport prematurely due to inadequate return to sport criteria. In this review article, we describe the epidemiology, risk factors, differential diagnosis, and prognosis of an acute hamstring strain. Based on the current available evidence, we then propose a clinical guide for the rehabilitation of acute hamstring strains and an algorithm to assist clinicians in the decision-making process when assessing readiness of an athlete to return to sport.

  20. Kinesthetic perception based on integration of motor imagery and afferent inputs from antagonistic muscles with tendon vibration.

    Science.gov (United States)

    Shibata, E; Kaneko, F

    2013-04-29

    The perceptual integration of afferent inputs from two antagonistic muscles, or the perceptual integration of afferent input and motor imagery are related to the generation of a kinesthetic sensation. However, it has not been clarified how, or indeed whether, a kinesthetic perception would be generated by motor imagery if afferent inputs from two antagonistic muscles were simultaneously induced by tendon vibration. The purpose of this study was to investigate how a kinesthetic perception would be generated by motor imagery during co-vibration of the two antagonistic muscles at the same frequency. Healthy subjects participated in this experiment. Illusory movement was evoked by tendon vibration. Next, the subjects imaged wrist flexion movement simultaneously with tendon vibration. Wrist flexor and extensor muscles were vibrated according to 4 patterns such that the difference between the two vibration frequencies was zero. After each trial, the perceived movement sensations were quantified on the basis of the velocity and direction of the ipsilateral hand-tracking movements. When the difference in frequency applied to the wrist flexor and the extensor was 0Hz, no subjects perceived movements without motor imagery. However, during motor imagery, the flexion velocity of the perceived movement was higher than the flexion velocity without motor imagery. This study clarified that the afferent inputs from the muscle spindle interact with motor imagery, to evoke a kinesthetic perception, even when the difference in frequency applied to the wrist flexor and extensor was 0Hz. Furthermore, the kinesthetic perception resulting from integrations of vibration and motor imagery increased depending on the vibration frequency to the two antagonistic muscles. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Effects of whole-body cryotherapy on recovery after hamstring damaging exercise

    OpenAIRE

    Fonda, Borut; Šarabon, Nejc

    2013-01-01

    The purpose of this study was to examine the effects of whole-body cryotherapy (WBC) on biochemical, pain, and performance parameters during the 5-day recovery period after damaging exercise for hamstrings. Participants completed a bout of damaging exercise for the hamstring muscles on two separate occasions (control and experimental condition) separated by 10 weeks. During the control condition, subjects received no treatment after the damaging exercise. The experimental condition consisted ...

  2. Bone Marrow Stromal Cells Generate Muscle Cells and Repair Muscle Degeneration

    Science.gov (United States)

    Dezawa, Mari; Ishikawa, Hiroto; Itokazu, Yutaka; Yoshihara, Tomoyuki; Hoshino, Mikio; Takeda, Shin-ichi; Ide, Chizuka; Nabeshima, Yo-ichi

    2005-07-01

    Bone marrow stromal cells (MSCs) have great potential as therapeutic agents. We report a method for inducing skeletal muscle lineage cells from human and rat general adherent MSCs with an efficiency of 89%. Induced cells differentiated into muscle fibers upon transplantation into degenerated muscles of rats and mdx-nude mice. The induced population contained Pax7-positive cells that contributed to subsequent regeneration of muscle upon repetitive damage without additional transplantation of cells. These MSCs represent a more ready supply of myogenic cells than do the rare myogenic stem cells normally found in muscle and bone marrow.

  3. The correlation between the imaging characteristics of hamstring injury and time required before returning to sports: a literature review.

    Science.gov (United States)

    Svensson, Kjell; Alricsson, Marie; Eckerman, Mattias; Magounakis, Theofilos; Werner, Suzanne

    2016-06-01

    Injuries to the hamstring muscles are common in athletes. Track and field, Australian football, American football and soccer are examples of sports where hamstring injuries are the most common. The purpose of this study was to investigate whether there is a correlation between a hamstring injury prognosis and its characteristics of imaging parameters. The literature search was performed in the databases PubMed and CINAHL, and eleven articles were included. Seven out of the 11 articles showed a correlation between the size of the hamstring injury and length of time required before returning to sports. Different authors have reported contrasting results about length of time required before returning to sports due to location of injury within specific muscle. Majority of the articles found hamstring strain correlated to an extended amount of time required before returning to sports.

  4. Effect of Platelet-Rich Plasma and Bioactive Glass Powder for the Improvement of Rotator Cuff Tendon-to-Bone Healing in a Rabbit Model

    Directory of Open Access Journals (Sweden)

    Yang Wu

    2014-11-01

    Full Text Available To test the hypothesis that a platelet-rich plasma (PRP plus bioactive glass (BG mixture could shorten the tendon-bone healing process in rotator cuff tendon repair, thirty mature male New Zealand white rabbits were randomly divided into three groups, Control, PRP, and PRP + BG. All groups underwent a surgical procedure to establish a rotator cuff tendon healing model. Mechanical examinations and histological assays were taken to verify the adhesion of the tendon-bone. Real-time PCR was adopted to analyze Bone Morphogenetic Protein-2 (BMP-2. The maximum load-to-failure value in mechanical examinations was significantly higher in the PRP + BG group than that in the control group after six weeks (Control 38.73 ± 8.58, PRP 54.49 ± 8.72, PRP + BG 79.15 ± 7.62, p < 0.001, but it was not significantly different at 12 weeks (PRP 74.27 ± 7.74, PRP + BG 82.57 ± 6.63, p = 0.145. In histological assays, H&E (hematoxylin-eosin staining showed that the interface between the tendon-bone integration was much sturdier in the PRP + BG group compared to the other two groups at each time point, and more ordered arranged tendon fibers can be seen at 12 weeks. At six weeks, the mRNA expression levels of BMP-2 in the PRP + BG group were higher than those in the other groups (PRP + BG 0.65 ± 0.11, PRP 2.284 ± 0.07, Control 0.12 ± 0.05, p < 0.05. However, there was no significant difference in the mRNA expression levels of BMP-2 among the three groups at 12 weeks (p = 0.922, 0.067, 0.056. BMP-2 levels in PRP and PRP+BG groups were significantly lower at 12 weeks compared to six weeks (p = 0.006, <0.001.We found that the PRP + BG mixture could enhance tendon-bone healing in rotator cuff tendon repair.

  5. No Relationship between Hamstring Flexibility and Hamstring Injuries in Male Amateur Soccer Players

    NARCIS (Netherlands)

    Van Doormaal, Mitchell C M; Van Der Horst, Nick; Backx, Frank J G; Smits, Dirk Wouter; Huisstede, Bionka M A

    2017-01-01

    BACKGROUND: In soccer, although hamstring flexibility is thought to play a major role in preventing hamstring injuries, the relationship between hamstring flexibility and hamstring injuries remains unclear. PURPOSE: To investigate the relationship between hamstring flexibility and hamstring injuries

  6. Knee and Hip Joint Kinematics Predict Quadriceps and Hamstrings Neuromuscular Activation Patterns in Drop Jump Landings.

    Science.gov (United States)

    Malfait, Bart; Dingenen, Bart; Smeets, Annemie; Staes, Filip; Pataky, Todd; Robinson, Mark A; Vanrenterghem, Jos; Verschueren, Sabine

    2016-01-01

    The purpose was to assess if variation in sagittal plane landing kinematics is associated with variation in neuromuscular activation patterns of the quadriceps-hamstrings muscle groups during drop vertical jumps (DVJ). Fifty female athletes performed three DVJ. The relationship between peak knee and hip flexion angles and the amplitude of four EMG vectors was investigated with trajectory-level canonical correlation analyses over the entire time period of the landing phase. EMG vectors consisted of the {vastus medialis(VM),vastus lateralis(VL)}, {vastus medialis(VM),hamstring medialis(HM)}, {hamstring medialis(HM),hamstring lateralis(HL)} and the {vastus lateralis(VL),hamstring lateralis(HL)}. To estimate the contribution of each individual muscle, linear regressions were also conducted using one-dimensional statistical parametric mapping. The peak knee flexion angle was significantly positively associated with the amplitudes of the {VM,HM} and {HM,HL} during the preparatory and initial contact phase and with the {VL,HL} vector during the peak loading phase (phamstrings medialis activity) during the preparatory and initial contact phase and an increased lateral neuromuscular activation (dominant vastus lateralis activity) during the peak loading phase.

  7. Impact of the Nordic hamstring and hip extension exercises on hamstring architecture and morphology: implications for injury prevention.

    Science.gov (United States)

    Bourne, Matthew N; Duhig, Steven J; Timmins, Ryan G; Williams, Morgan D; Opar, David A; Al Najjar, Aiman; Kerr, Graham K; Shield, Anthony J

    2017-03-01

    The architectural and morphological adaptations of the hamstrings in response to training with different exercises have not been explored. To evaluate changes in biceps femoris long head (BF LH ) fascicle length and hamstring muscle size following 10-weeks of Nordic hamstring exercise (NHE) or hip extension (HE) training. 30 recreationally active male athletes (age, 22.0±3.6 years; height, 180.4±7 cm; weight, 80.8±11.1 kg) were allocated to 1 of 3 groups: (1) HE training (n=10), NHE training (n=10), or no training (control, CON) (n=10). BF LH fascicle length was assessed before, during (Week 5) and after the intervention with a two-dimensional ultrasound. Hamstring muscle size was determined before and after training via MRI. Compared with baseline , BF LH fascicles were lengthened in the NHE and HE groups at mid-training (d=1.12-1.39, p<0.001) and post-training (d=1.77-2.17, p<0.001) and these changes did not differ significantly between exercises (d=0.49-0.80, p=0.279-0.976). BF LH volume increased more for the HE than the NHE (d=1.03, p=0.037) and CON (d=2.24, p<0.001) groups. Compared with the CON group, both exercises induced significant increases in semitendinosus volume (d=2.16-2.50, ≤0.002) and these increases were not significantly different (d=0.69, p=0.239). NHE and HE training both stimulate significant increases in BF LH fascicle length; however, HE training may be more effective for promoting hypertrophy in the BF LH . Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. The Effects of Cupping on Hamstring Flexibility in Collegiate Soccer Players.

    Science.gov (United States)

    Williams, Jeffrey G; Gard, Hannah I; Gregory, Jeana M; Gibson, Amy; Austin, Jennifer

    2018-01-24

    Collegiate soccer players suffer hamstring injuries due to inflexibility and repetitive motions involving intense hamstring lengthening and contraction during sport. Although a popular intervention for muscular injury, there exists limited evidence of the effects of therapeutic cupping on hamstring flexibility. To determine the effect of cupping therapy on hamstring flexibility in collegiate soccer players. Cohort design. Athletic training clinic. Twenty-five, asymptomatic, NCAA Division III soccer players (10 males, 15 females) (age = 19.4 ± 1.30 years, height = 175.1 ± 8.2 cm, mass = 69.5 ± 6.6 kg). A 7-minute therapeutic cupping treatment was delivered to the treatment group. Four 2-inch cups were fixed atop trigger point locations within the hamstring muscle bellies of participants' dominant legs. Control group participants received no intervention between pre- and post-test measurements. Pretest and posttest measurements of hamstring flexibility, using a Passive Straight Leg Raise (PSLR), were performed on both groups. PSLR measurements were conducted by blinded examiners using a digital inclinometer. An independent samples t-test was used to analyze changes in hamstring flexibility from pre- to post-treatment with p-values set a priori at 0.05. An independent samples t-test demonstrated no significant difference in change in hamstring flexibility between participants in the treatment group and those in the control group (t 23 = -.961, p = .35). The findings of this study demonstrated no statistically significant changes in hamstring flexibility following a cupping treatment.

  9. Piezoelectricity and absorption of water in biomaterials: bone and tendon

    International Nuclear Information System (INIS)

    Ghilardi Netto, T.

    1973-01-01

    A new application of the Fabry-Perot interferometer has been developed, capable of measuring variations in length with a precision of the order of one angstrom. The method has been applied to the determination of some of the inverse piezoelectric coefficients of bovine bone and tendon. The effect of water in these materials was carefully measured and shown to decrease the piezoelectricity. Correlations between the piezoelectricity and length, weight, and volume and surface resistivity were made during the absorption of water [pt

  10. The Improvement of Bone-Tendon Fixation by Porous Titanium Interference Screw: A Rabbit Animal Model.

    Science.gov (United States)

    Tsai, Pei-I; Chen, Chih-Yu; Huang, Shu-Wei; Yang, Kuo-Yi; Lin, Tzu-Hung; Chen, San-Yuan; Sun, Jui-Sheng

    2018-05-04

    The interference screw is a widely used fixation device in the anterior cruciate ligament (ACL) reconstruction surgeries. Despite the generally satisfactory results, problems of using interference screws were reported. By using additive manufacturing (AM) technology, we developed an innovative titanium alloy (Ti 6 Al 4 V) interference screw with rough surface and inter-connected porous structure designs to improve the bone-tendon fixation. An innovative Ti 6 Al 4 V interference screws were manufactured by AM technology. In vitro mechanical tests were performed to validate its mechanical properties. Twenty-seven New Zealand white rabbits were randomly divided into control and AM screw groups for biomechanical analyses and histological analysis at 4, 8 and 12 weeks postoperatively; while micro-CT analysis was performed at 12 weeks postoperatively. The biomechanical tests showed that the ultimate failure load in the AM interference screw group was significantly higher than that in the control group at all tested periods. These results were also compatible with the findings of micro-CT and histological analyses. In micro-CT analysis, the bone-screw gap was larger in the control group; while for the additive manufactured screw, the screw and bone growth was in close contact. In histological study, the bone-screw gaps were wider in the control group and were almost invisible in the AM screw group. The innovative AM interference screws with surface roughness and inter-connected porous architectures demonstrated better bone-tendon-implant integration, and resulted in stronger biomechanical characteristics when compared to traditional screws. These advantages can be transferred to future interference screw designs to improve their clinical performance. The AM interference screw could improve graft fixation and eventually result in better biomechanical performance of the bone-tendon-screw construct. The innovative AM interference screws can be transferred to future

  11. Diagnosing Snapping Sartorius Tendon Secondary to a Meniscal Cyst Using Dynamic Ultrasound Avoids Incorrect Surgical Procedure

    Directory of Open Access Journals (Sweden)

    Vipin Asopa

    2013-01-01

    Full Text Available We describe a case of painful snapping in the medial aspect of the knee of a 40-year-old man, following a knee hyperflexion injury. Dynamic real-time ultrasonography determined that the snapping was due to the distal tendon of sartorius passing over a medial meniscal cyst. The patient subsequently underwent arthroscopic decompression of the cyst instead of an inappropriate hamstring tendon harvest procedure, with complete resolution of symptoms.

