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Sample records for patellar prosthesis dislocation

  1. Atraumatic patellar prosthesis dislocation with patellar tendon injury following a total knee arthroplasty: a case report

    Directory of Open Access Journals (Sweden)

    Singh Alka

    2010-01-01

    Full Text Available Abstract Introduction Total knee arthroplasty is a well-established procedure with gratifying results. There is no consensus in the literature whether to routinely resurface the patella while performing total knee arthroplasty or not. Although an extremely rare occurrence in clinical practice, patellar prosthesis dislocation is a possible complication resulting from total knee arthroplasty. Case presentation We report a rare case of atraumatic spontaneous dislocation of patellar prosthesis in a 63-year-old Caucasian man of British origin with patellar tendon injury. The patient was treated successfully through a revision of the patellar component and tendon repair. In two years follow-up the patient is asymptomatic with no sign of loosening of his patellar prosthesis. Conclusions A thorough understanding of knee biomechanics is imperative in performing total knee arthroplasty in order to achieve a better functional outcome and to prevent early prosthetic failure.

  2. Primary traumatic patellar dislocation

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    Tsai Chun-Hao

    2012-06-01

    Full Text Available Abstract Acute traumatic patellar dislocation is a common injury in the active and young adult populations. MRI of the knee is recommended in all patients who present with acute patellar dislocation. Numerous operative and non-operative methods have been described to treat the injuries; however, the ideal management of the acute traumatic patellar dislocation in young adults is still in debate. This article is intended to review the studies to the subjects of epidemiology, initial examination and management.

  3. Neglected locked vertical patellar dislocation

    Science.gov (United States)

    Gupta, Rakesh Kumar; Gupta, Vinay; Sangwan, Sukhbir Singh; Kamboj, Pradeep

    2012-01-01

    Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge. PMID:23162154

  4. Neglected locked vertical patellar dislocation

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Gupta

    2012-01-01

    Full Text Available Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge.

  5. MRI of traumatic patellar dislocation in children

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    Zaidi, A.; Cole, W. [Hospital for Sick Children, Toronto (Canada). Diagnostic Imaging; Babyn, P. [Mater Children' s, Brisbane (Australia). Paediatric Orthopaedic Surgery; Astori, I. [Univ. of Toronto (Canada). Diagnostic Imaging; White, L. [Hospital for Sick Children, Toronto (Canada). Orthopaedic Surgery; Doria, A.

    2006-11-15

    Traumatic patellar dislocations (TPD) are common injuries in children, and MRI is useful in evaluation of pediatric musculoskeletal injuries. However, no pediatric studies on the MR features of TPD have been reported. To review the injuries after TPD in children. Patients with clinical or radiological recognition of TPD and those with suggestive MR findings were selected. Bone, cartilage and soft-tissue injuries and patellofemoral relationships were assessed. Results A total of 26 patients (age range 10-18 years) were identified. The following injuries were seen: bone bruising of the inferomedial patella (81% of patients) and the lateral femoral condyle (81% of patients), cartilage injuries of the inferomedial patella (38% of patients) and the lateral femoral condyle (38% of patients), osteochondral fragments (42% of patients) and injuries of the medial patellar restraints (81% of patients). Pediatric manifestations of TPD seen on MRI are similar to those in adults. TPD is often occult in children. Early recognition of bone bruising of the patella and lateral femoral condyle, associated osteochondral injuries, and medial patellar stabilizer injury is important for timely diagnosis.

  6. MRI of traumatic patellar dislocation in children

    International Nuclear Information System (INIS)

    Zaidi, A.; Cole, W.; Babyn, P.; Astori, I.; White, L.; Doria, A.

    2006-01-01

    Traumatic patellar dislocations (TPD) are common injuries in children, and MRI is useful in evaluation of pediatric musculoskeletal injuries. However, no pediatric studies on the MR features of TPD have been reported. To review the injuries after TPD in children. Patients with clinical or radiological recognition of TPD and those with suggestive MR findings were selected. Bone, cartilage and soft-tissue injuries and patellofemoral relationships were assessed. Results A total of 26 patients (age range 10-18 years) were identified. The following injuries were seen: bone bruising of the inferomedial patella (81% of patients) and the lateral femoral condyle (81% of patients), cartilage injuries of the inferomedial patella (38% of patients) and the lateral femoral condyle (38% of patients), osteochondral fragments (42% of patients) and injuries of the medial patellar restraints (81% of patients). Pediatric manifestations of TPD seen on MRI are similar to those in adults. TPD is often occult in children. Early recognition of bone bruising of the patella and lateral femoral condyle, associated osteochondral injuries, and medial patellar stabilizer injury is important for timely diagnosis

  7. Medial patellar ossification after patellar instability: a radiographic finding indicative of prior patella subluxation/dislocation

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    Jerabek, Seth A. [Harvard Combined Orthopaedic Surgery Residency Program, Boston, MA (United States); Asnis, Peter D.; Poon, Steven K.; Gill, Thomas J. [Massachusetts General Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Bredella, Miriam A.; Ouellette, Hugue A. [Massachusetts General Hospital, Department of Radiology, Boston, MA (United States)

    2009-08-15

    To describe the correlation between medial patellar ossification and prior patella subluxation and/or dislocation. A retrospective billing database search identified 544 patients who had been diagnosed with patellar instability over a 13-year period. One hundred twenty-eight patients met the inclusion criteria. After review by a staff orthopedic surgeon and two musculoskeletal radiologists, 28 patients were found to have medial patellar ossification. The size and location of medial patellar ossification was recorded. Of the 28 patients (20 males, eight females, age 13-66 years, mean 28 years) who were found to have medial patellar ossification, 22 had radiographs, 16 had magnetic resonance imaging, and ten had both. The medial patellar ossification ranged in size from 2 to 18 mm with an average of 6.8 mm. Twelve were located in the medial patellofemoral ligament (MPFL), 14 in the medial joint capsule, and two in both the MPFL and joint capsule. Twenty-seven of 28 patients had a single ossification, and one patient had two ossifications. The timing from injury to first imaging of the lesion ranged from 10 days to a chronic history ({>=}35 years) of patellar instability. Medial patellar ossification correlates with a history of prior patella subluxation and/or dislocation. The medial ossification can be seen within the MPFL or the medial joint capsule, suggesting remote injury to these structures. The presence of this lesion will prompt physicians to evaluate for patellar instability. (orig.)

  8. Medial patellar ossification after patellar instability: a radiographic finding indicative of prior patella subluxation/dislocation

    International Nuclear Information System (INIS)

    Jerabek, Seth A.; Asnis, Peter D.; Poon, Steven K.; Gill, Thomas J.; Bredella, Miriam A.; Ouellette, Hugue A.

    2009-01-01

    To describe the correlation between medial patellar ossification and prior patella subluxation and/or dislocation. A retrospective billing database search identified 544 patients who had been diagnosed with patellar instability over a 13-year period. One hundred twenty-eight patients met the inclusion criteria. After review by a staff orthopedic surgeon and two musculoskeletal radiologists, 28 patients were found to have medial patellar ossification. The size and location of medial patellar ossification was recorded. Of the 28 patients (20 males, eight females, age 13-66 years, mean 28 years) who were found to have medial patellar ossification, 22 had radiographs, 16 had magnetic resonance imaging, and ten had both. The medial patellar ossification ranged in size from 2 to 18 mm with an average of 6.8 mm. Twelve were located in the medial patellofemoral ligament (MPFL), 14 in the medial joint capsule, and two in both the MPFL and joint capsule. Twenty-seven of 28 patients had a single ossification, and one patient had two ossifications. The timing from injury to first imaging of the lesion ranged from 10 days to a chronic history (≥35 years) of patellar instability. Medial patellar ossification correlates with a history of prior patella subluxation and/or dislocation. The medial ossification can be seen within the MPFL or the medial joint capsule, suggesting remote injury to these structures. The presence of this lesion will prompt physicians to evaluate for patellar instability. (orig.)

  9. 21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made of...

  10. Trochleoplasty and medial patellofemoral ligament reconstruction for recurrent patellar dislocation

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    K Raghuveer Reddy

    2012-01-01

    Full Text Available We report a case of recurrent patellar dislocation with high-grade trochlear dysplasia which persisted despite two previous operations. We did a Dejour′s sulcus deepening trochleoplasty, medial patellofemoral ligament reconstruction, and lateral retinacular release. Trochleoplasty and medial patellofemoral ligament reconstruction is required in patients with high grade trochlear dysplasia.

  11. High incidence of acute and recurrent patellar dislocations

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    Gravesen, Kasper Skriver; Kallemose, Thomas; Blønd, Lars

    2017-01-01

    PURPOSE: The purpose of this study was to investigate the Danish population as a whole from 1994 to 2013 to find the incidence of acute and recurrent patellar dislocation. METHODS: The study was performed as a descriptive epidemiological study. The Danish National Patient Registry was retrospecti...

  12. Femoral neuropathy due to patellar dislocation in a theatrical and jazz dancer: a case report.

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    Shin, Chris S; Davis, Brian A

    2005-06-01

    This case report describes a teenage female, high-level modern dancer who suffered multiple left patellar dislocations. Her history is atypical in that after her fifth dislocation, her recovery was hindered secondary to persistent weakness and atrophy of her quadriceps out of proportion to disuse alone. Electrodiagnostic studies and magnetic resonance imaging showed evidence of a subacute femoral neuropathy correlating chronologically with her most recent patellar dislocation. This case suggests that further diagnostic study may be warranted in patients with persistent quadriceps weakness or atrophy after a patellar dislocation, because this may suggest the presence of a femoral neuropathy. This is important because the strength training goals and precautions differ in disuse atrophy and a neuropathy. We believe this is the first reported case of a femoral neuropathy associated with the mechanism of a patellar dislocation.

  13. Total knee arthroplasty in a pseudoachondroplastic dwarfism patient with bilateral patellar dislocation.

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    Oh, Kwang-Jun; Yoon, Jung-Ro; Yang, Jae-Hyuk

    2013-01-01

    Late presentation of congenital patellar dislocation with advanced osteoarthritis is rare. This article presents a case of a 59-year-old man with underlying pseudoachondroplastic dwarfism. Advanced osteoarthritis due to bilateral neglected congenital patellar dislocation was treated with total knee arthroplasty without patella relocation surgery. Two years later, the patient had an improvement in Knee Society scores, painless function, and stability. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Primary patellar dislocations without surgical stabilization or recurrence: how well are these patients really doing?

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    Magnussen, Robert A; Verlage, Megan; Stock, Elizabeth; Zurek, Lauren; Flanigan, David C; Tompkins, Marc; Agel, Julie; Arendt, Elizabeth A

    2017-08-01

    While a significant research has gone into identifying patients at highest risk of recurrence following primary patellar dislocation, there has been little work exploring the outcomes of patients who do not have a recurrent patellar dislocation. We hypothesize that patients without recurrent dislocation episodes will exhibit significantly higher KOOSs than those who suffer recurrent dislocations, but lower scores than published age-matched normative data. A retrospective review of patients with nonoperatively treated primary lateral patellar dislocations was carried out, and patients were contacted at a mean of 3.4 years (range 1.3-5.5 years) post-injury. Information regarding subsequent treatment and recurrent dislocations along with patient-reported outcome scores and activity level was collected. One hundred and eleven patients (29.8 %) of 373 eligible patients agreed to study participation, seven of whom were excluded because they underwent subsequent patellar stabilization surgery on the index knee. Seventy-six patients (73.1 %) reported no further dislocation events, and the mean KOOS subscales at follow-up were: symptoms-80.2 ± 18.8, pain-81.8 ± 16.2, ADL-88.7 ± 15.9, sport/recreation-72.1 ± 24.4, and QOL-63.9 ± 23.8 at a mean follow-up of 3.3 years (range 1.3-5.5 years). No significant differences in any of the KOOS subscales were noted between these patients and the group that reported recurrent patellar dislocations. Only 26.4 % of the patients without further dislocations reported they were able to return to desired sport activities without limitations following their dislocation. Patients who do not report recurrent patellar dislocations following nonoperative treatment of primary patellar dislocations are in many cases limited by this injury 3 years following the initial dislocation event. Retrospective cohort study, Level III.

  15. MRI after patellar dislocation. Assessment of risk factors and injury to the joint

    International Nuclear Information System (INIS)

    Diederichs, G.

    2013-01-01

    Patellar dislocation is the lateral displacement of the patella from the femoral trochlea. Affected individuals typically have underlying anatomic risk factors of variable magnitude, which, in conjunction with leg rotation, cause the event. Magnetic resonance imaging (MRI) permits straightforward diagnosis of the typical features of recent patellar dislocation: contusion edema of the inferomedial patella and the lateral femoral condyle as well as rupture of the medial patellofemoral ligament. In case of concomitant osteochondral injury, early surgical refixation may be indicated, depending on the size. After a first dislocation, which can damage the capsuloligamentous stabilizers, subjects may sustain further dislocations or even develop chronic patellofemoral instability, depending on the presence and severity of anatomic variants. A wide range of conservative and surgical treatments are available. While a first patellar dislocation is often treated conservatively, surgical strategies after a second dislocation depend on the pattern of injury and the severity of underlying anatomic risk factors. The most relevant predisposing variants are trochlear dysplasia, patella alta, and an abnormal tibial tubercle to trochlear groove distance (TT-TG). The radiologist's report should give a quantitative estimate of both the injuries resulting from dislocation and the underlying anatomic risk factors. An accurate characterization of the individual pathomechanism is crucial for tailoring treatment. (orig.)

  16. High-resolution MRI using a microscopy coil for the diagnosis of recurrent lateral patellar dislocation

    International Nuclear Information System (INIS)

    Iwata, Yuki; Fujii, Masahiko; Muratsu, Hirotsugu; Kurosaka, Masahiro; Kawamitsu, Hideaki; Sugimura, Kazuro; Shibanuma, Hitoshi

    2006-01-01

    Magnetic resonance imaging (MRI) has been commonly used for the preoperative evaluation of recurrent lateral patellar dislocation (RLPD). The purpose of this study was to determine the usefulness of high-resolution MRI (HR-MRI) with a microscopy coil for diagnosing RLPD. The study group consisted of 15 patients with clinically diagnosed RLPD and 10 normal volunteers. All studies were performed on a 1.5-T MR system. First, conventional MRIs of the whole knee joint were obtained using the knee coil. Then HR-MRI scans using a microscopy coil in the medial aspect of the patella were obtained at the level of the superior pole of the patella, targeting the medial patellofemoral ligament (MPFL). The acquired HR-MRIs with RLPD were reviewed concerning the MPFL injury and the patellar injury. The MPFL was distinguished as a separate ligament, and the layer structure of the patellar cartilage was visualized clearly in all volunteers. The MPFL injury was visualized in 12 cases (87%); it included discontinuity, thickening, and loosening. The patellar injury was visualized in 11 cases (73%), which included dissecans of the medial margin and cartilage injuries. HR-MRI with a microscopy coil provides precise information of the MPFL and patellar cartilage injury for the diagnosis of RLPD. (author)

  17. [Tripolar arthroplasty for recurrent total hip prosthesis dislocation].

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    Beaulé, P-E; Roussignol, X; Schmalzried, T-P; Udomkiat, P; Amstutz, H-C; Dujardin, F-H

    2003-05-01

    The purpose of this study was to assess the results of revision surgery for recurrent total hip prosthesis dislocation using a tripolar prosthesis composed of a conventional stem with a mobile head of an intermediary prosthesis measuring more than 40 mm and a modified cup. This technique was used in two centers in Rouen France and Los Angeles USA. Twenty-one hips in 21 patients were operated on. The mobile heads measured 40 to 47 mm. Mean patient age was 70 years (range 29-92). The indication for the tripolar prosthesis was reserved for extremely unstable hips in patients with major risk factors for recurrent dislocation. These 21 patients had experienced 95 dislocations. The acetabular cup was custom-made for the large-diameter heads. A cemented polyethylene cup was used in 14 cases and a press-fit metal-backed around a polyethylene insert in 7. The polyethylene thickness varied from 6.5 to 16 mm for the cemented cups and 4 to 5 mm for the press-fit cups. Fourteen femoral stems were left in place as were two press-fit cups where only the inserts were changed. Mean follow-up was 5.4 years (range 3-11.8). There has been no recurrent dislocation for 20 hips. One patient experienced a dislocation one week after surgery which required a second revision procedure to reposition the acetabular implant. Final outcome was good at 7.6 years for this hip. One patient who had not had any recurrent dislocation died 4 years after the revision surgery due to a cause unrelated to the prosthesis. Two patients were lost to follow-up at 3.7 and 6 years, both were pain free and had no radiological anomalies. Infection occurred in one patient undergoing chemotherapy for a myeloma; the head and neck had to be resected. For the 20 other patients, functional outcome, assessed with the UCLA score, showed improvement in pain (5.8 preoperatively, 9.2 at last follow-up), walking (4.8 and 8 respectively), function (4 and 6 respectively), and daily activities (3.3 and 5.2 respectively). A

  18. Vertical Patellar Dislocation: Reduction by the Push Up and Rotate Method, A Case Report and Literature Review.

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    Ahmad Khan, Hayat; Bashir Shah, Adil; Kamal, Younis

    2016-11-01

    Patellar dislocation is an emergency. Vertical patellar dislocation is rare, often seen in adolescents and mostly due to sports injuries or high-velocity trauma. Few cases have been reported in the literature. Closed or open reduction under general anesthesia is often needed. We report a case of vertical locked patellar dislocation in a 26-year-old male, which was reduced by a simple closed method under spinal anaesthesia. A literature review regarding the various methods of treatment is also discussed. A 26-year-old male experienced a trivial accident while descending stairs, sustaining patellar dislocation. The closed method of reduction was attempted, using a simple technique. Reduction was confirmed and postoperative rehabilitation was started. Follow-up was uneventful. Vertical patellar dislocations are encountered rarely in the emergency department. Adolescents are not the only victims, and high-velocity trauma is not the essential cause. Unnecessary manipulation should be avoided. The closed reduction method is simple, but the surgeon should be prepared for open reduction.

  19. Trochleoplasty as a Solitary Treatment for Recurrent Patellar Dislocation Results in Good Clinical Outcome in Adolescents.

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    Camathias, Carlo; Studer, Katrin; Kiapour, Ata; Rutz, Erich; Vavken, Patrick

    2016-11-01

    The essential static patellar stabilizer is a normal-shaped trochlear groove. A dysplastic groove destabilizes the patella. Trochleoplasty approaches this underlying condition and reshapes the trochlea. However, studies have reported on trochleoplasty for revision cases or as accompanied by other interventions. The effect of trochleoplasty alone remains unexplained. To introduce trochleoplasty as a stand-alone treatment for recurrent patellar dislocation and to compare its pre- to postoperative functional and clinical variables. Case series; Level of evidence, 4. A trochleoplasty was performed in 50 knees (27 right) in 44 patients (30 females; mean ± SD age, 15.6 ± 2.0 years). The indication for surgery was recurrent patellar dislocation not responding to nonoperative treatment (>6 months), with types B through D dysplasia and closed or closing physes in adolescents aged 10 to 20 years. Assessment included J-sign and apprehension test, Kujala and Lysholm scores, patients' subjective assessment and activity level according to the International Knee Documentation Committee questionnaire, and patients' overall satisfaction. The Caton-Deschamps ratio and the lateral condyle index were measured. Pre- versus postoperative values were compared with a paired Wilcoxon signed-rank test. The minimum follow-up was 24 months (33 ± 10.6 months). The Kujala score improved from 71 preoperatively to 92 postoperatively (P debridement. In this study, trochleoplasty as a solitary treatment for recurrent patellofemoral dislocations in patients with trochlear dysplasia resulted in good clinical outcomes if severe torsional and axial malalignment was excluded. Kujala and Lysholm scores increased postoperatively, as well as subjective International Knee Documentation Committee assessment of outcomes, activity level, and overall satisfaction. © 2016 The Author(s).

  20. Simultaneous MPFL and LPFL reconstruction for recurrent lateral patellar dislocation with medial patellofemoral instability

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    Masashi Kusano

    2014-01-01

    Full Text Available We report an extremely rare case of both recurrent lateral patella dislocation and medial patellofemoral instability, following prior operations to correct patella maltracking. Manual translation of the patella revealed medial and lateral instability with a positive apprehension sign. 3-D computer modelling of kinematics based on MRI data demonstrated that the patella deviated laterally at full extension and translated medially with knee flexion. The medial and lateral patellofemoral ligaments were reconstructed simultaneously with hamstring tendons, alleviating peripatellar pain and patellar instability in both directions.

  1. Bone bruise in acute traumatic patellar dislocation: volumetric magnetic resonance imaging analysis with follow-up mean of 12 months

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    Paakkala, Antti; Paakkala, Timo [Tampere University Hospital, Department of Radiology, Tampere (Finland); Sillanpaeae, Petri; Maeenpaeae, Heikki [Tampere University Hospital, Department of Orthopaedics and Traumatology, Tampere (Finland); Huhtala, Heini [University of Tampere, School of Public Health, Tampere (Finland)

    2010-07-15

    The aim of the study was to assess volumetric analysis of bone bruises in acute primary traumatic patellar dislocation by magnetic resonance imaging (MRI) and resolving resolution of bruises in follow-up MRI. MRI was performed in 23 cases. A follow-up examination was done at a mean of 12 months after dislocation. Volumes of patellar and femur bruises for every patient were evaluated separately by two musculoskeletal radiologists, and mean values of the bruises were assessed. Other MRI findings were evaluated, together with agreement by consensus. Bone bruise volumes were compared with other MR findings. In the acute study 100% of patients showed bruising of the lateral femoral condyle and 96% bruising of the patella. The bruise was located at the medial femoral condyle in 30% and at the patellar median ridge in 74% of patients. The median volume of the femoral bruise was 25,831 mm{sup 3} and of the patellar bruise 2,832 mm{sup 3}. At the follow-up study 22% of patients showed bruising of the lateral femoral condyle and 39% bruising of the patella, the median volumes of the bruises being 5,062 mm{sup 3} and 1,380 mm{sup 3}, respectively. Larger patellar bruise volume correlated with larger femur bruise volume in the acute (r=0.389, P=0.074) and the follow-up (r=1.000, P<0.01) studies. Other MRI findings did not correlate significantly with bone bruise volumes. Bone bruising is the commonest finding in cases of acute patellar dislocation, being seen even 1 year after trauma and indicating significant bone trabecular injury in the patellofemoral joint. A large bruise volume may be associated with subsequent chondral lesion progression at the patella. We concluded that the measurement of bone bruise volume in patients with acute patellar dislocation is a reproducible method but requires further studies to evaluate its clinical use. (orig.)

  2. Bone bruise in acute traumatic patellar dislocation: volumetric magnetic resonance imaging analysis with follow-up mean of 12 months

    International Nuclear Information System (INIS)

    Paakkala, Antti; Paakkala, Timo; Sillanpaeae, Petri; Maeenpaeae, Heikki; Huhtala, Heini

    2010-01-01

    The aim of the study was to assess volumetric analysis of bone bruises in acute primary traumatic patellar dislocation by magnetic resonance imaging (MRI) and resolving resolution of bruises in follow-up MRI. MRI was performed in 23 cases. A follow-up examination was done at a mean of 12 months after dislocation. Volumes of patellar and femur bruises for every patient were evaluated separately by two musculoskeletal radiologists, and mean values of the bruises were assessed. Other MRI findings were evaluated, together with agreement by consensus. Bone bruise volumes were compared with other MR findings. In the acute study 100% of patients showed bruising of the lateral femoral condyle and 96% bruising of the patella. The bruise was located at the medial femoral condyle in 30% and at the patellar median ridge in 74% of patients. The median volume of the femoral bruise was 25,831 mm 3 and of the patellar bruise 2,832 mm 3 . At the follow-up study 22% of patients showed bruising of the lateral femoral condyle and 39% bruising of the patella, the median volumes of the bruises being 5,062 mm 3 and 1,380 mm 3 , respectively. Larger patellar bruise volume correlated with larger femur bruise volume in the acute (r=0.389, P=0.074) and the follow-up (r=1.000, P<0.01) studies. Other MRI findings did not correlate significantly with bone bruise volumes. Bone bruising is the commonest finding in cases of acute patellar dislocation, being seen even 1 year after trauma and indicating significant bone trabecular injury in the patellofemoral joint. A large bruise volume may be associated with subsequent chondral lesion progression at the patella. We concluded that the measurement of bone bruise volume in patients with acute patellar dislocation is a reproducible method but requires further studies to evaluate its clinical use. (orig.)

  3. [Current status and expectations in the surgical treatment of recurrent lateral patellar dislocation].

    Science.gov (United States)

    Zhao, Zhi-Dong; Li, Peng-Cui; Wei, Xiao-Chun

    2017-11-25

    Up to now, surgical treatment of recurrent lateral patellar dislocation mainly includes: medial patellofemoral ligament reconstruction, tibial tubercle osteotomy, trochleoplasty, lateral retinacular release, derotation osteotomy and so on . Clinical reports show that: the use of a single or combined with several methods have achieved ideal short to mid-term clinical outcomes. However, there is no consolidate criterion concerning the choices of different kinds of surgical ways for the treatment of individual recurrent lateral patellar dislocation. Meanwhile, with the wide use of MPFL reconstruction and other surgical options, there are more and more complications and failures that are worthy and necessary for us to pay attention to, even though its high success rate. The aim of this article is to make a systematic review of the application status of different surgical methods, collecting the positive results we have achieved, illuminating application keys of surgical techniques, guiding patient-specific therapy more precisely. Copyright© 2017 by the China Journal of Orthopaedics and Traumatology Press.

  4. [Reconstruction of medial patellofemoral ligament with transposition of great adductor muscular tendon for the treatment of teenagers' recurrent patellar dislocation].

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    Shao, Chuan-Qiang; Chen, Chang-Chun; Zhao, Chun-Cheng; Yang, Hong-Mei; Kang, Yan-Zhong

    2017-06-25

    To investigate surgical method and clinical curative effects of medial patellofemoral ligament (MPFL) reconstruction with great adductor muscular tendon in treating teenagers' recurrent patellar dislocation. From May 2012 to September 2014, 19 patients with recurrent dislocation of patellar, including 6 males and 13 females with an average of 16 years old (ranged from 13 to 17 years), the courses of disease ranged from 3 to 18 months(averaged 6 months). All patients were underwent great adductor muscular tendon transposition to reconstruct medial patellofemoral ligament. The curative effects were evaluated by preoperative and postoperative with Lysholm scores and Patellofemoral angle and Q angle. All patients were followed up from 12 to 18 months with an average of 16.5 months. Primary healing was achieved at stage I. No pain, swelling and patellar dislocation or subluxation occurred. Patellofemoral angle increased from preoperative (-3.8±4.9)° to (10.3±4.1)° postoperatively. Q angle decreased from preoperative(16.4±3.1)° to(10.5±1.2)° postoperatively; Lysholm scores were improved from preoperative (68.6±8.5) to (93.7±6.5) final follow-up ( P teenagers' recurrent patellar dislocation.

  5. Supracondylar correction osteotomy to prevent repetitive posterior dislocation of a hip prosthesis

    NARCIS (Netherlands)

    Haverkamp, D.; Marti, R. K.

    2008-01-01

    Recurrent dislocation of a total hip prosthesis can be a challenging and often disappointing problem. This case report describes a 78-year-old woman who had recurrent posterior dislocations of a revision total hip replacement (THR) that occurred on flexion and internal rotation of the hip. The

  6. Long-Term Follow-Up of Nonoperatively and Operatively Treated Acute Primary Patellar Dislocation in Skeletally Immature Patients

    Directory of Open Access Journals (Sweden)

    Eva Bengtsson Moström

    2014-01-01

    Full Text Available Purpose. The present study reports a long-term follow-up of acute primary patellar dislocation in patients with open physes. The purpose of the study was to evaluate knee function and recurrence rates after surgical and nonsurgical treatment of patellar dislocation. Methods. A total of 51 patients, including 29 girls and 22 boys, who were 9–14 years of age at the time of injury, were retrospectively evaluated. The minimum follow-up time was 5 years. Thigh muscle torque, range of motion, the squat test, the knee injury and osteoarthritis outcome score (KOOS, the Kujala score, and the recurrence rate were registered. Radiological predisposing factors at the time of injury were determined. Results. Quality of life and sports/recreation were the most affected subscales, according to KOOS, and a reduced Kujala score was also observed in all treatment groups. The surgically treated patients had a significantly lower recurrence rate. Those patients also exhibited reduced muscle performance, with a hamstring to quadriceps ratio (H/Q of 1.03. The recurrence rate was not correlated with knee function. Conclusions. Patellar dislocation in children influences subjective knee function in the long term. Surgery appears to reduce the recurrence rate, but subjective knee function was not restored.

  7. Injury patterns of medial patellofemoral ligament after acute lateral patellar dislocation in children: Correlation analysis with anatomical variants and articular cartilage lesion of the patella

    International Nuclear Information System (INIS)

    Zhang, Guang-ying; Ding, Hong-yu; Zheng, Lei; Ji, Bing-jun; Shi, Hao; Feng, Yan

    2017-01-01

    To assess the relationship between injury patterns of medial patellofemoral ligament (MPFL) and anatomical variants and patellar cartilage lesions after acute lateral patellar dislocation (LPD) in children. MR images were obtained in 140 children with acute LPD. Images were acquired and evaluated using standardised protocols. Fifty-eight cases of partial MPFL tear and 75 cases of complete MPFL tear were identified. Injuries occurred at an isolated patellar insertion (PAT) in 52 cases, an isolated femoral attachment (FEM) in 42 cases and an isolated mid-substance (MID) in five cases. More than one site of injury was identified in 34 cases. Compared with Wiberg patellar type C, Wiberg patellar type B predisposed to complete MPFL tear (P = 0.042). No correlations were identified between injury patterns of MPFL and trochlear dysplasia, patellar height and tibial tuberosity-trochlear groove distance (P > 0.05). Compared with partial MPFL tear, complete MPFL tear predisposed to Grade-IV and Grade-V patellar chondral lesion (P = 0.02). There were no correlations between incidence of patellar cartilage lesion and injury locational-subgroups of MPFL (P = 0.543). MPFL is most easily injured at the PAT in children. Wiberg patellar type B predisposes to complete MPFL tear. Complete MPFL tear predisposes to a higher grade of patellar chondral lesion. (orig.)

  8. Injury patterns of medial patellofemoral ligament after acute lateral patellar dislocation in children: Correlation analysis with anatomical variants and articular cartilage lesion of the patella

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guang-ying; Ding, Hong-yu [Shandong Provincial Qianfoshan Hospital of Shandong University, Department of Ultrasonography, Jinan (China); Zheng, Lei; Ji, Bing-jun [Shandong Provincial Corps Hospital of Chinese People' s Armed Police Force, Department of Radiology, Jinan (China); Shi, Hao [Shandong Provincial Qianfoshan Hospital of Shandong University, Department of Radiology, Jinan (China); Feng, Yan [Affiliated Hospital of Binzhou Medical College, Department of Radiology, Binzhou (China)

    2017-03-15

    To assess the relationship between injury patterns of medial patellofemoral ligament (MPFL) and anatomical variants and patellar cartilage lesions after acute lateral patellar dislocation (LPD) in children. MR images were obtained in 140 children with acute LPD. Images were acquired and evaluated using standardised protocols. Fifty-eight cases of partial MPFL tear and 75 cases of complete MPFL tear were identified. Injuries occurred at an isolated patellar insertion (PAT) in 52 cases, an isolated femoral attachment (FEM) in 42 cases and an isolated mid-substance (MID) in five cases. More than one site of injury was identified in 34 cases. Compared with Wiberg patellar type C, Wiberg patellar type B predisposed to complete MPFL tear (P = 0.042). No correlations were identified between injury patterns of MPFL and trochlear dysplasia, patellar height and tibial tuberosity-trochlear groove distance (P > 0.05). Compared with partial MPFL tear, complete MPFL tear predisposed to Grade-IV and Grade-V patellar chondral lesion (P = 0.02). There were no correlations between incidence of patellar cartilage lesion and injury locational-subgroups of MPFL (P = 0.543). MPFL is most easily injured at the PAT in children. Wiberg patellar type B predisposes to complete MPFL tear. Complete MPFL tear predisposes to a higher grade of patellar chondral lesion. (orig.)