  12. Tenomodulin is Required for Tendon Endurance Running and Collagen I Fibril Adaptation to Mechanical Load

    Directory of Open Access Journals (Sweden)

    Sarah Dex

    2017-06-01

    Full Text Available Tendons are dense connective tissues that attach muscles to bone with an indispensable role in locomotion because of their intrinsic properties of storing and releasing muscle- generated elastic energy. Tenomodulin (Tnmd is a well-accepted gene marker for the mature tendon/ligament lineage and its loss-of -function in mice leads to a phenotype with distinct signs of premature aging on tissue and stem/progenitor cell levels. Based on these findings, we hypothesized that Tnmd might be an important factor in the functional performance of tendons. Firstly, we revealed that Tnmd is a mechanosensitive gene and that the C-terminus of the protein co-localize with collagen I-type fibers in the extracellular matrix. Secondly, using an endurance training protocol, we compared Tnmd knockout mice with wild types and showed that Tnmd deficiency leads to significantly inferior running performance that further worsens with training. In these mice, endurance running was hindered due to abnormal response of collagen I cross-linking and proteoglycan genes leading to an inadequate collagen I fiber thickness and elasticity. In sum, our study demonstrates that Tnmd is required for proper tendon tissue adaptation to endurance running and aids in better understanding of the structural-functional relationships of tendon tissues.

  13. In vitro investigation of a tissue-engineered cell-tendon complex mimicking the transitional architecture at the ligament-bone interface.

    Science.gov (United States)

    Wang, Zhibing; Zhang, Yuan; Zhu, Jie; Dong, Shiwu; Jiang, Tao; Zhou, Yue; Zhang, Xia

    2015-03-01

    Restoration of the transitional ligament-bone interface is critical for graft-bone integration. We postulated that an allogenic scaffold mimicking the fibrogenic, chondrogenic, and osteogenic transition gradients could physiologically promote ligament-bone incorporation. The aim of this study was to construct and characterize a composite tendon scaffold with a continuous and heterogeneous transition region mimicking a native ligament insertion site. Genetically modified heterogeneous cell populations were seeded within specific regions of decellularized rabbit Achilles tendons to fabricate a stratified scaffold containing three biofunctional regions supporting fibrogenesis, chondrogenesis, and osteogenesis. The observed morphology, architecture, cytocompatibility, and biomechanics of the scaffolds demonstrated their improved bio-physico-chemical properties. The formation of the transitional regions was augmented via enhanced delivery of two transcription factors, sex determining region Y-box 9 and runt-related transcription factor 2, which also triggered early up-regulated expression of cartilage- and bone-relevant markers, according to quantitative PCR and immunoblot analyses. Gradient tissue-specific matrix formation was also confirmed within the predesignated regions via histological staining and immunofluorescence assays. These results suggest that a transitional interface could be replicated on an engineered tendon through stratified tissue integration. The scaffold offers the advantages of a multitissue transition involving controlled cellular interactions and matrix heterogeneity, which can be applied for the regeneration of the ligament-bone interface. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  14. Five-Strand versus Four-Strand Hamstring Tendon Graft Technique for Anterior Cruciate Ligament Reconstruction: A Biomechanical Comparison.

    Science.gov (United States)

    Vaillant, Eric R; Parks, Brent G; Camire, Lyn M; Hinton, Richard Y

    2017-11-01

    The aim of this article is to compare diameter and stiffness, displacement, and strain in a five-strand versus four-strand hamstring graft for anterior cruciate ligament reconstruction. Eight matched pairs of lower extremities underwent four-strand or five-strand hamstring graft reconstruction. Diameter was significantly higher in the five-strand versus the four-strand construct ( p  = 0.002). No significant difference was found between the groups in construct displacement or stiffness. Significantly higher strain was observed in the inner limb versus the outer limb in the four-strand construct ( p  = 0.001) and in the inner limb versus the fifth limb in the 5-strand construct ( p  = 0.004). A fifth limb added to a four-strand hamstring graft significantly increased graft diameter but did not significantly change stiffness or displacement, suggesting that attachment of additional graft material via suture did not provide for full incorporation of the added limb into the graft at time zero. The inner limb in both constructs absorbed significantly greater load than did other limbs. The use of suture to attach additional material to a four-strand hamstring graft may not contribute to improved biomechanical qualities of the graft at time zero. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. Clinical evaluation of bone- patellar tendon- bone grafts for anterior cruciate ligament injury

    International Nuclear Information System (INIS)

    Nakamura, Yasuhiro

    2011-01-01

    One thousand and thirty-eight cases of Anterior Cruciate Ligament (ACL) rupture were treated between January 2002 and November 2010. Eight hundred sixty-six cases (83.9%) were observed for at least six months. All cases were reconstructed with a bone to tendon to bone (BTB) graft from the patella. Much effort was made to return the patient to a competitive sports activity level within one year. The age at suffering from the initial injury ranged from 9 to 74 years old with a mean of 24.7 years old. There were 493 female (50.7%) and 427 male (49.3%) cases. The injured side was right in 408 cases and left in 458 cases. The mean postoperative observation period was 449.2 days. The number of patients who felt 80% or more certain that they could return to competitive sports activities was 538 (61.9%). From the MRI findings, continuity of the reconstructed graft was observed in 793 cases (98.5%). Arthroscopy after reconstruction was performed in 775 cases (89.5%). The reconstructed ACL was observed to be covered with an adequate synovium in 629 cases (81.2%). The medial meniscus and lateral meniscus showed no changes in 657 cases (84.8%) and 666 cases (85.9%) respectively. Reconstructions performed less than two weeks after injury showed no significant differences in terms of Range Of Motion (ROM), arthroscopic findings, or the number of patients who could return to competitive sports activities. Statistically significantly more patients who underwent their reconstruction at an age over forty experienced a loss motion of five degree in extension or ten degree in flexion and resumed a lower level of sports activities. Patients who underwent the reconstruction could return to exercises for muscle strengthening and ROMs within 2 weeks. Patients over forty years old who underwent their reconstruction could prevent their menisci from fraying, tearing, or undergoing osteoarthritic changes. (author)

  16. Full-Thickness Skin Grafting with De-Epithelization of the Wound Margin for Finger Defects with Bone or Tendon Exposure

    Directory of Open Access Journals (Sweden)

    Jun Hee Lee

    2015-05-01

    Full Text Available BackgroundFull-thickness skin grafts (FTSGs are generally considered unreliable for coverage of full-thickness finger defects with bone or tendon exposure, and there are few clinical reports of its use in this context. However, animal studies have shown that an FTSG can survive over an avascular area ranging up to 12 mm in diameter. In our experience, the width of the exposed bones or tendons in full-thickness finger defects is <7 mm. Therefore, we covered the bone- or tendon-exposed defects of 16 fingers of 10 patients with FTSGs.MethodsThe surgical objectives were healthy granulation tissue formation in the wound bed, marginal de-epithelization of the normal skin surrounding the defect, preservation of the subdermal plexus of the central graft, and partial excision of the dermis along the graft margin. The donor site was the mastoid for small defects and the groin for large defects.ResultsMost of the grafts (15 of 16 fingers survived without significant surgical complications and achieved satisfactory functional and aesthetic results. Minor complications included partial graft loss in one patient, a minimal extension deformity in two patients, a depression deformity in one patient, and mild hyperpigmentation in four patients.ConclusionsWe observed excellent graft survival with this method with no additional surgical injury of the normal finger, satisfactory functional and aesthetic outcomes, and no need for secondary debulking procedures. Potential disadvantages include an insufficient volume of soft tissue and graft hyperpigmentation. Therefore, FTSGs may be an option for treatment of full-thickness finger defects with bone or tendon exposure.

  17. Sensitivity of subject-specific models to Hill muscle-tendon model parameters in simulations of gait

    NARCIS (Netherlands)

    Carbone, V.; Krogt, M.M. van der; Koopman, H.F.J.M.; Verdonschot, N.J.

    2016-01-01

    Subject-specific musculoskeletal (MS) models of the lower extremity are essential for applications such as predicting the effects of orthopedic surgery. We performed an extensive sensitivity analysis to assess the effects of potential errors in Hill muscle-tendon (MT) model parameters for each of

  18. Pentadecapeptide BPC 157 Enhances the Growth Hormone Receptor Expression in Tendon Fibroblasts

    Directory of Open Access Journals (Sweden)

    Chung-Hsun Chang

    2014-11-01

    Full Text Available BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

  19. Dorsiflexion capacity affects achilles tendon loading during drop landings.

    Science.gov (United States)

    Whitting, John W; Steele, Julie R; McGhee, Deirdre E; Munro, Bridget J

    2011-04-01

    Evidence suggests a link between decreased dorsiflexion range of motion (DROM) and injury risk during landings. The purpose of this study was to determine the effect of weight-bearing DROM on ankle mechanics during drop landings. Forty-eight men (mean ± SD = 22.5 ± 4.7 yr) were measured for DROM. Participants performed drop landings onto a force platform at two vertical descent velocities (2.25 ± 0.15 and 3.21 ± 0.17 m·s(-1)), while EMG activity of four shank muscles and three-dimensional ankle joint kinematics were recorded. Participants were classified into low (37.7° ± 2.5°) and high (48.4° ± 2.5°) DROM groups. Ground reaction force, EMG, dorsiflexion angle, plantarflexion moment, and Achilles tendon force outcome variables were all equivalent for the two DROM groups during each landing condition. However, the low DROM group performed each landing condition at a significantly greater percentage of their DROM and displayed significantly more ankle eversion throughout most of the movement. The low and high DROM groups displayed DROM percentages of 27 ± 11 and 10 ± 11 (P = 0.013), 32 ± 9 and 23 ± 9 (P = 0.056), 60 ± 13 and 46 ± 13 (P = 0.004), and 66 ± 16 and 54 ± 9 (P = 0.003) when they encountered the peak plantarflexion moments, Achilles tendon force, eversion angles, and dorsiflexion angles, respectively. Participants with a low DROM absorbed the landing impact forces with their plantarflexor muscle-tendon units in a more lengthened and everted position. Athletes with a low DROM may be more likely to regularly overload their plantarflexor muscle-tendon units, thereby potentially exposing themselves to a higher likelihood of incurring injuries such as Achilles tendinopathy.

  20. Comparison of the Hamstring Muscle Activity and Flexion-Relaxation Ratio between Asymptomatic Persons and Computer Work-related Low Back Pain Sufferers.

    Science.gov (United States)

    Kim, Min-Hee; Yoo, Won-Gyu

    2013-05-01

    [Purpose] The purpose of this study was to compare the hamstring muscle (HAM) activities and flexion-relaxation ratios of an asymptomatic group and a computer work-related low back pain (LBP) group. [Subjects] For this study, we recruited 10 asymptomatic computer workers and 10 computer workers with work-related LBP. [Methods] We measured the RMS activity of each phase (flexion, full-flexion, and re-extension phase) of trunk flexion and calculated the flexion-relaxation (FR) ratio of the muscle activities of the flexion and full-flexion phases. [Results] In the computer work-related LBP group, the HAM muscle activity increased during the full-flexion phase compared to the asymptomatic group, and the FR ration was also significantly higher. [Conclusion] We thought that prolonged sitting of computer workers might cause the change in their HAM muscle activity pattern.

  1. The theory and technique of yamuna body rolling.

    Science.gov (United States)

    Suzuki, Satoshi

    2013-09-01

    [Purpose] This paper provides information about the theory and technique of Yamuna Body Rolling. In order to treat physical problems, using the specialized Yamuna Body Rolling balls, people can target superficial skin, fasciae, muscle fibers, tendons, ligaments, bones, internal organs, and the nervous system by themselves. The extraordinary effect of Yamuna Body Rolling is its multidimensional elongation of muscle fibers. In addition to the regular longitudinal elongation by the conventional stretch method, Yamuna Body Rolling enables the transversal and diagonal expansion of muscle fibers in order to move the body more dynamically. Hamstring, abdominal, and sideline routines are presented as examples for techniques of Yamuna Body Rolling. Yamuna Body Rolling can be applied to functional evaluation and therapeutic uses; therefore, it could provide many benefits in the treatment of different conditions in the medical field.

  2. Self-Myofascial Release: No Improvement of Functional Outcomes in 'Tight' Hamstrings.

    Science.gov (United States)

    Morton, Robert W; Oikawa, Sara Y; Phillips, Stuart M; Devries, Michaela C; Mitchell, Cameron J

    2016-07-01

    Self-myofascial release (SMR) is a common exercise and therapeutic modality shown to induce acute improvements in joint range of motion (ROM) and recovery; however, no long-term studies have been conducted. Static stretching (SS) is the most common method used to increase joint ROM and decrease muscle stiffness. It was hypothesized that SMR paired with SS (SMR+SS) compared with SS alone over a 4-wk intervention would yield greater improvement in knee-extension ROM and hamstring stiffness. 19 men (22 ± 3 y) with bilateral reduced hamstring ROM had each of their legs randomly assigned to either an SMR+SS or an SS-only group. The intervention consisted of 4 repetitions of SS each for 45 s or the identical amount of SS preceded by 4 repetitions of SMR each for 60 s and was performed on the respective leg twice daily for 4 wk. Passive ROM, hamstring stiffness, rate of torque development (RTD), and maximum voluntary contraction (MVC) were assessed pre- and postintervention. Passive ROM (P Hamstring stiffness toward end-ROM was reduced postintervention (P = .02). There were no differences between the intervention groups for any variable. The addition of SMR to SS did not enhance the efficacy of SS alone. SS increases joint ROM through a combination of decreased muscle stiffness and increased stretch tolerance.

  3. Mechanical and morphological properties of different muscle-tendon units in the lower extremity and running mechanics: effect of aging and physical activity.