  9. Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

    Directory of Open Access Journals (Sweden)

    Mantu Jain

    2013-10-01

    Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

  10. Early postoperative dislocation of the anterior Maverick lumbar disc prosthesis: report of 2 cases.

    Science.gov (United States)

    Gragnaniello, Cristian; Seex, Kevin A; Eisermann, Lukas G; Claydon, Matthew H; Malham, Gregory M

    2013-08-01

    The authors report on 2 cases of anterior dislocation of the Maverick lumbar disc prosthesis, both occurring in the early postoperative period. These cases developed after experience with more than 50 uneventful cases and were therefore thought to be unrelated to the surgeon's learning curve. No similar complications have been previously reported. The anterior Maverick device has a ball-and-socket design made of cobalt-chromium-molybdenum metal plates covered with hydroxyapatite. The superior and inferior endplates have keels to resist translation forces. The patient in Case 1 was a 52-year-old man with severe L4-5 discogenic pain; and in Case 2, a 42-year-old woman with disabling L4-5 and L5-S1 discogenic back pain. Both patients were without medical comorbidities and were nonsmokers with no risk factors for osteoporosis. Both had undergone uneventful retroperitoneal approaches performed by a vascular access surgeon. Computed tomography studies on postoperative Day 2 confirmed excellent prosthesis placement. Initial recoveries were uneventful. Two weeks postoperatively, after stretching (extension or hyperextension) in bed at home, each patient suffered the sudden onset of severe abdominal pain with anterior dislocation of the Maverick prosthesis. The patients were returned to the operating room and underwent surgery performed by the same spinal and vascular surgeons. Removal of the Maverick prosthesis and anterior interbody fusion with a separate cage and plate were performed. Both patients had recovered well with good clinical and radiological recovery at the 6- and 12-month follow-ups. Possible causes of the anterior dislocation of the Maverick prosthesis include the following: 1) surgeon error: In both cases the keel cuts were neat, and early postoperative CT confirmed good placement of the prosthesis; 2) equipment problem: The keel cuts may have been too large because the cutters were worn, which led to an inadequate press fit of the implants; 3) prosthesis

  11. Imaging patellar complications after knee arthroplasty

    International Nuclear Information System (INIS)

    Melloni, Pietro; Valls, Rafael; Veintemillas, Maite

    2008-01-01

    The purpose of this study is to describe complications affecting the patella in patients with total or partial knee arthroplasty. We respectively analysed plain-film radiographs, as well as ultrasound images when acquired, in a consecutive series of 1272 patients. The mean interval from knee replacement to patellar complications was 5 years and 7 months (range, 5 months to 14 years). The complications described include fracture, instability, dislocation or luxation, necrosis of the patella, infection of the patella, erosion of the patella, patellar impingement on the prosthesis and patellar or quadricipital tendon tear. We discuss the pathological imaging findings in the patella and their differential diagnosis after knee arthroplasty. Patellar complications after knee arthroplasty are uncommon but often potentially serious

  12. Imaging patellar complications after knee arthroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Melloni, Pietro [Unitat de Imatge d' Alta Tecnologia, Centre Diagnostic, Corporacio Parc Tauli, Universitat Autonoma de Barcelona, Sabadell (Barcelona) (Spain)], E-mail: pmelloni@cspt.es; Valls, Rafael; Veintemillas, Maite [Unitat de Imatge d' Alta Tecnologia, Centre Diagnostic, Corporacio Parc Tauli, Universitat Autonoma de Barcelona, Sabadell (Barcelona) (Spain)

    2008-03-15

    The purpose of this study is to describe complications affecting the patella in patients with total or partial knee arthroplasty. We respectively analysed plain-film radiographs, as well as ultrasound images when acquired, in a consecutive series of 1272 patients. The mean interval from knee replacement to patellar complications was 5 years and 7 months (range, 5 months to 14 years). The complications described include fracture, instability, dislocation or luxation, necrosis of the patella, infection of the patella, erosion of the patella, patellar impingement on the prosthesis and patellar or quadricipital tendon tear. We discuss the pathological imaging findings in the patella and their differential diagnosis after knee arthroplasty. Patellar complications after knee arthroplasty are uncommon but often potentially serious.

  13. MRI after patellar dislocation. Assessment of risk factors and injury to the joint; MRT nach Patellaluxation. Quantifizierung der Risikofaktoren und Beschreibung der Folgeschaeden

    Energy Technology Data Exchange (ETDEWEB)

    Diederichs, G. [Charite Universitaetsmedizin, Berlin (Germany). Radiologie; Scheffler, S. [Charite Universitaetsmedizin, Berlin (Germany). Zentrum fuer Muskuloskeletale Chirurgie; Chirurgisch Orthopaedischer PraxisVerbund, Berlin (Germany)

    2013-07-15

    Patellar dislocation is the lateral displacement of the patella from the femoral trochlea. Affected individuals typically have underlying anatomic risk factors of variable magnitude, which, in conjunction with leg rotation, cause the event. Magnetic resonance imaging (MRI) permits straightforward diagnosis of the typical features of recent patellar dislocation: contusion edema of the inferomedial patella and the lateral femoral condyle as well as rupture of the medial patellofemoral ligament. In case of concomitant osteochondral injury, early surgical refixation may be indicated, depending on the size. After a first dislocation, which can damage the capsuloligamentous stabilizers, subjects may sustain further dislocations or even develop chronic patellofemoral instability, depending on the presence and severity of anatomic variants. A wide range of conservative and surgical treatments are available. While a first patellar dislocation is often treated conservatively, surgical strategies after a second dislocation depend on the pattern of injury and the severity of underlying anatomic risk factors. The most relevant predisposing variants are trochlear dysplasia, patella alta, and an abnormal tibial tubercle to trochlear groove distance (TT-TG). The radiologist's report should give a quantitative estimate of both the injuries resulting from dislocation and the underlying anatomic risk factors. An accurate characterization of the individual pathomechanism is crucial for tailoring treatment. (orig.)

  14. Ultrasound-Guided Femoral Nerve Block to Facilitate the Closed Reduction of a Dislocated Hip Prosthesis

    Directory of Open Access Journals (Sweden)

    Edward Carlin

    2017-10-01

    Full Text Available Prosthetic hip dislocation is a common but unfortunate complication in patients who have undergone total hip arthroplasty. Successful closed reduction in the emergency department leads to a reduced length of stay and rate of hospitalization. 1, 2 The use of regional anesthesia by femoral nerve block represents a novel approach for controlling pain in patients with hip pathologies. 3 Ultrasound-guided approaches have been used with great success for controlling pain in patients with hip fractures. 4, 5 Here we report the case of a 90-year-old male who presented with a dislocated hip prosthesis, which was subsequently corrected with closed reduction following delivery of regional anesthesia to the femoral nerve under ultrasound guidance. To our knowledge, this represents the first reported use of an ultrasound-guided femoral nerve block to facilitate closed reduction of a dislocated prosthetic hip, and highlights a novel approach that avoids the use of procedural sedation in an elderly patient.

  15. Does different duration of non-operative immobilization have an effect on the redislocation rate of primary patellar dislocation?

    DEFF Research Database (Denmark)

    Kaewkongnok, Bo; Bøvling, Anders; Milandt, Nikolaj

    2018-01-01

    BACKGROUND: Immobilization devices such as plaster splints, casts and braces have been used for first time patellar dislocation (FTPD) in order to prevent redislocation. This study evaluates different non-operative immobilization regimes upon rates of redislocation. METHODS: A retrospective cohort...... study with a study population of 1366 in which 601 subjects under 30years with FTPD were included from three hospitals. Exclusion criteria were osteochondral fracture, ligament injury and subluxation. Subjects were divided into five groups; unknown/none, two weeks of brace, two weeks of brace followed...... by bandage, four weeks of brace and six weeks of brace with increasing of range of motion. Radiographs were evaluated for trochlear dysplasia (TD), patella alta, trochlear depth and growth zone. Crude analysis and logistic regression adjusted for radiographic assessments, age, gender and rehabilitation...

  16. Patellar dislocations in children, adolescents and adults: A comparative MRI study of medial patellofemoral ligament injury patterns and trochlear groove anatomy

    International Nuclear Information System (INIS)

    Balcarek, Peter; Walde, Tim Alexander; Frosch, Stephan; Schuettrumpf, Jan P.; Wachowski, Martin M.; Stuermer, Klaus M.; Frosch, Karl-Heinz

    2011-01-01

    Purpose: The first aim was to compare medial patellofemoral ligament injury patterns in children and adolescents after first-time lateral patellar dislocations with the injury patterns in adults. The second aim was to evaluate the trochlear groove anatomy at different developmental stages of the growing knee joint. Materials and methods: Knee magnetic resonance (MR) images were collected from 22 patients after first-time patellar dislocations. The patients were aged 14.2 years (a range of 11-15 years). The injury pattern of the medial patellofemoral ligament was analysed, and trochlear dysplasia was evaluated with regard to sulcus angle, trochlear depth and trochlear asymmetry. The control data consisted of MR images from 21 adult patients who were treated for first-time lateral patellar dislocation. Results: After patellar dislocation, injury to the medial patellofemoral ligament was found in 90.2% of the children and in 100% of the adult patients. Injury patterns of the medial patellofemoral ligament were similar between the study group and the control group with regard to injury at the patellar attachment site (Type I), to the midsubstance (Type II) and to injury at the femoral origin (Type III) (all p > 0.05). Combined lesions (Type IV) were significantly less frequently observed in adults when compared to the study group (p = 0.02). The magnitude of trochlear dysplasia was similar in children, adolescents and adults with regard to all three of the measured parameter-values (all p > 0.05). In addition, the articular cartilage had a significant effect on the distal femur geometry in both paediatrics and adults. Conclusion: First, the data from our study indicated that the paediatric medial patellofemoral ligament injury patterns, as seen on MR images, were similar to those in adults. Second, the trochlear groove anatomy and the magnitude of trochlear dysplasia, respectively, did not differ between adults and paediatrics with patellar instability. Thus

  17. Patellar dislocations in children, adolescents and adults: A comparative MRI study of medial patellofemoral ligament injury patterns and trochlear groove anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Balcarek, Peter, E-mail: peter.balcarek@med.uni-goettingen.de [Department of Trauma Surgery, Plastic and Reconstructive Surgery, University Medicine, 37075 Goettingen (Germany); Walde, Tim Alexander; Frosch, Stephan; Schuettrumpf, Jan P.; Wachowski, Martin M.; Stuermer, Klaus M. [Department of Trauma Surgery, Plastic and Reconstructive Surgery, University Medicine, 37075 Goettingen (Germany); Frosch, Karl-Heinz [Department of Trauma and Reconstructive Surgery, Asklepios Clinic St. Georg, Hamburg (Germany)

    2011-09-15

    Purpose: The first aim was to compare medial patellofemoral ligament injury patterns in children and adolescents after first-time lateral patellar dislocations with the injury patterns in adults. The second aim was to evaluate the trochlear groove anatomy at different developmental stages of the growing knee joint. Materials and methods: Knee magnetic resonance (MR) images were collected from 22 patients after first-time patellar dislocations. The patients were aged 14.2 years (a range of 11-15 years). The injury pattern of the medial patellofemoral ligament was analysed, and trochlear dysplasia was evaluated with regard to sulcus angle, trochlear depth and trochlear asymmetry. The control data consisted of MR images from 21 adult patients who were treated for first-time lateral patellar dislocation. Results: After patellar dislocation, injury to the medial patellofemoral ligament was found in 90.2% of the children and in 100% of the adult patients. Injury patterns of the medial patellofemoral ligament were similar between the study group and the control group with regard to injury at the patellar attachment site (Type I), to the midsubstance (Type II) and to injury at the femoral origin (Type III) (all p > 0.05). Combined lesions (Type IV) were significantly less frequently observed in adults when compared to the study group (p = 0.02). The magnitude of trochlear dysplasia was similar in children, adolescents and adults with regard to all three of the measured parameter-values (all p > 0.05). In addition, the articular cartilage had a significant effect on the distal femur geometry in both paediatrics and adults. Conclusion: First, the data from our study indicated that the paediatric medial patellofemoral ligament injury patterns, as seen on MR images, were similar to those in adults. Second, the trochlear groove anatomy and the magnitude of trochlear dysplasia, respectively, did not differ between adults and paediatrics with patellar instability. Thus

  18. Evaluation of medial patellofemoral ligament tears after acute lateral patellar dislocation: comparison of high-frequency ultrasound and MR

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guang-Ying; Ding, Hong-Yu [Shandong University, Department of Ultrasonography, Qianfoshan Hospital, Jinan (China); Zheng, Lei; Sun, Bai-Sheng [Chinese People' s Armed Police Force, Department of Radiology, Shandong Provincial Corps Hospital, Jinan (China); Li, En-Miao [Jinan Third People' s Hospital, Department of Ultrasonography, Jinan (China); Shi, Hao [Shandong University, Department of Radiology, Qianfoshan Hospital, Jinan (China)

    2015-01-15

    The purpose of this study was to compare the diagnostic performance of high-frequency ultrasound with MR in the evaluation of medial patellofemoral ligament (MPFL) lesions after acute lateral patellar dislocation (LPD). High-frequency ultrasound and MR images were prospectively obtained in 97 consecutive patients with acute LPD. Images were acquired using standardised protocols and were independently evaluated by two radiologists. The MPFL was assessed at three sites (patellar insertion, femoral attachment, and mid-substance) for signs of injury. Of a total of 291 sites in 97 MPFLs, 127 showed proven MPFL tear at surgery, including 51 sites of complete tear and 76 sites of partial tear. In a site-based analysis, the sensitivity, specificity, and accuracy of high-frequency ultrasound was 90.8 %, 96.3 %, and 94.6 %, respectively, for partial MPFL tear and 86.3 %, 96.3 %, and 94 %, respectively, for complete tear. For MR, the sensitivity, specificity, and accuracy was 81.6 %, 95.7 %, and 91.3 %, respectively, for partial MPFL tear and 80.4 %, 95.7 %, and 92.1 %, respectively, for complete tear. There was no statistical difference between high-frequency ultrasound and MR in the assessment of partial (P = 0.1, 0.777, 0.155) or complete (P = 0.425, 0.777, 0.449) MPFL lesions. Interobserver agreement was very good for high-frequency ultrasound and good for MR. Data suggest that high-frequency ultrasound and MR have similar diagnostic performance in the evaluation of MPFL lesions after acute LPD. (orig.)

  19. Evaluation of medial patellofemoral ligament tears after acute lateral patellar dislocation: comparison of high-frequency ultrasound and MR

    International Nuclear Information System (INIS)

    Zhang, Guang-Ying; Ding, Hong-Yu; Zheng, Lei; Sun, Bai-Sheng; Li, En-Miao; Shi, Hao

    2015-01-01

    The purpose of this study was to compare the diagnostic performance of high-frequency ultrasound with MR in the evaluation of medial patellofemoral ligament (MPFL) lesions after acute lateral patellar dislocation (LPD). High-frequency ultrasound and MR images were prospectively obtained in 97 consecutive patients with acute LPD. Images were acquired using standardised protocols and were independently evaluated by two radiologists. The MPFL was assessed at three sites (patellar insertion, femoral attachment, and mid-substance) for signs of injury. Of a total of 291 sites in 97 MPFLs, 127 showed proven MPFL tear at surgery, including 51 sites of complete tear and 76 sites of partial tear. In a site-based analysis, the sensitivity, specificity, and accuracy of high-frequency ultrasound was 90.8 %, 96.3 %, and 94.6 %, respectively, for partial MPFL tear and 86.3 %, 96.3 %, and 94 %, respectively, for complete tear. For MR, the sensitivity, specificity, and accuracy was 81.6 %, 95.7 %, and 91.3 %, respectively, for partial MPFL tear and 80.4 %, 95.7 %, and 92.1 %, respectively, for complete tear. There was no statistical difference between high-frequency ultrasound and MR in the assessment of partial (P = 0.1, 0.777, 0.155) or complete (P = 0.425, 0.777, 0.449) MPFL lesions. Interobserver agreement was very good for high-frequency ultrasound and good for MR. Data suggest that high-frequency ultrasound and MR have similar diagnostic performance in the evaluation of MPFL lesions after acute LPD. (orig.)

  20. Short-term results of medial patellofemoral ligament reconstruction for patellar dislocation

    International Nuclear Information System (INIS)

    Sakuraba, Koji; Miura, Hiromasa; Matsuda, Shuichi; Okazaki, Ken; Iwamoto, Yukihide; Fukuoka, Shinji

    2009-01-01

    The short-term results of medial patellofemoral ligament (MPFL) reconstruction were reviewed. MPFL reconstruction surgery was performed on 13 patients (13 knees, three male, five female, mean age 24.1 years) with recurrent and habitual dislocation of the patella. After average 18.5 month follow-up, there has been no recurrence of dislocation and limitation of range of motion except for one case. The mean Kujula score was 60±20.2 preoperatively and 91±15 postoperatively. According to the Crosby and Insall grading system, six ceses were excellent, six cases were good, and one case was fair to poor. On axial radiographs, the mean congruence angle was 31.3±21.4deg preoperatively and -3.65±20.72deg postoperatively. The mean tilting angle was 32.1±7.9deg preoperatively and 21.9±8.39deg postoperatively. The mean lateral shift was 41.6±9.7% preoperatively and 24.5±9.9% postoperatively. These results demonstrate the short-term effectiveness of MPFL reconstruction. (author)

  1. Treatment of recurrent patellar dislocation via knee arthroscopy combined with C-arm fluoroscopy and reconstruction of the medial patellofemoral ligament.

    Science.gov (United States)

    Li, Li; Wang, Hongbo; He, Yun; Si, Yu; Zhou, Hongyu; Wang, Xin

    2018-06-01

    Recurrent patellar dislocations were treated via knee arthroscopy combined with C-arm fluoroscopy, and reconstruction of the medial patellofemoral ligaments. Between October 2013 and March 2017, 52 cases of recurrent patellar dislocation [27 males and 25 females; age, 16-47 years (mean, 21.90 years)] were treated. Arthroscopic exploration was performed and patellofemoral joint cartilage injuries were repaired. It was subsequently determined whether it was necessary to release the lateral patellofemoral support belt. Pre-operative measurements were used to decide whether tibial tubercle osteotomy was required. Medial patellofemoral ligaments were reconstructed using autologous semitendinosus tendons. Smith and Nephew model 3.5 line anchors were used to double-anchor the medial patellofemoral margin. On the femoral side, the medial patellofemoral ligament was fixed using 7-cm, absorbable, interfacial compression screws. All cases were followed for 1-40 months (average, 21 months). The Q angle, tibial tuberosity trochlear groove distance, Insall-Salvati index, patellofemoral angle, lateral patellofemoral angle and lateral shift were evaluated on X-Ray images using the picture archiving and communication system. Subjective International Knee Documentation Committee (IKDC) knee joint functional scores and Lysholm scores were recorded. Post-operative fear was absent, and no patellar re-dislocation or re-fracture was noted during follow-up. At the end of follow-up, the patellofemoral angle (0.22±4.23°), lateral patellofemoral angle (3.44±1.30°), and lateral shift (0.36+0.14°) differed significantly from the pre-operative values (all, Ppatellofemoral ligament was effective.

  2. Patellar subluxation syndrome

    International Nuclear Information System (INIS)

    Yagi, Tomonori; Sasaki, Tetsuto; Susuda, Koichi; Moji, Junichi

    1983-01-01

    Clinical symptoms of patellar subluxation syndrome associated with pain were investigated for 24 knees of 20 patients, and the state of patella dislocation was observed by CT-scan. The patients had high incidence of an apprehension sign, showing their fear of patellar luxation. Many of them complained of patello-femoral joint pain due to chondromalacia patellae. In order to derive patellar subluxation, the method of CT-Q-contraction was carried out at the extended position of the patellar joint. In patients with patellar subluxation syndrome, the rate of shift in the diseased side was significantly higher than that of the other side, suggesting decreased muscular strength of the musculus vastus of the diseased side. Improvement of the symptoms was seen in all except one of 12 knees operated by the combined method of Green's method with Blauth's more than 6 months before. Availability of this operation was verified by the CT-Q-contraction. (Ueda, J.)

  3. Late dislocation of rotating platform in New Jersey Low-Contact Stress knee prosthesis.

    Science.gov (United States)

    Huang, Chun-Hsiung; Ma, Hon-Ming; Liau, Jiann-Jong; Ho, Fang-Yuan; Cheng, Cheng-Kung

    2002-12-01

    Five patients with late rotational dislocation of the rotating platform bearing in the New Jersey Low-Contact Stress total knee arthroplasty are reported. The prostheses had functioned well for 8 to 12 years before failure. Preoperative radiographs showed asymmetric femorotibial joint spaces. Entrapment of the dislocated bearing in three patients and spontaneous reduction of the dislocated bearing in another two patients were seen at revision. Femorotibial ligamentous instability was found after reduction. The retrieved polyethylene bearings showed advanced wear and cold flow deformities and the thickness was reduced. The revision arthroplasty was accomplished by replacement with a thicker bearing element. Progressive femorotibial ligament laxity and reduction of the thickness of polyethylene with wearing break down the originally well-balanced soft tissue tension of the knee. The rotational degree of the rotating platform bearing is unrestricted, which may result in late dislocation. Polyethylene wear is unavoidable in knee prostheses using metal contact with polyethylene even with a mobile-bearing design. Efforts to reduce polyethylene wear are mandatory.

  4. Dislocations

    Science.gov (United States)

    ... Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español First Aid: ... bones become separated. Dislocations are caused by falls and hard impacts, such as in sports injuries, and are more common in teens than ...

  5. How reliable is MRI in diagnosing cartilaginous lesions in patients with first and recurrent lateral patellar dislocations?

    Directory of Open Access Journals (Sweden)

    Haage Patrick

    2010-07-01

    Full Text Available Abstract Background Lateral dislocation of the patella (LPD leads to cartilaginous injuries, which have been reported to be associated with retropatellar complaints and the development of patellofemoral osteoarthritis. Therefore, the purpose of this study was to determine the reliability of MRI for cartilage diagnostics after a first and recurrent LPD. Methods After an average of 4.7 days following an acute LPD, 40 patients (21 with first LPDs and 19 with recurrent LPDs underwent standardized 1.5 Tesla MRI (sagittal T1-TSE, coronal STIR-TSE, transversal fat-suppressed PD-TSE, sagittal fat-suppressed PD-TSE. MRI grading was compared to arthroscopic assessment of the cartilage. Results Sensitivities and positive predictive values for grade 3 and 4 lesions were markedly higher in the patient group with first LPDs compared to the group with recurrent LPDs. Similarly, intra- and inter-observer agreement yielded higher kappa values in patients with first LPDs compared to those with recurrent LPDs. All grade 4 lesions affecting the subchondral bone (osteochondral defects, such as a fissuring or erosion, were correctly assessed on MRI. Conclusions This study demonstrated a comparatively good diagnostic performance for MRI in the evaluation of first and recurrent LPDs, and we therefore recommend MRI for the cartilage assessment after a LPD.

  6. [Dislocated fracture of the lesser trochanter with malrotation of the stem after robot assisted implantation of a cementless hip prosthesis: a casuistic report].

    Science.gov (United States)

    Prymka, M; Hassenpflug, J

    2003-08-01

    This paper presents the case of a 63 year old female with a severe coxarthrosis. She got a robot assited implantation of a cementless hip prosthesis (Osteolock, Stryker-Howmedica, Mühlheim). As operation robot the CASPAR-System (Orto-Maquet, Rastatt) was used. Initially, the clinical progress of the patient was fine. She was nearly painfree within 14 days and showed an acceptable range of motion in the operated joint (flexion/ extension 90 degrees /05 degrees /00 degrees ). She was mobilized with crutches and 15 kg weight bearing at the operated leg. 3 weeks postoperative the patient complaint about increasing pain without trauma or intensification of the weight bearing. X-rays showed not only a dislocated fracture of the lesser trochanter, but also a sinking combined with a malrotation of the stem. A revision operation was necessary,where we implanted a cemented stem. Now clinical progress was completely satisfying.

  7. Patellar Tendinopathy

    OpenAIRE

    Schwartz, Aaron; Watson, Jonathan N.; Hutchinson, Mark R.

    2015-01-01

    Context: Patellar tendinopathy is a common condition. There are a wide variety of treatment options available, the majority of which are nonoperative. No consensus exists on the optimal method of treatment. Evidence Acquisition: PubMed spanning 1962-2014. Study Design: Clinical review. Level of Evidence: Level 4. Results: The majority of cases resolve with nonoperative therapy: rest, physical therapy with eccentric exercises, cryotherapy, anti-inflammatories, corticosteroid injections, extrac...

  8. Patellar Tendinopathy.

    Science.gov (United States)

    Schwartz, Aaron; Watson, Jonathan N; Hutchinson, Mark R

    2015-01-01

    Patellar tendinopathy is a common condition. There are a wide variety of treatment options available, the majority of which are nonoperative. No consensus exists on the optimal method of treatment. PubMed spanning 1962-2014. Clinical review. Level 4. The majority of cases resolve with nonoperative therapy: rest, physical therapy with eccentric exercises, cryotherapy, anti-inflammatories, corticosteroid injections, extracorporeal shockwave therapy, glyceryl trinitrate, platelet-rich plasma injections, and ultrasound-guided sclerosis. Refractory cases may require either open or arthroscopic debridement of the patellar tendon. Corticosteroid injections provide short-term pain relief but increase risk of tendon rupture. Anti-inflammatories and injectable agents have shown mixed results. Surgical treatment is effective in many refractory cases unresponsive to nonoperative modalities. Physical therapy with an eccentric exercise program is the mainstay of treatment for patellar tendinopathy. Platelet-rich plasma has demonstrated mixed results; evidence-based recommendations on its efficacy cannot be made. In the event that nonoperative treatment fails, surgical intervention has produced good to excellent outcomes in the majority of patients. © 2015 The Author(s).

  9. [Patellar instability : diagnosis and treatment].

    Science.gov (United States)

    Ngo, Trieu Hoai Nam; Martin, Robin

    2017-12-13

    The aim of this paper is to present recent advances in surgical management of patellar instability. Several anatomical factors were reported to promote instability. We propose to classify them in two groups. Extra articular factors are valgus and torsion deformity. Articular factors include trochlea and patella dysplasia, tibial tubercle lateralization and medial patellofemoral ligament (MPFL) insufficiency. Acute patellar dislocations are treated conservatively, with exception for osteochondral and MPFL avulsion fractures that require acute reinsertion. Surgery is considered for recurrent instability. As we aim for a correction of all contributing elements, we prefer a two stages approach. Extra articular factors are treated first by osteotomy, followed by articular factors after 4-6 months. This allows separate rehabilitation protocols.

  10. The Use of Percutaneous Lumbar Fixation Screws for Bilateral Pedicle Fractures with an Associated Dislocation of a Lumbar Disc Prosthesis

    Directory of Open Access Journals (Sweden)

    William D. Harrison

    2013-01-01

    Full Text Available Study Design. Case report. Objective. To identify a safe technique for salvage surgery following complications of total disc replacement. Summary of Background Data. Lumbar total disc replacement (TDR is considered by some as the gold standard for discogenic back pain. Revision techniques for TDR and their complications are in their infancy. This case describes a successful method of fixation for this complex presentation. Methods and Results. A 48-year-old male with lumbar degenerative disc disease and no comorbidities. Approximately two weeks postoperatively for a TDR, the patient represented with acute severe back pain and the TDR polyethylene inlay was identified as dislocated anteriorly. Subsequent revision surgery failed immediately as the polyethylene inlay redislocated intraoperatively. Further radiology identified bilateral pedicle fractures, previously unseen on the plain films. The salvage fusion of L5/S1 reutilized the anterior approach with an interbody fusion cage and bone graft. The patient was then turned intraoperatively and redraped. The percutaneous pedicle screws were used to fix L5 to the sacral body via the paracoccygeal corridor. Conclusion. The robust locking screw in the percutaneous screw allowed a complete fixation of the pedicle fractures. At 3-year followup, the patient has an excellent result and has returned to playing golf.

  11. Fracture of an uncemented tantalum patellar component

    Directory of Open Access Journals (Sweden)

    Nathan L. Grimm, MD

    2016-06-01

    Full Text Available A 62-year-old man presented with the acute, atraumatic onset of pain 3 years after uncemented right total knee arthroplasty. He complained of new mechanical locking with the knee held in extension on examination and unable to flex the knee. On the plain radiographs, the patellar component peg was fractured and the plate was dislocated. The knee was immobilized, and revision to a cemented 3-peg component was performed. Fracture of a single-peg, tantalum-backed uncemented patellar component has not been described. Clinical suspicion for this should be given in the setting of acute locking. We recommend revision with a cemented polyethylene component.

  12. [Significance of lateral release in the therapy of patellar chondromalacia].

    Science.gov (United States)

    Krüger, T; Göbel, F; Huschenbett, A; Hein, W

    2002-10-01

    A retrospective study was performed in 26 patients who underwent an operation for femoro-patellar pain due to a patellar chondromalacia with or without minor patellar dislocation/lateral pressure syndrome. The average age of the patients was 28.5 (15-39) years. 22 of the 26 patients revealed minor chondral damages of the stages 1 and 2 according to Outerbridge. In 12 patients ("lavage" group), an arthroscopic joint debridement only was carried out, while an additional open, lateral retinaculum release was made in 14 patients ("lateral release" group). The patella's distance of dislocation according to Hepp was reduced on an average of 3.0 (0-7) mm (p = 0.0019). The results of Bentley's score obtained during the follow-up interval on an average of 30.1 (9 to 60) months were almost identical for both groups. "Good" and "very good" results were achieved in the "lavage" group (83.3 %) and "lateral release" group (78.6 % of the patients). Lateral release should be used in cases of patellar decentration between 5 and 10 mm and adequate pain symptoms. The post-operative distance of dislocation should be less than 5 mm. Under such conditions and with minor chondral damage, a combined approach by using an arthroscopic joint debridement and open lateral release is promising to treat a patellar dislocation/lateral pressure syndrome.

  13. Imaging assessment of patellar instability and its treatment in children and adolescents

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, Arthur B.; Sharafinski, Mark [Children' s Hospital of Wisconsin, Medical College of Wisconsin, Department of Radiology, P.O. Box 1997, Milwaukee, WI (United States); Laor, Tal; Zbojniewicz, Andrew M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2016-05-15

    Transient patellar dislocation is a common entity in children and adolescents, characterized by lateral dislocation of the patella, usually with spontaneous reduction. Many predisposing conditions have been described, including trochlear dysplasia, excessive lateral patellar tilt, patella alta and lateralization of the tibial tuberosity. Associated injuries are bone bruises of the patella and lateral femoral condyle, tears of the medial retinaculum that include the medial patellofemoral ligament (MPFL), tears of the vastus medialis obliquus muscle, injuries of articular cartilage, and intra-articular bodies. Children who are refractory to conservative management, have a large cartilage defect, or are at substantial risk for recurrent dislocations are candidates for surgical procedures to prevent future dislocations. Procedures can include MPFL repair or reconstruction, tibial tubercle repositioning and lateral retinacular release. The purpose of this review is to illustrate the imaging findings of transient patellar dislocation in the acute setting, the normal imaging appearance after surgical intervention, and post-surgical complications. (orig.)

  14. Imaging assessment of patellar instability and its treatment in children and adolescents

    International Nuclear Information System (INIS)

    Meyers, Arthur B.; Sharafinski, Mark; Laor, Tal; Zbojniewicz, Andrew M.

    2016-01-01

    Transient patellar dislocation is a common entity in children and adolescents, characterized by lateral dislocation of the patella, usually with spontaneous reduction. Many predisposing conditions have been described, including trochlear dysplasia, excessive lateral patellar tilt, patella alta and lateralization of the tibial tuberosity. Associated injuries are bone bruises of the patella and lateral femoral condyle, tears of the medial retinaculum that include the medial patellofemoral ligament (MPFL), tears of the vastus medialis obliquus muscle, injuries of articular cartilage, and intra-articular bodies. Children who are refractory to conservative management, have a large cartilage defect, or are at substantial risk for recurrent dislocations are candidates for surgical procedures to prevent future dislocations. Procedures can include MPFL repair or reconstruction, tibial tubercle repositioning and lateral retinacular release. The purpose of this review is to illustrate the imaging findings of transient patellar dislocation in the acute setting, the normal imaging appearance after surgical intervention, and post-surgical complications. (orig.)

  15. Cine MR imaging before and after realignment surgery for patellar maltracking - comparison with axial radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Brossmann, J. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Muhle, C. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Buell, C.C. [Rheumaklinik, Bad Bramstedt (Germany); Zieplies, J. [Lubinus Klinik, Kiel (Germany); Melchert, U.H. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Brinkmann, G. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Schroeder, C. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik der Univ. Kiel (Germany)

    1995-04-01

    Comparison of motion-triggered cine magnetic resonance (MR) imaging and conventional radiographs for the assessment of operative results of patellar realignment. Fifteen patients with recurrent patellar dislocation or patellar subluxation were evaluated with conventional axial radiographs before and after realignment surgery by measuring the congruence angle (CA), lateral patellofemoral angle (LPFA), and lateral displacement (d). In eight patients the patellofemoral joint was additionally evaluated pre- and postoperatively with motion-triggered cine MR imaging by determining the bisect offset (BSO), lateral patellar displacement (LPD), and patellar tilt angle (PTA). Significant differences between the pre- and postoperative measurements were found for all MR imaging parameters (BSO, LPD, PTA: p<0.01) but not for the conventional X-ray parameters (CA: p=0.70, LPFA: p=0.56; d: p=0.04). Motion-triggered cine MR imaging was superior to conventional tangential radiographs for assessing the effectiveness of patellar realignment surgery. (orig.)

  16. Cine MR imaging before and after realignment surgery for patellar maltracking - comparison with axial radiographs

    International Nuclear Information System (INIS)

    Brossmann, J.; Muhle, C.; Buell, C.C.; Zieplies, J.; Melchert, U.H.; Brinkmann, G.; Schroeder, C.; Heller, M.

    1995-01-01

    Comparison of motion-triggered cine magnetic resonance (MR) imaging and conventional radiographs for the assessment of operative results of patellar realignment. Fifteen patients with recurrent patellar dislocation or patellar subluxation were evaluated with conventional axial radiographs before and after realignment surgery by measuring the congruence angle (CA), lateral patellofemoral angle (LPFA), and lateral displacement (d). In eight patients the patellofemoral joint was additionally evaluated pre- and postoperatively with motion-triggered cine MR imaging by determining the bisect offset (BSO), lateral patellar displacement (LPD), and patellar tilt angle (PTA). Significant differences between the pre- and postoperative measurements were found for all MR imaging parameters (BSO, LPD, PTA: p<0.01) but not for the conventional X-ray parameters (CA: p=0.70, LPFA: p=0.56; d: p=0.04). Motion-triggered cine MR imaging was superior to conventional tangential radiographs for assessing the effectiveness of patellar realignment surgery. (orig.)

  17. Proximal patellar tendinosis and abnormalities of patellar tracking

    International Nuclear Information System (INIS)

    Allen, G.M.; Tauro, P.G.; Ostlere, S.J.

    1999-01-01

    Objective. To assess whether an association exists between patellar tendinosis and abnormal patellar tracking. Design and patients. The MRI examinations of 630 patients (i.e. 860 knees) referred with anterior knee pain over a 4-year period were assessed in retrospect for the presence of patellar tendinosis and abnormal patellar tracking. The images of the patients with patellar tendinosis were reviewed and the location within the patellar tendon was recorded. Results. There were 44 knees with proximal patellar tendinosis. Twenty-four of these were considered to have normal patellar tracking and 20 to have abnormal patellar tracking. In the group of 816 knees without proximal patellar tendinosis, 581 were considered to have normal patellar tracking and 235 knees to have abnormal patellar tracking. When the two groups were compared there was a statistically significant difference in the ratio of patients with and without abnormal tracking. Conclusion. In patients referred with anterior knee pain or suspected abnormal patellar tracking there is a significant association between proximal patellar tendinosis and abnormal patellar tracking. (orig.)

  18. Estudo prospectivo randomizado sobre a luxação traumática de patela: tratamento conservador versus reconstrução do ligamento femoropatelar medial com tendão patelar - mínimo de dois anos de seguimento Randomized prospective study on traumatic patellar dislocation: conservative treatment versus reconstruction of the medial patellofemoral ligament using the patellar tendon, with a minimum of two years of follow-up

    Directory of Open Access Journals (Sweden)

    Alexandre Carneiro Bitar

    2011-01-01

    Full Text Available OBJETIVO: O objetivo deste estudo foi comparar os resultados da cirurgia (reconstrução do ligamento femoropatelar medial; LFPM com os resultados do tratamento conservador da luxação primária de patela. MÉTODOS: Trinta e nove pacientes (41 joelhos com luxação de patela foram randomizados em dois grupos (um grupo foi tratado conservadoramente - imobilização e fisioterapia - e o outro cirurgicamente com a reconstrução do LFPM e foram avaliados com um seguimento mínimo de dois anos. O questionário de Kujala foi aplicado para avaliar dor e qualidade de vida e as recidivas foram avaliadas. Os testes do Qui-quadrado de Pearson e exato de Fisher foram utilizados na avaliação estatística. RESULTADOS: A análise estatística mostrou que a média do escore de Kujala foi significativamente mais baixa no grupo conservador (70,8 quando comparada à média do grupo cirúrgico (88,9, com p = 0,001. O grupo cirúrgico apresentou maior porcentagem de resultados bom/excelente (71,43% no escore de Kujala quando comparados ao grupo conservador (25% com p = 0,003. O grupo conservador apresentou um número maior de recorrências (35% dos casos, enquanto que no grupo cirúrgico não houve relatos de recorrências e/ou subluxações. CONCLUSÕES: O tratamento com a reconstrução do ligamento femoropatelar medial com o tendão patelar produziu melhores resultados, com base na análise das recorrências pós-tratamento e nos resultados finais melhores no questionário de Kujala após um seguimento mínimo de dois anos.OBJECTIVE: The aim of this study was to compare the surgical results from reconstruction of the medial patellofemoral ligament (MPFL with non-operative treatment of primary patellar dislocation. METHODS: Thirty-nine patients (41 knees with patellar dislocation were randomized into two groups. One group was treated conservatively (immobilization and physiotherapy and other was treated surgically with reconstruction of the MPFL, and the

  19. Patellar subluxation syndrome. Observation of the patellofemoral joint using CT-scan

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Tomonori; Sasaki, Tetsuto; Susuda, Koichi; Moji, Junichi (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1983-10-01

    Clinical symptoms of patellar subluxation syndrome associated with pain were investigated for 24 knees of 20 patients, and the state of patella dislocation was observed by CT-scan. The patients had high incidence of an apprehension sign, showing their fear of patellar luxation. Many of them complained of patello-femoral joint pain due to chondromalacia patellae. In order to derive patellar subluxation, the method of CT-Q-contraction was carried out at the extended position of the patellar joint. In patients with patellar subluxation syndrome, the rate of shift in the diseased side was significantly higher than that of the other side, suggesting decreased muscular strength of the musculus vastus of the diseased side. Improvement of the symptoms was seen in all except one of 12 knees operated by the combined method of Green's method with Blauth's more than 6 months before. Availability of this operation was verified by the CT-Q-contraction.

  20. Kinematic MR imaging of the knee for evaluating patellar tracking

    International Nuclear Information System (INIS)

    Shellock, F.G.; Mink, J.H.; Fox, J.

    1988-01-01

    A new technique to evaluate patellar tracking uses MR imaging and a specially designed positioning device (MEDRAD). T1-weighted, axial plane imaging was performed on both knees at the following joint angles: 0 0 , 5 0 , 10 0 , 15 0 , 20 0 , 25 0 , and 30 0 . The total examination time was approximately 12 minutes. Images were viewed in a cine loop to produce a kinematic study that depicted the relationship of the patella to the trochlear groove during the different angles of knee flexion. To date, 102 subjects (204 knees) have been examined. Dislocation, subluxatino, lateral tilt, lateral and medial displacement of the patella, and normal patellar tracking could all be identified with this technique. Abnormal configurations of the patella and/or trochlear groove were also clearly demonstrated. In conclusion, kinematic MR imaging of the knee provided important clinical information concerning patellar tracking and other related abnormalities of the patellofemoral joint

  1. Simultaneous bilateral patellar tendon rupture ?

    OpenAIRE

    Moura, Diogo Lino; Marques, Jos? Pedro; Lucas, Francisco Manuel; Fonseca, Fernando Pereira

    2016-01-01

    Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a s...

  2. What is the chance that a patella dislocation will happen a second time: update on the natural history of a first time patella dislocation in the adolescent.

    Science.gov (United States)

    Seitlinger, Gerd; Ladenhauf, Hannah N; Wierer, Guido

    2018-02-01

    Patellar instability occurs mainly in young patients and shows a high incidence of concomitant cartilage injuries. Recently there has been a strong attempt to identify risk factors and enhance imaging techniques to detect patients with an increased risk for recurrent patella dislocation.We describe current findings on factors associated with recurrent patella dislocation in the adolescent. Trochlear dysplasia, patellar height, patellar tilt, tibial tuberosity-trochlear groove distance, skeletal maturity, and history of contralateral patellar dislocation are well known significant risk factors for recurrence in adolescent patients. Predictive models to calculate risk of recurrence have been reported recently. The Patellar Instability Severity Score was the first to include demographic and anatomic factors, which is of major value when counseling patients and relatives. Several classification systems to predict the rate of recurrence after primary patella dislocation have been presented over the last years. Anatomic risk factors such as skeletal immaturity, trochlear morphology, patellar height, patellar tilt, and elevated tibial tuberosity-trochlear groove distance have been investigated. However, there is still a lack of knowledge as to how single risk factors or their interaction with each other may contribute.

  3. Patellar osteochondroma: case report,

    Directory of Open Access Journals (Sweden)

    Frederico Barra de Moraes

    2014-04-01

    Full Text Available The aim was to report on a rare case of patellar osteochondroma. A 60-year-old man presented a tumor on his left patella that had developed over a 10-year period, which is a rare occurrence, considering the patient's age and the site at which the tumor appeared. The clinical condition comprised mild pain and the presence of a mass, without limitation of flexion-extension or any neurovascular deficit. The tumor dimensions were 8 cm longitudinally × 6 cm transversally × 3 cm anteroposteriorly. It was hardened and was adhering to the patellar bone plane. On radiographs and tomographic scans, we observed areas of greater density corresponding to bone and other less dense areas that could correspond to slow-growing cartilage, with irregularities on the patellofemoral joint surface. Simple resection of the tumor was performed, and the anatomopathological examination confirmed that it was a patellar osteochondroma. Osteochondroma, or osteocartilaginous exostosis, includes a large proportion of the benign bone tumors. It results from cell alterations that trigger unregulated production of spongy bone. It is basically treated by means of surgical removal of the tumor mass. This is not essential, but is recommended in order to avoid lesions caused by contiguity and the risk of malignant transformation.

  4. 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.

  5. Adolescent patellar instability: current concepts review.

    Science.gov (United States)

    Clark, D; Metcalfe, A; Wogan, C; Mandalia, V; Eldridge, J

    2017-02-01

    Patellar instability most frequently presents during adolescence. Congenital and infantile dislocation of the patella is a distinct entity from adolescent instability and measurable abnormalities may be present at birth. In the normal patellofemoral joint an increase in quadriceps angle and patellar height are matched by an increase in trochlear depth as the joint matures. Adolescent instability may herald a lifelong condition leading to chronic disability and arthritis. Restoring normal anatomy by trochleoplasty, tibial tubercle transfer or medial patellofemoral ligament (MPFL) reconstruction in the young adult prevents further instability. Although these techniques are proven in the young adult, they may cause growth arrest and deformity where the physis is open. A vigorous non-operative strategy may permit delay of surgery until growth is complete. Where non-operative treatment has failed a modified MPFL reconstruction may be performed to maintain stability until physeal closure permits anatomical reconstruction. If significant growth remains an extraosseous reconstruction of the MPFL may impart the lowest risk to the physis. If minor growth remains image intensifier guided placement of femoral intraosseous fixation may impart a small, but acceptable, risk to the physis. This paper presents and discusses the literature relating to adolescent instability and provides a framework for management of these patients. Cite this article: Bone Joint J 2017;99-B:159-70. ©2017 The British Editorial Society of Bone & Joint Surgery.

  6. Simultaneous bilateral patellar tendon rupture.

    Science.gov (United States)

    Moura, Diogo Lino; Marques, José Pedro; Lucas, Francisco Manuel; Fonseca, Fernando Pereira

    2017-01-01

    Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

  7. Simultaneous bilateral patellar tendon rupture

    Directory of Open Access Journals (Sweden)

    Diogo Lino Moura

    Full Text Available ABSTRACT Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

  8. [Elbow dislocation].

    Science.gov (United States)

    de Pablo Márquez, B; Castillón Bernal, P; Bernaus Johnson, M C; Ibañez Aparicio, N M

    Elbow dislocation is the most frequent dislocation in the upper limb after shoulder dislocation. Closed reduction is feasible in outpatient care when there is no associated fracture. A review is presented of the different reduction procedures. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Subtalar dislocation

    International Nuclear Information System (INIS)

    El-Khoury, G.Y.; Yousefzadeh, D.K.; Mulligan, G.M.; Moore, T.E.

    1982-01-01

    Over a period of three years we have seen nine patients with subtalar dislocation, all of whom sustained violent trauma to the region of the ankle and hind foot. All but one patient were males. Clinically a subtalar dislocation resembles a complicated fracture dislocation of the ankle but a definitive diagnosis can only be made radiographically. The mechanism of injury and radiographic features of this injury are discussed. (orig.)

  10. Jumper's Knee (Patellar Tendonitis) (For Parents)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Jumper's Knee (Patellar Tendonitis) KidsHealth / For Parents / Jumper's Knee (Patellar ... prevent continued damage to the knee. How the Knee Works To understand how jumper's knee happens, it ...

  11. Patellar Tendinopathy: Diagnosis and Treatment.

    Science.gov (United States)

    Figueroa, David; Figueroa, Francisco; Calvo, Rafael

    2016-12-01

    Patellar tendinopathy is a common cause of pain in athletes' knees. Historically, it has been related to jumping sports, such as volleyball and basketball. Repetitive jumping generates a considerable load of energy in the extensor mechanism, leading to symptoms. The main pathophysiologic phenomenon in patellar tendinopathy is tendinosis, which is a degenerative disorder rather than an inflammatory disorder; therefore, the other popular term for this disease, tendinitis, is not appropriate. The nonsurgical treatment of patellar tendinopathy is focused on eccentric exercises and often has good results. Other experimental options, with variable levels of evidence, are available for recalcitrant cases. Surgical treatment is indicated for cases that are refractory to nonsurgical treatment. Open or arthroscopic surgery can be performed; the two methods are comparable, but arthroscopic surgery results in a faster recovery time.

  12. Evaluation and Management of Patellar Instability in Pediatric and Adolescent Athletes

    OpenAIRE

    Khormaee, Sariah; Kramer, Dennis E.; Yen, Yi-Meng; Heyworth, Benton E.

    2015-01-01

    Context: The rising popularity and intensity of youth sports has increased the incidence of patellar dislocation. These sports-related injuries may be associated with significant morbidity in the pediatric population. Treatment requires understanding and attention to the unique challenges in the skeletally immature patient. Evidence Acquisition: PubMed searches spanning 1970-2013. Study Design: Clinical review. Level of Evidence: Level 5. Results: Although nonoperative approaches are most oft...

  13. Tendinopatia patelar Patellar tendinopathy

    Directory of Open Access Journals (Sweden)

    Moisés Cohen

    2008-08-01

    Full Text Available A tendinopatia do patelar ou jumper's knee (joelho do saltador é uma afecção que acomete freqüentemente atletas praticantes de atividades de salto ou aquelas que exigem força de impacto repetitivo. Histologicamente, a sobrecarga excessiva no tendão pode provocar alterações na matriz extracelular, resultando em pequenas lesões que, cronicamente, poderão levar a um quadro de tendinose, principalmente na região do pólo inferior da patela. A dor na região anterior do joelho é o primeiro sintoma relatado pelo paciente portador dessa afecção. Seu início é insidioso e gradual, principalmente após atividade física, mas, com a progressão da doença, pode tornar-se freqüente durante ou já no início da atividade. O diagnóstico de tendinopatia do patelar é eminentemente clínico, caracterizado por dor à palpação no pólo inferior da patela e adjacências e, nos casos mais avançados, nódulo palpável e edema associado podem ser visualizados. Exames complementares, como radiografia, ultra-sonografia (US e ressonância magnética (RM auxiliam no diagnóstico. O US e a RM são os mais indicados, pois podem definir o local exato da lesão, sua extensão, como também identificar a presença ou não de alterações degenerativas, sendo a RM o que fornece melhor resolução. O tratamento inicial da tendinopatia é clínico, com repouso relativo, correção dos fatores etiológicos, além de crioterapia e medidas fisioterápicas. A utilização da medicação analgésica e antiinflamatória é controversa. Nos casos que não respondem ao tratamento clínico, o cirúrgico é opção, e várias técnicas são descritas, a literatura demonstrando índices variados de bons resultados.Patellar tendinopathy, or jumper's knee, is often seen in athletes that practice jumping modalities, or modalities that require repetitive impact strength. Histologically, the excessive load on the tendon may cause changes in the extracellular matrix and

  14. Perilunate Dislocation

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    John Jiao

    2016-09-01

    Full Text Available History of present illness: A 25-year-old female presented to the emergency department with left wrist pain following a fall off a skateboard. The patient fell on her outstretched left wrist with the wrist dorsiflexed and reported immediate sharp pain to her left wrist that was worse with movement. She denied other trauma. Significant findings: In the left lateral wrist x-ray, the lunate (outlined in blue is dislocated from the rest of the wrist bones (yellow line but still articulates with the radius (red line. The capitate (yellow line does not sit within the distal articulation of the lunate and is displaced dorsally. Additionally, a line drawn through the radius and lunate (green line fails to intersect with the capitate. This is consistent with a perilunate dislocation. This is compared to a lunate dislocation, where the lunate itself is displaced and turned ventrally (spilled teacup and the proximal aspect does not articulate with the radius. Discussion: A perilunate dislocation is a significant closed wrist injury that is easily missed on standard anterior-posterior imaging. These dislocations are relatively rare, involving only 7% of all carpal injuries and are associated with high-energy trauma onto a hyperextended wrist, such as falls from a height, motor vehicle accidents, and sports injuries.1 An untreated perilunate dislocation is associated with high risk of chronic carpal instability and post-traumatic arthritis. If the mechanism of injury is sufficient to suspect perilunate dislocation, multiple radiographic views of the wrist should be ordered. Patients should receive prompt orthopedic consultation for open reduction and ligamentous repair. Even after successful identification and subsequent surgical repair, median nerve neuropathy and post-traumatic arthritis are frequent.2-3

  15. Non-Traumatic Anterior Dislocation of a Total Knee Replacement Associated with Neurovascular Injury

    Science.gov (United States)

    Aderinto, Joseph; Gross, Allan E; Rittenhouse, Bryan

    2009-01-01

    Prosthetic total knee replacements rarely dislocate. When dislocation does occur, it is usually in a posterior direction in association with a posterior stabilised, cruciate-sacrificing prosthesis. Neurovascular injury is unusual. In this report, we describe a case of anterior dislocation of a cruciate-retaining total knee replacement in a 67-year-old woman. The dislocation occurred in the absence of overt trauma and resulted in severe neurovascular injury. PMID:19686618

  16. Effect of patellar strap and sports tape on pain in patellar tendinopathy: A randomized controlled trial

    NARCIS (Netherlands)

    de Vries, A.; Zwerver, J.; Diercks, R.; Tak, I.; van Berkel, S.; van Cingel, R.; van der Worp, H.; van den Akker-Scheek, I.

    2016-01-01

    Numerous athletes with patellar tendinopathy (PT) use a patellar strap or sports tape during sports. This study's aim was to investigate the short-term effect of these orthoses on patellar tendon pain. Participants performed the single-leg decline squat, vertical jump test, and triple-hop test under

  17. Effect of patellar strap and sports tape on pain in patellar tendinopathy : A randomized controlled trial

    NARCIS (Netherlands)

    Vries , de A.; Zwerver, J.; Diercks, R.; Tak, I.; van Berkel, S.; van Cingel, R.; van der Worp, H.; van den Akker-Scheek, I.

    2016-01-01

    Numerous athletes with patellar tendinopathy (PT) use a patellar strap or sports tape during sports. This study's aim was to investigate the short-term effect of these orthoses on patellar tendon pain. Participants performed the single-leg decline squat, vertical jump test, and triple-hop test under

  18. Influence of Total Knee Arthroplasty on Patellar Kinematics and Patellofemoral Pressure.

    Science.gov (United States)

    Tanikawa, Hidenori; Tada, Mitsunori; Harato, Kengo; Okuma, Kazunari; Nagura, Takeo

    2017-01-01

    Patellofemoral complications are one of the main problems after total knee arthroplasty (TKA). The design of the TKA component may affect the patellar biomechanics, which may be associated with this postoperative complication. The purpose of this study was to assess the influence of TKA and prosthesis designs on the patellar kinematics and patellofemoral pressure. Using fresh-frozen cadavers, we measured the patellofemoral pressure, patella offset, and patella tilt in the following 4 conditions: normal knee (patella replacement only), cruciate-retaining TKA, condylar-stabilizing TKA, and posterior-stabilized TKA. The patellofemoral pressure increased significantly after the cruciate-retaining TKA and condylar-stabilizing TKA compared with the normal knee. The patella offset in the normal knee decreased with increasing knee flexion angles, while the patella offset in the TKA knees did not change significantly through the full range of motion. The amount of lateral patella tilt in the normal knee was significantly larger than the TKA knees in the full range of motion. Although the femoral components are designed to reproduce an anatomical patellar tracking, the physiological patellar kinematics were not observed. Relatively high patellofemoral pressure and kinematic change after TKA may be associated with postoperative complications such as the anterior knee pain. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Patellar tendinopathy : physical therapy and injection treatments

    NARCIS (Netherlands)

    van Ark, Mathijs

    2015-01-01

    Patellar tendinopathy, commonly known as jumper’s knee, is an overuse injury of the patellar tendon. It is a frequent injury, particularly in jumping athletes such as volleyball and basketball players. Jumper’s knee is often a long-lasting injury and can have a major impact on sports and even work

  20. Does patellar rim electrocautery have deleterious effects on patellar cartilage?

    Science.gov (United States)

    Namazi, Niloofar; Jaberi, Fereidoon Mojtahed; Pakbaz, Sara; Vosoughi, Amir Reza; Jaberi, Mahrad Mojtahed

    2014-03-01

    Circumpatellar electrocauterization to destroy pain receptors during total knee arthroplasty without patellar resurfacing is commonly used to decrease postoperative knee pain. We aimed to evaluate the effect of denervation with electrocauterization on patellar cartilage. Twenty rabbits were randomly assigned to two equally sized case and control groups. The rabbits in the case group underwent surgery via the anterior midline skin incision and medial parapatellar arthrotomy, followed by denervation electrocauterization at a depth of 1 mm and a distance of 3 mm from the outer border of the patella. In the control group, surgery was identical to that performed in the case group, but without patellar denervation. Twelve weeks after surgery, all rabbits were sacrificed. Range of motion, macroscopic evaluation of cartilage using modified Outerbridge scoring, and histopathological assessment using a modified histologic scoring system for cartilage were evaluated. Three rabbits died during the study. Nine cases and eight animals from the control group were included in the final evaluation. All rabbits had passive full range of motion. Mean Outerbridge score was 2.0 in the case group and 0.37 in the control group (p=0.002). There were statistically significant differences in cellularity (p=0.016), loss of matrix (p=0.004), and clustering of chondrocytes (p=0.008) between the two groups. Microscopic variables as a whole were statistically significant (p=0.001). Circumpatellar electrocauterization may result in cartilage destruction. So, we encourage caution in using routine electrocauterization in patients undergoing total knee arthroplasty. level II. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Routine patellar resurfacing using an inset patellar technique.

    LENUS (Irish Health Repository)

    Hurson, Conor

    2012-02-01

    The management of the patella in total knee arthroplasty still causes controversy. Whether or not to resurface the patella in primary total knee arthroplasty remains unclear. In this study we examined 220 consecutive total knee replacements, by a single surgeon, where the patella was routinely resurfaced using the inset technique. All patellae were suitable for resurfacing. Patellar thickness was not altered in 54.5% of patellae. In 97.2% the patella was within 2 mm of the original thickness. There were no significant complications. In this study we have found that the inset technique of patella resurfacing in total knee replacement is a simple and safe resurfacing procedure.

  2. Axial linear patellar displacement: a new measurement of patellofemoral congruence.

    Science.gov (United States)

    Urch, Scott E; Tritle, Benjamin A; Shelbourne, K Donald; Gray, Tinker

    2009-05-01

    The tools for measuring the congruence angle with digital radiography software can be difficult to use; therefore, the authors sought to develop a new, easy, and reliable method for measuring patellofemoral congruence. The abstract goes here and covers two columns. The abstract goes The linear displacement measurement will correlate well with the congruence angle measurement. here and covers two columns. Cohort study (diagnosis); Level of evidence, 2. On Merchant view radiographs obtained digitally, the authors measured the congruence angle and a new linear displacement measurement on preoperative and postoperative radiographs of 31 patients who suffered unilateral patellar dislocations and 100 uninjured subjects. The linear displacement measurement was obtained by drawing a reference line across the medial and lateral trochlear facets. Perpendicular lines were drawn from the depth of the sulcus through the reference line and from the apex of the posterior tip of the patella through the reference line. The distance between the perpendicular lines was the linear displacement measurement. The measurements were obtained twice at different sittings. The observer was blinded as to the previous measurements to establish reliability. Measurements were compared to determine whether the linear displacement measurement correlated with congruence angle. Intraobserver reliability was above r(2) = .90 for all measurements. In patients with patellar dislocations, the mean congruence angle preoperatively was 33.5 degrees , compared with 12.1 mm for linear displacement (r(2) = .92). The mean congruence angle postoperatively was 11.2 degrees, compared with 4.0 mm for linear displacement (r(2) = .89). For normal subjects, the mean congruence angle was -3 degrees and the mean linear displacement was 0.2 mm. The linear displacement measurement was found to correlate with congruence angle measurements and may be an easy and useful tool for clinicians to evaluate patellofemoral

  3. Verge of Collapse: The Pros/thesis of Art Research

    Science.gov (United States)

    Garoian, Charles R.

    2008-01-01

    This article explores "prosthesis" as a metaphor of embodiment in art-based research to challenge the utopian myth of wholeness and normality in art and the human body. Bearing in mind the correspondences between amputated bodies and the cultural dislocations of art, I propose "prosthetic epistemology" and "prosthetic ontology" as embodied knowing…

  4. [Treatment options for patellar tendinopathy].

    Science.gov (United States)

    Duthon, V B; Borloz, S; Ziltener, J-L

    2012-07-25

    Patellar tendinopathy is also called jumper's knee because of its high incidence in athletes with jumping or cutting activities as soccer, basketball, volleyball. Many different treatment methods have been described. However, no consensus exists regarding the optimal treatment for this condition. According to the literature, eccentric exercise-based physical therapy should be proposed first because of its strong scientific evidence. Shockwave therapy and injections may be useful but their real efficacy still has to be proven by randomized controlled study. For patients recalcitrant to more conservative options, operative management may be indicated.

  5. The patellofemoral joint: from dysplasia to dislocation

    Science.gov (United States)

    Zaffagnini, Stefano; Grassi, Alberto; Zocco, Gianluca; Rosa, Michele Attilo; Signorelli, Cecilia; Muccioli, Giulio Maria Marcheggiani

    2017-01-01

    Patellofemoral dysplasia is a major predisposing factor for instability of the patellofemoral joint. However, there is no consensus as to whether patellofemoral dysplasia is genetic in origin, caused by imbalanced forces producing maltracking and remodelling of the trochlea during infancy and growth, or due to other unknown and unexplored factors. The biomechanical effects of patellofemoral dysplasia on patellar stability and on surgical procedures have not been fully investigated. Also, different anatomical and demographic risk factors have been suggested, in an attempt to identify the recurrent dislocators. Therefore, a comprehensive evaluation of all the radiographic, MRI and CT parameters can help the clinician to assess patients with primary and recurrent patellar dislocation and guide management. Patellofemoral dysplasia still represents an extremely challenging condition to manage. Its controversial aetiology and its complex biomechanical behaviour continue to pose more questions than answers to the research community, which reflects the lack of universally accepted guidelines for the correct treatment. However, due to the complexity of this condition, an extremely personalised approach should be reserved for each patient, in considering and addressing the anatomical abnormalities responsible for the symptoms. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160081. Originally published online at www.efortopenreviews.org PMID:28630757

  6. Proximo-distal patellar position in three small dog breeds with medial patellar luxation.

    Science.gov (United States)

    Wangdee, C; Theyse, L F H; Hazewinkel, H A W

    2015-01-01

    Medial patellar luxation is thought to be associated with a high proximal position of the patella in the trochlear groove. To determine whether the ratio of patellar ligament length and patellar length (L:P) is influenced by the stifle angle (75°, 96°, 113°, 130°, and 148°) in small dog breeds and to compare the L:P ratio in dogs of three small dog breeds with and without medial patellar luxation. A mediolateral radiograph of the stifle joint was used to measure the L:P ratio in the stifle joints of dogs of three small breeds with and without medial patellar luxation. The L:P ratio was evaluated at five stifle angles (75°, 96°, 113°, 130°, and 148°) in 14 cadavers (26 stifle joints) of small dog breeds in order to identify the best stifle angle to measure the L:P ratio. Then the mean ± SD L:P ratio was calculated for normal stifles and stifles with medial patellar luxation grades 1, 2, and 3 in 194 Pomeranians, 74 Chihuahuas, and 41 Toy or Standard Poodles. The L:P ratio was the same for all five stifle angles in the cadavers (p = 0.195). It was also not significantly different in the three breeds (p = 0.135), in normal and medial patellar luxation-affected stifles overall (p = 0.354), and in normal and medial patellar luxation-affected joints within each breed (p = 0.19). We conclude that a proximo-distal patellar position is not associated with medial patellar luxation in Pomeranians, Chihuahuas, and Toy or Standard Poodles. Thus a longer patellar ligament length does not play a role in the pathophysiology of medial patellar luxation in these small dog breeds.