    Science.gov (United States)

    Karamanidis, Kiros; Arampatzis, Adamantios

    2005-10-01

    The objectives of this work were (i) to investigate whether chronic endurance running is a sufficient stimulus to counteract the age-related changes in the mechanical and morphological properties of human triceps surae (TS) and quadriceps femoris (QF) muscle-tendon units (MTUs) by comparing runners and non-active subjects at different ages (young and old), (ii) to identify adaptational phenomena in running mechanics due to age-related changes in the mechanical and morphological properties of the TS and QF MTUs, and finally (iii) to examine whether chronic endurance-running exercise is associated with adaptational effects on running characteristics in old and young adults. The investigation was conducted on 30 old and 19 young adult males divided into two subgroups according to their running activity: endurance-runners vs non-active. To analyse the properties of the MTUs, all subjects performed isometric maximal voluntary (MVC) ankle plantarflexion and knee extension contractions at 11 different MTU lengths on a dynamometer. The activation of the TS and QF during MVC was estimated by surface electromyography. The gastrocnemius medialis and the vastus lateralis and their distal aponeuroses were visualized by ultrasonography at rest and during MVC, respectively. Ground reaction forces and kinematic data were recorded during running trials at 2.7 m s(-1). The TS and QF MTU capacities were reduced with aging (lower muscle strength and lower tendon stiffness). Runners and non-active subjects had similar MTU properties, suggesting that chronic endurance-running exercise does not counteract the age-related degeneration of the MTUs. Runners showed a higher mechanical advantage for the QF MTU while running (lower gear ratio) compared to non-active subjects, indicating a task-specific adaptation even at old age. Older adults reacted to the reduced capacities of their MTUs by increasing running safety (higher duty factor, lower flight time) and benefitting from a mechanical

  4. Prolonged electrical stimulation-induced gluteal and hamstring muscle activation and sitting pressure in spinal cord injury: Effect of duty cycle

    OpenAIRE

    Christof A. J. Smit, MD; Karin J. A. Legemate, MSc; Anja de Koning, MSc; Sonja de Groot, PhD; Janneke M. Stolwijk-Swuste, MD, PhD; Thomas W. J. Janssen, PhD

    2013-01-01

    Pressure ulcers (PUs) are highly prevalent in people with spinal cord injury (SCI). Electrical stimulation (ES) activates muscles and might reduce risk factors. Our objectives were to study and compare the effects of two duty cycles during 3 h of ES-induced gluteal and hamstring activation on interface pressure distribution in sitting individuals with SCI and study the usability of a newly developed electrode garment (ES shorts). Ten individuals with SCI participated in this study, in which t...

  5. Transportal anterior cruciate ligament reconstruction with quadrupled hamstring tendon graft: A prospective outcome study

    Directory of Open Access Journals (Sweden)

    Chandan Kumar

    2017-01-01

    Full Text Available Background: Anterior cruciate ligament (ACL reconstruction has been one of the most commonly performed procedures throughout the world. Unsatisfactory outcome with conventional ACL reconstruction has been attributed to nonanatomic graft placement. Researchers have advised placing the graft in the native footprint of ACL to avoid nonanatomic graft placement. The goal of this study was to analyze the outcome of anatomic single bundle ACL reconstruction using transportal technique. Materials and Methods: This was a prospective outcome study conducted on 85 consecutive patients of ACL reconstruction of which 62 patients met inclusion and exclusion criteria and were analyzed for final results. All the patients underwent ACL reconstruction by quadrupled hamstring tendon graft using transportal technique and the accessory anteromedial (AAM portal for femoral tunnel creation. The graft was fixed with endobutton on femoral side and bioabsorbable screw on the tibial side. Patients were evaluated for range of motion, International Knee Documentation Committee (IKDC score, and Lysholm scores at a minimum followup period of 2 years. The mean pre- and postoperative scores were compared using Wilcoxon signed-rank test. Results: The mean Lysholm and IKDC scores improved significantly (P < 0.0001 from preoperative value. According to IKDC score, 90.3% (n = 56 were either normal or near normal at final followup. According to Lysholm score, 75.8% of patients had excellent and 13.3% had good results. Preoperatively, pivot shift was present in 85.5% (n = 53 of patients which reduced to 4.8% (n = 3 postoperatively. Infection and knee stiffness occurred in two patients, and femoral tunnel blowout and graft re-rupture occurred in one patient each. Conclusion: Anatomic ACL reconstruction by AAM portal is a reproducible technique which gives good clinical outcome at short-term followup.

  6. Intraoperative muscle electrical stimulation for accurate positioning of the temporalis muscle tendon during dynamic, one-stage lengthening temporalis myoplasty for facial and lip reanimation.

    Science.gov (United States)

    Har-Shai, Yaron; Gil, Tamir; Metanes, Issa; Labbé, Daniel

    2010-07-01

    Facial paralysis is a significant functional and aesthetic handicap. Facial reanimation is performed either by two-stage microsurgical methods or by regional one-stage muscle pedicle flaps. Labbé has modified and improved the regional muscle pedicle transfer flaps for facial reanimation (i.e., the lengthening temporalis myoplasty procedure). This true myoplasty technique is capable of producing a coordinated, spontaneous, and symmetrical smile. An intraoperative electrical stimulation of the temporal muscle is proposed to simulate the smile of the paralyzed side on the surgical table. The intraoperative electrical stimulation of the temporalis muscle, employing direct percutaneous electrode needles or transcutaneous electrical stimulation electrodes, was utilized in 11 primary and four secondary cases with complete facial palsy. The duration of the facial paralysis was up to 12 years. Postoperative follow-up ranged from 3 to 12 months. The insertion points of the temporalis muscle tendon to the nasolabial fold, upper lip, and oral commissure had been changed according to the intraoperative muscle stimulation in six patients of the 11 primary cases (55 percent) and in all four secondary (revisional) cases. A coordinated, spontaneous, and symmetrical smile was achieved in all patients by 3 months after surgery by employing speech therapy and biofeedback. This adjunct intraoperative refinement provides crucial feedback for the surgeon in both primary and secondary facial palsy cases regarding the vector of action of the temporalis muscle and the accuracy of the anchoring points of its tendon, thus enhancing a more coordinated and symmetrical smile.

  7. Lean muscle volume of the thigh has a stronger relationship with muscle power than muscle strength in women with knee osteoarthritis.

    Science.gov (United States)

    Davison, Michael J; Maly, Monica R; Keir, Peter J; Hapuhennedige, Sandani M; Kron, Amie T; Adachi, Jonathan D; Beattie, Karen A

    2017-01-01

    Thigh lean muscle and intramuscular fat have been implicated in the impairment of physical function observed in people with knee osteoarthritis. We investigated the relationships of quadriceps and hamstrings intramuscular fat fraction and lean muscle volume with muscle power and strength, controlling for neuromuscular activation, and physical performance in women with knee OA. Women (n=20) 55years or older with symptomatic, radiographic knee osteoarthritis underwent a 3.0T magnetic resonance imaging scan of the thigh of their most symptomatic knee. Axial fat-separated images were analyzed using software to quantify intramuscular fat and lean muscle volumes of the quadriceps and hamstrings. To quantify strength and power of the knee extensors and flexors, participants performed maximum voluntary isometric contraction and isotonic knee extensions and flexions, respectively. Electromyography of the quadriceps and hamstrings was measured. Participants also completed five physical performance tests. Quadriceps and hamstrings lean muscle volumes were related to isotonic knee extensor (B=0.624; p=0.017) and flexor (B=1.518; p=0.032) power, but not knee extensor (B=0.001; p=0.615) or flexor (B=0.001; p=0.564) isometric strength. Intramuscular fat fractions were not related to isotonic knee extensor or flexor power, nor isometric strength. No relationships were found between intramuscular fat or lean muscle volume and physical performance. Muscle power may be more sensitive than strength to lean muscle mass in women with knee osteoarthritis. Thigh lean muscle mass, but neither intramuscular nor intermuscular fat, is related to knee extensor and flexor power in women with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Short-term strength training and the expression of myostatin and IGF-I isoforms in rat muscle and tendon

    DEFF Research Database (Denmark)

    Heinemeier, K M; Olesen, J L; Schjerling, P

    2007-01-01

    In skeletal muscle, an increased expression of insulin like growth factor-I isoforms IGF-IEa and mechano-growth factor (MGF) combined with downregulation of myostatin is thought to be essential for training-induced hypertrophy. However, the specific effects of different contraction types on regul......In skeletal muscle, an increased expression of insulin like growth factor-I isoforms IGF-IEa and mechano-growth factor (MGF) combined with downregulation of myostatin is thought to be essential for training-induced hypertrophy. However, the specific effects of different contraction types...... on regulation of these factors in muscle are still unclear, and in tendon the functions of myostatin, IGF-IEa, and MGF in relation to training are unknown. Female Sprague-Dawley rats were subjected to 4 days of concentric, eccentric, or isometric training (n = 7-9 per group) of the medial gastrocnemius......, by stimulation of the sciatic nerve during general anesthesia. mRNA levels for myostatin, IGF-IEa, and MGF in muscle and Achilles' tendon were measured by real-time RT-PCR. Muscle myostatin mRNA decreased in response to all types of training (2- to 8-fold) (P

  9. A previous hamstring injury affects kicking mechanics in soccer players.

    Science.gov (United States)

    Navandar, Archit; Veiga, Santiago; Torres, Gonzalo; Chorro, David; Navarro, Enrique

    2018-01-10

    Although the kicking skill is influenced by limb dominance and sex, how a previous hamstring injury affects kicking has not been studied in detail. Thus, the objective of this study was to evaluate the effect of sex and limb dominance on kicking in limbs with and without a previous hamstring injury. 45 professional players (males: n=19, previously injured players=4, age=21.16 ± 2.00 years; females: n=19, previously injured players=10, age=22.15 ± 4.50 years) performed 5 kicks each with their preferred and non-preferred limb at a target 7m away, which were recorded with a three-dimensional motion capture system. Kinematic and kinetic variables were extracted for the backswing, leg cocking, leg acceleration and follow through phases. A shorter backswing (20.20 ± 3.49% vs 25.64 ± 4.57%), and differences in knee flexion angle (58 ± 10o vs 72 ± 14o) and hip flexion velocity (8 ± 0rad/s vs 10 ± 2rad/s) were observed in previously injured, non-preferred limb kicks for females. A lower peak hip linear velocity (3.50 ± 0.84m/s vs 4.10 ± 0.45m/s) was observed in previously injured, preferred limb kicks of females. These differences occurred in the backswing and leg-cocking phases where the hamstring muscles were the most active. A variation in the functioning of the hamstring muscles and that of the gluteus maximus and iliopsoas in the case of a previous injury could account for the differences observed in the kicking pattern. Therefore, the effects of a previous hamstring injury must be considered while designing rehabilitation programs to re-educate kicking movement.

  10. The effect of eccentric and concentric calf muscle training on Achilles tendon stiffness.

    Science.gov (United States)

    Morrissey, Dylan; Roskilly, Anna; Twycross-Lewis, Richard; Isinkaye, Tomide; Screen, Hazel; Woledge, Roger; Bader, Dan

    2011-03-01

    To compare in vivo effects of eccentric and concentric calf muscle training on Achilles tendon stiffness, in subjects without tendinopathy. Thirty-eight recreational athletes completed 6 weeks eccentric (6 males, 13 females, 21.6  ±  2.2 years) or concentric training (8 males, 11 females, 21.1  ±  2.0 years). Achilles tendon stiffness, tendon modulus and single-leg jump height were measured before and after intervention. Exercise adherence was recorded using a diary. All data are reported as mean  ±  SD. Groups were matched for height and weight but the eccentric training group were more active at baseline (P Tendon stiffness was higher in the eccentrically trained group at baseline compared to the concentrically trained group (20.9  ±  7.3 N/mm v 13.38  ±  4.66 N/mm; P = 0.001) and decreased significantly after eccentric training (to 17.2 ( ±  5.9) N/mm (P = 0.035)). There was no stiffness change in the concentric group (P = 0.405). Stiffness modulus showed similar changes to stiffness. An inverse correlation was found between initial, and subsequent, reduction in stiffness (r = -0.66). Jump height did not change and no correlation between stiffness change and adherence was observed in either group (r = 0.01). Six weeks of eccentric training can alter Achilles tendon stiffness while a matched concentric programme shows no similar effects. Studies in patients with Achilles tendinopathy are warranted.

  11. Exercise and Regulation of Bone and Collagen Tissue Biology

    DEFF Research Database (Denmark)

    Kjaer, Michael; Jørgensen, Niklas Rye; Heinemeier, Katja

    2015-01-01

    The musculoskeletal system and its connective tissue include the intramuscular connective tissue, the myotendinous junction, the tendon, the joints with their cartilage and ligaments, and the bone; they all together play a crucial role in maintaining the architecture of the skeletal muscle, ensur...

  12. Knitted poly-lactide-co-glycolide scaffold loaded with bone marrow stromal cells in repair and regeneration of rabbit Achilles tendon.

    Science.gov (United States)

    Ouyang, Hong Wei; Goh, James C H; Thambyah, Ashvin; Teoh, Swee Hin; Lee, Eng Hin

    2003-06-01

    The objectives of this study were to evaluate the morphology and biomechanical function of Achilles tendons regenerated using knitted poly-lactide-co-glycolide (PLGA) loaded with bone marrow stromal cells (bMSCs). The animal model used was that of an adult female New Zealand White rabbit with a 10-mm gap defect of the Achilles tendon. In group I, 19 hind legs with the created defects were treated with allogeneic bMSCs seeded on knitted PLGA scaffold. In group II, the Achilles tendon defects in 19 hind legs were repaired using the knitted PLGA scaffold alone, and in group III, 6 hind legs were used as normal control. The tendon-implant constructs of groups I and II were evaluated postoperatively at 2, 4, 8, and 12 weeks using macroscopic, histological, and immunohistochemical techniques. In addition, specimens from group I (n = 7), group II (n = 7), and group III (n = 6) were harvested for biomechanical test 12 weeks after surgery. Postoperatively, at 2 and 4 weeks, the histology of group I specimens exhibited a higher rate of tissue formation and remodeling as compared with group II, whereas at 8 and 12 weeks postoperation, the histology of both group I and group II was similar to that of native tendon tissue. The wound sites of group I healed well and there was no apparent lymphocyte infiltration. Immunohistochemical analysis showed that the regenerated tendons were composed of collagen types I and type III fibers. The tensile stiffness and modulus of group I were 87 and 62.6% of normal tendon, respectively, whereas those of group II were about 56.4 and 52.9% of normal tendon, respectively. These results suggest that the knitted PLGA biodegradable scaffold loaded with allogeneic bone marrow stromal cells has the potential to regenerate and repair gap defect of Achilles tendon and to effectively restore structure and function.

  13. Functional Outcomes and Return to Sports After Acute Repair, Chronic Repair, and Allograft Reconstruction for Proximal Hamstring Ruptures.