  7. Patellar tendinopathy: physical therapy and injection treatments

    OpenAIRE

    van Ark, Mathijs

    2015-01-01

    Patellar tendinopathy, commonly known as jumper’s knee, is an overuse injury of the patellar tendon. It is a frequent injury, particularly in jumping athletes such as volleyball and basketball players. Jumper’s knee is often a long-lasting injury and can have a major impact on sports and even work participation. The development of jumper’s knee and the best treatment for it are still unclear. The general aim of this thesis was to investigate the development and management of patellar tendinop...

  8. Does the grading of chondromalacia patellae influence anterior knee pain following total knee arthroplasty without patellar resurfacing?

    Science.gov (United States)

    Zha, Guo-Chun; Feng, Shuo; Chen, Xiang-Yang; Guo, Kai-Jin

    2018-03-01

    The influence of chondromalacia patellae (CMP) on post-operative anterior knee pain (AKP) following total knee arthroplasty (TKA) remains controversial, and few studies have focused on the relationship between them. The purpose of this study was to determine whether different CMP grades affect the incidence of AKP after TKA without patellar resurfacing. We performed a retrospective analysis of prospectively collected data on 290 TKAs with the use of the low contact stress mobile-bearing prosthesis, without patellar resurfacing in 290 patients from February 2009 to January 2013. Patients were assessed by the Outerbridge classification for CMP, visual analog scale for AKP, the Knee Society clinical scoring system of knee score (KS), function score (FS), the patellar score (PS) for clinical function, and patients' satisfaction. The intra-operative grading of CMP: grade I in 30 patients, grade II in 68 patients, grade III in 97 patients, and grade IV in 95 patients. The incidence of AKP at 36-month follow-up was 10.3% (30/290). No statistical difference was detected among the different CMP grades in terms of the incidence of AKP (p = 0.995), patients' satisfaction (p = 0.832), KS (p = 0.228), FS (p = 0.713), and PS (p = 0.119) at 36-month follow-up. The findings may suggest no relevant influence of CMP grading on the incidence of AKP after TKA without patellar resurfacing.

  9. The reliability and validity of radiological assessment for patellar instability. A systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Toby O. [University of East Anglia, Faculty of Health, Norwich (United Kingdom); Davies, Leigh [Norfolk and Norwich University Hospital, Norwich (United Kingdom); Toms, Andoni P.; Donell, Simon T. [University of East Anglia, Faculty of Health, Norwich (United Kingdom); Norfolk and Norwich University Hospital, Norwich (United Kingdom); Hing, Caroline B. [St George' s Hospital, London (United Kingdom)

    2011-04-15

    To determine the discriminative validity and reliability of the evidence base using meta-analysis. A review of published sources using the databases AMED, CINHAL, EMBASE, MEDLINE, Scopus and the Cochrane Library, and for unpublished material was conducted. All studies assessing the reliability, validity, sensitivity or specificity of magnetic resonance imaging (MRI), computed tomography (CT) or ultrasound (US) of the patellofemoral joint of patients following patellar dislocation, subluxation or instability, were included. A meta-analysis was performed to assess the difference in radiological measurements between healthy controls and subjects with patellar instability in order to assess discrimination validity. A narrative assessment was used to evaluate the inter- and intra-observer reliability as well as the sensitivity and specificity of specific radiological measurements. A total of 27 studies were reviewed. The findings indicated that there was acceptable inter-observer and intra-observer reliability and validity for different methods of assessing patellar height and the sulcus angle with X-ray, MRI and CT methods, and the tibial tubercle-trochlear groove (TT-TG) assessed using CT. There was poor reliability or validity for the assessment of severity of trochlear dysplasia and the sulcus angle using US. There is insufficient evidence to determine the reliability, validity, sensitivity or specificity of tests such as the congruence angle, lateral patellar displacement, lateral patellar tilt, trochlear depth, boss height, the crossing sign or Wiberg patellar classification. A critical appraisal of the literature identified a number of recurrent methodological limitations. Further study is recommended to evaluate the reliability and validity of these radiological outcomes using well-designed radiological trials. (orig.)

  10. The reliability and validity of radiological assessment for patellar instability. A systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Smith, Toby O.; Davies, Leigh; Toms, Andoni P.; Donell, Simon T.; Hing, Caroline B.

    2011-01-01

    To determine the discriminative validity and reliability of the evidence base using meta-analysis. A review of published sources using the databases AMED, CINHAL, EMBASE, MEDLINE, Scopus and the Cochrane Library, and for unpublished material was conducted. All studies assessing the reliability, validity, sensitivity or specificity of magnetic resonance imaging (MRI), computed tomography (CT) or ultrasound (US) of the patellofemoral joint of patients following patellar dislocation, subluxation or instability, were included. A meta-analysis was performed to assess the difference in radiological measurements between healthy controls and subjects with patellar instability in order to assess discrimination validity. A narrative assessment was used to evaluate the inter- and intra-observer reliability as well as the sensitivity and specificity of specific radiological measurements. A total of 27 studies were reviewed. The findings indicated that there was acceptable inter-observer and intra-observer reliability and validity for different methods of assessing patellar height and the sulcus angle with X-ray, MRI and CT methods, and the tibial tubercle-trochlear groove (TT-TG) assessed using CT. There was poor reliability or validity for the assessment of severity of trochlear dysplasia and the sulcus angle using US. There is insufficient evidence to determine the reliability, validity, sensitivity or specificity of tests such as the congruence angle, lateral patellar displacement, lateral patellar tilt, trochlear depth, boss height, the crossing sign or Wiberg patellar classification. A critical appraisal of the literature identified a number of recurrent methodological limitations. Further study is recommended to evaluate the reliability and validity of these radiological outcomes using well-designed radiological trials. (orig.)

  11. Radiographic Features of Acute Patellar Tendon Rupture.

    Science.gov (United States)

    Fazal, Muhammad Ali; Moonot, Pradeep; Haddad, Fares

    2015-11-01

    The purpose of our study was to assess soft tissue features of acute patellar tendon rupture on lateral knee radiograph that would facilitate early diagnosis. The participants were divided into two groups of 35 patients each. There were 28 men and seven women with a mean age of 46 years in the control group and 26 men and nine women with a mean age of 47 years in the rupture group. The lateral knee radiograph of each patient was evaluated for Insall-Salvati ratio for patella alta, increased density of the infrapatellar fat pad, appearance of the soft tissue margin of the patellar tendon and bony avulsions. In the rupture group there were three consistent soft tissue radiographic features in addition to patellar alta. These were increased density of infrapatellar fat pad; loss of sharp, well-defined linear margins of the patellar tendon and angulated wavy margin of the patellar tendon while in the control group these features were not observed. The soft tissue radiographic features described in the rupture group are consistent and reliable. When coupled with careful clinical assessment, these will aid in early diagnosis and further imaging will be seldom required. © 2015 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

  12. Comparison of patellar distraction with patellar glides in female patients with patellofemoral pain syndrom

    International Nuclear Information System (INIS)

    Syed, S.; Chaudhary, M.A.; Noor, R.; Bashir, M.S.; Manzoor, B.

    2017-01-01

    To analyse effectiveness of patellar glides and patellar distraction in the patients with patellofemoral pain syndrome (PFPS). Methodology: This longitudinal interventional comparative study was conducted at Physiotherapy Department, Mayo Hospital Lahore, Pakistan from September 2015 to March 2016. A total of 70 patients were divided into 2 groups randomly; group A received hot pack, quadriceps strengthening exercises and patellar distraction whereas group B received hot pack, quadriceps strengthening exercises and patellar glides. Age of the female patients was 18-40 years. Visual Analogue Scale (VAS) and Knee Injury and osteoarthritis outcome score (KOOS) questionnaire were used to compare the effectiveness of both treatments. The data were analysed using SPSS v. 21.0. Results: There was reduction in pain at VAS and KOOS showed improvement in function as well as the range of motion also increased in both groups. Both treatment techniques were effective in reducing pain in PFPS (P <0.005). Pre-treatment KOOS score in patellar glides group was 34.77+10.84 and post-treatment KOOS score was 62.155+15.75 and for patellar distraction group pre-treatment KOOS score was 35.42+10.07 that increased to 55.77+14.66 after treatment which showed that patellar glides had better effect on PFPS. Conclusion: Both treatments were effective in managing PFPS in terms of decreasing pain and increasing ROM as there was no significant difference between two techniques, however patellar glides were superior as compared to patellar distraction in decreasing pain and increasing ROM. (author)

  13. CT patellar cortex tilt angle: A radiological method to measure patellar tilt

    International Nuclear Information System (INIS)

    Mirza Toluei, F.; Afshar, A.; Salarilak, S.; Sina, A.

    2005-01-01

    Background/Objectives: the role of patellar tilt in the anterior knee pain is indisputable. Traditionally. the lateral patello-femoral angle of Laurin has been defined in both the axial view and CT images for measuring the tilt of patella. We present a new angle. which is independent of the morphology of patella and directly relates to clinical assessment of the tilt. which is appreciated from palpation of the edges of the patella. Patients and Methods: 38 patients with anterior knee pain and forty normal control subjects were examined using CT scan of patello-femoral joint in 15 degrees of knee flexion. The amount of lateral patellar tilt was quantitatively assessed using the lateral patello-femoral angle, as described by Laurin et al, and the newly defined patellar cortex tilt angle. This angle is subtended by the line drawn along the posterior femoral condyles and the one parallel to the subchondral bone of patellar cortex. The fifteen-degree tilt was taken as normal cut-off point for patellar cortex tilt angle in the control group. Results: in patients, the average tilt of patella. using the patellar cortex tilt angle was 15.26 versus 7.05 in the control group. Using Student's t test, the difference between the two means was significant (P<0.001). The sensitivity and specificity of patellar cortex tilt angle were 40 and 90 percent, respectively There was a moderate agreement between our presented test and the lateral tilt angle test (kappa=0.40. P<0.001). Conclusion: our results indicate that patellar tilt can also be detected using patellar cortex tilt angle. We need more specific studies ta determine the validity of the test

  14. The Angelchik prosthesis

    International Nuclear Information System (INIS)

    Fargnoli, R.; Bozza, A.; Magnoli, A.; Villari, N.; Pernice, L.M.; Andreoli, F.; Lombardi, P.

    1989-01-01

    The Angelchik prosthesis is used in the surgical treatment of gastroesophageal reflux. Operated patients are preliminary examined with imaging techniques, but manometric and acidometric techniques are also used. Although the conventional esophagogram still maintains its diagnostic significance, Computed Tomography (CT) has become the first-choice imaging modality. CT allows the correct evaluation of both the state of the prosthesis and its relationship to the esophagus and gastric fundus. The possible postoperative complications following an incorrect placement of the prosthesis can be accurately diagnosed too. The authors report their experience in the study of 5 patients examined with both conventional radiology and CT

  15. Lateral patellar luxation: magnetic resonance findings

    International Nuclear Information System (INIS)

    Armesto, V.; Pulpeiro, J.R.

    1995-01-01

    The objective of this article is to present the magnetic resonance (MR) findings associated with lateral patellar luxation. The series consisted of eight patients, all of whom presented joint effusion, damage to the medical retinaculum and cortical contusion or fracture of medical aspect of the patella or of anterolateral surface of the outer condyle. Five patients also presented patellar sub luxation. Diagnosis depends on the technique employed, with axial planes being very useful. Thus, it is recommended that they be used as the standard plane, especially in pathologies that are clinically unsuspicious as in this case. MR can also provide information that leads to surgical treatment rather than the standard conservative treatment. (Author)

  16. [Intra-prosthetic dislocation of the Bousquet dual mobility socket].

    Science.gov (United States)

    Lecuire, F; Benareau, I; Rubini, J; Basso, M

    2004-05-01

    The Bousquet system is a dual mobility head-polyethylene polyethylene-metal cup socket. The polyethylene insert retaining the femoral head moves in the noncemented metal cup, increasing both mobility and stability. Between 1989 and 1997, seven cases of intra-prosthetic dislocation (six patients) were observed. The femoral head escaped from the polyethylene insert due to wear. On the average, this complication occurred ten Years after implantation. Risk of dislocation was high in six of the seven hips. All patients had a large sized stem screwed into the femoral neck. There was a characteristic radiological aspect with loss of the concentric head metal cup configuration. The head was applied against the upper wall of the metal cup. Surgical replacement was undertaken early in six patients by simply changing the insert without modifying the other stable components. Outcome remained good at three to eight Years. One patient underwent late surgery. The insert and the cup were replaced with a classical implant. Functional outcome was good but recurrent dislocation occurred. At mid-term, intra-prosthetic dislocation of dual mobility sockets appears to be exceptional. Dislocation results from polyethylene wear leading to failure of the insert to retain the prosthetic head. Wear is favored by direct phenomena (direct contact between neck and insert which can occur early if there is a small difference in the head and neck diameters) or indirect phenomena (factors limiting polyethylene metal-cup mobility). Surgical treatment is necessary. If undertaken early, replacement with a modular head and insert can be sufficient if the prosthesis has not loosened but the metal cup may have to be replaced in the event of metal-metal contact between the head and the cup. Prosthesis loosening, wear of the metal cup, or an identified cause of dislocation imply replacing the failing implants. Implantation of the dual mobility system is particularly interesting for patients with a high risk

  17. Clinical Outcomes After Isolated Medial Patellofemoral Ligament Reconstruction for Patellar Instability Among Patients With Trochlear Dysplasia.

    Science.gov (United States)

    Liu, Joseph N; Brady, Jacqueline M; Kalbian, Irene L; Strickland, Sabrina M; Ryan, Claire Berdelle; Nguyen, Joseph T; Shubin Stein, Beth E

    2018-03-01

    Medial patellofemoral ligament (MPFL) reconstruction has become one of the most common and widely used procedures to regain stability among patients with recurrent lateral patellar dislocation. While recent studies demonstrated low recurrence rates, improved patient-reported outcome measures, and a high rate of return to sports, limited literature explored its effectiveness as an isolated intervention in the context of trochlear dysplasia. To determine the efficacy of isolated MPFL reconstruction in treating patellar instability in the setting of trochlear dysplasia. Case series; Level of evidence, 4. This was a retrospective review of consecutive patients who underwent uni- or bilateral medial patellofemoral ligament reconstruction for patellofemoral instability with a minimum 2-year follow-up. No osteotomies were included. Pre- and postoperative assessment included ligamentous laxity, patellar crepitus, tilt, translation, apprehension, and radiographic features, including tibial tubercle-trochlear groove (TT-TG) distance, Dejour classification, and Caton-Deschamps index. A total of 121 MPFL reconstructions were included. Mean age at surgery was 23.8 years, and 4.4 dislocation events occurred before surgery. Mean follow-up was 44 months; 76% of patients were female. Mean preoperative TT-TG ratio was 13.5, and mean Caton-Deschamps ratio was 1.2; 92% of patients had Dejour B, C, or D trochlear dysplasia. Kujala score improved from 55.0 preoperatively to 90.0 ( P patellofemoral instability, despite the presence of trochlear dysplasia. Most patients are able to return to sports by 1 year postoperatively at the same or higher level of play.

  18. Endoscopic removal of a dislocated tomour prothesis from the stomach

    International Nuclear Information System (INIS)

    Rueckauer, K.; Dinkel, E.

    1985-01-01

    Endoscopic pertubation of oesophagogustric neoplasms is an established method of palliative treatment. The dislocated plastic prosthesis may be removed with difficulties from the stomach endoscopically. A simple technique for endoscopic removal of the prosthesis is described. The tube can be precisely centred within the oesophageal lumen by use of an intestinal decompression tube and additional guidance by the endoscopic retraction forceps. Thus gross damge of the exophytic tumor tissue with bleeding or perforation sequelae can be avoided. Injury to the patient does not exceed that caused by an ordinary gastroscopy. (orig.) [de

  19. Computed tomographic evaluation of realignment surgery for patellar subluxation

    International Nuclear Information System (INIS)

    Inoue, Masahiro; Shino, Konsei; Maeda, Akira; Nakata, Ken; Ono, Hiroo.

    1994-01-01

    Forty-two patients with patellar subluxation underwent realignment surgery of the knee extensor mechanism. The surgery included, lateral release, advancement and reefing of the vastus medialis and the medial capsule and tibial tubercle transfer (Elmslie-Trillat procedure). The effect of surgery was evaluated using computed tomograms of the pre- and post-operative knees at 0, 15, 30 and 45 degrees of knee flexion. The degree of patellofemoral incongruence on CT was expressed using two parameters of patellar tilt and patellar shift. Thirty-three volunteers without any patello-femoral symptoms served as controls. Postoperatively both the patellar tilt and the patellar shift improved significantly. The average patellar tilt and the patellar shift of the patient group at 45 degrees were comparable with those of controls. However, it was found by CT that the realignment surgery was less effective between 0 and 30 degrees of knee flexion. (author)

  20. Computed tomographic evaluation of realignment surgery for patellar subluxation

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Masahiro (Kansai Rosai Hospital, Amagasaki (Japan)); Shino, Konsei; Maeda, Akira; Nakata, Ken; Ono, Hiroo

    1994-01-01

    Forty-two patients with patellar subluxation underwent realignment surgery of the knee extensor mechanism. The surgery included, lateral release, advancement and reefing of the vastus medialis and the medial capsule and tibial tubercle transfer (Elmslie-Trillat procedure). The effect of surgery was evaluated using computed tomograms of the pre- and post-operative knees at 0, 15, 30 and 45 degrees of knee flexion. The degree of patellofemoral incongruence on CT was expressed using two parameters of patellar tilt and patellar shift. Thirty-three volunteers without any patello-femoral symptoms served as controls. Postoperatively both the patellar tilt and the patellar shift improved significantly. The average patellar tilt and the patellar shift of the patient group at 45 degrees were comparable with those of controls. However, it was found by CT that the realignment surgery was less effective between 0 and 30 degrees of knee flexion. (author).

  1. Excessive lateral patellar translation on axial computed tomography indicates positive patellar J sign.

    Science.gov (United States)

    Xue, Zhe; Song, Guan-Yang; Liu, Xin; Zhang, Hui; Wu, Guan; Qian, Yi; Feng, Hua

    2018-03-20

    The purpose of the study was to quantify the patellar J sign using traditional computed tomography (CT) scans. Fifty-three patients (fifty-three knees) who suffered from recurrent patellar instability were included and analyzed. The patellar J sign was evaluated pre-operatively during active knee flexion and extension. It was defined as positive when there was obvious lateral patellar translation, and negative when there was not. The CT scans were performed in all patients with full knee extension; and the parameters including bisect offset index (BOI), patellar-trochlear-groove (PTG) distance, and patellar lateral tilt angle (PLTA) were measured on the axial slices. All the three parameters were compared between the J sign-positive group (study group) and the J sign-negative group (control group). In addition, the optimal thresholds of the three CT scan parameters for predicting the positive patellar J sign were determined with receiver operating characteristic (ROC) curves, and the diagnostic values were assessed by the area under the curve (AUC). Among the fifty-three patients (fifty-three knees), thirty-seven (70%) showed obvious lateral patellar translation, which were defined as positive J sign (study group), and the remaining sixteen (30%) who showed no lateral translation were defined as negative J sign (control group). The mean values of the three CT parameters in the study group were all significantly larger compared to the control group, including BOI (121 ± 28% vs 88 ± 12%, P = 0.038), PTG distance (5.2 ± 6.6 mm vs - 4.4 ± 5.2 mm, P J sign was 97.5% (Sensitivity = 83.3%, Specificity = 87.5%). In this study, the prevalence of positive patellar J sign was 70%. The BOI measured from the axial CT scans of the knee joint can be used as an appropriate predictor to differentiate the positive J sign from the negative J sign, highlighting that the excessive lateral patellar translation on axial CT scan indicates positive

  2. An Isolated Medial Patellofemoral Ligament Reconstruction with Patellar Tendon Autograft

    Directory of Open Access Journals (Sweden)

    Dariusz Witoński

    2013-01-01

    Full Text Available The aim of the study was to evaluate the results of the medial patellofemoral ligament reconstruction with a medial strip of patellar tendon autograft after a minimum 2-year followup. Ten patients (10 knees were operated on by one surgeon, according to the modified technique, described by Camanho, without any bone plug at free graft end. The mean age of the patients was 27.2 years (ranging from 18 to 42 years. The mean follow-up period was 3 years and 7 months. All patients were reviewed prospectively. At the last follow-up visit, all the patients demonstrated a significant improvement in terms of patellofemoral joint stability, all aspects of the KOOS questionnaire, and Kujala et al.’s score (59.7 points preoperatively and 84.4 points at the last followup. No patient revealed recurrent dislocation. The SF-36 score revealed a significant improvement in bodily pain, general health, physical role functioning, social role functioning, and physical functioning domains. The described MPFL reconstruction with the use of the medial 1/3rd of patella tendon is an effective procedure that gives satisfactorily patellofemoral joint functions, improves the quality of life, and provides much pain relief. It is relatively simple, surgically not extensive, and economically cost-effective procedure.

  3. Recession wedge trochleoplasty as an additional procedure in the surgical treatment of patellar instability with major trochlear dysplasia: early results.

    Science.gov (United States)

    Thaunat, M; Bessiere, C; Pujol, N; Boisrenoult, P; Beaufils, P

    2011-12-01

    The importance of a dysplastic trochlea as a component of patellar instability has long been recognized. An original trochleoplasty technique consisting in retro-trochlear recession wedge osteotomy was described by Goutallier et al. The aim is not to fashion a groove but to reduce the bump without modifying patellofemoral congruence. This retrospective study reports the operative technique and short-term outcomes of a consecutive case series of 17 patients (19 knees) who underwent recession wedge trochleoplasty for patellofemoral instability associated with severe trochlear dysplasia. Other contributing factors of patellar instability were also corrected as part of the surgical procedure: tibial tuberosity transfer (n=18), MPFL reconstruction (n=8). Minimum follow-up was 12 months (mean, 34 months; range, 12 to 71 months). The trochlear prominence was reduced from a mean 4.8mm (range, 0 to 8mm) to -0.8mm (range, -8 to 6mm). Patellar tilt was reduced from a mean 14° (range, 6° to 26°) to 6° (range, -1° to 24°). Two cases showed recurrent patellofemoral instability. Mean Kujala, KOOS and IKDC score were respectively 80 (± 17), 70 (± 18) and 67 (± 17) at last follow-up. Three patients required further operations, apart from removal of metal screws: arthroscopic arthrolysis for stiffness (n=1), revision for tibial tuberosity non-union (n=1), and supratrochlear exostosectomy (n=1). Recession wedge trochleoplasty is a feasible additional procedure addressing bony trochlear abnormality in the surgical treatment of patellar instability. Our attitude is to perform it never in isolation but associated to realignment of the extensor apparatus according to the à la carte surgery concept. It seems to be effective in preventing future patellar dislocation and reducing anterior knee pain in case of painful patellofemoral instability with a major dysplastic trochlea, or in revision cases when other realignment procedures have failed. Copyright © 2011 Elsevier Masson SAS

  4. Gene therapy and cement injection for the treatment of hip prosthesis loosening in elderly patients

    NARCIS (Netherlands)

    Poorter, Jolanda de

    2010-01-01

    Approximately one million total hip replacement operations are performed worldwide annually, mostly for osteoarthritis and rheumatoid arthritis. A major complication in total hip arthroplasties is loosening of the prosthesis leading to pain and walking difficulties and a higher risk for dislocations

  5. 21 CFR 888.3310 - Hip joint metal/polymer constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer constrained cemented or... Hip joint metal/polymer constrained cemented or uncemented prosthesis. (a) Identification. A hip joint... replace a hip joint. The device prevents dislocation in more than one anatomic plane and has components...

  6. Dislocation-dynamics method

    International Nuclear Information System (INIS)

    Van Brutzel, L.

    2015-01-01

    Dislocation-Dynamics (DD) technique is identified as the method able to model the evolution of material plastic properties as a function of the microstructural transformation predicted at the atomic scale. Indeed, it is the only simulation method capable of taking into account the collective behaviour of a large number of dislocations inside a realistic microstructure. DD simulations are based on the elastic dislocation theory following rules inherent to the dislocation core structure often call 'local rules'. All the data necessary to establish the local rules for DD have to come directly from experiment or alternatively from simulations carried out at the atomic scale such as molecular dynamics or ab initio calculations. However, no precise information on the interaction between two dislocations or between dislocations and defects induced by irradiation are available for nuclear fuels. Therefore, in this article the DD technique will be presented and some examples are given of what can be achieved with it. (author)

  7. Patellar tendinopathy - recent developments toward treatment.

    Science.gov (United States)

    Christian, Robert A; Rossy, William H; Sherman, Orrin H

    2014-01-01

    Patellar tendinopathy (PT) is a clinical and chronic overuse condition of unknown pathogenesis and etiology marked by anterior knee pain typically manifested at the inferior pole of the patella. PT has been referred to as "jumper's knee" since it is particularly common among populations of jumping athletes, such as basketball and volleyball players. Due to its common refractory response to conservative treatment, a variety of new treatments have emerged recently that include dry-needling, sclerosing injections, platelet-rich plasma therapy, arthroscopic surgical procedures, surgical resection of the inferior patellar pole, extracorporeal shock wave treatment, and hyperthermia thermotherapy. Since PT has an unknown pathogenesis and etiology, PT treatment is more a result of physician experience than evidence-based science. This review will summarize the current literature on this topic, identify current research efforts aimed to understand the pathological changes in abnormal tendons, provide exposure to the emerging treatment techniques, and provide suggested direction for future research.

  8. Achilles and Patellar Tendinopathy Loading Programmes

    DEFF Research Database (Denmark)

    Malliaras, Peter; Barton, Christian J; Reeves, Neil D

    2013-01-01

    . Eccentric-concentric progressing to eccentric (Silbernagel combined) and eccentric-concentric isotonic (heavy-slow resistance; HSR) loading have also been investigated. In order for clinicians to make informed decisions, they need to be aware of the loading options and comparative evidence. The mechanisms...... mechanism that was consistently associated with improved clinical outcomes in both Achilles and patellar tendon rehabilitation was improved neuromuscular performance (e.g. torque, work, endurance), and Silbernagel-combined (Achilles) HSR loading (patellar) had an equivalent or higher level of evidence than...... isolated eccentric loading. In the Achilles tendon, a majority of studies did not find an association between improved imaging (e.g. reduced anteroposterior diameter, proportion of tendons with Doppler signal) and clinical outcomes, including all high-quality studies. In contrast, HSR loading...

  9. CKS knee prosthesis: biomechanics and clinical results in 42 cases.

    Science.gov (United States)

    Martucci, E; Verni, E; Del Prete, G; Stulberg, S D

    1996-01-01

    From 1991 to 1993 a total of 42 CKS prostheses were implanted for the following reasons: osteoarthrosis (34 cases), rheumatoid arthritis (7 cases) tibial necrosis (1 case). At follow-up obtained after 17 to 41 months the results were: excellent or good: 41; the only poor result was probably related to excessive tension of the posterior cruciate ligament. 94% of the patients reported complete regression of pain, 85% was capable of going up and down stairs without support. Mean joint flexion was 105 degrees. Radiologically the anatomical axis of the knee had a mean valgus of anatomical axis of the knee had a mean valgus of 6 degrees. The prosthetic components were always cemented. The posterior cruciate ligament was removed in 7 knees, so that the prosthesis with "posterior stability" was used. The patella was never prosthetized. One patient complained of peri-patellar pain two months after surgery which then regressed completely.

  10. T2 mapping in patellar chondromalacia

    International Nuclear Information System (INIS)

    Ruiz Santiago, Fernando; Pozuelo Calvo, Rocío; Almansa López, Julio; Guzmán Álvarez, Luis; Castellano García, María del Mar

    2014-01-01

    Objective: To study the correlation between the T2 relaxation times of the patellar cartilage and morphological MRI findings of chondromalacia. Methods: This prospective study comprises 50 patients, 27 men and 23 women suffering of anterior knee pain (mean age: 29.7, SD 8.3 years; range: 16–45 years). MRI of 97 knees were performed in these patients at 1.5 T magnet including sagittal T1, coronal intermediate, axial intermediate fat sat and T2 mapping. Chondromalacia was assessed using a modified version of Noyes classification. The relaxation time, T2, was studied segmenting the full thickness of the patellar cartilage in 12 areas: 4 proximal (external facet–proximal–lateral (EPL), external facet–proximal–central (EPC), internal facet–proximal–central (IPC), internal facet–proximal–medial (IPM), 4 in the middle section (external facet–middle–lateral (EML), external facet–middle–central (EMC), internal facet–middle–central (IMC), internal facet–middle–medial (IMM) and 4 distal (external facet–distal–lateral (EDL), external facet–distal–central (EDC), internal facet–distal–central (IDC), internal facet–distal–medial (IDM). Results: T2 values showed a significant increase in mild chondromalacia regarding normal cartilage in most of the cartilage areas (p < 0.05), except in the internal distal facet (IDC and IDM), EPC, EDL, and IMM. Severe chondromalacia was characterized by a fall of T2 relaxation times with loss of statistical significant differences in comparison with normal cartilage, except in EMC and IMC, where similar values as mild chondromalacia were maintained (p < 0.05). Conclusions: Steepest increase in T2 values of patellar cartilage occurs in early stages of patellar cartilage degeneration. Progression of morphologic changes of chondromalacia to more severe degrees is associated to a new drop of T2 relaxation times approaching basal values in most of the areas of the patellar cartilage, except in the

  11. T2 mapping in patellar chondromalacia

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Santiago, Fernando, E-mail: ferusan12@gmail.com [Department of Radiology, Traumatology Hospital, University Hospital Virgen de las Nieves, Granada (Spain); Pozuelo Calvo, Rocío [Department of Rehabilitation and Physical therapy, Traumatology Hospital, University Hospital Virgen de las Nieves, Granada (Spain); Almansa López, Julio [Department of Physic, University Hospital Virgen de las Nieves, Granada (Spain); Guzmán Álvarez, Luis; Castellano García, María del Mar [Department of Radiology, Traumatology Hospital, University Hospital Virgen de las Nieves, Granada (Spain)

    2014-06-15

    Objective: To study the correlation between the T2 relaxation times of the patellar cartilage and morphological MRI findings of chondromalacia. Methods: This prospective study comprises 50 patients, 27 men and 23 women suffering of anterior knee pain (mean age: 29.7, SD 8.3 years; range: 16–45 years). MRI of 97 knees were performed in these patients at 1.5 T magnet including sagittal T1, coronal intermediate, axial intermediate fat sat and T2 mapping. Chondromalacia was assessed using a modified version of Noyes classification. The relaxation time, T2, was studied segmenting the full thickness of the patellar cartilage in 12 areas: 4 proximal (external facet–proximal–lateral (EPL), external facet–proximal–central (EPC), internal facet–proximal–central (IPC), internal facet–proximal–medial (IPM), 4 in the middle section (external facet–middle–lateral (EML), external facet–middle–central (EMC), internal facet–middle–central (IMC), internal facet–middle–medial (IMM) and 4 distal (external facet–distal–lateral (EDL), external facet–distal–central (EDC), internal facet–distal–central (IDC), internal facet–distal–medial (IDM). Results: T2 values showed a significant increase in mild chondromalacia regarding normal cartilage in most of the cartilage areas (p < 0.05), except in the internal distal facet (IDC and IDM), EPC, EDL, and IMM. Severe chondromalacia was characterized by a fall of T2 relaxation times with loss of statistical significant differences in comparison with normal cartilage, except in EMC and IMC, where similar values as mild chondromalacia were maintained (p < 0.05). Conclusions: Steepest increase in T2 values of patellar cartilage occurs in early stages of patellar cartilage degeneration. Progression of morphologic changes of chondromalacia to more severe degrees is associated to a new drop of T2 relaxation times approaching basal values in most of the areas of the patellar cartilage, except in the

  12. To Compare the Effect of Pre and Post Weight Bearing Anxiety, Depression in Conventional and Modular Prosthesis on Unilateral Transtibial Amputees

    Directory of Open Access Journals (Sweden)

    R. Raja

    2014-01-01

    Full Text Available Aims and Objectives: To compare the effect of anxiety and depression on unilateral trans tibial amputees those who are using conventional and modular patellar tendon bearing (PTB prosthesis with stump exercises. Material and Methods: A sample of 40 persons with below knee amputation who were trained to wear prosthesis were studied with an experimental comparative study design. Patients who were admitted at Kempegowda Institute of Medical Sciences and Research Centre, Bangalore, K. S. Hegde Medical Academy and Research Centre Mangalore, (N=150 who underwent unilateral transtibial, transfemoral and other amputations between August 2009 - December 2011. To find out peri and postoperative prosthetic fitting, anxiety and depression level of transtibial amputees who wear conventional and modular PTB prosthesis. 3 years of experimental comparative study reveals that the outcome measures of peri and post-operative anxiety and depression level while using conventional PTB prosthesis with stump exercises and modular PTB prosthesis with stump exercises on unilateral transtibial amputees. Results: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group patients anxiety and depression levels are reduced as compared to the unilateral transtibial amputees who were trained with conventional PTB prosthesis along with stump exercises. There is no significant difference seen in both the groups while giving stump exercises alone. Conclusion: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group, patient’s anxiety and depression levels are reduced drastically.

  13. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    International Nuclear Information System (INIS)

    Collins, Mark S.; Tiegs-Heiden, Christin A.; Stuart, Michael J.

    2014-01-01

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: 1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  14. Epidemiology of Patellar Tendinopathy in Elite Male Soccer Players

    NARCIS (Netherlands)

    Hägglund, Martin; Zwerver, Johannes; Ekstrand, Jan

    Background: Patellar tendinopathy is common among athletes in jumping sports and in sports with prolonged repetitive stress of the knee extensor apparatus. The epidemiology in soccer is not well described. Purpose: This study was undertaken to investigate and describe the epidemiology of patellar

  15. Patellar tendinopathy : Causes, consequences and the use of orthoses

    NARCIS (Netherlands)

    de Vries, Astrid Johanna

    2016-01-01

    Patellar tendinopathy (PT), also known as jumper’s knee, is a painful overuse injury of the patellar tendon. This injury is common in jumping athletes. There are numerous treatment options currently available for PT, yet none of them guarantee full recovery. As a result, many athletes have

  16. The effect of a patellar strap on knee joint proprioception in healthy participants and athletes with patellar tendinopathy

    NARCIS (Netherlands)

    de Vries, Astrid J.; van den Akker-Scheek, Inge; Diercks, Ron L.; Zwerver, Johannes; van der Worp, Henk

    Objectives: The primary aim of this study is to investigate the effect of the use of a patellar strap on knee joint proprioception in both healthy participants and in patients with patellar tendinopathy (PT). Secondary aims are to examine whether there is a difference in effectiveness of the use of

  17. Patellar Instability Management: A Survey of the International Patellofemoral Study Group.

    Science.gov (United States)

    Liu, Joseph N; Steinhaus, Michael E; Kalbian, Irene L; Post, William R; Green, Daniel W; Strickland, Sabrina M; Shubin Stein, Beth E

    2017-10-01

    Although patellofemoral instability is among the most prevalent knee disorders, the management of patients with this condition is complex and remains variable, given the lack of long-term, high-level clinical outcome studies to compare various operative and nonoperative modalities. To discover a consensus within treatment controversies in patellofemoral instability among experienced knee surgeons with a specific interest in the patellofemoral joint. Expert opinion; Level of evidence, 5. A 3-step modified Delphi technique was used to establish a consensus. A 34-question, case-based online survey regarding patellofemoral instability was distributed to all active members of the International Patellofemoral Study Group. Consensus statements were generated if at least 66% of the respondents agreed and then redistributed to the same panel. Modifications to the consensus statements were made based on the iterative feedback process until no discordance was encountered in the third stage. Eight consensus statements were achieved. Nonoperative management is the current standard of care for a first-time dislocation in the absence of an osteochondral fragment or loose body requiring excision (100% agreement). In patients with a first-time dislocation with an operative osteochondral fracture requiring excision or repair, patellar instability should be addressed concurrently (89% agreement). Recurrent instability should be treated surgically, with most surgeons favoring medial reconstruction (77%-86% agreement). While there is general agreement that bony procedures should be performed to correct underlying bony deformities, there is no consensus regarding the most appropriate type of procedure performed. Lateral release should not be performed in isolation for the treatment of patellar instability (89% agreement). Despite the consensus generated in this study, our current understanding remains limited by a lack of high-level evidence as well as the numerous complex variables

  18. T2 mapping in patellar chondromalacia.

    Science.gov (United States)

    Ruiz Santiago, Fernando; Pozuelo Calvo, Rocío; Almansa López, Julio; Guzmán Álvarez, Luis; Castellano García, María Del Mar

    2014-06-01

    To study the correlation between the T2 relaxation times of the patellar cartilage and morphological MRI findings of chondromalacia. This prospective study comprises 50 patients, 27 men and 23 women suffering of anterior knee pain (mean age: 29.7, SD 8.3 years; range: 16-45 years). MRI of 97 knees were performed in these patients at 1.5T magnet including sagittal T1, coronal intermediate, axial intermediate fat sat and T2 mapping. Chondromalacia was assessed using a modified version of Noyes classification. The relaxation time, T2, was studied segmenting the full thickness of the patellar cartilage in 12 areas: 4 proximal (external facet-proximal-lateral (EPL), external facet-proximal-central (EPC), internal facet-proximal-central (IPC), internal facet-proximal-medial (IPM), 4 in the middle section (external facet-middle-lateral (EML), external facet-middle-central (EMC), internal facet-middle-central (IMC), internal facet-middle-medial (IMM) and 4 distal (external facet-distal-lateral (EDL), external facet-distal-central (EDC), internal facet-distal-central (IDC), internal facet-distal-medial (IDM). T2 values showed a significant increase in mild chondromalacia regarding normal cartilage in most of the cartilage areas (pchondromalacia was characterized by a fall of T2 relaxation times with loss of statistical significant differences in comparison with normal cartilage, except in EMC and IMC, where similar values as mild chondromalacia were maintained (pchondromalacia to more severe degrees is associated to a new drop of T2 relaxation times approaching basal values in most of the areas of the patellar cartilage, except in the central area of the middle section, where T2 values remain increased. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Extracorporeal shockwave for chronic patellar tendinopathy.

    Science.gov (United States)

    Wang, Ching-Jen; Ko, Jih-Yang; Chan, Yi-Sheng; Weng, Lin-Hsiu; Hsu, Shan-Lin

    2007-06-01

    Chronic patellar tendinopathy is an overuse syndrome with pathologic changes similar to tendinopathies of the shoulder, elbow, and heel. Extracorporeal shockwave was shown effective in many tendinopathies. Extracorporeal shockwave therapy may be more effective than conservative treatment for chronic patellar tendinopathy. Randomized controlled clinical trial; Level of evidence, 2. This study consisted of 27 patients (30 knees) in the study group and 23 patients (24 knees) in the control group. In the study group, patients were treated with 1500 impulses of extracorporeal shockwave at 14 KV (equivalent to 0.18 mJ/mm(2) energy flux density) to the affected knee at a single session. Patients in the control group were treated with conservative treatments including nonsteroidal anti-inflammatory drugs, physiotherapy, exercise program, and the use of a knee strap. The evaluation parameters included pain score, Victorian Institute of Sports Assessment score, and ultrasonographic examination at 1, 3, 6, and 12 months and then once a year. At the 2- to 3-year follow-up, the overall results for the study group were 43% excellent, 47% good, 10% fair, and none poor. For the control group, the results were none excellent, 50% good, 25% fair, and 25% poor. The mean Victorian Institute of Sports Assessment scores were 42.57 +/- 10.22 and 39.25 +/- 10.85, respectively, before treatment (P = .129) and 92.0 +/- 10.17 and 41.04 +/- 10.96, respectively, after treatment (P Extracorporeal shockwave therapy appeared to be more effective and safer than traditional conservative treatments in the management of patients with chronic patellar tendinopathy.

  20. Dislocation: First Aid

    Science.gov (United States)

    ... or a collision during contact or high-speed sports. Dislocation usually involves the body's larger joints. In adults, the most common site of the injury is the shoulder. In children, it's the elbow. ...

  1. Broken or dislocated jaw

    Science.gov (United States)

    ... broken or dislocated jaw requires prompt medical attention. Emergency symptoms include difficulty breathing or heavy bleeding. ... safety equipment, such as a helmet when playing football, or using ... can prevent or minimize some injuries to the face or jaw.

  2. Bilateral patellar tuberculosis masquerading as infected infrapatellar bursitis.

    Science.gov (United States)

    Sreenivasan, Ravi; Haq, Rehan Ul

    2017-04-01

    A 30-year-old woman presented to our outpatient department with complaints of pain and swelling in bilateral infrapatellar regions and a discharging sinus in the right knee over the duration of one year. Radiographs showed lytic regions in bilateral patellae. Samples sent from material curetted from sinus yielded no organism but histopathology reported granulomatous inflammation. Following a fresh magnetic resonance imaging (MRI) scan that revealed the infrapatellar pad of fat communicating with the patellar lesions, an exploration and evacuation was done. Material sent revealed epithelioid cell granulomas with caseous necrosis consistent with tuberculosis (TB). The patient was put on first line anti-tubercular treatment (ATT) and has responded favourably with healing of sinus and patellar lesions. Bilateral infrapatellar bursitis is not rare. However patellar TB as a cause for OMIT is not a common diagnosis. A bilateral patellar involvement has not been reported in literature to the best of our knowledge.

  3. Patellar calcar: MRI appearance of a previously undescribed anatomical entity

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Mark S.; Tiegs-Heiden, Christin A. [Department of Radiology, Mayo Clinic, Rochester, Minnesota (United States); Stuart, Michael J. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota (United States)

    2014-02-15

    The femoral calcar is a constant anatomical structure within the proximal femur representing a condensation of bone trabeculae. It is our impression that a similar structure is present within the patella. The purpose of this retrospective study was to define the prevalence, appearance, location, and configuration of the patellar calcar on MRI examinations. One hundred consecutive unenhanced knee MRIs were retrospectively reviewed by two readers who were blinded to the clinical indication. The patellar calcar was defined as a dark signaling, linear or curvilinear structure subjacent to the patellar articular surface. If present, the patellar calcar was assigned to a ''well seen,'' ''moderately well seen,'' or ''faintly seen'' category. Location of the calcar within the patella, orientation, configuration, and thickness were recorded. Confounding variables, such as marrow edema, patellar chondromalacia, bipartite patella, or postoperative changes were also recorded. The patellar calcar was visualized in 81 out of 100 (81 %) MRIs. When detected, the calcar was well seen in 20 out of 81 (25 %), moderately well seen in 35 out of 81 (43 %), and faintly seen in 26 out of 81 (32 %). The anteroposterior width of the calcar measured at its thickest segment was: < 1 mm in 43 out of 81 (53 %), 1 mm in 28 out of 81 (35 %), and >1 mm in 10 out of 81 (12 %). The patellar calcar was seen in the majority of knee MRIs and had a consistent imaging appearance. The calcar may be obscured by degenerative arthrosis of the patella and rarely may mimic patellar stress fracture or osteochondritis dissecans. Radiologists and clinicians should be familiar with this normal anatomical structure. (orig.)

  4. Dislocation Dynamics During Plastic Deformation

    CERN Document Server

    Messerschmidt, Ulrich

    2010-01-01

    The book gives an overview of the dynamic behavior of dislocations and its relation to plastic deformation. It introduces the general properties of dislocations and treats the dislocation dynamics in some detail. Finally, examples are described of the processes in different classes of materials, i.e. semiconductors, ceramics, metals, intermetallic materials, and quasicrystals. The processes are illustrated by many electron micrographs of dislocations under stress and by video clips taken during in situ straining experiments in a high-voltage electron microscope showing moving dislocations. Thus, the users of the book also obtain an immediate impression and understanding of dislocation dynamics.

  5. Results of Lateral Retinacular Release Plus Circumpatellar Electrocautery in Total Knee Arthroplasty without Patellar Resurfacing.

    Science.gov (United States)

    Wang, Yong; Sun, Jun-Ying; Zha, Guo-Chun

    2017-03-01

    Anterior knee pain (AKP) is integral to the overall success of total knee arthroplasty (TKA) without patellar resurfacing. Numerous studies have evaluated various factors that may contribute to AKP, including patellofemoral design, surgical technique, characteristics of the patient, and degree of chondromalacia. This study aims to explore whether patients who received lateral retinacular release (LRR) plus circumpatellar electrocautery (CE) in TKA attain a low incidence of AKP and whether the LRR plus CE increases postoperative complications. Between February 2001 and February 2009, all patients undergoing TKA without patellar resurfacing and LRR plus CE were evaluated. In total, 286 TKAs in 259 (88.7%) patients were available for assessment, with a mean of 9.3 ± 2.5 years (range: 6-14 years) after the index TKA. The patients were evaluated with a VAS and the Kujala patellofemoral score (KPS) for AKP and the Knee Society's clinical scoring system (KSS) for the clinical function. Satisfaction and LRR-related complications were also assessed. The mean KPS and KSS improved from 45.2 ± 12.9 and 75.4 ± 26.8 points preoperatively to 82.8 ± 10.0 and 151.6 ± 17.3 points at the final follow-up ( p  < 0.001), respectively. Subjectively, 5.6% (16 of 286) of patients suffered from AKP and 88.1% (252 of 286) were satisfied or very satisfied. Postoperative complications occurred in 15 (5.2%) patients, but these complications were mild and did not require reoperation. None of patients exhibited aseptic and septic prosthesis loosening and required revision surgery in the final follow-up. LRR plus CE appears to be a reasonable option in TKA without patellar resurfacing. It may achieve adequate mid-term results, with a low incidence of AKP and postoperative complications.The level of evidence of the study is therapeutic level IV. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  6. Reconstruction of medial patellofemoral ligament using quadriceps tendon combined with reconstruction of medial patellotibial ligament using patellar tendon: initial experience

    Directory of Open Access Journals (Sweden)

    Betina Bremer Hinckel

    2016-02-01

    Full Text Available ABSTRACT OBJECTIVE: To describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series. METHOD: The proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC-IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM, apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from 0 to 10 and whether they would be prepared to go through this operation again. RESULTS: Seven knees were operated, in seven patients, with a mean follow-up of 5.46 months (±2.07. Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound. CONCLUSION: Reconstruction of the

  7. The reverse shoulder prosthesis: a review of imaging features and complications

    Energy Technology Data Exchange (ETDEWEB)

    McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi [Johns Hopkins University, Department of Orthopedic Surgery, Lutherville, MD (United States); Keyurapan, Ekavit [Mahidol University, Department of Orthopaedic Surgery, Bangkok (Thailand); Fishman, Elliot K.; Fayad, Laura M. [Johns Hopkins Medical Institutions, Johns Hopkins University, Department of Radiology and Radiological Sciences, Baltimore, MD (United States)

    2006-07-15

    The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

  8. The reverse shoulder prosthesis: a review of imaging features and complications

    International Nuclear Information System (INIS)

    McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi; Keyurapan, Ekavit; Fishman, Elliot K.; Fayad, Laura M.

    2006-01-01

    The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

  9. Dislocation climb models from atomistic scheme to dislocation dynamics

    OpenAIRE

    Niu, Xiaohua; Luo, Tao; Lu, Jianfeng; Xiang, Yang

    2016-01-01

    We develop a mesoscopic dislocation dynamics model for vacancy-assisted dislocation climb by upscalings from a stochastic model on the atomistic scale. Our models incorporate microscopic mechanisms of (i) bulk diffusion of vacancies, (ii) vacancy exchange dynamics between bulk and dislocation core, (iii) vacancy pipe diffusion along the dislocation core, and (iv) vacancy attachment-detachment kinetics at jogs leading to the motion of jogs. Our mesoscopic model consists of the vacancy bulk dif...

  10. Dislocation of jaws

    International Nuclear Information System (INIS)

    Katzberg, R.W.; Hayakawa, K.; Anderson, Q.N.; Manzione, J.V.; Helms, C.A.; Tallents, R.

    1984-01-01

    Pluri-directional tomographic and arthrotomographic findings are described in six patients with dislocation of the jaw severe enough to require medical assistance. A grooved defect along the posterior aspect of the condylar head was noted in two of the six patients. The arthrotomographic findings that were obtained in one patient that was dislocated at the time of the arthrogram did not suggest a meniscocondyle incoordination as a mechanism. However, arthrotomographic findings in the six reported cases suggest that significant intra-articular soft tissue damage may result. (orig.)

  11. Prosthesis-patient mismatch

    Directory of Open Access Journals (Sweden)

    Philippe Pibarot

    2011-04-01

    Full Text Available Prosthesis-patient mismatch (PPM is present when the effective orifice area of the inserted prosthetic valve is too small in relation to body size. Its main hemodynamic consequence is to generate higher than expected gradients through normally functioning prosthetic valves. The purpose of this review is to present an update on the present state of knowledge with regards to diagnosis, prognosis and prevention of PPM. PPM is a frequent occurrence (20%–70% of aortic valve replacements that has been shown to be associated with worse hemodynamics, less regression of left ventricular hypertrophy, more cardiac events, and lower survival. Moreover, as opposed to most other risk factors, PPM can largely be prevented by using a prospective strategy at the time of operation.

  12. Bioelectronic retinal prosthesis

    Science.gov (United States)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  13. Dislocated Worker Project.

    Science.gov (United States)

    1988

    Due to the severe economic decline in the automobile manufacturing industry in southeastern Michigan, a Dislocated Workers Program has been developed through the partnership of the Flint Area Chamber of Commerce, three community colleges, the National Center for Research in Vocational Education, the Michigan State Department of Education, the…

  14. Smectic meniscus and dislocations

    International Nuclear Information System (INIS)

    Geminard, J.C.; Oswald, P.; Holyst, R.

    1998-01-01

    In ordinary liquids the size of a meniscus and its shape is set by a competition between surface tension and gravity. The thermodynamical process of its creation can be reversible. On the contrary, in smectic liquid crystals the formation of the meniscus is always an irreversible thermodynamic process since it involves the creation of dislocations (therefore it involves friction). Also the meniscus is usually small in experiments with smectics in comparison to the capillary length and therefore the gravity does not play any role in determining the meniscus shape. Here we discuss the relation between dislocations and meniscus in smectics. The theoretical predictions are supported by a recent experiment performed on freely suspended films of smectic liquid crystals. In this experiment the measurement of the meniscus radius of curvature gives the pressure difference, Δp, according to the Laplace law. From the measurements of the growth dynamics of a dislocation loop (governed by Δp) we find the line tension (∼8 x 10 -8 dyn) and the mobility of an elementary edge dislocation (∼4 x 10 - 7 cm 2 s/g). (author)

  15. Dislocated Shoulder: Symptoms and Causes

    Science.gov (United States)

    ... caused by: Sports injuries. Shoulder dislocation is a common injury in contact sports, such as football and hockey, and in sports that may involve falls, such as downhill skiing, gymnastics and volleyball. ... is a common source of dislocation. Falls. You may dislocate your ...

  16. Analysis of failed surgery for patellar instability in children with open growth plates.

    Science.gov (United States)

    Nelitz, Manfred; Theile, Michael; Dornacher, Daniel; Wölfle, Julia; Reichel, Heiko; Lippacher, Sabine

    2012-05-01

    Many surgical procedures have been proposed to treat recurrent patellar dislocation in children. In recent years, a more tailored approach considering the underlying pathology has been advocated. The aim of the study was to analyze a group of patients with recurrent patellofemoral instability after unsuccessful operative stabilization (Roux-Goldthwait procedure, lateral release, medial reefing or in combination) in childhood and adolescence. A total of 37 children and adolescents with recurrent patellofemoral instability despite previous surgery were analyzed retrospectively. Radiographic examination included AP and lateral views to assess patella alta and limb alignment. MRI was performed to evaluate trochlear dysplasia and tibial tubercle-trochlear groove (TTTG) distance. As a control group, 23 age- and sex-matched adolescents that were treated with a favorable outcome after medial reefing alone or combined with a Roux-Goldthwait procedure were analyzed. Severe trochlear dysplasia (type B-D according to Dejour) as detected on MRI scans was found significantly more often in the study group (89%) than in the control group (21%). No statistical difference of patellar height ratio (Insall-Salvati index) and TTTG distance between the two groups could be found. Of the measured parameters, only the incidence of trochlear dysplasia was increased. Trochlear dysplasia therefore seems to be a major risk factor for failure of operative stabilization of recurrent patellofemoral instability in children and adolescents. The results in children are in consensus with the literature in adults that a more tailored operative therapy including reconstruction of the MPFL and trochleaplasty has to be considered. Retrospective study, Level III.

  17. Decline eccentric squats increases patellar tendon loading compared to standard eccentric squats

    DEFF Research Database (Denmark)

    Kongsgaard, M; Aagaard, P; Roikjaer, S

    2006-01-01

    Recent studies have shown excellent clinical results using eccentric squat training on a 25 degrees decline board to treat patellar tendinopathy. It remains unknown why therapeutic management of patellar tendinopathy using decline eccentric squats offer superior clinical efficacy compared...

  18. Does the adolescent patellar tendon respond to 5 days of cumulative load during a volleyball tournament?

    NARCIS (Netherlands)

    van Ark, M.; Docking, S.I.; van den Akker-Scheek, I.; Rudavsky, A.; Rio, E.; Zwerver, J.; Cook, J.L.

    Patellar tendinopathy (jumper's knee) has a high prevalence in jumping athletes. Excessive load on the patellar tendon through high volumes of training and competition is an important risk factor. Structural changes in the tendon are related to a higher risk of developing patellar tendinopathy. The

  19. Differences in tendon properties in elite badminton players with or without patellar tendinopathy

    DEFF Research Database (Denmark)

    Couppé, Christian; Kongsgaard, M; Aagaard, Per

    2013-01-01

    The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players...

  20. Tailoring Superconductivity with Quantum Dislocations.

    Science.gov (United States)

    Li, Mingda; Song, Qichen; Liu, Te-Huan; Meroueh, Laureen; Mahan, Gerald D; Dresselhaus, Mildred S; Chen, Gang

    2017-08-09

    Despite the established knowledge that crystal dislocations can affect a material's superconducting properties, the exact mechanism of the electron-dislocation interaction in a dislocated superconductor has long been missing. Being a type of defect, dislocations are expected to decrease a material's superconducting transition temperature (T c ) by breaking the coherence. Yet experimentally, even in isotropic type I superconductors, dislocations can either decrease, increase, or have little influence on T c . These experimental findings have yet to be understood. Although the anisotropic pairing in dirty superconductors has explained impurity-induced T c reduction, no quantitative agreement has been reached in the case a dislocation given its complexity. In this study, by generalizing the one-dimensional quantized dislocation field to three dimensions, we reveal that there are indeed two distinct types of electron-dislocation interactions. Besides the usual electron-dislocation potential scattering, there is another interaction driving an effective attraction between electrons that is caused by dislons, which are quantized modes of a dislocation. The role of dislocations to superconductivity is thus clarified as the competition between the classical and quantum effects, showing excellent agreement with existing experimental data. In particular, the existence of both classical and quantum effects provides a plausible explanation for the illusive origin of dislocation-induced superconductivity in semiconducting PbS/PbTe superlattice nanostructures. A quantitative criterion has been derived, in which a dislocated superconductor with low elastic moduli and small electron effective mass and in a confined environment is inclined to enhance T c . This provides a new pathway for engineering a material's superconducting properties by using dislocations as an additional degree of freedom.

  1. Patellar denervation with electrocautery in total knee arthroplasty without patellar resurfacing: a meta-analysis.

    Science.gov (United States)

    Cheng, Tao; Zhu, Chen; Guo, Yongyuan; Shi, Sifeng; Chen, Desheng; Zhang, Xianlong

    2014-11-01

    The impact of patellar denervation with electrocautery in total knee arthroplasty (TKA) on post-operative outcomes has been under debate. This study aims to conduct a meta-analysis and systematic review to compare the benefits and risks of circumpatellar electrocautery with those of non-electrocautery in primary TKAs. Comparative and randomized clinical studies were identified by conducting an electronic search of articles dated up to September 2012 in PubMed, EMBASE, Scopus, and the Cochrane databases. Six studies that focus on a total of 849 knees were analysed. A random-effects model was conducted using the inverse-variance method for continuous variables and the Mantel-Haenszel method for dichotomous variables. There was no significant difference in the incidence of anterior knee pain between the electrocautery and non-electrocautery groups. In term of patellar score and Knee Society Score, circumpatellar electrocautery improved clinical outcomes compared with non-electrocautery in TKAs. The statistical differences were in favour of the electrocautery group but have minimal clinical significance. In addition, the overall complications indicate no statistical significance between the two groups. This study shows no strong evidence either for or against electrocautery compared with non-electrocautery in TKAs. Therapeutic study (systematic review and meta-analysis), Level III.

  2. Neglected isolated scaphoid dislocation

    Directory of Open Access Journals (Sweden)

    Jong-Ryoon Baek

    2016-01-01

    Full Text Available The authors present a case of isolated scaphoid dislocation in a 40-year-old male that was undiagnosed for 2 months. The patient was treated by open reduction, Kirschner wire fixation, interosseous ligament repair using a suture anchor and Blatt's dorsal capsulodesis. At 6 years followup, his radiographs of wrist showed a normal carpal alignment with a scapholunate gap of 3 mm and no evidence of avascular necrosis (AVN of the scaphoid.

  3. Dechanneling by dislocation loops

    International Nuclear Information System (INIS)

    Chalant, Gerard.

    1976-09-01

    Ion implantation always induces the creation of dislocation loops. When the damage profile is determined by a backscattering technique, the dechanneling by these loops is implicitely at the origin of these measurements. The dechanneling of alpha particles by dislocation loops produced by the coalescence of quenched-in vacancies in aluminium is studied. The dechanneling and the concentration of loops were determined simultaneously. The dechanneling width around dislocation was found equal to lambda=6A, both for perfect and imperfect loops having a mean diameter d=250A. In the latter case, a dechanneling probability chi=0.34 was determined for the stacking fault, in good agreement with previous determination in gold. A general formula is proposed which takes into account the variation of lambda with the curvature (or the diameter d) of the loops. Finally, by a series of isothermal anneals, the self-diffusion energy ΔH of aluminium was measured. The value obtained ΔH=1.32+-0.10eV is in good agreement with the values obtained by other methods [fr

  4. Dislocation of total hip replacement in patients with fractures of the femoral neck

    OpenAIRE

    Enocson, Anders; Hedbeck, Carl-Johan; Tidermark, Jan; Pettersson, Hans; Ponzer, Sari; Lapidus, Lasse J

    2009-01-01

    Background Total hip replacement is increasingly used in active, relatively healthy elderly patients with fractures of the femoral neck. Dislocation of the prosthesis is a severe complication, and there is still controversy regarding the optimal surgical approach and its influence on stability. We analyzed factors influencing the stability of the total hip replacement, paying special attention to the surgical approach. Patients and methods We included 713 consecutive hips in a series of 698 p...

  5. The effect of a patellar strap on knee joint proprioception in healthy participants and athletes with patellar tendinopathy.

    Science.gov (United States)

    de Vries, Astrid J; van den Akker-Scheek, Inge; Diercks, Ron L; Zwerver, Johannes; van der Worp, Henk

    2016-04-01

    The primary aim of this study is to investigate the effect of the use of a patellar strap on knee joint proprioception in both healthy participants and in patients with patellar tendinopathy (PT). Secondary aims are to examine whether there is a difference in effectiveness of the use of a patellar strap between participants with low and high proprioceptive acuity and if possible predictors of effectiveness can be determined. Case-control. The threshold to detect passive motion with and without a patellar strap was assessed in 22 healthy participants and 21 unilateral PT patients. The results from the mixed model analysis show that in both groups of participants a small but statistically significant improvement in proprioception was found, primarily in those who had low proprioceptive acuity. A notable finding was that in the symptomatic leg of the PT group no improvement in proprioception by wearing a strap could be determined. Male gender and having fewer symptoms were possible predictors of effectiveness in PT patients. As proprioception plays a role in optimising movements and reducing load to joint-related structures like tendons and ligaments, it is considered an important protection mechanism. Although the improvements in proprioception as a result of wearing the strap are small, it might be that the use of a patellar strap can potentially play a role in injury prevention since poor proprioception can be a risk factor for (re)-injury. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. Magnetic resonance imaging of bilateral lateral congenital dislocations of unossified patellae

    International Nuclear Information System (INIS)

    Calisir, Cuneyt; Yilmaz, Oguzhan; Inan, Ulukan

    2006-01-01

    We describe our experience using magnetic resonance imaging (MRI) to evaluate the unossified dislocated cartilaginous patella in a 6-year-old male patient with restricted extension and flexion deformity of both knees. MRI is used widely in the visualization of cartilage since it can show cartilage directly. In addition, FS FLASH 3D sequence has recently been accepted as a suitable sequence in the evaluation of hyaline cartilage. MRI makes it possible to evaluate ligamentous, tendinous, muscular, and cartilaginous structures as well as the abnormalities related to them. We applied this technique in our case and found it very effective in locating the unossified dislocated cartilaginous patella. We also observed structural changes such as bilateral lateral displacement of short quadriceps tendon inserting into diminutive patella, insertion of bilateral patellar tendons into anterolateral tibia, and a stretching of the medial collateral ligament associated with valgus stress. (orig.)