    Science.gov (United States)

    Rust, David A; Giveans, M Russell; Stone, Rebecca M; Samuelson, Kathryn M; Larson, Christopher M

    2014-06-01

    There are limited data regarding outcomes and return to sports after surgery for acute versus chronic proximal hamstring ruptures. Surgery for chronic proximal hamstring ruptures leads to improved outcomes and return to sports but at a lower level than with acute repair. Proximal hamstring reconstruction with an Achilles allograft for chronic ruptures is successful when direct repair is not possible. Cohort study; Level of evidence, 3. Between 2002 and 2012, a total of 72 patients with a traumatic proximal hamstring rupture (51 acute, 21 chronic) underwent either direct tendon repair with suture anchors (n = 58) or Achilles allograft tendon reconstruction (n = 14). Results from the Single Assessment Numeric Evaluation (SANE) for activities of daily living (ADL) and sports-related activities, Short Form-12 (SF-12), visual analog scale (VAS), and a patient satisfaction questionnaire were obtained. The mean time to surgery in the chronic group was 441.4 days versus 17.8 days in the acute group. At a mean follow-up of 45 months, patients with chronic tears had inferior sports activity scores (70.2% vs 80.3%, respectively; P = .026) and a trend for decreased ADL scores (86.5% vs 93.3%, respectively; P = .085) compared with those with acute tears. Patients with chronic tears, however, reported significant improvements postoperatively for both sports activity scores (30.3% to 70.2%; P sports activity scores equal to those of chronic repair (P = .507 and P = .904, respectively). There were no significant differences between groups in SF-12, VAS, or patient satisfaction outcomes (mean, 85.2% satisfaction overall). Acute repair was superior to chronic surgery with regard to return to sports. Acute and chronic proximal hamstring repair and allograft reconstruction had favorable results for ADL. For low-demand patients or those with medical comorbidities, delayed repair or reconstruction might be considered with an expected 87% return to normal ADL. For patients who desire to

  14. MRI and gross anatomy of the iliopsoas tendon complex

    International Nuclear Information System (INIS)

    Polster, Joshua M.; Lee, Ho; Klika, Alison; Barsoum, Wael; Drake, Richard; Elgabaly, Mohamed

    2008-01-01

    The objective was to explain the anatomic basis of a longitudinal cleft of increased signal in the iliopsoas tendon seen on hip MR arthrograms. A prospective review of 20 MR hip arthrograms was performed using standard and fat-suppressed T1-weighted images to establish whether or not the cleft was composed of fatty tissue and to define the anatomy of the iliopsoas tendon complex. Three cadaver dissections of the hip region were then performed for anatomic correlation. Fourteen out of 20 MR hip arthrograms demonstrated a longitudinal cleft of increased T1 signal adjacent to the iliopsoas tendon, which suppressed on frequency selective fat-suppressed images, indicating fatty composition. Gross anatomic correlation demonstrated this fatty cleft to represent a fascial plane adjacent to the iliopsoas tendon, in one case separating the iliopsoas tendon medially from a thin intramuscular tendon within the lateral portion of the iliacus muscle. Also noted was a direct muscular insertion of the lateral portion of the iliacus muscle onto the anterior portion of the proximal femoral diaphysis in all 3 cadavers. The anatomy of the iliopsoas tendon complex is more complicated than typically illustrated and includes the iliopsoas tendon itself attaching to the lesser trochanter, the lateral portion of the iliacus muscle attaching directly upon the anterior portion of the proximal femoral diaphysis, and a thin intramuscular tendon within this lateral iliacus muscle that is separated from the iliopsoas tendon by a cleft of fatty fascia that accounts for the MRI findings of a cleft of increased T1 signal. (orig.)

  15. STRETCHING EXERCISES - EFFECT ON PASSIVE EXTENSIBILITY AND STIFFNESS IN SHORT HAMSTRINGS OF HEALTHY-SUBJECTS

    NARCIS (Netherlands)

    HALBERTSMA, JPK; GOEKEN, LNH

    Passive muscle stretch tests are common practice in physical therapy and rehabilitation medicine. However, the effects of stretching exercises are not well known. With an instrumental straight-leg-raising set-up the extensibility, stiffness, and electromyographic activity of the hamstring muscles

  16. An Accurate and Dynamic Computer Graphics Muscle Model

    Science.gov (United States)

    Levine, David Asher

    1997-01-01

    A computer based musculo-skeletal model was developed at the University in the departments of Mechanical and Biomedical Engineering. This model accurately represents human shoulder kinematics. The result of this model is the graphical display of bones moving through an appropriate range of motion based on inputs of EMGs and external forces. The need existed to incorporate a geometric muscle model in the larger musculo-skeletal model. Previous muscle models did not accurately represent muscle geometries, nor did they account for the kinematics of tendons. This thesis covers the creation of a new muscle model for use in the above musculo-skeletal model. This muscle model was based on anatomical data from the Visible Human Project (VHP) cadaver study. Two-dimensional digital images from the VHP were analyzed and reconstructed to recreate the three-dimensional muscle geometries. The recreated geometries were smoothed, reduced, and sliced to form data files defining the surfaces of each muscle. The muscle modeling function opened these files during run-time and recreated the muscle surface. The modeling function applied constant volume limitations to the muscle and constant geometry limitations to the tendons.

  17. The Diagnostic and Prognostic Value of Ultrasonography in Soccer Players With Acute Hamstring Injuries

    DEFF Research Database (Denmark)

    Petersen, Jesper; Thorborg, Kristian; Nielsen, Michael Bachmann

    2014-01-01

    BACKGROUND: An injury to the hamstring muscle complex is the most common injury in soccer. Ultrasound of acute hamstring injuries is often used as a clinical tool for diagnosing hamstring injuries and guiding players in when they can return to play. PURPOSE: To (1) investigate the characteristic......) to investigate if ultrasonography can be used as a prognostic indicator of time to return to play. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Players from 50 teams participating in 1 of the top 5 Danish soccer divisions were followed in the period from January to December 2008. Of 67 players...

  18. Rupture of the long tendon of the biceps brachi muscle. An unusual case related to use of the pneumatic tourniquet.

    Science.gov (United States)

    Logel, R J

    1976-01-01

    Tourniquet paralysis, arterial spasm, aneurysm formation, and the post-ischemic hand syndrome are all complications of penumatic tourniquet use in surgery of the extremities. This is a case report of another complication of tourniquet use, rupture of the long tendon of the biceps brachii muscle. Some underlying pathologic or degenerative condition usually exists before rupture can occur. Both rheumatoid arthritis and local corticosteroid injections into the long tendon of the biceps probably accounted for weakening the tensile strength of the tendon and subsequent rupture in the case described.

  19. Evaluation of 99mTc-MDP bone imaging in monitoring the muscle-pedicle bone graft osteogenic activation

    International Nuclear Information System (INIS)

    Sang Shibiao; Wu Yiwei; Zhang Wei; Jiang Yimin; Chen Guangxiang; Dong Tianhua

    2002-01-01

    Nine mature and healthy dogs were divided into 4 groups randomly. The first group consists of 3 dogs, and the rest groups, 2 dogs. Self-control way was used. The left ilium was the experimental site, where the bone piece with sartorial muscle attached was cut from ilium. The right side served as control, where the graft bone from ilium was wrapped up with silica gel, then fixed subcutaneously. The pedicled bone pieces were retrieved in 2, 4, 6, 8 weeks after surgery, the size of graft bones from two sides were the same. Survival range, osteogenic formation of muscle-pedicle bone were examined by 99m Tc-MDP bone imaging and histological method to evaluate the clinical value of treatment of ischemic osteonecrosis of the femoral head with muscle-pedicle bone grafting. The results were as follows: 1. The part of bone attached by the sartorial survived, but osteonecrosis was observed at the location of 1.2-1.7 cm from attached point of muscle. 2. There were two forms observed in the course of osteogenic activation of muscle-pedicle bone. Under the reduction of mechanical stimulation and blood supply, bone marrow tissue was replaced by fibro-granulation tissue and new capillary in the survival part, while the survival bone of proximal part grew distally and gradually replace the dead bone of distal part. 3. Histological examination revealed that small amounts of fibro-granulation tissue and new capillary appeared in 2nd week, primary trabeculae appeared in 6th week, and in 8th week, some trabeculae recovered their normal appearance and osteogenic cell reduced remarkably. 4. Survival range of muscle-pedicle graft bone was directly proportional to the width of muscle pedicle. Therefore, radionuclide bone imaging and histological examination demonstrated that muscle-pedicle graft bone was a piece of bone with relatively poor blood supply, its effect is repairing necrosis and collapse of the femoral head is limited. 99m Tc-MDP bone imaging may be an effective and first

  20. Complex Anatomic Abnormalities of the Lower Leg Muscles and Tendons Associated With Phocomelia: A Case Report.

    Science.gov (United States)

    Hodo, Thomas; Hamrick, Mark; Melenevsky, Yulia

    Musculoskeletal anatomy is widely known to have components that stray from the norm in the form of variant muscle and tendon presence, absence, origin, insertion, and bifurcation. Although these variant muscles and tendons might be deemed incidental and insignificant findings by most, they can be important contributors to pathologic physiology or, more importantly, an option for effective treatment. In the present case report, we describe a patient with phocomelia and Müllerian abnormalities secondary to in utero thalidomide exposure. The patient had experienced recurrent bilateral foot pain accompanied by numbness, stiffness, swelling, and longstanding pes planus. These symptoms persisted despite conservative treatment with orthotics, steroids, and nonsteroidal anti-inflammatory drugs. Radiographic imaging showed dysmorphic and degenerative changes of the ankle and foot joints. Further investigation with magnetic resonance imaging revealed complex anatomic abnormalities, including the absence of the posterior tibialis and peroneus brevis, lateralization of the peroneus longus, and the presence of a variant anterior compartment muscle. The variant structure was likely a previously described anterior compartment variant, anterior fibulocalcaneus, and might have been a source of the recurrent pain. Also, the absence of the posterior tibialis might have caused the pes planus in the present patient, considering that posterior tibialis tendon dysfunction is the most common cause of acquired pes planus. Although thalidomide infrequently affects the lower extremities, its effects on growth and development were likely the cause of this rare array of anatomic abnormalities and resulting ankle and foot pathologic features. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  1. No Relationship Between Hamstring Flexibility and Hamstring Injuries in Male Amateur Soccer Players: A Prospective Study.

    Science.gov (United States)

    van Doormaal, Mitchell C M; van der Horst, Nick; Backx, Frank J G; Smits, Dirk-Wouter; Huisstede, Bionka M A

    2017-01-01

    In soccer, although hamstring flexibility is thought to play a major role in preventing hamstring injuries, the relationship between hamstring flexibility and hamstring injuries remains unclear. To investigate the relationship between hamstring flexibility and hamstring injuries in male amateur soccer players. Case-control study; Level of evidence, 3. This study included 450 male first-class amateur soccer players (mean age, 24.5 years). Hamstring flexibility was measured by performing the sit-and-reach test (SRT). The relationship between hamstring flexibility and the occurrence of hamstring injuries in the following year, while adjusting for the possible confounding effects of age and previous hamstring injuries, was determined with a multivariate logistic regression analysis. Of the 450 soccer players, 21.8% reported a hamstring injury in the previous year. The mean (±SD) baseline score for the SRT was 21.2 ± 9.2 cm. During the 1-year follow-up period, 23 participants (5.1%) suffered a hamstring injury. In the multivariate analysis, while adjusting for age and previous injuries, no significant relationship was found between hamstring flexibility and hamstring injuries ( P = .493). In this group of soccer players, hamstring flexibility (measured with the SRT) was not related to hamstring injuries. Age and previous hamstring injuries as possible confounders did not appear to influence this relationship. Other etiological factors need to be examined to further elucidate the mechanism of hamstring injuries.

  2. Biomechanical comparison of expanded polytetrafluoroethylene (ePTFE) and PTFE interpositional patches and direct tendon-to-bone repair for massive rotator cuff tears in an ovine model.

    Science.gov (United States)

    McKeown, Andrew Dj; Beattie, Rebekah F; Murrell, George Ac; Lam, Patrick H

    2016-01-01

    Massive irreparable rotator cuff tears are a difficult problem. Modalities such as irrigation and debridement, partial repair, tendon transfer and grafts have been utilized with high failure rates and mixed results. Synthetic interpositional patch repairs are a novel and increasingly used approach. The present study aimed to examine the biomechanical properties of common synthetic materials for interpositional repairs in contrast to native tendon. Six ovine tendons, six polytetrafluoroethylene (PTFE) felt sections and six expanded PTFE (ePTFE) patch sections were pulled-to-failure to analyze their biomechanical and material properties. Six direct tendon-to-bone surgical method repairs, six interpositional PTFE felt patch repairs and six interpositional ePTFE patch repairs were also constructed in ovine shoulders and pulled-to-failure to examine the biomechanical properties of each repair construct. Ovine tendon had higher load-to-failure (591 N) and had greater stiffness (108 N/mm) than either PTFE felt (296 N, 28 N/mm) or ePTFE patch sections (323 N, 34 N/mm). Both PTFE felt and ePTFE repair techniques required greater load-to-failure (225 N and 177 N, respectively) than direct tendon-to-bone surgical repairs (147 N) in ovine models. Synthetic materials lacked several biomechanical properties, including strength and stiffness, compared to ovine tendon. Interpositional surgical repair models with these materials were significantly stronger than direct tendon-to-bone model repairs.

  3. Sciatic Nerve Injury After Proximal Hamstring Avulsion and Repair.

    Science.gov (United States)

    Wilson, Thomas J; Spinner, Robert J; Mohan, Rohith; Gibbs, Christopher M; Krych, Aaron J

    2017-07-01

    Muscle bellies of the hamstring muscles are intimately associated with the sciatic nerve, putting the sciatic nerve at risk of injury associated with proximal hamstring avulsion. There are few data informing the magnitude of this risk, identifying risk factors for neurologic injury, or determining neurologic outcomes in patients with distal sciatic symptoms after surgery. To characterize the frequency and nature of sciatic nerve injury and distal sciatic nerve-related symptoms after proximal hamstring avulsion and to characterize the influence of surgery on these symptoms. Cohort study; Level of evidence, 3. This was a retrospective review of patients with proximal partial or complete hamstring avulsion. The outcome of interest was neurologic symptoms referable to the sciatic nerve distribution below the knee. Neurologic symptoms in operative patients were compared pre- and postoperatively. The cohort consisted of 162 patients: 67 (41.4%) operative and 95 (58.6%) nonoperative. Sciatic nerve-related symptoms were present in 22 operative and 23 nonoperative patients, for a total of 45 (27.8%) patients (8 [4.9%] motor deficits, 11 [6.8%] sensory deficits, and 36 [22.2%] with neuropathic pain). Among the operative cohort, 3 of 3 (100.0%) patients showed improvement in their motor deficit postoperatively, 3 of 4 (75.0%) patients' sensory symptoms improved, and 17 of 19 (89.5%) patients had improvement in pain. A new or worsening deficit occurred in 5 (7.5%) patients postoperatively (2 [3.1%] motor deficits, 1 [1.5%] sensory deficit, and 3 [4.5%] with new pain). Predictors of operative intervention included lower age (odds ratio [OR], 0.952; 95% CI, 0.921-0.982; P = .001) and complete avulsion (OR, 10.292; 95% CI, 2.526-72.232; P hamstring avulsion are underrecognized. Currently, neurologic symptoms are not considered when determining whether to pursue operative intervention. Given the high likelihood of improvement with surgical treatment, neurologic symptoms should be

  4. Muscle and bone follow similar temporal patterns of recovery from muscle-induced disuse due to botulinum toxin injection.