  7. Magnetic resonance imaging of bilateral lateral congenital dislocations of unossified patellae

    Energy Technology Data Exchange (ETDEWEB)

    Calisir, Cuneyt; Yilmaz, Oguzhan [Osmangazi University, Medical Faculty, Department of Radiology, Eskisehir (Turkey); Inan, Ulukan [Osmangazi University, Medical Faculty, Department of Orthopaedic and Trauma Surgery, Eskisehir (Turkey)

    2006-06-15

    We describe our experience using magnetic resonance imaging (MRI) to evaluate the unossified dislocated cartilaginous patella in a 6-year-old male patient with restricted extension and flexion deformity of both knees. MRI is used widely in the visualization of cartilage since it can show cartilage directly. In addition, FS FLASH 3D sequence has recently been accepted as a suitable sequence in the evaluation of hyaline cartilage. MRI makes it possible to evaluate ligamentous, tendinous, muscular, and cartilaginous structures as well as the abnormalities related to them. We applied this technique in our case and found it very effective in locating the unossified dislocated cartilaginous patella. We also observed structural changes such as bilateral lateral displacement of short quadriceps tendon inserting into diminutive patella, insertion of bilateral patellar tendons into anterolateral tibia, and a stretching of the medial collateral ligament associated with valgus stress. (orig.)

  8. A 5-year Evaluation and Results of Treatment of Chronic Llocked Dislocations of the Shoulder Joint

    Directory of Open Access Journals (Sweden)

    Syawash Mirsaid Ghazi

    2008-11-01

    Full Text Available Background:Chronic neglected dislocation of the shoulder joint can be defined as a neglected dislocation for more than a 3 week period.However, it has been shown that the negligence could range from a 24 hour period to 6 months1. Depending on age,signs, symptoms,etiology and types of dislocation, conservative treatment or surgical intervention could be considered.Methods: In this study, 16 patients (13 were male and 3 were female were treated with chronic shoulder dislocations, 3 of which had bilateral dislocations. The age of this group ranged from 13-65 years with a mean age of 34 years. These patients were treated by closed or open reduction, either anterior, posterior or both approaches. Of 19 dislocations, 6 were anterior unilateral, 7 posterior unilateral, 1 anterior bilateral and 2 posterior bilateral dislocations. The mean period between dislocations and treatments was 3 months (from 4 weeks to 11 months,And the mean follow up period was 40 months (from 21 months to 5 years.Results: This study has shown that treatment varies according to pathology. In  this study the mean size of head defects was 35% and the extent of severity determined the approach. Findings at the last follow up were assessed according to Rowe and Zarins score and of the 19 shoulders assessed, 9 showed good and 10 showed excellent results. There was no recurrence of the dislocation in any patient.Conclusion:In some selected instances, open reduction of a chronic locked neglected shoulder dislocation of a 6 months period or more in young patients is recommended.This method is, however, contraindicated in elderly patients; in such cases a shoulder prosthesis is indicated.  

  9. Inferior patellar pole fragmentation in children: just a normal variant?

    Energy Technology Data Exchange (ETDEWEB)

    Kan, J.H.; Vogelius, Esben S.; Orth, Robert C.; Guillerman, R.P.; Jadhav, Siddharth P. [Texas Children' s Hospital, E.B. Singleton Pediatric Radiology, Houston, TX (United States)

    2015-06-15

    Fragmentary ossification of the inferior patella is often dismissed as a normal variant in children younger than 10 years of age. The purpose of this study was to determine whether fragmentary inferior patellar pole ossification is a normal variant or is associated with symptoms or signs of pathology using MRI and clinical exam findings as reference. A retrospective review was performed on 150 patients ages 5-10 years who underwent 164 knee radiography and MRI exams (45.1% male, mean age: 7.8 years). The presence or absence of inferior patellar pole fragmentation on radiography was correlated with the presence or absence of edema-like signal on MR images. Clinical notes were reviewed for the presence of symptoms or signs referable to the inferior patellar pole. These data were compared with a 1:1 age- and sex-matched control group without inferior pole fragmentation. Statistical analysis was performed using two-tailed t-tests. Forty of 164 (24.4%) knee radiographs showed fragmentary ossification of the inferior patella. Of these 40 knees, 62.5% (25/40) had edema-like signal of the inferior patellar bone marrow compared with 7.5% (3/40) of controls (P = 0.035). Patients with fragmentary ossification at the inferior patella had a significantly higher incidence of documented focal inferior patellar pain compared with controls (20% vs. 2.5%, P = 0.015). Inferior patellar pole fragmentation in children 5 to 10 years of age may be associated with localized symptoms and bone marrow edema-like signal and should not be routinely dismissed as a normal variant of ossification. (orig.)

  10. Patellar SPECT and planar imaging in orthopedic patients with knee pain

    International Nuclear Information System (INIS)

    Dehdashti, F.; Collier, B.D.; Johnson, R.P.; Isitman, A.T.; Hellman, R.S.; Carrera, G.F.; Krasnow, A.Z.

    1987-01-01

    Eighty-five painful knees in 56 patients were independently evaluated clinically, radiographically, and scintigraphically. All patients had an established final diagnosis of osteoarthritis or other predisposing conditions. Results of patellar bone scintigraphy were abnormal in 66 of 85 knees; there were ten isolated findings and 12 cases of medial, nine of lateral, and 35 of triple compartment involvement. Four-quadrant patellar analysis identified nine instances of isolated lateal patellar facet syndrome. Single-photon emission CT was of significant value in localizing patellar abnormalities. Radiographic evaluation disclosed osteoarthritis in 27 of 66 scintigraphically abnormal knees. Patellar bone scintigraphy is more valuable than radiography for evaluating adult orthopedic patients with knee pain

  11. Permanent Quadriplegia Following Replacement of Voice Prosthesis.

    Science.gov (United States)

    Ozturk, Kayhan; Erdur, Omer; Kibar, Ertugrul

    2016-11-01

    The authors presented a patient with quadriplegia caused by cervical spine abscess following voice prosthesis replacement. The authors present the first reported permanent quadriplegia patient caused by voice prosthesis replacement. The authors wanted to emphasize that life-threatening complications may be faced during the replacement of voice prosthesis. Care should be taken during the replacement of voice prosthesis and if some problems have been faced during the procedure patients must be followed closely.

  12. Signs of patellar chondromalacia on sagittal T2-weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    De Smet, A.A.; Monu, J.U.; Fisher, D.R.; Keene, J.S.; Graf, B.K.

    1992-01-01

    We incidentally noted distinctive high signal defects or fissures in the patellar articular cartilage on sagittal T2-weighted magnetic resonance (MR) images in 4 patients. At subsequent arthroscopy all 4 patients were found to have patellar chondromalacia. To determine the reliabilty of these signs, we retrospectively evaluated, in a blinded manner, sagittal T2-weighted MR images of the knee in 75 patients who were undergoing arthroscopic assessment of their patellar articular cartilage. We indentified high signal defects of fissures in the patellar cartilage of 5 patients. Patellar chondromalacia was noted at arthroscopy in all 5 patients. Arthroscopy demonstrated patellar chondromalacia in an additional 21 patients with normal MR images. We conclude that high signal defects or fissures on sagittal T2-weighted images are usefull signs of patellar chondromalacia. This single imaging sequence will, however, detect only a small number of the cartilage lesions that may be present. (orig.)

  13. Signs of patellar chondromalacia on sagittal T2-weighted magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    De Smet, A.A.; Monu, J.U.; Fisher, D.R. (Univ. of Wisconsin Hospital and Clinics, Dept. of Radiology, Madison, WI (United States)); Keene, J.S.; Graf, B.K. (Univ. of Wisconsin Hospital and Clinics, Div. of Orthopedic Surgery, Madison, WI (United States))

    1992-02-01

    We incidentally noted distinctive high signal defects or fissures in the patellar articular cartilage on sagittal T2-weighted magnetic resonance (MR) images in 4 patients. At subsequent arthroscopy all 4 patients were found to have patellar chondromalacia. To determine the reliabilty of these signs, we retrospectively evaluated, in a blinded manner, sagittal T2-weighted MR images of the knee in 75 patients who were undergoing arthroscopic assessment of their patellar articular cartilage. We indentified high signal defects of fissures in the patellar cartilage of 5 patients. Patellar chondromalacia was noted at arthroscopy in all 5 patients. Arthroscopy demonstrated patellar chondromalacia in an additional 21 patients with normal MR images. We conclude that high signal defects or fissures on sagittal T2-weighted images are usefull signs of patellar chondromalacia. This single imaging sequence will, however, detect only a small number of the cartilage lesions that may be present. (orig.).

  14. Effects of Patellar Taping on the Patella Position in Presence of Quadriceps Contraction in 20-40 Year-Old Women With Patellofemoral Pain Syndrome Using MRI

    Directory of Open Access Journals (Sweden)

    Mahboobeh Banejad

    2016-06-01

    Discussion: Kinesio taping plus quadriceps contraction reduced the PFCA and LPFA. Patellar taping is effective in the correction of the patellar position in contracted quadriceps. Therefore, both neuromuscular and mechanical effects of patellar taping affect the patellar position over a long period. The combination of patellar taping and exercise reduced pain and improved activity faster than either of the treatment alone.

  15. Sex Variation in Patellar Tendon Kinetics During Running

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2015-06-01

    Full Text Available Purpose. The aim of the current investigation was to determine whether female recreational runners exhibit distinct patellar tendon loading patterns in relation to their male counterparts. Methods. Twelve male (age 26.55 ± 4.11 years, height 1.78 ± 0.11 m, mass 77.11 ± 5.06 kg and twelve female (age 26.67 ± 5.34 years, height 1.67 ± 0.12 m, mass 63.28 ± 9.75 kg runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system which operated at 250 Hz. Patellar tendon loads were examined using a predictive algorithm. Sex differences in limb, knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that patellar tendon force (male = 6.49 ± 2.28, female = 7.03 ± 1.35 and patelllar tendon loading rate (male = 92.41 ± 32.51, female = 111.05 ± 48.58 were significantly higher in female runners. Conclusions. Excessive tendon loading in female runners indicates that female runners may be at increased risk of patellar tendon pathologies.

  16. Bone growth into a revised porous-coated patellar implant

    DEFF Research Database (Denmark)

    Jensen, L N; Lund, B; Gotfredsen, K

    1990-01-01

    A noncemented and clinically stable porous-coated patellar component (PCA) was removed from a patient after 11 months because of infection. It was sectioned and examined histologically in undecalcified, thin-ground sections. The bone ingrowth into the porous space was measured at eight levels. Ea...

  17. Relationship between landing strategy and patellar tendinopathy in volleyball

    NARCIS (Netherlands)

    Bisseling, Rob W.; Hof, At L.; Bredeweg, Steef W.; Zwerver, Johannes; Mulder, Theo

    Objective: The aetiology of patellar tendinopathy ( jumper's knee) remains unclear. To see whether landing strategy might be a risk factor for the development of this injury, this study examined whether landing dynamics from drop jumps differed among healthy volleyball players ( CON) and volleyball

  18. Foot Posture and Patellar Tendon Pain Among Adult Volleyball Players

    NARCIS (Netherlands)

    de Groot, Reinier; Malliaras, Peter; Munteanu, Shannon; Payne, Craig; Morrissey, Dylan; Maffulli, Nicola

    Objective: We hypothesized that individuals with a normal foot posture would be less likely to experience patellar tendon pain and pathology than those with a pronated or supinated foot. Design: Observational study. Setting: Field-based study among competing athletes. Participants: Volleyball

  19. Comparative diagnostic imaging of a partial patellar ligament tear in ...

    African Journals Online (AJOL)

    Ibrahim Eldaghayes

    2018-04-27

    Apr 27, 2018 ... of the patellar or tibial insertion, and soft tissue opacity at the cranial aspect of the joint. ... the exclusion of microfracture and distal PL avulsion, but did not add information ..... angles and under stress (Hodgson et al., 2012).

  20. Foot posture and patellar tendon pain among adult volleyball players.

    NARCIS (Netherlands)

    Groot, R. de; Malliaras, P.; Munteanu, S.; Payne, C.; Morrissey, D.; Maffulli, N.

    2012-01-01

    OBJECTIVE: We hypothesized that individuals with a normal foot posture would be less likely to experience patellar tendon pain and pathology than those with a pronated or supinated foot. DESIGN: Observational study. SETTING: Field-based study among competing athletes. PARTICIPANTS: Volleyball

  1. Chondromalacia induced by patellar subluxation in the rabbit

    DEFF Research Database (Denmark)

    Møller, B.N.; Møller-Larsen, F.; Frich, Lars Henrik

    1989-01-01

    A unilateral patellar malalignment was induced in 20 young and 20 mature rabbits by lateral displacement of the tibial tuberosity, the other knee serving as osteotomized in situ control. At 6 weeks, all the knees appeared macroscopically normal, but histologically definite cartilage degeneration ...... produces changes resembling chondromalacia patellae and early arthrotic changes suggesting the importance of malalignment in the development of patellofemoral cartilage degeneration....

  2. Lateral patellar luxation in nine small breed dogs | Dona | Open ...

    African Journals Online (AJOL)

    The objective of this paper was to describe the clinical features, the management and the outcome of nine small breed dogs affected with lateral patella luxation referred during the period between January 2010 and December 2014. Patellar luxations were classified according to: breed, age, sex, weight, and grade of ...

  3. Magnetically retained silicone facial prosthesis

    African Journals Online (AJOL)

    2013-06-09

    Jun 9, 2013 ... Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention.

  4. Elektra prosthesis for trapeziometacarpal osteoarthritis

    DEFF Research Database (Denmark)

    Klahn, A; Nygaard, Mads; Gvozdenovic, R

    2012-01-01

    We present a prospective follow-up of 39 Elektra prostheses in 37 patients (32 women and five men), with a mean age of 56.5 (range 46-71) years; 34 patients had osteoarthritis and three had rheumatoid arthritis. Patients were followed using clinical examination, including measurement of pain...... be the key problem in treating trapeziometacarpal osteoarthritis using a total prosthesis....

  5. Patellar tendon load in different types of eccentric squats.

    Science.gov (United States)

    Frohm, A; Halvorsen, K; Thorstensson, A

    2007-07-01

    Differences in mechanical loading of the patellar tendon have been suggested as a reason for varying effects in rehabilitation of patellar tendinopathy using different eccentric squat exercises and devices. The aim was to characterize the magnitude and pattern of mechanical load at the knee and on the patellar tendon during four types of eccentric squat. Subjects performed squats with a submaximal free weight and with maximal effort in a device for eccentric overloading (Bromsman), on a decline board and horizontal surface. Kinematics was recorded with a motion-capture system, reaction forces with force plates, and electromyography from three leg muscles with surface electrodes. Inverse dynamics was used to calculate knee joint kinetics. Eccentric work, mean and peak patellar tendon force, and angle at peak force were greater (25-30%) for squats on decline board compared to horizontal surface with free weight, but not in Bromsman. Higher knee load forces (60-80%), but not work, were observed with Bromsman than free weight. Angular excursions at the knee and ankle were larger with decline board, particularly with free weight, and smaller in Bromsman than with free weight. Mean electromyography was greater on a decline board for gastrocnemius (13%) and vastus medialis (6%) with free weight, but in Bromsman only for gastrocnemius (7%). The results demonstrated clear differences in the biomechanical loading on the knee during different squat exercises. Quantification of such differences provides information that could be used to explain differences in rehabilitation effects as well as in designing more optimal rehabilitation exercises for patellar tendinopathy.

  6. Nature of Dislocations in Silicon

    DEFF Research Database (Denmark)

    Hansen, Lars Bruno; Stokbro, Kurt; Lundqvist, Bengt

    1995-01-01

    Interaction between two partial 90 degrees edge dislocations is studied with atomic-scale simulations using the effective-medium tight-binding method. A large separation between the two dislocations (up to 30 Angstrom), comparable to experimental values, is achieved with a solution of the tight-b...

  7. Traumatic hip dislocations in children

    International Nuclear Information System (INIS)

    Minhas, M.S.

    2010-01-01

    Objectives: To evaluate clinical features, treatment and relationship to the time period between dislocation, reduction and early complications of traumatic dislocation of hip in children. Methods: Case series conducted at Jinnah Post Graduate Medical Centre Karachi from July 2005 to August 2009. Children with traumatic hip dislocation up to fifteen years of age who presented in last four years were included in this study. Their clinical information, etiology, associated injuries, duration, method of reduction and early complications are evaluated through emergency room proforma and indoor record. Follow up of patient was updated in outpatient department. Results: We had eight patients, six boys and two girls. Youngest 2.4 years and eldest was 12 years with mean age of 6.2 +- 3.8 years. All presented with posterior hip dislocation. Etiology was road traffic accident in two and history of fall in remaining six patients. Average duration of time between dislocation and reduction was 19 hours range 3-72 hours. Dislocated hips were reduced under General Anaesthesia in two patients and under sedation analgesia in six patients. No complications were noted in eight cases with mean 18.75 +- 13.23 months follows up. Conclusion: Traumatic hip dislocation in children is not rare. Slight trauma causes dislocation in younger age and immediate closed reduction and Immobilization reduces complications. (author

  8. Effect of a patellar strap on the joint position sense of the symptomatic knee in athletes with patellar tendinopathy

    NARCIS (Netherlands)

    de Vries, Astrid J.; van den Akker-Scheek, Inge; Haak, Svenja L.; Diercks, Ron L.; van der Worp, Henk; Zwerver, Johannes

    2017-01-01

    Objectives: The primary aim of this study was to investigate the effect of a patellar strap on the proprioception of the symptomatic leg in PT. Secondary aims were to investigate a possible difference in effectiveness between athletes with high and low proprioceptive acuity, and whether predictors

  9. Outcome and clinical signs of arthroscopically graded patellar chondromalacia with or without lateral release.

    Science.gov (United States)

    Korkala, O L; Isotalo, T M; Lavonius, M I; Niskanen, R O

    1995-01-01

    In a follow-up study of 67 patients with an arthroscopically diagnosed patellar chondromalacia, we compared the results of plain conservative treatment with those after an open lateral retinacular release. The mean follow-up was 35 months. In Grade I chondromalacia the lateral release did not affect the result, which was in all cases good or excellent. In Grade II to IV chondromalacia the lateral release appeared beneficial, although the difference did not reach statistical significance. We also examined the validity of three clinical signs in arthroscopically verified patellar chondromalacia. Patellar inhibition and tracking tests were clearly more sensitive than the lateral apprehension test, which often gave a false negative result. If the patellar inhibition test is positive and a Grade II to IV chondromalacia of the patella is found at arthroscopy, lateral release should be considered among other procedures, like patellar shaving or patellar resurfacing.

  10. Repair of Medial Patellofemoral, Ligament Improves Patellar, Tracking in Total Knee Replacement.

    Science.gov (United States)

    Meneghini, R Michael; Ziemba-Davis, Mary; Smits, Shelly; Bicos, James

    2015-11-01

    The medial patellofemoral ligament (MPFL) is essential to maintain patella stability; however, its role in total knee replacement (TKR) has not been studied. Forty-six consecutive TKRs in 40 patients were reviewed. Standard closure was performed in 29 TKRs. The MPFL was isolated and anatomically re-approximated in 17 subsequent TKRs. Blinded radiographic evaluation of patellar tilt and subluxation was performed preoperatively and 4 months postoperatively. Despite greater preoperative lateral tilt, the MPFL repair group demonstrated greater correction in patellar tilt compared with the standard closure group (p = 0.02). Patellar tracking also was optimized in the MPFL group, despite equivalent preoperative lateral patellar subluxation in the two groups. Simple repair of the MPFL at arthrotomy closure appears to optimize patellar stability radiographically and may improve long-term results by minimizing patellar complications and wear.

  11. Influence of patellar type and localization on chondromaliacia of patella, magnetic resonanse diagnostics

    OpenAIRE

    Žukauskas, Tomas

    2017-01-01

    Tomas Žukauskas Master’s thesis – influence of patellar type and localization on chondromaliacia of patella, magnetic resonanse diagnostics. Academic supervisor Prof. Eglė Monastyreckienė. Place of study was Lithuanian University of Health Sciences, Radiology department. The aim of study: to investigate the link between patellar type and localization with chondromaliacia of the patella using magnetic resonanse imaging. The objectives were: to investigate patellar type’s influence on its ch...

  12. Fibrocartilage in the attachment zones of the quadriceps tendon and patellar ligament of man.

    OpenAIRE

    Evans, E J; Benjamin, M; Pemberton, D J

    1990-01-01

    Differences are reported in the quantities and distribution of uncalcified fibrocartilage at the attachment sites of the quadriceps tendon and the patellar ligament. The largest quantity of fibrocartilage was characteristic of the quadriceps tendon. A prominent wedge of fibrocartilage was seen in the proximal part of the tibial attachment of the patellar ligament, though there was no fibrocartilage in the most superficial fibres. Little fibrocartilage was seen at the patellar attachment of th...

  13. Dosimetry of a silicone breast prosthesis

    International Nuclear Information System (INIS)

    McGinley, P.H.; Powell, W.R.; Bostwick, J.

    1980-01-01

    Dose measurements were conducted in a phantom which simulates breast tissue and in another phantom which simulates a breast containing a silicone prosthesis. No detectable difference was found when the irradiations were carried out with tangential beams of 60 Co radiation. The degree of backscatter and absorption of radiation by the prosthesis and phantom were also similar. A slight decrease in dose of approximately 8% was found at the interface between the prosthesis and muscle-equivalent material

  14. Malrotation of the McGhan Style 510 prosthesis.

    NARCIS (Netherlands)

    Schots, J.M.; Fechner, M.R.; Hoogbergen, M.M.; Tits, H.W.H.J.

    2010-01-01

    BACKGROUND: Anatomically shaped cohesive silicone breast implants are frequently used in aesthetic and reconstructive surgery. After successful results with the Style 410 prosthesis, McGhan (Natrelle, Allergan) introduced the Style 510 prosthesis. After using this novel prosthesis, the authors

  15. Imaging assessment of anterior knee pain and patellar maltracking

    International Nuclear Information System (INIS)

    McNally, E.G.

    2001-01-01

    Anterior knee pain is a common complaint in the orthopaedic clinic. The differential diagnosis is wide and the principal goal of initial assessment is to detect remediable causes. The majority of patients do not have a specific disease and increasingly interest has focused on the role of patello-femoro-tibial morphology and of patellar maltracking in the aetiology of anterior knee pain. Classification in this group of patients is poor and there is no uniform agreement on which patient groups benefit from treatment and which treatment is best. Much of the literature involves relatively small numbers of patients, is poorly controlled and there is little agreement on outcome measures [1, 2]. The purpose of this review is to outline the current status of the imaging assessment of recalcitrant anterior knee pain with particular reference to patellar maltracking. (orig.)

  16. Nasal prosthesis rehabilitation: a case report

    DEFF Research Database (Denmark)

    Jain, Sumeet; Maru, Kavita; Shukla, Jyotsana

    2011-01-01

    Facial defects resulting from neoplasm, congenital malformation or trauma can be restored with facial prosthesis using different materials and retention methods to achieve life-like look and function. A nasal prosthesis can re-establish esthetic form and anatomic contours for mid-facial defects...... the non-surgical rehabilitation, with polymethyl meth-acrylate resin, nasal prosthesis for a patient who received partial rhinectomy as a result of squamous cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of the patient with a mechanical retained design using...

  17. Microscopically derived free energy of dislocations

    NARCIS (Netherlands)

    Kooiman, M.; Hütter, M.; Geers, M.G.D.

    2015-01-01

    The dynamics of large amounts of dislocations is the governing mechanism in metal plasticity. The free energy of a continuous dislocation density profile plays a crucial role in the description of the dynamics of dislocations, as free energy derivatives act as the driving forces of dislocation

  18. Discrete dislocation modelling of submicron indentation

    NARCIS (Netherlands)

    Widjaja, A; Van der Giessen, E; Needleman, A

    2005-01-01

    Indentation of a planar single crystal by a circular rigid indenter is analyzed using discrete dislocation plasticity. The crystal has three slip systems and is initially dislocation-free, but edge dislocations can nucleate from point sources inside the crystal. The lattice resistance to dislocation

  19. Open versus closed kinetic chain exercises for patellar chondromalacia.

    Science.gov (United States)

    Bakhtiary, A H; Fatemi, E

    2008-02-01

    Conservative treatment of patellar chondromalacia has been the subject of several studies. One recommended treatment is a strengthening exercise of the quadriceps muscle, which may be performed in closed or open kinetic chains. This study was designed to compare the effect of straight leg raise (SLR) and semi-squat exercises on the treatment of patellar chondromalacia, which has not been done to date. 32 female university students with a diagnosis of patellar chondromalacia were randomly assigned to two experimental groups: SLR and semi-squat exercise. Before starting exercise protocols, Q angle, maximal isometric voluntary contraction force (MIVCF) of quadriceps, crepitation, circumference of thigh 5 and 10 cm above the patella and patellofemoral pain according to the visual analogue scale (VAS) were assessed. Both groups then followed a 3-week programme of quadriceps muscle strengthening exercises (SLR or semi-squat) starting with 20 exercises twice a day and increasing each session by 5 exercises every 2 days. All measurements were repeated at the end of each week and then again 2 weeks after the 3-week exercise programme. Reduced Q angle (mean differences (SD) 0.8 (0.3), p = 0.016) and crepitation (19.9 (8.5), p = 0.04), and an increase in the MIVCF of the quadriceps (15.8 (5.6), p = 0.01) and thigh circumference (1.5 (0.3), p = 0.001) were found in semi-squat group compared with SLR group. However, patellofemoral pain was decreased significantly in both groups. The results of this study indicate that semi-squat exercises (closed kinetic chain) are more effective than SLR exercise (open kinetic chain) in the treatment of patellar chondromalacia. More studies are needed to investigate the long-term effect of these types of exercise.

  20. Lateral patellar retinacular release: changes over the last ten years

    Directory of Open Access Journals (Sweden)

    Leonardo Pini Rosalem Marciano da Fonseca

    Full Text Available ABSTRACT Lateral retinacular release is a useful resource in knee surgery that can be used for disorders of the extensor mechanism. For many years, it was indiscriminately used in the treatment of the various patellofemoral joint alterations, with conflicting functional results. This study aimed to analyze the changes that have occurred in the indications and clinical effectiveness of lateral retinacular release by reviewing the relevant literature of the past ten years, comparing it to the classic literature on the subject. It was found that less extensive releases decompress the lateral patellar facet, helping with pain control, while decreasing the risks of medial subluxation. Nowadays, there is clear evidence for its indication in the lateral patellar hypercompression syndrome associated with anterior knee pain, as long as there is no related instability; furthermore, it will normally play an adjuvant role in extensor mechanism alignment surgeries for cases of recurrent patellar instability. The initial results for symptomatic patellofemoral osteoarthritis are promising when lateral release is combined with cartilage debridement; in total knee replacement, it is more commonly used for the correction of valgus deformity in order to improve the components’ congruency. Finally, distinguishing the different patellofemoral joint pathologies is seen as crucial in order to indicate this procedure. Further randomized control trials that compare surgical techniques with long-term results are still needed.

  1. Trans-triquetral Perilunate fracture dislocation

    OpenAIRE

    John-Henry Rhind; Abhinav Gulihar; Andrew Smith

    2018-01-01

    Perilunate dislocations and perilunate fracture dislocations are rare and serious injuries. Perilunate dislocations represent less than 10% of all carpal injuries of which 61% represent transcaphoid fractures. Because of their rarity, up to 25% of perilunate dislocations are initially missed on first assessment. We present the case of a 66-year-old-gentleman who sustained an isolated trans-triquetral perilunate fracture dislocation while walking his dog. This was diagnosed in the emergency de...

  2. HRTEM studies of dislocations in cubic BN

    International Nuclear Information System (INIS)

    Nistor, L.C.; Tendeloo, G. van; Dinca, G.

    2004-01-01

    The atomic structure of dislocations in cubic boron nitride has been investigated by high resolution transmission electron microscopy. Most of the perfect dislocations, screw and 60 edge, are dissociated. A 60 dislocation which was undissociated has been analysed. Computer simulation is performed in an attempt to characterise the core structure. Twinning dislocations and dislocations resulting from the intersection of stacking faults are also revealed. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. HRTEM studies of dislocations in cubic BN

    Energy Technology Data Exchange (ETDEWEB)

    Nistor, L.C. [National Institute for Materials Physics, P.O. Box MG-7 Magurele, 077125 Bucharest (Romania); Tendeloo, G. van [University of Antwerp, EMAT, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Dinca, G. [Dacia Synthetic Diamond Factory, Timisoara av. 5, P.O. Box 58-52, 077350 Bucharest (Romania)

    2004-09-01

    The atomic structure of dislocations in cubic boron nitride has been investigated by high resolution transmission electron microscopy. Most of the perfect dislocations, screw and 60 edge, are dissociated. A 60 dislocation which was undissociated has been analysed. Computer simulation is performed in an attempt to characterise the core structure. Twinning dislocations and dislocations resulting from the intersection of stacking faults are also revealed. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Treatment of Patellar Lower Pole Fracture with Modified Titanium Cable Tension Band Plus Patellar Tibial Tunnel Steel "8" Reduction Band.

    Science.gov (United States)

    Li, Jiaming; Wang, Decheng; He, Zhiliang; Shi, Hao

    2018-01-08

    To determine the efficacy of modified titanium tension band plus patellar tendon tunnel steel 8 "reduction band" versus titanium cable tension band fixation for the treatment of patellar lower pole fracture. 58 patients with lower patella fracture were enrolled in this study, including 30 patients treated with modified titanium cable tension band plus patellar tibial tunnel wire "8" tension band internal fixation (modified group), and 28 patients with titanium cable tension band fixation. All patients were followed up for 9∼15 months with an average of 11.6 months. Knee flexion was significantly improved in the modified group than in the titanium cable tension band group (111.33 ± 13 degrees versus 98.21 ± 21.70 degrees, P = 0.004). The fracture healing time showed no significant difference. At the end of the follow-up, the improvement excellent rate was 93.33% in the modified group, and 82.14% in the titanium cable tension band group. Titanium cable tension band internal fixation loosening was found in 2 cases, including 1 case of treatment by two surgeries without loose internal fixation. The modified titanium cable tension band with "8" tension band fixation showed better efficacy for lower patella fractures than titanium cable tension band fixation.

  5. Prosthesis infections after orthopedic joint replacement

    DEFF Research Database (Denmark)

    Song, Zhijun; Borgwardt, Lotte; Høiby, Niels

    2013-01-01

    Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore...

  6. Femoral Prosthesis Infection by Rhodotorula mucilaginosa▿

    Science.gov (United States)

    Savini, Vincenzo; Sozio, Federica; Catavitello, Chiara; Talia, Marzia; Manna, Assunta; Febbo, Fabio; Balbinot, Andrea; Di Bonaventura, Giovanni; Piccolomini, Raffaele; Parruti, Giustino; D'Antonio, Domenico

    2008-01-01

    This case report is a case history of a femoral prosthesis infection caused by Rhodotorula mucilaginosa in a human immunodeficiency virus patient. Though the pathogenicity of this organism for bone tissue has been previously reported, this is the first reported case of an orthopedic prosthesis infection by this species of the genus Rhodotorula. PMID:18753353

  7. Smartphone supported upper limb prosthesis

    Directory of Open Access Journals (Sweden)

    Hepp D.

    2015-09-01

    Full Text Available State of the art upper limb prostheses offer up to six active DoFs (degrees of freedom and are controlled using different grip patterns. This low number of DoFs combined with a machine-human-interface which does not provide control over all DoFs separately result in a lack of usability for the patient. The aim of this novel upper limb prosthesis is both offering simplified control possibilities for changing grip patterns depending on the patients’ priorities and the improvement of grasp capability. Design development followed the design process requirements given by the European Medical Device Directive 93/42 ECC and was structured into the topics mechanics, software and drive technology. First user needs were identified by literature research and by patient feedback. Consequently, concepts were evaluated against technical and usability requirements. A first evaluation prototype with one active DoF per finger was manufactured. In a second step a test setup with two active DoF per finger was designed. The prototype is connected to an Android based smartphone application. Two main grip patterns can be preselected in the software application and afterwards changed and used by the EMG signal. Three different control algorithms can be selected: “all-day”, “fine” and “tired muscle”. Further parameters can be adjusted to customize the prosthesis to the patients’ needs. First patient feedback certified the prosthesis an improved level of handling compared to the existing devices. Using the two DoF test setup, the possibilities of finger control with a neural network are evaluated at the moment. In a first user feedback test, the smartphone based software application increased the device usability, e.g. the change within preselected grip patterns and the “tired muscle” algorithm. Although the overall software application was positively rated, the handling of the prosthesis itself needs to be proven within a patient study to be

  8. Extracorporeal shockwave therapy for patellar tendinopathy : a review of the literature

    NARCIS (Netherlands)

    van Leeuwen, M. T.; Zwerver, J.; van den Akker-Scheek, I.

    Background and purpose: Extracorporeal shockwave therapy (EWST) has become a popular treatment for patellar tendinopathy. The purpose of this review was to study the effectiveness of ESWT treatment for patellar tendinopathy; to draft guidelines for an effective treatment protocol of ESWT treatment;

  9. Dislocations and other topological oddities

    Science.gov (United States)

    Pieranski, Pawel

    2016-03-01

    We will show that the book Dislocations by Jacques Friedel, published half a century ago, can still be recommended, in agreement with the author's intention, as a textbook ;for research students at University and for students at engineering schools as well as for research engineers;. Indeed, today dislocations are known to occur not only in solid crystals but also in many other systems discovered more recently such as colloidal crystals or liquid crystals having periodic structures. Moreover, the concept of dislocations is an excellent starting point for lectures on topological defects occurring in systems equipped with order parameters resulting from broken symmetries: disclinations in nematic or hexatic liquid crystals, dispirations in chiral smectics or disorientations in lyotropic liquid crystals. The discussion of dislocations in Blue Phases will give us an opportunity to call on mind Sir Charles Frank, friend of Jacques Friedel since his Bristol years, who called these ephemeral mesophases ;topological oddities;. Being made of networks of disclinations, Blue Phases are similar to Twist Grain Boundary (TGB) smectic phases, which are made of networks of screw dislocations and whose existence was predicted by de Gennes in 1972 on the basis of the analogy between smectics and superconductors. We will stress that the book by Jacques Friedel contains seeds of this analogy.

  10. Comparative validation of the radiographic and tomographic measurement of patellar height

    Directory of Open Access Journals (Sweden)

    Marco Antonio Schueda

    2013-09-01

    Full Text Available OBJECTIVE: To evaluate and validate the radiographic measurement of patellar height with computerized tomography scans. METHODS: Measured the patellar height through the lateral radiographic image supported by one foot and sagittal tomographic view of the knee in extension, flexion of 20°, and quadriceps contraction of 40 patients (80 knees, asymptomatic and no history of knee injuries using Insall-Salvati index. There were 20 adult females and 20 adult males. RESULTS: The height patellar index was higher in women of all images taken, in proportion. There was no statistical difference of patellar height index between the radiographics and tomographics images. CONCLUSION: The Insall-Salvati index in females was higher in all cases evaluated. Furthermore, it is possible to measure the patellar height index during tomographic study without distorting the results obtained, using to define the presence of patella alta or patella baja.

  11. A continuum theory of edge dislocations

    Science.gov (United States)

    Berdichevsky, V. L.

    2017-09-01

    Continuum theory of dislocation aims to describe the behavior of large ensembles of dislocations. This task is far from completion, and, most likely, does not have a "universal solution", which is applicable to any dislocation ensemble. In this regards it is important to have guiding lines set by benchmark cases, where the transition from a discrete set of dislocations to a continuum description is made rigorously. Two such cases have been considered recently: equilibrium of dislocation walls and screw dislocations in beams. In this paper one more case is studied, equilibrium of a large set of 2D edge dislocations placed randomly in a 2D bounded region. The major characteristic of interest is energy of dislocation ensemble, because it determines the structure of continuum equations. The homogenized energy functional is obtained for the periodic dislocation ensembles with a random contents of the periodic cell. Parameters of the periodic structure can change slowly on distances of order of the size of periodic cells. The energy functional is obtained by the variational-asymptotic method. Equilibrium positions are local minima of energy. It is confirmed the earlier assertion that energy density of the system is the sum of elastic energy of averaged elastic strains and microstructure energy, which is elastic energy of the neutralized dislocation system, i.e. the dislocation system placed in a constant dislocation density field making the averaged dislocation density zero. The computation of energy is reduced to solution of a variational cell problem. This problem is solved analytically. The solution is used to investigate stability of simple dislocation arrays, i.e. arrays with one dislocation in the periodic cell. The relations obtained yield two outcomes: First, there is a state parameter of the system, dislocation polarization; averaged stresses affect only dislocation polarization and cannot change other characteristics of the system. Second, the structure of

  12. Prediction of dislocation boundary characteristics

    DEFF Research Database (Denmark)

    Winther, Grethe

    Plastic deformation of both fcc and bcc metals of medium to high stacking fault energy is known to result in dislocation patterning in the form of cells and extended planar dislocation boundaries. The latter align with specific crystallographic planes, which depend on the crystallographic......) and it is found that to a large extent the dislocations screen each other’s elastic stress fields [3]. The present contribution aims at advancing the previous theoretical analysis of a boundary on a known crystallographic plane to actual prediction of this plane as well as other boundary characteristics....... Crystal plasticity calculations combined with the hypothesis that these boundaries separate domains with local differences in the slip system activity are introduced to address precise prediction of the experimentally observed boundaries. The presentation will focus on two cases from fcc metals...

  13. Patellar tendinopathy in junior basketball players: a controlled clinical and ultrasonographic study of 268 patellar tendons in players aged 14-18 years.

    Science.gov (United States)

    Cook, J L; Khan, K M; Kiss, Z S; Griffiths, L

    2000-08-01

    Anterior knee pain is a common presenting complaint amongst adolescent athletes. We hypothesised that patellar tendinopathy may occur at a younger age than is generally recognised. Thus, we studied the patellar tendons in 134 elite 14- to 18-year-old female (n=64) and male (n=70) basketball players and 29 control swimmers (17 female, 12 male) clinically and with ultrasonography. We found that of 268 tendons, 19 (7%) had current patellar tendinopathy on clinical grounds (11% in males, 2% in females). Twenty-six percent of the basketball players' patellar tendons contained an ultrasonographic hypoechoic region. Ultrasonographic abnormality was more prevalent in the oldest tertile of players (17-18 years) than the youngest tertile (14-15.9 years). Of tendons categorised clinically as 'Never patellar tendinopathy', 22% had an ultrasonographic hypoechoic region nevertheless. This study indicates that patellar tendinopathy can occur in 14- to 18-year-old basketball players. Ultrasonographic tendon abnormality is 3 times as common as clinical symptoms.

  14. Relaxation strain measurements in cellular dislocation structures

    International Nuclear Information System (INIS)

    Tsai, C.Y.; Quesnel, D.J.

    1984-01-01

    The conventional picture of what happens during a stress relaxation usually involves imagining the response of a single dislocation to a steadily decreasing stress. The velocity of this dislocation decreases with decreasing stress in such a way that we can measure the stress dependence of the dislocation velocity. Analysis of the data from a different viewpoint enables us to calculate the apparent activation volume for the motion of the dislocation under the assumption of thermally activated glie. Conventional thinking about stress relaxation, however, does not consider the eventual fate of this dislocation. If the stress relaxes to a low enough level, it is clear that the dislocation must stop. This is consistent with the idea that we can determine the stress dependence of the dislocation velocity from relaxation data only for those cases where the dislocation's velocity is allowed to approach zero asymptotically, in short, for those cases where the dislocation never stops. This conflict poses a dilemma for the experimentalist. In real crystals, however, obstacles impede the dislocation's progress so that those dislocations which are stopped at a given stress will probably never resume motion under the influence of the steadily declining stress present during relaxation. Thus one could envision stress relaxation as a process of exhaustion of mobile dislocations, rather than a process of decreasing dislocation velocity. Clearly both points of view have merit and in reality both mechanisms contribute to the phenomena

  15. Irreducible Traumatic Posterior Shoulder Dislocation

    Directory of Open Access Journals (Sweden)

    Blake Collier

    2017-01-01

    Full Text Available History of present illness: A 22-year-old male presented to the Emergency Department complaining of right shoulder pain after a motocross accident. He was traveling at approximately 10 mph around a turn when he lost control and was thrown over the handlebars, landing directly on his right shoulder. On arrival, he was holding his arm in adduction and internal rotation. An area of swelling was noted over his anterior shoulder. He was unable to abduct his shoulder. No humeral gapping was noted. He had normal neuro-vascular status distal to the injury. Significant findings: Radiographs demonstrated posterior displacement of the humeral head on the “Y” view (see white arrow and widening of the glenohumeral joint space on anterior-posterior view (see red arrow. The findings were consistent with posterior dislocation and a Hill-Sachs type deformity. Sedation was performed and reduction was attempted using external rotation, traction counter-traction. An immediate “pop” was felt during the procedure. Post-procedure radiographs revealed a persistent posterior subluxation with interlocking at posterior glenoid. CT revealed posterior dislocation with acute depressed impaction deformity medial to the biceps groove with the humeral head perched on the posterior glenoid, interlocked at reverse Hill-Sachs deformity (see blue arrow. Discussion: Posterior shoulder dislocations are rare and represent only 2% of all shoulder dislocations. Posterior shoulder dislocations are missed on initial diagnosis in more than 60% of cases.1 Posterior shoulder dislocations result from axial loading of the adducted and internally rotated shoulder, violent muscle contractions (resulting from seizures or electrocution, a direct posterior force applied to the anterior shoulder.1 Physical findings include decreased anterior prominence of the humeral head, increased palpable posterior prominence of the humeral head below the acromion, increased palpable prominence of the

  16. Bipolar dislocation of the clavicle

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2012-01-01

    Full Text Available Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup.

  17. Treatment and follow-up of a locked posterior shoulder dislocation

    DEFF Research Database (Denmark)

    Schmal, Hagen; Klemt, Christof; Südkamp, Norbert P.

    2004-01-01

    Posterior shoulder dislocation appears to be a rare event and is a frequently overlooked problem in traumatology. Once the diagnosis is made, usually by clinical examination and use of conventional radiography, head damage should be evaluated by an arthro-CT of the shoulder. In case of severe...... humeral head damage and advanced age, arthroplasty of the shoulder seems to provide a reliable treatment method. Implantation of a new-generation prosthesis in a female patient and follow-up by assessment using the Constant-Murley score are described. © Urban & Vogel....

  18. Chondromalacia induced by patellar subluxation in the rabbit

    DEFF Research Database (Denmark)

    Møller, B.N.; Møller-Larsen, F.; Frich, Lars Henrik

    1989-01-01

    A unilateral patellar malalignment was induced in 20 young and 20 mature rabbits by lateral displacement of the tibial tuberosity, the other knee serving as osteotomized in situ control. At 6 weeks, all the knees appeared macroscopically normal, but histologically definite cartilage degeneration...... was found on the experimental side. At 3 months, macroscopic changes occurred in 5 of 10 mature rabbits, and histologic cartilage degeneration was found in all the experimental knees, most pronounced in mature animals, and particularly in joint facets submitted to high pressure. This experimental model...

  19. Galeazzi's modified technique for recurrent patella dislocation in skeletally immature patients

    International Nuclear Information System (INIS)

    Aulisa, A.G.; Falciglia, F.; Giordano, M.; Savignoni, P.; Guzzanti, V.

    2012-01-01

    A large number of surgical techniques have been proposed for the treatment of recurrent patellar dislocation in adolescents, one of the most famous being Galeazzi's semitendinosus tenodesis as modified by Baker. The aim of this study was to verify the mid-term results of this technique, the effectiveness of restoring the patellofemoral congruency, by both static and dynamic computed tomography (CT), and to determine whether the preoperative type of patellofemoral relationship affects the results. The study included 14 patients (16 knees), with a mean age of 11.6 years, Tanner stage ≤3, with at least two to three episodes of patellar dislocation. The patients underwent surgery using Baker's modification of Galeazzi's technique. All 14 patients were evaluated preoperatively and at least 4 years afterward by static and dynamic CT. Clinical evaluation at follow-up was performed using the criteria described by Crosby and Insall. Clinical results at follow-up were excellent in 62.5% and good in 37.5%. As preoperative evaluation showed a high patella in 7 out of 16 knees, two groups were considered: A, high patella; B, not high patella. The data obtained with static CT show that the patella reached a satisfactory congruence in all knees. The data obtained with dynamic CT showed different results between group A and B. A preoperative high patella remains high with quadriceps contraction and again shows the change of tilt and subluxation. In group B, the data obtained with dynamic CT are comparable with those obtained with static CT. This technique produces good mid-term clinical results. However, the dynamic CT showed that in those patients with high patellas, semitendinosus tenodesis alone is not enough to stabilize the patella. (author)

  20. Patients with hip prosthesis: radiotherapy treatment planning considerations

    International Nuclear Information System (INIS)

    Ganesh, K.M.; Supe, Sanjay S.

    2000-01-01

    The number of patients with hip prosthesis undergoing radiotherapy for pelvic cancer worldwide is increasing. This might be of importance depending on the materials in the prosthesis and whether any of the treatment fields are involved in the prosthesis. Radiotherapy planning involving the pelvic region of patients having total hip prosthesis has been found to be difficult due to the effect of the prosthesis on the dose distribution. This review is intended to project dosimetric considerations and possible solutions to this uncommon problem

  1. The movement of screw dislocations in tungsten

    International Nuclear Information System (INIS)

    Tian Xiaogeng; Woo Chungho

    2004-01-01

    Using Acland potential for tungsten, the movement of 1/2a screw dislocation under shear stress was investigated by molecular dynamics simulation. Equilibrated core structure was obtained by relaxation of screw dislocation with proper boundary conditions. We found that the equilibrium dislocation core has three-fold symmetry and spread out in three direction on {1 1 0} planes. The screw dislocation core could not keep the original shape when the shear stress applied. The dislocation could not move until the shear stress became large enough. The dislocation moved in zigzag when the shear stress neared the Peierls stress. When the shear stress became larger, the dislocation moved in zigzag at the beginning and than moved almost in straight line in [2-bar11] direction. The large shear stress applied, the long distance moved before the dislocation stilled in z-direction and the large velocity in y-direction

  2. Stretch due to Penile Prosthesis Reservoir Migration

    Directory of Open Access Journals (Sweden)

    E. Baten

    2016-03-01

    Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

  3. Effect of a patellar strap on the joint position sense of the symptomatic knee in athletes with patellar tendinopathy.

    Science.gov (United States)

    de Vries, Astrid J; van den Akker-Scheek, Inge; Haak, Svenja L; Diercks, Ron L; van der Worp, Henk; Zwerver, Johannes

    2017-11-01

    The primary aim of this study was to investigate the effect of a patellar strap on the proprioception of the symptomatic leg in PT. Secondary aims were to investigate a possible difference in effectiveness between athletes with high and low proprioceptive acuity, and whether predictors of effectiveness could be found. Randomised cross-over pilot study. 24 athletes with PT (age 27.3±9.0, VISA-P 50.6±11.2) performed a joint position sense test with and without a patellar strap. The difference between both conditions was analysed using linear mixed-model analysis. No improvement in the joint position sense using the strap for the whole group was found, while those classified as having low proprioceptive acuity did improve using the strap (p=0.015, 17.2%). A larger knee girth, longer duration of symptoms and more tendon abnormalities were negatively associated with the strap's effectiveness. The use of a patellar strap improves the knee joint proprioception - measured with joint position sense - of the symptomatic leg in athletes with poor proprioceptive acuity. Especially athletes with relatively small knee girth, short duration of symptoms and small tendon abnormalities might benefit from the strap. As proprioception plays an important role in motor control, and deficits in proprioception may put an athlete at risk for (re-)injury, these findings may be relevant for prevention as well as rehabilitation purposes in those PT athletes with low proprioceptive acuity. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  4. Posterior Dislocation of the Hip

    African Journals Online (AJOL)

    than 24 hours, and 13 more than 48 hours after injury. (Table II). TABLE If. RESULTS PLOITED AGAINST DELAY IN. REDUCTION OF THE DISLOCATION. Time from injury. (h). Excellent. Poor and fair. Total. 48. 7. 6. 13. Reduction, as a rule, was effected under general anaes-.

  5. Scattering of phonons by dislocations

    International Nuclear Information System (INIS)

    Anderson, A.C.

    1979-01-01

    By 1950, an explicit effort had been launched to use lattice thermal conductivity measurements in the investigation of defect structures in solids. This technique has been highly successful, especially when combined with the measurements of other properties such as optical absorption. One exception has been the study of dislocations. Although dislocations have a profound effect on the phonon thermal conductivity, the mechanisms of the phonon-dislocation interaction are poorly understood. The most basic questions are still debated in the literature. It therefore is pointless to attempt a quantitative comparison between an extensive accumulation of experimental data on the one hand, and the numerous theoretical models on the other. Instead, this chapter will attempt to glean a few qualitative conclusions from the existing experimental data. These results will then be compared with two general models which incorporate, in a qualitative manner, most of the proposed theories of the phonon-dislocation interaction. Until very recently, measurement of thermal conductivity was the only means available to probe the interaction between phonons and defects at phonon frequencies above the standard ultrasonic range of approx. = 10 9 Hz. The introductory paragraphs provide a brief review of the thermal-conductivity technique and the problems which are encountered in practice. There is also a brief presentation of the theoretical models and the complications that may occur in more realistic situations

  6. Formation of dislocation dipoles in irradiated graphite

    International Nuclear Information System (INIS)

    Niwase, Keisuke

    2005-01-01

    Recently, we have proposed a dislocation dipole accumulation model to explain the irradiation-induced amorphization of graphite. However, the structure of dislocation dipole in the hexagonal networks is still an open question at the atomic-level. In this paper, we propose a possible formation process of the dislocation dipole

  7. Decline eccentric squats increases patellar tendon loading compared to standard eccentric squats.

    Science.gov (United States)

    Kongsgaard, M; Aagaard, P; Roikjaer, S; Olsen, D; Jensen, M; Langberg, H; Magnusson, S P

    2006-08-01

    Recent studies have shown excellent clinical results using eccentric squat training on a 25 degrees decline board to treat patellar tendinopathy. It remains unknown why therapeutic management of patellar tendinopathy using decline eccentric squats offer superior clinical efficacy compared to standard horizontal eccentric squats. This study aimed to compare electromyography activity, patellar tendon strain and joint angle kinematics during standard and decline eccentric squats. Thirteen subjects performed unilateral eccentric squats on flat-and a 25 degrees decline surface. During the squats, electromyography activity was obtained in eight representative muscles. Also, ankle, knee and hip joint goniometry was obtained. Additionally, patellar tendon strain was measured in vivo using ultrasonography as subjects maintained a unilateral isometric 90 degrees knee angle squat position on either flat or 25 degrees decline surface. Patellar tendon strain was significantly greater (Psquat position on the decline surface compared to the standard surface. The stop angles of the ankle and hip joints were significantly smaller during the decline compared to the standard squats (Psquats (Psquats. The use of a 25 degrees decline board increases the load and the strain of the patellar tendon during unilateral eccentric squats. This finding likely explains previous reports of superior clinical efficacy of decline eccentric squats in the rehabilitative management of patellar tendinopathy.

  8. Medial subtalar dislocation: Case report

    Directory of Open Access Journals (Sweden)

    Manojlović Radovan

    2010-01-01

    Full Text Available Introduction. Subtalar dislocation (SI is a term that refers to an injury in which there is dislocation of the talonavicular and talocalcanear joint, although the tibiotalar joint is intact. Case Outline. A case of medial subtalar dislocation as a result of basketball injury, so-called 'basketball foot', is presented. Closed reposition in i.v. anaesthesia was performed with the patient in supine position and a knee flexed at 90 degrees. Longitudinal manual traction in line of deformity was carried out in plantar flexion. The reposition continued with abduction and eversion simultaneously increasing dorsiflexion. It was made in the first attempt and completed instantly. Rehabilitation was initiated after 5 weeks of immobilization. One year after the injury, the functional outcome was excellent with full range of motion and the patient was symptom-free. For better interpretation of roentgenogram, bone model of subtalar dislocation was made using the cadaver bone. Conclusion. Although the treatment of such injury is usually successful, diagnosis can be difficult because it is a rare injury, and moreover, X-ray of the injury can be confusing due to superposition of bones. Radiograms revealed superposition of the calcaneus, tarsal and metatarsal bones which was radiographically visualized in the anterior-posterior projection as one osseous block inward from the talus, and on the lateral view as in an osteal block below the tibial bone. Prompt recognition of these injuries followed by proper, delicately closed reduction under anaesthesia is crucial for achieving a good functional result in case of medial subtalar dislocation.

  9. [Classification and Treatment of Sacroiliac Joint Dislocation].

    Science.gov (United States)

    Tan, Zhen; Huang, Zhong; Li, Liang; Meng, Wei-Kun; Liu, Lei; Zhang, Hui; Wang, Guang-Lin; Huang, Fu-Guo

    2017-09-01

    To develop a renewed classification and treatment regimen for sacroiliac joint dislocation. According to the direction of dislocation of sacroiliac joint,combined iliac,sacral fractures,and fracture morphology,sacroiliac joint dislocation was classified into 4 types. Type Ⅰ (sacroiliac anterior dislocation): main fracture fragments of posterior iliac wing dislocated in front of sacroiliac joint. Type Ⅱ (sacroiliac posterior dislocation): main fracture fragments of posterior iliac wing dislocated in posterior of sacroiliac joint. Type Ⅲ (Crescent fracturedislocation of the sacroiliac joint): upward dislocation of posterior iliac wing with oblique fracture through posterior iliac wing. Type ⅢA: a large crescent fragment and dislocation comprises no more than onethird of sacroiliac joint,which is typically inferior. Type ⅢB: intermediatesize crescent fragment and dislocation comprises between one and twothirds of joint. Type ⅢC: a small crescent fragment where dislocation comprises most,but not the entire joint. Different treatment regimens were selected for different types of fractures. Treatment for type Ⅰ sacroiliac joint dislocation: anterior iliac fossa approach pry stripping reset; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅱ sacroiliac joint dislocation: posterior sacroiliac joint posterior approach; sacroiliac joint fixed with sacroiliac screw under computer guidance. Treatment for type ⅢA and ⅢB sacroiliac joint dislocation: posterior sacroiliac joint approach; sacroiliac joint fixed with reconstruction plate. Treatment for type ⅢC sacroiliac joint dislocation: sacroiliac joint closed reduction; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅳ sacroiliac joint dislocation: posterior approach; sacroiliac joint fixed with spinal pelvic fixation. Results of 24 to 72 months patient follow-up (mean 34.5 months): 100% survival,100% wound healing,and 100

  10. Management of displaced comminuted patellar fracture with titanium cable cerclage.

    Science.gov (United States)

    Yang, Li; Yueping, Ouyang; Wen, Yuan

    2010-08-01

    Management of a displaced comminuted patellar fracture is challenging. Tension band wiring and lag screw fixation are not suitable for such a fracture pattern. Stainless steel wiring with various configurations has been the mainstay of treatment. However, issues of loss of fixation and breakage of wire have not been resolved yet. Partial or total patellectomy is the last resort with a detrimental effect on quadriceps power. Braided titanium cable is stronger in tensile strength and better in fatigue resistance than the stainless steel monofilament wire, and the tension of fixation could be controlled by a graded instrument in its application. We used titanium cable to treat 21 consecutive patients with displaced comminuted patellar fracture. Patients were followed up for a mean period of 24 months (12 to 32 months). The mean score at the final follow-up was 27 points (25 to 30) using the Böstman method. There was no complication except breakage of one cable at the sixth week after the operation and the fracture had united despite the breakage. This technique is simple and effective for these difficult fractures and avoided prolonged immobilisation of the knee. Copyright 2010 Elsevier B.V. All rights reserved.

  11. The reliability of four widely used patellar height ratios.

    Science.gov (United States)

    van Duijvenbode, Dennis; Stavenuiter, Michel; Burger, Bart; van Dijke, Cees; Spermon, Jacco; Hoozemans, Marco

    2016-03-01

    The objective of this study was to evaluate the inter-observer reliability and the intra-observer reliability of four patellar height ratios: Insall-Salvati (IS), modified Insall-Salvati (MIS), Blackburne-Peel (BP) and Caton-Deschamps (CD). The patellar height ratios were assessed by four independent examiners using weight-bearing lateral knee radiographs in 30° flexion. Intra-class correlation coefficients and Fleiss' kappa's were determined. The inter-observer reliability was excellent for the IS and moderate for the other ratios. When the ratio values were categorized, the inter-observer reliability was strong for the IS, moderate for the MIS and BP, and poor for the CD. The intra-observer reliability was excellent for the IS, MIS and CD, and strong for the BP. When the ratio values were categorized, the intra-observer reliability was strong for the IS and MIS, and moderate for the other ratios. Although the IS showed best reliability, we advise to use the MIS as it showed the second best reliability but is, according to the literature, associated with better validity.

  12. Correlation of 3D Shift and 3D Tilt of the Patella in Patients With Recurrent Dislocation of the Patella and Healthy Volunteers: An In Vivo Analysis Based on 3-Dimensional Computer Models.

    Science.gov (United States)

    Yamada, Yuzo; Toritsuka, Yukiyoshi; Nakamura, Norimasa; Horibe, Shuji; Sugamoto, Kazuomi; Yoshikawa, Hideki; Shino, Konsei

    2017-11-01

    The concepts of lateral deviation and lateral inclination of the patella, characterized as shift and tilt, have been applied in combination to evaluate patellar malalignment in patients with patellar dislocation. It is not reasonable, however, to describe the 3-dimensional (3D) positional relation between the patella and the femur according to measurements made on 2-dimensional (2D) images. The current study sought to clarify the relation between lateral deviation and inclination of the patella in patients with recurrent dislocation of the patella (RDP) by redefining them via 3D computer models as 3D shift and 3D tilt. Descriptive laboratory study. Altogether, 60 knees from 56 patients with RDP and 15 knees from 10 healthy volunteers were evaluated. 3D shift and tilt of the patella were analyzed with 3D computer models created by magnetic resonance imaging scans obtained at 10° intervals of knee flexion (0°-50°). 3D shift was defined as the spatial distance between the patellar reference point and the midsagittal plane of the femur; it is expressed as a percentage of the interepicondylar width. 3D tilt was defined as the spatial angle between the patellar reference plane and the transepicondylar axis. Correlations between the 2 parameters were assessed with the Pearson correlation coefficient. The patients' mean Pearson correlation coefficient was 0.895 ± 0.186 (range, -0.073 to 0.997; median, 0.965). In all, 56 knees (93%) had coefficients >0.7 (strong correlation); 1 knee (2%), >0.4 (moderate correlation); 2 knees (3%), >0.2 (weak correlation); and 1 knee (2%), correlation). The mean correlation coefficient of the healthy volunteers was 0.645 ± 0.448 (range, -0.445 to 0.982; median, 0.834). A statistically significant difference was found in the distribution of the correlation coefficients between the patients and the healthy volunteers ( P = .0034). When distribution of the correlation coefficients obtained by the 3D analyses was compared with that by the 2

  13. 21 CFR 878.3720 - Tracheal prosthesis.

    Science.gov (United States)

    2010-04-01

    ...) Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone... of the trachea or trachealbronchial tree. It may be unbranched or contain one or two branches. The...

  14. Finger prosthesis: a boon to handicapped.

    Science.gov (United States)

    Gupta, Ridhima; Kumar, Lakshya; Rao, Jitendra; Singh, Kamleshwar

    2013-08-29

    This is a clinical case report of a 52-year-old male patient with four partially missing fingers of the left hand. The article describes the clinical and laboratory procedure of making prosthesis with modern silicone material. A wax pattern was fabricated using the right hand of the patient. A special type of wax was formulated to make the pattern so that it can be easily moulded and carved. Intrinsic and extrinsic staining was also performed to match the adjacent skin colour. The patient was given the finger prosthesis and was asked to use a half glove (sports) to mask the junction between the prosthesis and the normal tissue. It also provides additional retention to the artificial fingers. The patient felt his social acceptance improved after wearing the finger prosthesis.

  15. Medial peritalar fracture dislocation of the talar body

    Directory of Open Access Journals (Sweden)

    Jacob B. Stirton

    2015-04-01

    Full Text Available Peritalar fracture dislocations typically involve the talar neck and are classified according to Hawkins. To our knowledge, peritalar fracture dislocation involving the talar body has not been formally reported. In this article, we describe a case of peritalar fracture dislocation of the talar body. Keywords: Peritalar dislocation, Talus fracture, Talar body fracture dislocation, Medial subtalar dislocation

  16. Dislocation of total hip replacement in patients with fractures of the femoral neck.

    Science.gov (United States)

    Enocson, Anders; Hedbeck, Carl-Johan; Tidermark, Jan; Pettersson, Hans; Ponzer, Sari; Lapidus, Lasse J

    2009-04-01

    Total hip replacement is increasingly used in active, relatively healthy elderly patients with fractures of the femoral neck. Dislocation of the prosthesis is a severe complication, and there is still controversy regarding the optimal surgical approach and its influence on stability. We analyzed factors influencing the stability of the total hip replacement, paying special attention to the surgical approach. We included 713 consecutive hips in a series of 698 patients (573 females) who had undergone a primary total hip replacement (n = 311) for a non-pathological, displaced femoral neck fracture (Garden III or IV) or a secondary total hip replacement (n = 402) due to a fracture-healing complication after a femoral neck fracture. We used Cox regression to evaluate factors associated with prosthetic dislocation after the operation. Age, sex, indication for surgery, the surgeon's experience, femoral head size, and surgical approach were tested as independent factors in the model. The overall dislocation rate was 6%. The anterolateral surgical approach was associated with a lower risk of dislocation than the posterolateral approach with or without posterior repair (2%, 12%, and 14%, respectively (p replacement in patients with femoral neck fractures.

  17. THE INFLUENCE OF THE SURGICAL APPROACH CONCERNING DISLOCATION IN TOTAL HIP ARTHROPLASTY.

    Science.gov (United States)

    Vicente, José Ricardo Negreiros; Pires, André Fernandes; Lee, Bruno Takasaki; Leonhardt, Marcos Camargo; Ejnisman, Leandro; Croci, Alberto Tesconi

    2009-01-01

    Our primary aim was to evaluate the occurrence of dislocation of non-cemented total hip arthroplasty, when using the posterior and the direct lateral approaches. We performed a comparative retrospective study with 232 patients submitted to non-cemented total hip arthroplasty, due to the diagnosis of primary or secondary osteoarthritis. The posterior approach was used in 105 patients while direct lateral approach was used in 127 patients. There was only one prosthesis model and the same rehabilitation program and post-operative care was used for all patients. We checked the occurrence of dislocation, the acetabular positioning and also the size of the components. There was only one case of dislocation, treated with closed reduction successfully. This was a 47 year-old female, submitted to direct lateral approach. The mean follow-up time for both groups was 23.7 months, ranging from six to 42 months. The authors conclude that the prevalence of total hip arthroplasty dislocation is similar for both approaches, and educational measures besides the use of a higher femoral offset seem to reduce the risk of this complication.