    Science.gov (United States)

    Manske, Sarah L; Boyd, Steven K; Zernicke, Ronald F

    2010-01-01

    If muscle force is a primary source for triggering bone adaptation, with disuse and reloading, bone changes should follow muscle changes. We examined the timing and magnitude of changes in muscle cross-sectional area (MCSA) and bone architecture in response to muscle inactivity following botulinum toxin (BTX) injection. We hypothesized that MCSA would return to baseline levels sooner than bone properties following BTX injection. Female BALB mice (15 weeks old) were injected with 20 muL of BTX (1 U/100 g body mass, n=18) or saline (SAL, n=18) into the posterior calf musculature of one limb. The contralateral limb (CON) served as an internal control. MCSA and bone properties were assessed at baseline, 2, 4, 8, 12, and 16 weeks post-injection using in vivo micro-CT at the tibia proximal metaphysis (bone only) and diaphysis. Muscles were dissected and weighed after sacrifice. Significant GroupxLegxTime interactions indicated that the maximal decrease in MCSA (56%), proximal metaphyseal BV/TV (38%) and proximal diaphyseal Ct.Ar (7%) occurred 4 weeks after injection. There was no delay prior to bone recovery as both muscle and bone properties began to recover after this time, but MCSA and BV/TV remained 15% and 20% lower, respectively, in the BTX-injected leg than the BTX-CON leg 16 weeks post-injection. Gastrocnemius mass (primarily fast-twitch) was 14% lower in the BTX-injected leg than the SAL-injected leg, while soleus mass (primarily slow-twitch) was 15% greater in the BTX group than the SAL group. Our finding that muscle size and bone began to recover at similar times after BTX injection was unexpected. This suggested that partial weight-bearing and/or return of slow-twitch muscle activity in the BTX leg may have been sufficient to stimulate bone recovery. Alternatively, muscle function may have recovered sooner than MCSA. Our results indicated that muscle cross-sectional area, while important, may not be the primary factor associated with bone loss and recovery

  5. A systematic review of the concept and clinical applications of bone marrow aspirate concentrate in tendon pathology

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    Imam Mohamed A.

    2017-01-01

    Full Text Available Tendon pathologies are a group of musculoskeletal conditions frequently seen in clinical practice. They can be broadly classified into traumatic, degenerative and overuse-related tendinopathies. Rotator cuff tears, Achilles tendinopathy and tennis elbow are common examples of these conditions. Conventional treatments have shown inconsistent outcomes and might fail to provide satisfactory clinical improvement. With the growing trend towards the use of mesenchymal stem cells (MSCs in other branches of medicine, there is an increasing interest in treating tendon pathologies using the bone marrow MSC. In this article, we provide a systematic literature review documenting the current status of the use of bone marrow aspirate concentrate (BMAC for the treatment of tendon pathologies. We also asked the question on the safety of BMAC and whether there are potential complications associated with BMAC therapy. Our hypothesis is that the use of BMAC provides safe clinical benefit when used for the treatment of tendinopathy or as a biological augmentation of tendon repair. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA checklist while preparing this systematic review. A literature search was carried out including the online databases of PubMed, EMBASE, ClinicalTrial.gov and the Cochrane Library from 1960 to the end of May 2015. Relevant studies were selected and critically appraised. Data from eligible studies were extracted and classified per type of tendon pathology. We included 37 articles discussing the application and use of BMAC for the treatment of tendon pathologies. The Critical Appraisal Skills Program (CASP appraisal confirmed a satisfactory standard of 37 studies. Studies were sub-categorised into: techniques of extraction, processing and microscopic examination of BMAC (n = 18, where five studies looked at the evaluation of aspiration techniques (n = 5, augmentation of rotator cuff tears (n = 5

  6. Imaging and quantifying solute transport across periosteum: implications for muscle-bone crosstalk.

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    Lai, Xiaohan; Price, Christopher; Lu, Xin Lucas; Wang, Liyun

    2014-09-01

    Muscle and bone are known to act as a functional unit and communicate biochemically during tissue development and maintenance. Muscle-derived factors (myokines) have been found to affect bone functions in vitro. However, the transport times of myokines to penetrate into bone, a critical step required for local muscle-bone crosstalk, have not been quantified in situ or in vivo. In this study, we investigated the permeability of the periosteum, a major barrier to muscle-bone crosstalk by tracking and modeling fluorescent tracers that mimic myokines under confocal microscopy. Periosteal surface boundaries and tracer penetration within the boundaries were imaged in intact murine tibiae using reflected light and time-series xz confocal imaging, respectively. Four fluorescent tracers including sodium fluorescein (376Da) and dextrans (3kDa, 10kDa and 40kDa) were chosen because they represented a wide range of molecular weights (MW) of myokines. We found that i) murine periosteum was permeable to the three smaller tracers while the 40kDa could not penetrate beyond 40% of the outer periosteum within 8h, suggesting that periosteum is semi-permeable with a cut-off MW of approximately 40kDa, and ii) the characteristic penetration time through the periosteum (~60μm thick) increased with tracer MW and fit well with a relationship tcs=-4.43×10(4)-0.57×MWDa-4×10(4)-8.65×10(8)MWDa-4×10(4), from which, the characteristic penetration times of various myokines were extrapolated. To achieve effective muscle-bone crosstalk, likely signaling candidates should have shorter penetration time than their bioactive time, which we assumed to be 5 times of the molecule's half-lifetime in the body. Myokines such as PGE2, IGF-1, IL-15 and FGF-2 were predicted to satisfy this requirement. In summary, a novel imaging approach was developed and used to investigate the transport of myokine mimicking-tracers through the periosteum, enabling further quantitative studies of muscle-bone

  7. Biomechanical and immunohistochemical analysis of high hydrostatic pressure-treated Achilles tendons

    International Nuclear Information System (INIS)

    Diehl, P.; Steinhauser, E.; Gollwitzer, H.; Heister, C.; Schauwecker, J.; Schmitt, M.; Milz, S.; Mittelmeier, W.

    2006-01-01

    Reconstruction of bone defects caused by malignant tumors is carried out in different ways. At present, tumor-bearing bone segments are devitalized mainly by extracorporeal irradiation or autoclaving, but both methods have substantial disadvantages. In this regard, high hydrostatic pressure (HHP) treatment of the bone is a new, advancing technology that has been used in preclinical testing to inactivate normal cells and tumor cells without altering the biomechanical properties of the bone. The aim of this study was to examine the biomechanical and immunohistochemical properties of tendons after exposure to HHP and to evaluate whether preservation of the bony attachment of tendons and ligaments is possible. For this, 19 paired Achilles tendons were harvested from both hindlimbs of 4-month-old pigs. After preparation, the cross-sectional area of each tendon was determined by magnetic resonance imaging (MRI). For each animal, one of the two tendons was taken at random and exposed to a pressure of 300 MPa (n=9) or 600 MPa (n=10). The contralateral tendon served as an untreated control. The biomechanical properties of the tendons remained unchanged with respect to the tested parameters: Young's modulus (MPa) and tensile strength (MPa). This finding is in line with immunohistochemical labeling results, as no difference in the labeling pattern of collagen I and versican was observed when comparing the HHP group (at 600 MPa) to the untreated control group. We anticipate that during orthopedic surgery HHP can serve as a novel, promising methodical approach to inactivate Achilles tendon and bone cells without altering the biomechanical properties of the tendons. This should allow one to preserve the attachment of tendon and ligaments to the devitalized bone and to facilitate functional reconstruction. (author)

  8. Patient Satisfaction in the Treatment of Acute Hamstring Strain Injury

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    LingLing- Lai

    2014-05-01

    Full Text Available Introduction: The impact of musculoskeletal injuries often caused loss time in sport participation. Athletes who suffered from these injuries experienced a decrease in performance and physical disability. Although a variety of treatments have been implemented to the muscle injuries, the administration of autologous blood injection is replacing the conventional rehabilitation to expedite the process of muscle recovery. Platelet-rich plasma (PRP is relatively new in muscle injury treatment and there is lack of evidence of the satisfaction of PRP treatment in muscle injuries. Purposes: The study aimed to investigate the patient satisfaction in the administration of PRP treatment and rehabilitation program for acute hamstring strain injury. Methods: Participants (competitive, semi-competitive and recreational athletes with acute hamstring strain injury (Grade II were recruited. Participants were randomly divided into either the PRP treatment or rehabilitation program. Participants were required to attend weekly follow up assessment for recovery evaluation. All the participants were required to complete a patient satisfaction questionnaire (PSQ-18 at the end of study.  The questionnaire is divided into seven sub-scales: general satisfaction, technical quality, interpersonal manner, communication, financial aspect, time spent with doctor, accessibility and convenience. Results: Participants were 22.35 ± 3.41 years. Duration from injury to first presentation in clinic ranged from two to ten days. Mean duration of recovery was 5.64 weeks. No statistically significant difference in the patient satisfaction sub-scales score between the two groups (p>0.05. Conclusion: The present study demonstrates that PRP treatment is as satisfactory as conventional rehabilitation program in managing acute hamstring strain injury. Both  modalities are correspondingly safe and have high degree of satisfaction. Given the acceptable outcomes, patients are likely to

  9. Effect of altering starting length and activation timing of muscle on fiber strain and muscle damage.

    Science.gov (United States)

    Butterfield, Timothy A; Herzog, Walter

    2006-05-01

    Muscle strain injuries are some of the most frequent injuries in sports and command a great deal of attention in an effort to understand their etiology. These injuries may be the culmination of a series of subcellular events accumulated through repetitive lengthening (eccentric) contractions during exercise, and they may be influenced by a variety of variables including fiber strain magnitude, peak joint torque, and starting muscle length. To assess the influence of these variables on muscle injury magnitude in vivo, we measured fiber dynamics and joint torque production during repeated stretch-shortening cycles in the rabbit tibialis anterior muscle, at short and long muscle lengths, while varying the timing of activation before muscle stretch. We found that a muscle subjected to repeated stretch-shortening cycles of constant muscle-tendon unit excursion exhibits significantly different joint torque and fiber strains when the timing of activation or starting muscle length is changed. In particular, measures of fiber strain and muscle injury were significantly increased by altering activation timing and increasing the starting length of the muscle. However, we observed differential effects on peak joint torque during the cyclic stretch-shortening exercise, as increasing the starting length of the muscle did not increase torque production. We conclude that altering activation timing and muscle length before stretch may influence muscle injury by significantly increasing fiber strain magnitude and that fiber dynamics is a more important variable than muscle-tendon unit dynamics and torque production in influencing the magnitude of muscle injury.

  10. Triceps-surae musculotendinous stiffness: relative differences between obese and non-obese postmenopausal women.

    Science.gov (United States)

    Faria, Aurélio; Gabriel, Ronaldo; Abrantes, João; Brás, Rui; Moreira, Helena

    2009-12-01

    There is a lack of research into the relationship between obesity and muscle-tendon unit stiffness in postmenopausal women. Muscle-tendon unit stiffness appears to affect human motion performance and excessive and insufficient stiffness can increase the risk of bone and soft tissue injuries, respectively. The aim of this study was to investigate the relationship between muscle-tendon unit stiffness and obesity in postmenopausal women. 105 postmenopausal women (58 [SD 5.5] years) participated. Four groups (normal weight, pre-obese, obesity class I and obesity class II) were defined according World Health Organization classification of body mass index. The ankle muscle-tendon unit stiffness was assessed in vivo with a free oscillation technique using a load of 30% of maximal voluntary isometric contraction. ANOVA shows significant difference in muscle-tendon unit stiffness among the groups defined (Pnormal weight-pre-obese; normal weight-obesity class I and normal weight-obesity class II. The normal weight group had stiffness of 15789 (SD 2969) N/m, pre-obese of 19971 (SD 3678) N/m, obesity class I of 21435 (SD 4295) N/m, and obesity class II of 23497 (SD 1776) N/m. Obese subjects may have increased muscle-tendon unit stiffness because of fat infiltration in leg skeletal muscles, range of motion restrictions and stability/posture reasons and might be more predisposed to develop musculoskeletal injuries. Normal weight group had identical stiffness values to those reported in studies where subjects were not yet menopausal, suggesting that stiffness might not be influenced by menopause.

  11. Terrestrial applications of bone and muscle research in microgravity

    Science.gov (United States)

    Booth, F. W.

    1994-08-01

    Major applications to people on Earth are possible from NASA-sponsored research on bone and muscle which is conducted either in microgravity or on Earth using models mimicking microgravity. In microgravity bone and muscle mass are lost. Humans experience a similar loss under certain conditions on Earth. Bone and muscle loss exist on Earth as humans age from adulthood to senescence, during limb immobilization for healing of orthopedic injuries, during wheelchair confinement because of certain diseases, and during chronic bed rest prescribed for curing of diseases. NASA-sponsored research is dedicated to learning both what cause bone and muscle loss as well as finding out how to prevent this loss. The health ramifications of these discoveries will have major impact. Objective 1.6 of Healthy People 2000, a report from the U.S. Department of Health and Human Services, states that the performance of physical activities that improve muscular strength, muscular endurance, and flexibility is particularly important to maintaining functional independence and social integration in older adults /1/. This objective further states that these types of physical activities are important because they may protect against disability, an event which costs the U.S. economy hugh sums of money. Thus NASA research related to bone and muscle loss has potential major impact on the quality of life in the U.S. Relative to its potential health benefits, NASA and Congressional support of bone and muscle research is funded is a very low level.

  12. Heparin functionalization increases retention of TGF-β2 and GDF5 on biphasic silk fibroin scaffolds for tendon/ligament-to-bone tissue engineering.

    Science.gov (United States)

    Font Tellado, Sònia; Chiera, Silvia; Bonani, Walter; Poh, Patrina S P; Migliaresi, Claudio; Motta, Antonella; Balmayor, Elizabeth R; van Griensven, Martijn

    2018-05-01

    The tendon/ligament-to-bone transition (enthesis) is a highly specialized interphase tissue with structural gradients of extracellular matrix composition, collagen molecule alignment and mineralization. These structural features are essential for enthesis function, but are often not regenerated after injury. Tissue engineering is a promising strategy for enthesis repair. Engineering of complex tissue interphases such as the enthesis is likely to require a combination of biophysical, biological and chemical cues to achieve functional tissue regeneration. In this study, we cultured human primary adipose-derived mesenchymal stem cells (AdMCs) on biphasic silk fibroin scaffolds with integrated anisotropic (tendon/ligament-like) and isotropic (bone/cartilage like) pore alignment. We functionalized those scaffolds with heparin and explored their ability to deliver transforming growth factor β2 (TGF-β2) and growth/differentiation factor 5 (GDF5). Heparin functionalization increased the amount of TGF-β2 and GDF5 remaining attached to the scaffold matrix and resulted in biological effects at low growth factor doses. We analyzed the combined impact of pore alignment and growth factors on AdMSCs. TGF-β2 and pore anisotropy synergistically increased the expression of tendon/ligament markers and collagen I protein content. In addition, the combined delivery of TGF-β2 and GDF5 enhanced the expression of cartilage markers and collagen II protein content on substrates with isotropic porosity, whereas enthesis markers were enhanced in areas of mixed anisotropic/isotropic porosity. Altogether, the data obtained in this study improves current understanding on the combined effects of biological and structural cues on stem cell fate and presents a promising strategy for tendon/ligament-to-bone regeneration. Regeneration of the tendon/ligament-to-bone interphase (enthesis) is of significance in the repair of ruptured tendons/ligaments to bone to improve implant integration and

  13. CONTRIBUTION OF HAMSTRING FATIGUE TO QUADRICEPS INHIBITION FOLLOWING LUMBAR EXTENSION EXERCISE

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    Joseph M. Hart

    2006-03-01

    Full Text Available The purpose of this study was to determine the contribution of hamstrings and quadriceps fatigue to quadriceps inhibition following lumbar extension exercise. Regression models were calculated consisting of the outcome variable: quadriceps inhibition and predictor variables: change in EMG median frequency in the quadriceps and hamstrings during lumbar fatiguing exercise. Twenty-five subjects with a history of low back pain were matched by gender, height and mass to 25 healthy controls. Subjects performed two sets of fatiguing isometric lumbar extension exercise until mild (set 1 and moderate (set 2 fatigue of the lumbar paraspinals. Quadriceps and hamstring EMG median frequency were measured while subjects performed fatiguing exercise. A burst of electrical stimuli was superimposed while subjects performed an isometric maximal quadriceps contraction to estimate quadriceps inhibition after each exercise set. Results indicate the change in hamstring median frequency explained variance in quadriceps inhibition following the exercise sets in the history of low back pain group only. Change in quadriceps median frequency explained variance in quadriceps inhibition following the first exercise set in the control group only. In conclusion, persons with a history of low back pain whose quadriceps become inhibited following lumbar paraspinal exercise may be adapting to the fatigue by using their hamstring muscles more than controls

  14. Is there really an eccentric action of the hamstrings during the swing phase of high-speed running? Part II: Implications for exercise.

    Science.gov (United States)

    Van Hooren, Bas; Bosch, Frans

    2017-12-01

    We have previously argued that there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstring muscle fibres during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this we suggested that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running. In this review we argue that some of the presumed beneficial adaptations following eccentric training may actually not be related to the eccentric muscle fibre action, but to other factors such as exercise intensity. Furthermore, we discuss several disadvantages associated with commonly used eccentric hamstring exercises. Subsequently, we argue that high-intensity isometric exercises in which the series elastic element stretches and recoils may be equally or even more effective at conditioning the hamstrings for high-speed running, since they also avoid some of the negative side effects associated with eccentric training. We provide several criteria that exercises should fulfil to effectively condition the hamstrings for high-speed running. Adherence to these criteria will guarantee specificity with regards to hamstrings functioning during running. Practical examples of isometric exercises that likely meet several criteria are provided.

  15. EFFECT OF UNIPOLAR ACU-STIM ON MUSCLE RE-EDUCATION FOLLOWING TENDON TRANSFER - A CASE STUDY

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    Prof. Srikanth R

    2015-02-01

    Full Text Available Background: Tendon transfer surgery is usually done to improve function, following damage to either major nerve trunks or peripheral nerves. Re-education of the muscle is of utmost importance to gain functional activity.To achieve this, along with re-education exercises, faradic stimulation is usually used. Unipolar Acu-Stim (UAS, is an innovative technique where an acupuncture needle is used to stimulate the transferred tendon with Surged Faradic Currents (SFC. The objective of the study is to identify if the application of SFC using UAS method, is effective to re-educate a transferred muscle. Case Description: The subject was a 24 year old male who had a loss of finger and thumb extension following Posterior Interosseous Nerve (PIN palsy, for which Flexor Carpi Radialis (FCR was transferred to Extensor Digitorum Communis (EDC and Palmaris Longus (PL was transferred to Extensor Pollicis Longus (EPL. Following removal of the POP, UAS with surged faradic current was applied for 4 weeks along with re-education exercises. Prognosis of finger extension was assessed by goniometry and video recordings. Outcome: At the end of 8th week, as observed on goniometry and video recordings, complete finger extension was achieved. Discussion: UAS with SFC, is useful in re-education of a transferred muscle, as desired movement can be achieved with low intensity.

  16. Muscle changes can account for bone loss after botulinum toxin injection.

    Science.gov (United States)

    Manske, Sarah L; Boyd, Steven K; Zernicke, Ronald F

    2010-12-01

    Studies to date have assumed that botulinum toxin type A (BTX) affects bone indirectly, through its action on muscle. We hypothesized that BTX has no discernable effect on bone morphometry, independent of its effect on muscle. Therefore, we investigated whether BTX had an additional effect on bone when combined with tenotomy compared to tenotomy in isolation. Female BALB/c mice (n = 73) underwent one of the following procedures in the left leg: BTX injection and Achilles tenotomy (BTX-TEN), BTX injection and sham surgery (BTX-sham), Achilles tenotomy (TEN), or sham surgery (sham). BTX groups were injected with 20 μL of BTX (1 U/100 g) in the posterior lower hindlimb. At 4 weeks, muscle cross-sectional area (MCSA) and tibial bone morphometry were assessed using micro-CT. Each treatment, other than sham, resulted in significant muscle and bone loss (P properties. We found that BTX injection resulted in more adverse muscle and bone effects than tenotomy and that effects were amplified when the procedures were combined. However, between-group differences in bone could be accounted for by MCSA. We conclude that any independent effect of BTX on bone morphometry is likely small or negligible compared with the effect on muscle.

  17. Flexor digitorum profundus tendon anatomy in the forearm

    Directory of Open Access Journals (Sweden)

    Teoman Dogan

    2012-04-01

    Methods: We used 11 forearms belonging to cadavers and fixed with formaldehyde. The forearms numbered 1, 2, 8, 9, 10, 11 were the left and right arms of the same cadavers. Those numbered 3, 4, 5, 6, 7 belonged to different cadavers. Dissections were made by using the atraumatic surgical technique. The tendons were studied to identify the structure and number of the fibers forming them. Results: The presence of a large common tendon was found in 10 of the 11 forearms. In 4 of these, the common tendon included the tendons of all four fingers. While the common tendon included 3 fingers in four forearms, it only included tendons belonging to 2 fingers in two forearms. It was not possible in one forearm to separate the common tendon into its fibers. In another forearm, tendons belonging to each digit were separate and independent starting at the muscle-tendon junction to the attachment points. Conclusion: The majority of the cadaver forearms used in the study displayed a single large FDP tendon in the zone between the muscle-tendon joint to the carpal tunnel entry prior to being distributed into each index. This anatomical feature should be considered in choosing materials and surgical technique for Zone V FDP tendon injuries, as well as in planning the rehabilitation process. [Hand Microsurg 2012; 1(1.000: 25-29

  18. INFLUENCE OF TWO DIFFERENT SITTING POSTURES ON HAMSTRING MUSCLE FLEXIBILITY IN SCHOOL GOING CHILDREN

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    Vadivelan .K

    2015-04-01

    Full Text Available Background: Children adopting different styles of sitting in class rooms may have an influence over the hamstring length which indirectly produces an effect on posture, gait and musculoskeletal problems. Hence, physiotherapists play an important role in preventing the problems that are to be developed due to the sitting posture adopted at school. Hence, it is important for all the health professionals to understand and know about the effect of different sitting styles of children in school over the children health.The purpose of this study was to determine the influence of two sitting postures (crossed leg sitting and bench sitting on hamstring flexibility in school going children. Aim of the Study to observe the influence of bench sitting and crossed-leg sitting on hamstring flexibility in school going children. Methods: 200 school children (105 boys and 95 girls from private schools (those who are bench sitting and 200 school children (109 boys and 91 girls from government schools (those who are crossed leg sitting aged 6-10 years were included in this study. Active Knee Extension (AKE test with the aid of a simple and economically cheap stabilizing apparatus was used to determine hamstring flexibility. Measurements were taken for both right and left knee. Results: The mean Active Knee Extension (AKE score for bench sitting children was 132.4 and for crossed leg sitting children was 130.1. The difference observed in knee extension range of motion between the groups was statistically significant (p<0.05. Conclusion: Hamstring flexibility was greater in bench sitting children as compared to crossed leg sitting children.

  19. A COMPARATIVE STUDY ON EFFECTIVENESS OF STATIC STRETCH AND HOLD RELAX TECHNIQUES OVER HAMSTRING FLEXIBILITY

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    N. Vamsidhar

    2014-12-01

    Full Text Available Background: Flexibility is important in prevention of injury, muscular and postural imbalance more over the Hamstring flexibility has a lion share in sports performances and preventing DOMS. Stretching procedures increases the ROM by embarking on biomechanics and Neurologic and molecular mechanics. Hamstrings, the two joint muscle plays a crucial role in two joints integrity and also spine as they are in closed kinematic chain. The hamstring muscles represent the primary flexors of Knee. Hamstrings tightness results in Limits Knee extension when hip is flexed, Posterior Pelvic tilt, and flatten the lumbar spine. Methods: The subjects selected randomly and divided into two groups (Experimental group and control group.30 samples in One group applied with Static Stretch once a day for 3 repetitions 5 days a week for six weeks and 30 samples in other group applied with Hold relax technique once a day for 4 repetitions 5 days a week for six weeks. The knee joint range of motion was measured at the end of every week with Universal goniometer. Results: By comparing the means of Group – I, given Static Stretch and Group – II, given Hold relax Technique for six weeks implied that there is improvement of flexibility in Group – II and the ‘P’ value < 0.01 shows the difference is highly significant. Conclusion: This study concludes that the hold relax Technique method has proved to be better technique then the static stretch for improving hamstring flexibility.

  20. Comparison of the large muscle group widths of the pelvic limb in seven breeds of dogs.

    Science.gov (United States)

    Sabanci, Seyyid Said; Ocal, Mehmet Kamil

    2018-05-14

    Orthopaedic diseases are common in the pelvic limbs of dogs, and reference values for large muscle groups of the pelvic limb may aid in diagnosis such diseases. As such, the objective of this study was to compare the large muscle groups of the pelvic limb in seven breeds of dogs. A total of 126 dogs from different breeds were included, and the widths of the quadriceps, hamstring and gastrocnemius muscles were measured from images of the lateral radiographies. The width of the quadriceps was not different between the breeds, but the widths of the hamstring and gastrocnemius muscles were significantly different between the breeds. The widest hamstring and gastrocnemius muscles were seen in the Rottweilers and the Boxers, respectively. The narrowest hamstring and gastrocnemius muscles were seen in the Belgian Malinois and the Golden retrievers, respectively. All ratios between the measured muscles differed significantly between the breeds. Doberman pinschers and Belgian Malinois had the highest ratio of gastrocnemius width:hamstring width. Doberman pinschers had also the highest ratio of quadriceps width:hamstring width. German shepherds had the highest ratio of gastrocnemius width:quadriceps width. The lowest ratios of quadriceps width:hamstring width were determined in the German shepherds. The ratios of the muscle widths may be used as reference values to assess muscular atrophy or hypertrophy in cases of bilateral or unilateral orthopaedic diseases of the pelvic limbs. Further studies are required to determine the widths and ratios of the large muscle groups of the pelvic limbs in other dog breeds. © 2018 Blackwell Verlag GmbH.

  1. The clinical anatomy of the insertion of the rotator cuff tendons.

    Science.gov (United States)

    Vosloo, M; Keough, N; De Beer, M A

    2017-04-01

    The rotator cuff (RC) insertions according to most anatomical texts are described as being separate from one another. However, clear fusion of the RC tendon fibres exists with prior studies showing this interdigitation forming a common, continuous insertion onto and around the lesser and greater tubercles (LT and GT) of the humerus. Current surgical repair methods (especially arthroscopic techniques) rarely mention or consider these connections during repair and suture anchor implantation. The general principles of RC surgery remain a controversial subject, due to various available techniques, surgeon experience and preference, and the contradicting success rates. This results from old-fashioned knowledge of the anatomy of the RC complex and its functional aspects. Therefore, the purpose of this project was to visualise and define the RC footprint and extension insertions with the aim of enhancing and improving knowledge of the basic anatomy in the hopes that this will be considered during orthopaedic repair. Twenty shoulders (16 cadaveric and 4 fresh) were used in the study. The fresh shoulders were received from the National Tissue Bank, and ethical clearance was obtained (239/2015). Reverse dissection was performed to better visualise the RC unit exposing the interdigitated rotator hood (extension insertions), as well as the complete RC unit (tendons + internal capsule) separated from the scapula and humerus. Once the insertions were exposed and documented, the RC muscle footprint (articular surface area) was measured and recorded, using AutoCAD 2016. No statistical significant difference between left and right (p = 0.424) was noted, but a significant difference between males and females (p = 0.000) was. Collectively, these findings indicate and strengthen evidence towards the notion that the RC muscles/tendons and the internal capsule are one complete and inseparable unit/complex. The fact that the RC unit is more complex in its structure and attachment

  2. History-dependence of muscle slack length following contraction and stretch in the human vastus lateralis.

    Science.gov (United States)

    Stubbs, Peter W; Walsh, Lee D; D'Souza, Arkiev; Héroux, Martin E; Bolsterlee, Bart; Gandevia, Simon C; Herbert, Robert D

    2018-06-01

    In reduced muscle preparations, the slack length and passive stiffness of muscle fibres have been shown to be influenced by previous muscle contraction or stretch. In human muscles, such behaviours have been inferred from measures of muscle force, joint stiffness and reflex magnitudes and latencies. Using ultrasound imaging, we directly observed that isometric contraction of the vastus lateralis muscle at short lengths reduces the slack lengths of the muscle-tendon unit and muscle fascicles. The effect is apparent 60 s after the contraction. These observations imply that muscle contraction at short lengths causes the formation of bonds which reduce the effective length of structures that generate passive tension in muscles. In reduced muscle preparations, stretch and muscle contraction change the properties of relaxed muscle fibres. In humans, effects of stretch and contraction on properties of relaxed muscles have been inferred from measurements of time taken to develop force, joint stiffness and reflex latencies. The current study used ultrasound imaging to directly observe the effects of stretch and contraction on muscle-tendon slack length and fascicle slack length of the human vastus lateralis muscle in vivo. The muscle was conditioned by (a) strong isometric contractions at long muscle-tendon lengths, (b) strong isometric contractions at short muscle-tendon lengths, (c) weak isometric contractions at long muscle-tendon lengths and (d) slow stretches. One minute after conditioning, ultrasound images were acquired from the relaxed muscle as it was slowly lengthened through its physiological range. The ultrasound image sequences were used to identify muscle-tendon slack angles and fascicle slack lengths. Contraction at short muscle-tendon lengths caused a mean 13.5 degree (95% CI 11.8-15.0 degree) shift in the muscle-tendon slack angle towards shorter muscle-tendon lengths, and a mean 5 mm (95% CI 2-8 mm) reduction in fascicle slack length, compared to the

  3. Tendon injury and repair - A perspective on the basic mechanisms of tendon disease and future clinical therapy

    NARCIS (Netherlands)

    Snedeker, J.G.; Foolen, J.

    2017-01-01

    Tendon is an intricately organized connective tissue that efficiently transfers muscle force to the bony skeleton. Its structure, function, and physiology reflect the extreme, repetitive mechanical stresses that tendon tissues bear. These mechanical demands also lie beneath high clinical rates of

  4. Differences in hamstring activation characteristics between the acceleration and maximum-speed phases of sprinting.

    Science.gov (United States)

    Higashihara, Ayako; Nagano, Yasuharu; Ono, Takashi; Fukubayashi, Toru

    2018-06-01

    This study aimed to investigate activation characteristics of the biceps femoris long head (BFlh) and semitendinosus (ST) muscles during the acceleration and maximum-speed phases of sprinting. Lower-extremity kinematics and electromyographic (EMG) activities of the BFlh and ST muscles were examined during the acceleration sprint and maximum-speed sprint in 13 male sprinters during an overground sprinting. Differences in hamstring activation during each divided phases and in the hip and knee joint angles and torques at each time point of the sprinting gait cycle were determined between two sprints. During the early stance of the acceleration sprint, the hip extension torque was significantly greater than during the maximum-speed sprint, and the relative EMG activation of the BFlh muscle was significantly higher than that of the ST muscle. During the late stance and terminal mid-swing of maximum-speed sprint, the knee was more extended and a higher knee flexion moment was observed compared to the acceleration sprint, and the ST muscle showed higher activation than that of the BFlh. These results indicate that the functional demands of the medial and lateral hamstring muscles differ between two different sprint performances.

  5. Hamstring injuries: update article

    Directory of Open Access Journals (Sweden)

    Lucio Ernlund

    Full Text Available ABSTRACT Hamstring (HS muscle injuries are the most common injury in sports. They are correlated to long rehabilitations and have a great tendency to recur. The HS consist of the long head of the biceps femoris, semitendinosus, and semimembranosus. The patient's clinical presentation depends on the characteristics of the lesion, which may vary from strain to avulsions of the proximal insertion. The most recognized risk factor is a previous injury. Magnetic resonance imaging is the method of choice for the injury diagnosis and classification. Many classification systems have been proposed; the current classifications aim to describe the injury and correlate it to the prognosis. The treatment is conservative, with the use of anti-inflammatory drugs in the acute phase followed by a muscle rehabilitation program. Proximal avulsions have shown better results with surgical repair. When the patient is pain free, shows recovery of strength and muscle flexibility, and can perform the sport's movements, he/she is able to return to play. Prevention programs based on eccentric strengthening of the muscles have been indicated both to prevent the initial injury as well as preventing recurrence.

  6. Peak medial (but not lateral) hamstring activity is significantly lower during stance phase of running. An EMG investigation using a reduced gravity treadmill.

    Science.gov (United States)

    Hansen, Clint; Einarson, Einar; Thomson, Athol; Whiteley, Rodney

    2017-09-01

    The hamstrings are seen to work during late swing phase (presumably to decelerate the extending shank) then during stance phase (presumably stabilizing the knee and contributing to horizontal force production during propulsion) of running. A better understanding of this hamstring activation during running may contribute to injury prevention and performance enhancement (targeting the specific role via specific contraction mode). Twenty active adult males underwent surface EMG recordings of their medial and lateral hamstrings while running on a reduced gravity treadmill. Participants underwent 36 different conditions for combinations of 50%-100% altering bodyweight (10% increments) & 6-16km/h (2km/h increments, i.e.: 36 conditions) for a minimum of 6 strides of each leg (maximum 32). EMG was normalized to the peak value seen for each individual during any stride in any trial to describe relative activation levels during gait. Increasing running speed effected greater increases in EMG for all muscles than did altering bodyweight. Peak EMG for the lateral hamstrings during running trials was similar for both swing and stance phase whereas the medial hamstrings showed an approximate 20% reduction during stance compared to swing phase. It is suggested that the lateral hamstrings work equally hard during swing and stance phase however the medial hamstrings are loaded slightly less every stance phase. Likely this helps explain the higher incidence of lateral hamstring injury. Hamstring injury prevention and rehabilitation programs incorporating running should consider running speed as more potent stimulus for increasing hamstring muscle activation than impact loading. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Ontogeny of the Alligator Cartilago Transiliens and Its Significance for Sauropsid Jaw Muscle Evolution

    Science.gov (United States)

    Tsai, Henry P.; Holliday, Casey M.

    2011-01-01

    The cartilago transiliens is a fibrocartilaginous structure within the jaw muscles of crocodylians. The cartilago transiliens slides between the pterygoid buttress and coronoid region of the lower jaw and connects two muscles historically identified as m. pseudotemporalis superficialis and m. intramandibularis. However, the position of cartilago transiliens, and its anatomical similarities to tendon organs suggest the structure may be a sesamoid linking a single muscle. Incompressible sesamoids often form inside tendons that wrap around bone. However, such structures rarely ossify in reptiles and have thus far received scant attention. We tested the hypothesis that the cartilago transiliens is a sesamoid developed within in one muscle by investigating its structure in an ontogenetic series of Alligator mississippiensis using dissection, 3D imaging, and polarizing and standard light microscopy. In all animals studied, the cartilago transiliens receives collagen fibers and tendon insertions from its two main muscular attachments. However, whereas collagen fibers were continuous within the cartilaginous nodule of younger animals, such continuity decreased in older animals, where the fibrocartilaginous core grew to displace the fibrous region. Whereas several neighboring muscles attached to the fibrous capsule in older individuals, only two muscles had significant contributions to the structure in young animals. Our results indicate that the cartilago transiliens is likely a sesamoid formed within a single muscle (i.e., m. pseudotemporalis superficialis) as it wraps around the pterygoid buttress. This tendon organ is ubiquitous among fossil crocodyliforms indicating it is a relatively ancient, conserved structure associated with the development of the large pterygoid flanges in this clade. Finally, these findings indicate that similar tendon organs exist among potentially homologous muscle groups in birds and turtles, thus impacting inferences of jaw muscle homology

  8. Biochemical Interaction Between Muscle and Bone: A Physiological Reality?

    NARCIS (Netherlands)

    Jaspers, R.T.; Bravenboer, N.

    2014-01-01

    In elderly with a sedentary lifestyle, often suffering from sarcopenia to osteopenia, a training intervention could be an effective countermeasure for bone as well as muscle. Both bone and muscle adapt their mass and strength in response to mechanical loading in part via similar signaling pathways.

  9. Over-the-top ACL Reconstruction Plus Extra-articular Lateral Tenodesis With Hamstring Tendon Grafts: Prospective Evaluation With 20-Year Minimum Follow-up.

    Science.gov (United States)

    Zaffagnini, Stefano; Marcheggiani Muccioli, Giulio Maria; Grassi, Alberto; Roberti di Sarsina, Tommaso; Raggi, Federico; Signorelli, Cecilia; Urrizola, Francisco; Spinnato, Paolo; Rimondi, Eugenio; Marcacci, Maurilio

    2017-12-01

    There are few published studies with very long-term follow-up of combined intra- and extra-articular anterior cruciate ligament (ACL) reconstruction. To analyze clinical and radiographic outcomes of over-the-top ACL reconstruction plus extra-articular lateral tenodesis with autologous hamstrings at minimum 20-year follow-up. Case series; Level of evidence, 4. Of 60 originally eligible patients who underwent over-the-top ACL reconstruction with double-stranded hamstring tendon (leaving intact graft tibial insertions) and extra-articular lateral plasty (performed with the remnant part of tendons), 52 were prospectively evaluated at a minimum 20-year follow-up (mean follow-up, 24 years; 41 men, 11 women; mean age at time of surgery, 25.5 ± 7.6 years). Twenty-nine patients were available for prospective evaluations: clinical (Lysholm, Tegner, and objective International Knee Documentation Committee [IKDC]), instrumented (KT-2000), and radiographic (standard, long-standing, and Merchant views). Subjective KOOS (Knee injury and Osteoarthritis Outcome Score) and objective inertial sensor pivot-shift analysis (KiRA) were carried out at final follow-up. Twenty-three patients were investigated by phone interview for subjective Tegner score and documented complications, rerupture, or revision surgery. At final follow-up, mean Lysholm score was 85.7 ± 14.6; median Tegner score, 4 (range, 3-5); sport activity resumption, 86.2%; and objective IKDC score, good or excellent in 86% of patients (31%, A; 55%, B). Only 3 of 26 patients (12%) had >5-mm manual maximum KT-2000 side-to-side difference. KiRA system documented positive pivot-shift (>0.9-m/s 2 tibial acceleration side-to-side difference) in these 3 of 26 patients (12%). Statistically significant changes were as follows: decrease in Tegner score from 7 (range, 6-8) at 5-year follow-up to 4 (range, 3-5) at 10 years ( P < .0001) and decrease in Lysholm score from 96.1 ± 7.3 at 10-year follow-up to 85.7 ± 14.6 at 20 years

  10. Effect of tendon vibration during wide-pulse neuromuscular electrical stimulation (NMES) on muscle force production in people with spinal cord injury (SCI).

    Science.gov (United States)

    Bochkezanian, Vanesa; Newton, Robert U; Trajano, Gabriel S; Vieira, Amilton; Pulverenti, Timothy S; Blazevich, Anthony J

    2018-02-13

    Neuromuscular electrical stimulation (NMES) is commonly used in skeletal muscles in people with spinal cord injury (SCI) with the aim of increasing muscle recruitment and thus muscle force production. NMES has been conventionally used in clinical practice as functional electrical stimulation (FES), using low levels of evoked force that cannot optimally stimulate muscular strength and mass improvements, and thus trigger musculoskeletal changes in paralysed muscles. The use of high intensity intermittent NMES training using wide-pulse width and moderate-intensity as a strength training tool could be a promising method to increase muscle force production in people with SCI. However, this type of protocol has not been clinically adopted because it may generate rapid muscle fatigue and thus prevent the performance of repeated high-intensity muscular contractions in paralysed muscles. Moreover, superimposing patellar tendon vibration onto the wide-pulse width NMES has been shown to elicit further increases in impulse or, at least, reduce the rate of fatigue in repeated contractions in able-bodied populations, but there is a lack of evidence to support this argument in people with SCI. Nine people with SCI received two NMES protocols with and without superimposing patellar tendon vibration on different days (i.e. STIM and STIM+vib), which consisted of repeated 30 Hz trains of 58 wide-pulse width (1000 μs) symmetric biphasic pulses (0.033-s inter-pulse interval; 2 s stimulation train; 2-s inter-train interval) being delivered to the dominant quadriceps femoris. Starting torque was 20% of maximal doublet-twitch torque and stimulations continued until torque declined to 50% of the starting torque. Total knee extensor impulse was calculated as the primary outcome variable. Total knee extensor impulse increased in four subjects when patellar tendon vibration was imposed (59.2 ± 15.8%) but decreased in five subjects (- 31.3 ± 25.7%). However, there were no

  11. Deviating running kinematics and hamstring injury susceptibility in male soccer players: Cause or consequence?

    Science.gov (United States)

    Schuermans, Joke; Van Tiggelen, Damien; Palmans, Tanneke; Danneels, Lieven; Witvrouw, Erik

    2017-09-01

    Although the vast majority of hamstring injuries in male soccer are sustained during high speed running, the association between sprinting kinematics and hamstring injury vulnerability has never been investigated prospectively in a cohort at risk. This study aimed to objectify the importance of lower limb and trunk kinematics during full sprint in hamstring injury susceptibility. Cohort study; level of evidence, 2. At the end of the 2013 soccer season, three-dimensional kinematic data of the lower limb and trunk were collected during sprinting in a cohort consisting of 30 soccer players with a recent history of hamstring injury and 30 matched controls. Subsequently, a 1.5 season follow up was conducted for (re)injury registry. Ultimately, joint and segment motion patterns were submitted to retro- and prospective statistical curve analyses for injury risk prediction. Statistical analysis revealed that index injury occurrence was associated with higher levels of anterior pelvic tilting and thoracic side bending throughout the airborne (swing) phases of sprinting, whereas no kinematic differences during running were found when comparing players with a recent hamstring injury history with their matched controls. Deficient core stability, enabling excessive pelvis and trunk motion during swing, probably increases the primary injury risk. Although sprinting encompasses a relative risk of hamstring muscle failure in every athlete, running coordination demonstrated to be essential in hamstring injury prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Effects of hamstring stretch with pelvic control on pain and work ability in standing workers.

    Science.gov (United States)

    Han, Hyun-Il; Choi, Ho-Suk; Shin, Won-Seob

    2016-11-21

    Hamstring tightness induces posterior pelvic tilt and decreased lumbar lordosis, which can result in low back painOBJECTIVE: We investigated effects of hamstring stretch with pelvic control on pain and work ability in standing workers. One hundred adult volunteers from a standing workers were randomly assigned to pelvic control hamstring stretching (PCHS) (n = 34), general hamstring stretching (GHS) (n = 34), control (n = 32) groups. The control group was performed self-home exercise. All interventions were conducted 3 days per week for 6 weeks, and included in the hamstring stretching and lumbopelvic muscle strengthening. Outcomes were evaluated through the visual analog scale (VAS), straight leg raise test (SLR), sit and reach test (SRT), Oswestry disability index (ODI), and work ability index (WAI). Significant difference in VAS, SLR, SRT, ODI, and WAI were found in the PCHS and GHS groups. The control group was a significant difference only in ODI. The PCHS group showed a greater difference than the GHS group and control group in VAS, SLR, SRT, and ODI. The pelvic control hamstring stretch exercise would be more helpful in back pain reduction and improvement of work ability in an industrial setting.

  13. Discussion about different cut-off values of conventional hamstring-to-quadriceps ratio used in hamstring injury prediction among professional male football players.

    Science.gov (United States)

    Grygorowicz, Monika; Michałowska, Martyna; Walczak, Tomasz; Owen, Adam; Grabski, Jakub Krzysztof; Pyda, Andrzej; Piontek, Tomasz; Kotwicki, Tomasz

    2017-01-01

    To measure the sensitivity and specificity of differences cut-off values for isokinetic Hcon/Qcon ratio in order to improve the capacity to evaluate (retrospectively) the injury of hamstring muscles in professional soccer screened with knee isokinetic tests. Retrospective study. Medical and biomechanical data of professional football players playing for the same team for at least one season between 2010 and 2016 were analysed. Hamstring strain injury cases and the reports generated via isokinetic testing were investigated. Isokinetic concentric(con) hamstring(H) and quadriceps(Q) absolute strength in addition with Hcon/Qcon ratio were examined for the injured versus uninjured limbs among injured players, and for the injured and non-injured players. 2 x 2 contingency table was used for comparing variables: predicted injured or predicted uninjured with actual injured or actual uninjured. Sensitivity, specificity, accuracy, positive and negative predictive values, and positive and negative likelihood ratio were calculated for three different cut-off values (0.47 vs. 0.6 vs. 0.658) to compare the discriminative power of an isokinetic test, whilst examining the key value of Hcon/Qcon ratio which may indicate the highest level of ability to predispose a player to injury. McNemar's chi2 test with Yates's correction was used to determine agreement between the tests. PQStat software was used for all statistical analysis, and an alpha level of p hamstring injuries during the analysed period. None of these players sustained recurrence of hamstring injury. One player sustained hamstring strain injury on both legs, thus the total number of injuries was 12. Application of different cut-off values for Hcon/Qcon significantly affected the sensitivity and specificity of isokinetic test used as a tool for muscle injury detection. The use of 0.47 of Hcon/Qcon as a discriminate value resulted in significantly lower sensitivity when compared to 0.658 threshold (sensitivity of 16.7% vs

  14. Improved Achilles tendon healing by early mechanical loading in a rabbit model.

    Science.gov (United States)

    Wang, Jihong; Jiang, Dianming; Wen, Shuzheng; Jing, Shangfei; Fan, Dongsheng; Hao, Zengtao; Han, Chaoqian

    2015-01-01

    To investigate the structure and the attachment strength of a healing tendon-bone interface and the role of mechanical loading in tendon healing. Sixty rabbits underwent unilateral detachment and repair of the Achilles tendon. Thirty animals were immobilized (Group A), and the others wereallowed loadingimmediately postoperatively (Group B). Animals were sacrificed at 4 weeks and evaluated for histological and biomechanical testing. Statistical analysis was performed with an independent t test with significance set at P = 0.05. The ultimate stress was greater in group B (4.598 ± 1.321 N/mm(2)) compared with the control group (3.388 ± 0.994 N/mm(2)) (P tendon-to-bone interface with a larger area of chondrocytes was found in group B (P tendon-to-bone interface.

  15. [Reconstruction of the extensor pollicis longus tendon by transposition of the extensor indicis tendon].

    Science.gov (United States)

    Loos, A; Kalb, K; Van Schoonhoven, J; Landsleitner Dagger, B

    2003-12-01

    Rupture of the extensor pollicis longus-tendon (EPL) is a frequent complication after distal radius fractures. Other traumatic and non-traumatic reasons for this tendon lesion are known, including a theory about a disorder in the blood supply to the tendon itself. We examined 40 patients after reconstruction of the EPL-tendon in a mean follow-up time of 30 months. All patients were clinically examined and a DASH questionnaire was answered by all patients. The method to reconstruct the EPL-tendon was the transposition of the extensor indicis-tendon. After the operations the thumb was put in a splint for four weeks in a "hitch-hiker's-position". 31 ruptures of the tendon (77.5 %) were a result of trauma. In 20 of them (50 %) a distal radius fracture had occurred. Clinical examination included measurements of the movement of the thumb- and index-finger joints, the grip strength and the maximal span of the hand. Significant differences were not found. The isolated extension of the index finger was possible in all patients. But it was reduced in ten cases which represent 25 %. Our results were evaluated by the Geldmacher score to evaluate the reconstruction of the EPL-tendon. 20 % excellent, 65 % good, 12.5 % fair and 2.5 % poor results were reached. The Geldmacher score was used critically. We suggest its modification for the evaluation of thumb abduction. The DASH score reached a functional value of ten points which represents a very good result. In conclusion the extensor indicis-transposition is a safe method to reconstruct the EPL-tendon. Its substantial advantage is taking a healthy muscle as the motor, thereby avoiding the risk of using a degenerated muscle in late tendon reconstruction. A powerful extension of the index finger will be maintained by physical education. Generally, the loss of the extension of the index finger is negligible. It does not disturb the patients. But it has to be discussed with the patient before the operation.

  16. Associations of muscle force, power, cross-sectional muscle area and bone geometry in older UK men.

    Science.gov (United States)

    Zengin, Ayse; Pye, Stephen R; Cook, Michael J; Adams, Judith E; Rawer, Rainer; Wu, Frederick C W; O'Neill, Terence W; Ward, Kate A

    2017-08-01

    Ageing is associated with sarcopenia, osteoporosis, and increased fall risk, all of which contribute to increased fracture risk. Mechanically, bone strength adapts in response to forces created by muscle contractions. Adaptations can be through changes in bone size, geometry, and bending strength. Muscle mass is often used as a surrogate for muscle force; however, force can be increased without changes in muscle mass. Increased fall risk with ageing has been associated with a decline in muscle power-which is a measure of mobility. The aims of this study were as follows: (i) to investigate the relationship between muscle parameters in the upper and lower limbs with age in UK men and the influence of ethnicity on these relationships; (ii) to examine the relationships between jump force/grip strength/cross-sectional muscle area (CSMA) with bone outcomes at the radius and tibia. White European, Black Afro-Caribbean, and South Asian men aged 40-79 years were recruited from Manchester, UK. Cortical bone mineral content, cross-sectional area, cortical area, cross-sectional moment of inertia, and CSMA were measured at the diaphysis of the radius and tibia using peripheral quantitative computed tomography. Lower limb jump force and power were measured from a single two-legged jump performed on a ground-reaction force platform. Grip strength was measured using a dynamometer. Associations between muscle and bone outcomes was determined using linear regression with adjustments for age, height, weight, and ethnicity. Three hundred and one men were recruited. Jump force was negatively associated with age; for every 10 year increase in age, there was a 4% reduction in jump force (P force was positively associated with tibial bone outcomes: a 1 standard deviation greater jump force was associated with significantly higher cortical bone mineral content 3.1%, cross-sectional area 4.2%, cortical area 3.4%, and cross-sectional moment of inertia 6.8% (all P force and power are

  17. Non-myogenic Contribution to Muscle Development and Homeostasis: The Role of Connective Tissues.

    Science.gov (United States)

    Nassari, Sonya; Duprez, Delphine; Fournier-Thibault, Claire

    2017-01-01

    Skeletal muscles belong to the musculoskeletal system, which is composed of bone, tendon, ligament and irregular connective tissue, and closely associated with motor nerves and blood vessels. The intrinsic molecular signals regulating myogenesis have been extensively investigated. However, muscle development, homeostasis and regeneration require interactions with surrounding tissues and the cellular and molecular aspects of this dialogue have not been completely elucidated. During development and adult life, myogenic cells are closely associated with the different types of connective tissue. Connective tissues are defined as specialized (bone and cartilage), dense regular (tendon and ligament) and dense irregular connective tissue. The role of connective tissue in muscle morphogenesis has been investigated, thanks to the identification of transcription factors that characterize the different types of connective tissues. Here, we review the development of the various connective tissues in the context of the musculoskeletal system and highlight their important role in delivering information necessary for correct muscle morphogenesis, from the early step of myoblast differentiation to the late stage of muscle maturation. Interactions between muscle and connective tissue are also critical in the adult during muscle regeneration, as impairment of the regenerative potential after injury or in neuromuscular diseases results in the progressive replacement of the muscle mass by fibrotic tissue. We conclude that bi-directional communication between muscle and connective tissue is critical for a correct assembly of the musculoskeletal system during development as well as to maintain its homeostasis in the adult.

  18. The biomechanical effects of limb lengthening and botulinum toxin type A on rabbit tendon.

    Science.gov (United States)

    Olabisi, Ronke M; Best, Thomas M; Hurschler, Christof; Vanderby, Ray; Noonan, Kenneth J

    2010-12-01

    Numerous studies have examined the effects of distraction osteogenesis (DO) on bone, but relatively fewer have explored muscle adaptation, and even less have addressed the concomitant alterations that occur in the tendon. The purpose herein was to characterize the biomechanical properties of normal and elongated rabbit (N = 20) tendons with and without prophylactic botulinum toxin type A (BTX-A) treatment. Elastic and viscoelastic properties of Achilles and Tibialis anterior (TA) tendons were evaluated through pull to failure and stress relaxation tests. All TA tendons displayed nonlinear viscoelastic responses that were strain dependent. A power law formulation was used to model tendon viscoelastic responses and tendon elastic responses were fit with a microstructural model. Distraction-elongated tendons displayed increases in compliance and stress relaxation rates over undistracted tendons; BTX-A administration offset this result. The elastic moduli of distraction-lengthened TA tendons were diminished (p = 0.010) when distraction was combined with gastrocnemius (GA) BTX-A administration, elastic moduli were further decreased (p = 0.004) and distraction following TA BTX-A administration resulted in TA tendons with moduli not different from contralateral control (p > 0.05). Compared to contralateral control, distraction and GA BTX-A administration displayed shortened toe regions, (p = 0.031 and 0.038, respectively), while tendons receiving BTX-A in the TA had no differences in the toe region (p > 0.05). Ultimate tensile stress was unaltered by DO, but stress at the transition from the toe to the linear region of the stress-stretch curve was diminished in all distraction-elongated TA tendons (p properties. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. A comprehensive strength testing protocol offers no clinical value in predicting risk of hamstring injury: a prospective cohort study of 413 professional football players.

    Science.gov (United States)

    van Dyk, Nicol; Bahr, Roald; Burnett, Angus F; Whiteley, Rod; Bakken, Arnhild; Mosler, Andrea; Farooq, Abdulaziz; Witvrouw, Erik

    2017-12-01

    Hamstring injuries remain prevalent across a number of professional sports. In football, the incidence has even increased by 4% per year at the Champions League level over the last decade. The role of muscle strength or strength ratios and their association with risk of hamstring injury remain restricted by small sample sizes and inconclusive results. The purpose of this study is to identify risk factors for hamstring injury in professional football players in an adequately powered, prospective cohort study. Using both established (isokinetic) and novel (eccentric hamstring test device) measures of muscle strength, we aimed to investigate the relationship between these strength characteristics over the entire range of motion with risk of hamstring injury. All teams (n=18) eligible to compete in the premier football league in Qatar underwent a comprehensive strength assessment during their annual periodic health evaluation at Aspetar Orthopaedic and Sports Medicine Hospital in Doha, Qatar. Variables included isokinetic strength, Nordic hamstring exercise strength and dynamic hamstring: quadriceps ratios. Of the 413 players included (68.2% of all league players), 66 suffered a hamstring injury over the two seasons. Only isokinetic quadriceps concentric at 300°/s (adjusted for bodyweight) was associated with risk of hamstring injury when considered categorically. Age, body mass and playing position were also associated with risk of hamstring injury. None of the other 23 strength variables examined were found to be associated with hamstring injury. The clinical value of isolated strength testing is limited, and its use in musculoskeletal screening to predict future hamstring injury is unfounded. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Extracorporeal shockwave enhanced regeneration of fibrocartilage in a delayed tendon-bone insertion repair model.

    Science.gov (United States)

    Chow, Dick Ho Kiu; Suen, Pui Kit; Huang, Le; Cheung, Wing-Hoi; Leung, Kwok-Sui; Ng, Chun; Shi, San Qiang; Wong, Margaret Wan Nar; Qin, Ling

    2014-04-01

    Fibrous tissue is often formed in delayed healing of tendon bone insertion (TBI) instead of fibrocartilage. Extracorporeal shockwave (ESW) provides mechanical cues and upregulates expression of fibrocartilage-related makers and cytokines. We hypothesized that ESW would accelerate fibrocartilage regeneration at the healing interface in a delayed TBI healing model. Partial patellectomy with shielding at the TBI interface was performed on 32 female New Zealand White Rabbits for establishing this delayed TBI healing model. The rabbits were separated into the control and ESW group for evaluations at postoperative week 8 and 12. Shielding was removed at week 4 and a single ESW treatment was applied at week 6. Fibrocartilage regeneration was evaluated histomorphologically and immunohistochemically. Vickers hardness of the TBI matrix was measured by micro-indentation. ESW group showed higher fibrocartilage area, thickness, and proteoglycan deposition than the control in week 8 and 12. ESW increased expression of SOX9 and collagen II significantly in week 8 and 12, respectively. ESW group showed a gradual transition of hardness from bone to fibrocartilage to tendon, and had a higher Vickers hardness than the control group at week 12. In conclusion, ESW enhanced fibrocartilage regeneration at the healing interface in a delayed TBI healing model. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.