  18. Communication Protocol for Advanced Prosthesis Components

    OpenAIRE

    Karnå, David

    2007-01-01

    It would be of great value for the prosthesis industry to achieve an open standard for communication in upper limb prostheses. Cooperation between NTNU and the University of New Brunswick has resulted in a functional requirements specification for such a standard, SCIP(Standardised Communication Interface in Prostheses). The special challenges for communication in a prosthesis system are possible noisy environments, high demands for light weight, safety for the user and the fact that devices ...

  19. Overuse tendinosis, not tendinitis part 2: applying the new approach to patellar tendinopathy.

    Science.gov (United States)

    Cook, J L; Khan, K M; Maffulli, N; Purdam, C

    2000-06-01

    Patellar tendinopathy causes substantial morbidity in both professional and recreational athletes. The condition is most common in athletes of jumping sports such as basketball and volleyball, but it also occurs in soccer, track, and tennis athletes. The disorder arises most often from collagen breakdown rather than inflammation, a tendinosis rather than a tendinitis. Physicians must address the degenerative pathology underlying patellar tendinopathy because regimens that seek to minimize (nonexistent) inflammation would appear illogical. Suggestions for applying the 'tendinosis paradigm' to patellar tendinopathy management include conservative measures such as load reduction, strengthening exercises, and massage. Surgery should be considered only after a long-term and appropriate conservative regimen has failed.

  20. Atomistic simulations of dislocation processes in copper

    DEFF Research Database (Denmark)

    Vegge, T.; Jacobsen, K.W.

    2002-01-01

    We discuss atomistic simulations of dislocation processes in copper based on effective medium theory interatomic potentials. Results on screw dislocation structures and processes are reviewed with particular focus on point defect mobilities and processes involving cross slip. For example......, the stability of screw dislocation dipoles is discussed. We show that the presence of jogs will strongly influence cross slip barriers and dipole stability. We furthermore present some new results on jogged edge dislocations and edge dislocation dipoles. The jogs are found to be extended, and simulations...

  1. An experimental study of dislocation loop nucleation

    International Nuclear Information System (INIS)

    Bounaud, J.Y.; Leteurtre, J.

    1975-01-01

    The nucleation of dislocation loops is experimentally studied by observing the demixion of the Burgers vectors of dislocation loops nucleated in copper whiskers irradiated in flexion by fission fragments at room temperature. The demixion of Burgers vectors is observed by the dimensional effects of dislocation loops: after irradiation, the applied stress is removed; the whisker shows a residual strain that is due to loops because, after an annealing treatment to evaporate dislocation loops, each whisker recovers its initial straight shape. Everywhere along the whisker, the radius of curvature is measured and plotted vs the max. applied stress. Estimations of the interstitial and vacancy dislocation loop nuclei are derived [fr

  2. Dislocation motion in tungsten: Atomistic input to discrete dislocation simulations

    Czech Academy of Sciences Publication Activity Database

    Srivastava, K.; Gröger, Roman; Weygand, D.; Gumbsch, P.

    2013-01-01

    Roč. 47, AUG (2013), s. 126-142 ISSN 0749-6419 R&D Projects: GA ČR GAP204/10/0255; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : body -centered cubic * non-Schmid effects * anomalous slip * discrete dislocation dynamics Subject RIV: BM - Solid Matter Physics ; Magnetism; BM - Solid Matter Physics ; Magnetism (UFM-A) Impact factor: 5.971, year: 2013

  3. Energetics of dislocation nucleation under a nanoindenter

    International Nuclear Information System (INIS)

    Zhang Chuanli; Xu Guanshui

    2005-01-01

    We present an analysis of dislocation nucleation under an idealized nanoindenter based on the variational boundary integral formulation of the Peierls-Nabarro dislocation model. By solving the embryonic dislocation profiles, corresponding to the relative displacements between the two adjacent atomic layers along the slip plane, we have determined the critical conditions for athermal dislocation nucleation as well as the activation energies required to thermally activate embryonic dislocations from their stable to unstable saddle point configurations. The effect of the size of the indenter on the energetics of dislocation nucleation is quantitatively characterized. The result is compared with a simplified analysis based on the application of the Rice model for dislocation nucleation at a crack tip

  4. Theory of interacting dislocations on cylinders.

    Science.gov (United States)

    Amir, Ariel; Paulose, Jayson; Nelson, David R

    2013-04-01

    We study the mechanics and statistical physics of dislocations interacting on cylinders, motivated by the elongation of rod-shaped bacterial cell walls and cylindrical assemblies of colloidal particles subject to external stresses. The interaction energy and forces between dislocations are solved analytically, and analyzed asymptotically. The results of continuum elastic theory agree well with numerical simulations on finite lattices even for relatively small systems. Isolated dislocations on a cylinder act like grain boundaries. With colloidal crystals in mind, we show that saddle points are created by a Peach-Koehler force on the dislocations in the circumferential direction, causing dislocation pairs to unbind. The thermal nucleation rate of dislocation unbinding is calculated, for an arbitrary mobility tensor and external stress, including the case of a twist-induced Peach-Koehler force along the cylinder axis. Surprisingly rich phenomena arise for dislocations on cylinders, despite their vanishing Gaussian curvature.

  5. Energetics of dislocation nucleation under a nanoindenter

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chuanli [College of Mechanical Engineering, Yangtze University, Jingzhou, Hubei 434023 (China); Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States); Xu Guanshui [Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States)]. E-mail: guanshui.xu@ucr.edu

    2005-07-25

    We present an analysis of dislocation nucleation under an idealized nanoindenter based on the variational boundary integral formulation of the Peierls-Nabarro dislocation model. By solving the embryonic dislocation profiles, corresponding to the relative displacements between the two adjacent atomic layers along the slip plane, we have determined the critical conditions for athermal dislocation nucleation as well as the activation energies required to thermally activate embryonic dislocations from their stable to unstable saddle point configurations. The effect of the size of the indenter on the energetics of dislocation nucleation is quantitatively characterized. The result is compared with a simplified analysis based on the application of the Rice model for dislocation nucleation at a crack tip.

  6. High volume ultrasound guided injections at the interface between the patellar tendon and Hoffa's body are effective in chronic patellar tendinopathy: A pilot study.

    Science.gov (United States)

    Crisp, Tom; Khan, Faisal; Padhiar, Nat; Morrissey, Dylan; King, John; Jalan, Rosy; Maffulli, Nicola; Frcr, Otto Chan

    2008-01-01

    To evaluate a novel conservative management modality for patellar tendinopathy. We recruited nine patients with patellar tendinopathy who had failed conservative management and showed evidence of neovascularisation on power Doppler scanning. A high volume ultrasound guided injection at the interface between the patellar tendon and Hoffa's body. The injection contained 10 ml 0.5% Bupivacaine, 25 mg Hydrocortisone, and between 12 and 40 ml normosaline. 100 mm visual analogue scales (VAS) for pain and for function, and Victorian Institute of Sport Assessment - Patellar tendon (VISA-P) questionnaires at an average of 9 months from the injection. All but one patient (whose pain was unchanged) improved (p = 0.028). The mean improvement in function 2 weeks after injection was 58 mm on VAS (interquartile range 27 - 88, p = 0.018). The mean improvement in pain 2 weeks after injection was 56 mm on a VAS scale (interquartile range 32 - 80, p = 0.018). At a mean follow up of 9 months, an improvement of 22 points from a baseline score of 46 on the VISA-P questionnaire (100 being normal) was established. High volume injections to mechanically disrupt the neovascularisation in patellar tendinopathy are helpful in the management of this condition. Controlled trials would be warranted to investigate in a more conclusive fashion this management modality.

  7. Arthroscopic treatment of acromioclavicular dislocation

    Directory of Open Access Journals (Sweden)

    Mihai T. Gavrilă

    2017-11-01

    Full Text Available A thorough understanding of biomechanical function of both acromioclavicular (AC and coracoclavicular (CC ligaments, stimulated surgeons to repair high-grade AC dislocation using arthroscopic technique. This technique necessitates a clear understanding of shoulder anatomy, especially of the structures in proximity to the clavicle and coracoid process and experiences in arthroscopic surgery. The follow case describes an arthroscopic technique used to treat AC dislocation in young man 30 years old, who suffered an injury at right shoulder. Results were similar to those obtained using open surgery and this encouraged us to continue utilization of this method. As a conclusion, arthroscopic treatment of AC separation is one of the best options as surgical treatment. Early results suggested that immediate anatomic reduction of an acute AC separation usually provides satisfactory clinical results at intermediate-term follow-up.

  8. Regional strain variations in the human patellar tendon.

    Science.gov (United States)

    Pearson, Stephen J; Ritchings, Tim; Mohamed, Azlan S A

    2014-07-01

    Characteristics of localized tendon strain in vivo are largely unknown. The present study examines local tendon strain between the deep, middle, and surface structures at the proximal and distal aspects of the patellar tendon during ramped isometric contractions. Male subjects (age 28.0 ± 6.3 yr) were examined for patellar tendon excursion (anterior, midsection, and posterior) during ramped isometric voluntary contractions using real-time B-mode ultrasonography and dynamometry. Regional tendon excursion measurements were compared using an automated pixel tracking method. Strain was determined from the tendon delta length normalized to initial/resting segment length. Strain increased from 10% to 100% of force for all regions. Significantly greater mean strain was seen for the anterior proximal region compared to the posterior and mid layer of the tendon (7.5% ± 1.1% vs 3.7% ± 0.5% vs 5.5% ± 1.0%; P < 0.05). Similarly, the distal posterior region showed greater mean strain compared to the mid and anterior regions (7.9% ± 0.6% vs 5.0% ± 0.6% vs 5.4% ± 0.6%; P < 0.05). Relative changes in strain differences from 50% to 100% of force for the proximal region were greatest for the anterior to midline regions (4.6% ± 0.6% and 5.6% ± 0.6%, respectively) and those for the distal region were also greatest for the anterior to midline regions (4.4% ± 0.2% and 5.3% ± 0.2%, respectively). The largest mean strain for the proximal region was at the anterior layer (7.5% ± 1.1%) and that for the distal tendon region was at the posterior layer (7.9% ± 0.9%). This study shows significant regional differences in strain during ramped isometric contractions for the patellar tendon. Lower proximal strains in the posterior tendon compared to the anterior region may be associated with the suggestion of "stress shielding" as an etiological factor in insertional tendinopathy.

  9. Previously identified patellar tendinopathy risk factors differ between elite and sub-elite volleyball players.

    Science.gov (United States)

    Janssen, I; Steele, J R; Munro, B J; Brown, N A T

    2015-06-01

    Patellar tendinopathy is the most common knee injury incurred in volleyball, with its prevalence in elite athletes more than three times that of their sub-elite counterparts. The purpose of this study was to determine whether patellar tendinopathy risk factors differed between elite and sub-elite male volleyball players. Nine elite and nine sub-elite male volleyball players performed a lateral stop-jump block movement. Maximum vertical jump, training history, muscle extensibility and strength, three-dimensional landing kinematics (250 Hz), along with lower limb neuromuscular activation patterns (1500 Hz), and patellar tendon loading were collected during each trial. Multivariate analyses of variance (P volleyball players. Interventions designed to reduce landing frequency and improve quadriceps extensibility are recommended to reduce patellar tendinopathy prevalence in volleyball players. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Human syndromes with congenital patellar anomalies and the underlying gene defects.

    NARCIS (Netherlands)

    Bongers, E.M.H.F.; Kampen, A. van; Bokhoven, J.H.L.M. van; Knoers, N.V.A.M.

    2005-01-01

    Genetic disorders characterized by congenital patellar aplasia or hypoplasia belong to a clinically diverse and genetically heterogeneous group of lower limb malformations. Patella development involves different molecular and cellular mechanisms regulating dorso-ventral patterning, cartilage and

  11. Different techniques in fabrication of ocular prosthesis.

    Science.gov (United States)

    Cevik, Pinar; Dilber, Erhan; Eraslan, Oguz

    2012-11-01

    Loss of an eye caused by cancer, trauma, or congenital defect creates a deep psychological impact on an individual's life especially social and professional life. Custom-made prosthesis, compared to stock prosthesis, provides a better fit to the eye socket, better cosmetic results, and less discomfort to the patient in the long term. The main objective of this article was to describe 3 different alternative and practical techniques of fabricating custom-made ocular prosthesis. An impression of anophthalmic socket was made with the addition of cured silicone-based precision impression material in all techniques. A master cast was prepared and duplicated with condensation silicone. A self-cure acrylic resin was polymerized in the silicone model and was fitted into the patient's eye socket. A digital photograph of the patient's iris was made using a digital camera and printed on good-quality photo paper in various shades and sizes in the first and the second techniques. Then the photo paper was coated with PVC so as not to allow any color flowing. The proper iris was then inserted to the acrylic base. The prosthesis was final processed using orthodontic heat polymerizing clear acrylic resin.In the other technique, after the trying-in process with wax pattern, an acrylic base was fabricated using heat polymerizing scleral acrylic resin. The prosthetic iris was fabricated from a transparent contact lens by painting the lens with watercolor paints and attaching it to an acrylic resin with tissue conditioner. The final process was made with heat polymerizing transparent acrylic resin. Custom-made prosthesis allows better esthetic and functional results to the patient in comparison to stock prosthesis. Further follow-up is necessary to check the condition and fit of the ocular prosthesis in such patients.

  12. Factors associated with the presence of patellar tendon abnormalities in male athletes.

    Science.gov (United States)

    Mendonça, Luciana D; Verhagen, Evert; Bittencourt, Natália F N; Gonçalves, Gabriela G P; Ocarino, Juliana M; Fonseca, Sérgio T

    2016-05-01

    To investigate the association between lower limb alignment, range of motion/flexibility and muscle strength with the presence of patellar tendon abnormalities in male athletes. This was a cross-sectional study. Thirty-one male basketball and volleyball athletes were assessed for ankle dorsiflexion range of motion, shank-forefoot alignment, iliotibial band flexibility, hip external rotators and abductors isometric torque, passive hip internal rotation range of motion and frontal plane knee and patellar alignment (McConnell and Arno angles). Ultrasonographic evaluations of hypoechoic areas of the patellar tendons were performed in longitudinal and transverse planes. A receiver operating characteristic curve was used to determine clinically relevant cut-off point for each variable. When the area under the curve was statistically significant, Prevalence Ratio (PR) and 95% confidence intervals were calculated to indicate the strength of the association between the independent variable and the presence of patellar tendon abnormalities. Receiver operating characteristic curve showed that iliotibial band flexibility (p=0.006), shank-forefoot alignment (p=0.013) and Arno angle (p=0.046) were associated with patellar tendon abnormalities. Cut-off points were established and only the Prevalence Ratio of iliotibial band flexibility (cut-off point=-0.02°/kg; PR=5.26) and shank-forefoot alignment (cut-off point=24°; PR=4.42) were statistically significant. Athletes with iliotibial band or shank-forefoot alignment above the clinically relevant cut-off point had more chance to have patellar tendon abnormalities compared to athletes under the cut-off point values. These results suggest that such factors could contribute to patellar tendon overload, since patellar tendon abnormalities indicate some level of tissue damage. Both factors might be considered in future prospective studies. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  13. THE EFFECTS OF EXTRACORPOREAL SHOCKWAVE THERAPY (ESWT) AND CRYOTHERAPY IN TREATING PATELLAR TENDINOPATHIES IN PROFESSIONAL ATHLETES

    OpenAIRE

    Dobreci Iulian

    2014-01-01

    Aim: this paper tries to optimize the existent classical treatments for patellar tendinopathies that are resistant to classical forms of therapy, in professional athletes. Hypotheses: this research wants to highlight the effectiveness of the ESWT and cryotherapy in treating patellar tendinopathies in professional athletes who previously underwent classical treatments that had no positive results. Material: the research was conducted at the Bacau Spinal Care Rehabilitation Clinic, where the sy...

  14. Extracorporeal shockwave therapy for patellar tendinopathy: a review of the literature

    OpenAIRE

    van Leeuwen, M. T.; Zwerver, J.; van den Akker-Scheek, I.

    2009-01-01

    Background and purpose: Extracorporeal shockwave therapy (EWST) has become a popular treatment for patellar tendinopathy. The purpose of this review was to study the effectiveness of ESWT treatment for patellar tendinopathy; to draft guidelines for an effective treatment protocol of ESWT treatment; and to identify topics for further research. Methods: A computerised search of the Medline and Embase databases was conducted on 1 August 2007, to identify studies dealing with the effectiveness of...

  15. The effect of eccentric exercise on injured patellar tendon healing in rats: a gene expression study

    OpenAIRE

    Yagishita, Masafumi

    2011-01-01

    Recently, clinical studies have suggested that eccentric exercise can be beneficial for patellar tendinopathy. It is known that loading induces collagen synthesis in tendon, but the mechanisms responsible for mediating this effect are still unclear. We hypothesized that loading-induced expression of collagen depends on a specific contraction type. Eccentric exercise induces a more beneficial healing response than concentric exercise. Two longitudinal incisions were made in rat patellar tendon...

  16. Differences in tendon properties in elite badminton players with or without patellar tendinopathy.

    Science.gov (United States)

    Couppé, C; Kongsgaard, M; Aagaard, P; Vinther, A; Boesen, M; Kjaer, M; Magnusson, S P

    2013-03-01

    The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players with no current or previous patellar tendinopathy (CT group) were included. Magnetic resonance imaging was used to assess distal patellar tendon dimensions. Patellar tendon mechanical properties were assessed using simultaneous tendon force and deformation measurements. Distal tendon cross-sectional area (CSA) normalized for body weight (mm(2) /kg(2/3) ) was lower in the PT group compared with the CT group on both the non-lead extremity (6.1 ± 0.3 vs 7.4 ± 0.2, P < 0.05) and the lead extremity (6.5 ± 0.6 vs 8.4 ± 0.3, P < 0.05). Distal tendon stress was higher in the PT group compared with the CT group for both the non-lead extremity (31 ± 1 vs 27 ± 1 MPa, P < 0.05) and the lead extremity (32 ± 3 vs 21 ± 3 MPa, P < 0.01). Conclusively, the PT group had smaller distal patellar tendon CSA on both the injured (lead extremity) and the uninjured side (non-lead extremity) compared with the CT group. Subsequently, the smaller CSA yielded a greater distal patellar tendon stress in the PT group. Therefore, a small tendon CSA may predispose to the development of tendinopathy. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  17. Does the adolescent patellar tendon respond to 5 days of cumulative load during a volleyball tournament?

    Science.gov (United States)

    van Ark, M; Docking, S I; van den Akker-Scheek, I; Rudavsky, A; Rio, E; Zwerver, J; Cook, J L

    2016-02-01

    Patellar tendinopathy (jumper's knee) has a high prevalence in jumping athletes. Excessive load on the patellar tendon through high volumes of training and competition is an important risk factor. Structural changes in the tendon are related to a higher risk of developing patellar tendinopathy. The critical tendon load that affects tendon structure is unknown. The aim of this study was to investigate patellar tendon structure on each day of a 5-day volleyball tournament in an adolescent population (16-18 years). The right patellar tendon of 41 players in the Australian Volleyball Schools Cup was scanned with ultrasound tissue characterization (UTC) on every day of the tournament (Monday to Friday). UTC can quantify structure of a tendon into four echo types based on the stability of the echo pattern. Generalized estimating equations (GEE) were used to test for change of echo type I and II over the tournament days. Participants played between eight and nine matches during the tournament. GEE analysis showed no significant change of echo type percentages of echo type I (Wald chi-square = 4.603, d.f. = 4, P = 0.331) and echo type II (Wald chi-square = 6.070, d.f. = 4, P = 0.194) over time. This study shows that patellar tendon structure of 16-18-year-old volleyball players is not affected during 5 days of cumulative loading during a volleyball tournament. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Extracorporeal shockwave therapy for patellar tendinopathy: a review of the literature.

    Science.gov (United States)

    van Leeuwen, M T; Zwerver, J; van den Akker-Scheek, I

    2009-03-01

    Extracorporeal shockwave therapy (EWST) has become a popular treatment for patellar tendinopathy. The purpose of this review was to study the effectiveness of ESWT treatment for patellar tendinopathy; to draft guidelines for an effective treatment protocol of ESWT treatment; and to identify topics for further research. A computerised search of the Medline and Embase databases was conducted on 1 August 2007, to identify studies dealing with the effectiveness of ESWT for patellar tendinopathy. Seven articles describing the effectiveness of ESWT on patellar tendinopathy, all published after 2000, were included. These studies included a total of 283 patients (298 tendons), 204 of whom (215 tendons) were assigned to ESWT treatment. The treatment results were positive but most studies had methodological deficiencies, small numbers and/or short follow-up periods. Method of application and shockwave generation, energy level, number and frequency of treatments, use of (local) anaesthesia and method of localisation were variable. ESWT seems to be a safe and promising treatment for patellar tendinopathy with a positive effect on pain and function. Based on current knowledge it is impossible to recommend a specific treatment protocol. Further basic and clinical research into the working mechanism and effectiveness of ESWT for patellar tendinopathy are necessary.

  19. Surface Area of Patellar Facets: Inferential Statistics in the Iraqi Population

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Imam

    2017-01-01

    Full Text Available Background. The patella is the largest sesamoid bone in the body; its three-dimensional complexity necessitates biomechanical perfection. Numerous pathologies occur at the patellofemoral unit which may end in degenerative changes. This study aims to test the presence of statistical correlation between the surface areas of patellar facets and other patellar morphometric parameters. Materials and Methods. Forty dry human patellae were studied. The morphometry of each patella was measured using a digital Vernier Caliper, electronic balance, and image analyses software known as ImageJ. The patellar facetal surface area was correlated with patellar weight, height, width, and thickness. Results. Inferential statistics proved the existence of linear correlation of total facetal surface area and patellar weight, height, width, and thickness. The correlation was strongest for surface area versus patellar weight. The lateral facetal area was found persistently larger than the medial facetal area, the p value was found to be <0.001 (one-tailed t-test for right patellae, and another significant p value of < 0.001 (one-tailed t-test was found for left patellae. Conclusion. These data are vital for the restoration of the normal biomechanics of the patellofemoral unit; these are to be consulted during knee surgeries and implant designs and can be of an indispensable anthropometric, interethnic, and biometric value.

  20. In Vivo Patellar Tracking and Patellofemoral Cartilage Contacts during Dynamic Stair Ascending

    Science.gov (United States)

    Suzuki, Takashi; Hosseini, Ali; Li, Jing-Sheng; Gill, Thomas J; Li, Guoan

    2012-01-01

    The knowledge of normal patellar tracking is essential for understanding of the knee joint function and for diagnosis of patellar instabilities. This paper investigated the patellar tracking and patellofemoral joint contact locations during a stair ascending activity using a validated dual-fluoroscopic imaging system. The results showed that the patellar flexion angle decreased from 41.9° to 7.5° with the knee extension during stair ascending. During first 80% of the activity, the patella shifted medially about 3.9 mm and then slightly shifted laterally during the last 20% of the ascending activity. Anterior translation of 13 mm of the patella was measured at the early 80% of the activity and then slightly moved posteriorly by about 2 mm at the last 20% of the activity. The path of the cartilage contact points was slightly lateral on the cartilage surfaces of patella and femur. On the patellar cartilage surface, the cartilage contact locations were about 2 mm laterally from heel strike to 60% of the stair ascending activity and moved laterally and reached 5.3 mm at full extension. However, the cartilage contact locations were relatively constant on the femoral cartilage surface (~5 mm lateral). The patellar tracking pattern was consistent with the patellofemoral cartilage contact location pattern. These data could provide baseline knowledge for understanding of normal physiology of the patellofemoral joint and can be used as a reference for clinical evaluation of patellofemoral disorder symptoms. PMID:22840488

  1. Concurrent patellar fracture and lateral collateral ligament avulsion as a result of trauma in three horses.

    Science.gov (United States)

    McLellan, Jonathan; Plevin, Sarah; Taylor, Elizabeth

    2012-05-15

    3 horses were evaluated because of lameness and swelling of the stifle joint subsequent to trauma. All horses had characteristic clinical signs of stifle joint pain and effusion. A medial patellar fracture and lateral collateral ligament avulsion fracture were visible ultrasonographically in each. Radiography, including standard as well as flexed lateromedial, cranioproximal-craniodistal oblique (skyline patellar), and laterally stressed caudocranial views, revealed similar findings. Arthroscopic surgery to remove the patellar fracture was attempted in 1 horse with severe desmitis of the lateral collateral ligament; it remained lame afterward. The other 2 horses, with less severe collateral ligament damage, were managed conservatively and returned to athletic use, despite the lack of surgical intervention to repair the patellar fractures. Special radiographic views were necessary for diagnosis of medial patellar fracture and lateral collateral ligament avulsion fracture in the 3 horses. Ultrasonographic findings pertaining to the collateral ligament may be prognostically important in such situations. The severity of a fracture involving ligament avulsion may be the limiting factor in horses with this combined injury, and this factor should be considered prior to attempting surgical correction of patellar fractures.

  2. Orthopaedic measurements with computed radiography: Methodological development, accuracy, and radiation dose with special reference to the weight-bearing lower extremity and the dislocating patella

    International Nuclear Information System (INIS)

    Sanfridsson, J.

    2001-01-01

    The overall aim of this study was to develop and evaluate a measurement system for computed radiography and Picture Archiving and Communication Systems, permitting measurements of long distances and angles in and between related images. The developed measurement system, which was based on the QUESTOR Precision Radiography system, was applied to the weight-bearing knee with special reference to the dislocating patella. The QPR system modified for CR fulfilled the criteria for measuring the weight-bearing knee. The special measuring assistance tools that were developed were important for the implementation of CR and PACS, particularly in workstations programmed for musculoskeletal radiology. The energy imparted to the patient was reduced by 98% at the lowest exposure of the CR-system, compared with our conventional analogue method, without loss of diagnostic accuracy. The CR technique creates a possibility, to an extent not previously feasible, to differentiate the exposure parameters (and thus minimise the radiation dose to the patient) by carefully considering the purpose of the examination. A radiographic method for measuring the rotation of the femur and the tibia, and the patellar translation was developed and applied to healthy volunteers. The introduced patellar variables have yielded new insights into the complex sequence of motions between the femur, tibia, and patella. The patients with a dislocating patella were subdivided into one 'clean' group of spontaneous dislocations and one group with various traumas in the history, which thus resulted in two groups with distinct radiographic differences. The Q-angle was decreased in knees that had suffered dislocations, and the traditional surgical treatment with a further reduction of the Q-angle must be challenged. The use of clinical measurements of the Q-angle was not an optimal way to evaluate the mechanical alignment in the patellofemoral joint under physiological conditions. In this study, we have proved

  3. Life Estimation of Hip Joint Prosthesis

    Science.gov (United States)

    Desai, C.; Hirani, H.; Chawla, A.

    2015-07-01

    Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

  4. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the temporomandibular...

  5. Traumatic hip dislocation: early MRI findings

    International Nuclear Information System (INIS)

    Laorr, A.; Greenspan, A.; Anderson, M.W.; Moehring, H.D.; McKinley, T.

    1995-01-01

    Objective of this study was to present the spectrum of early magnetic resonance imaging (MRI) findings following traumatic dislocation of the femoral head, and to identify any associated injuries. Prospective MRI of both hips was performed on 18 patients within 5 weeks of a traumatic femoral head dislocation. The interval between the time of injury and the imaging studies ranged from 2 to 35 days. Posterior dislocation was present in 14 patients and anterior dislocation in 4 patients. In the majority of cases, we performed axial T1, coronal T1, and coronal T2 * (MPGR) sequences. MRI can effectively identify and quantify the muscle injury and joint effusion that invariably accompany traumatic hip dislocations. It is also useful for demonstrating trabecular bone contusion (trabecular injury) and iliofemoral ligament injury, which occur commonly with acute hip dislocation. (orig./VHE)

  6. Atraumatic Anterior Dislocation of the Hip Joint

    Directory of Open Access Journals (Sweden)

    Tadahiko Ohtsuru

    2015-01-01

    Full Text Available Dislocation of the hip joint in adults is usually caused by high-energy trauma such as road traffic accidents or falls from heights. Posterior dislocation is observed in most cases. However, atraumatic anterior dislocation of the hip joint is extremely rare. We present a case of atraumatic anterior dislocation of the hip joint that was induced by an activity of daily living. The possible causes of this dislocation were anterior capsule insufficiency due to developmental dysplasia of the hip, posterior pelvic tilt following thoracolumbar kyphosis due to vertebral fracture, and acetabular anterior coverage changes by postural factor. Acetabular anterior coverage changes in the sagittal plane were measured using a tomosynthesis imaging system. This system was useful for elucidation of the dislocation mechanism in the present case.

  7. Effects of dislocations on electron channeling

    International Nuclear Information System (INIS)

    George, Juby; Pathak, A P

    2009-01-01

    The phenomenon of electron channeling in a crystal affected by dislocations is considered. Earlier we had considered the quantum aspects of the positron channeling in a crystal bent by dislocations where the effects of longitudinal motion of the particle were also considered along with the transverse motion. In this paper, the effective potential for the electron case is found for the two regions of dislocation-affected channel. There is considerable shift in the potential minima due to dislocations. The frequency and the corresponding spectrum of the channeling radiation due to electrons channeling through the perfect channel and the two regions of dislocation-affected channels are calculated. The spectral distribution of radiation intensity changes with the parameters of dislocation. The continuity of wavefunctions and their derivatives is used at the three boundaries and the reflection and transmission coefficients are found using these boundary conditions in the same way as in the positron case.

  8. Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs

    Science.gov (United States)

    Handford, Matthew L.; Srinivasan, Manoj

    2016-02-01

    Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user’s walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost - even lower than assuming that the non-amputee’s ankle torques are cost-free.

  9. Implant-Retained Auricular Prosthesis: A Case Report

    OpenAIRE

    Ozturk, A. Nilgun; Usumez, Aslihan; Tosun, Zekeriya

    2010-01-01

    Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis. In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This...

  10. Body image and prosthesis satisfaction in the lower limb amputee.

    OpenAIRE

    Murray, Craig; Fox, Jezz

    2002-01-01

    Purpose: This study examines the relationship between prosthesis satisfaction and body image in lower limb prosthesis users, and the gendered variations within these relationships. Method: A total of 44 valid responses were obtained to an Internet survey regarding prosthesis satisfaction, body image, and phantom pain. Spearman Rho correlations were calculated for these three domains. Results: Moderate to high negative correlations were observed between Body Image Disturbance and Prosthesis Sa...

  11. Rare Inferior Shoulder Dislocation (Luxatio Erecta)

    OpenAIRE

    Cift, Hakan; Soylemez, Salih; Demiroglu, Murat; Ozkan, Korhan; Ozden, Vahit Emre; Ozkut, Afsar T.

    2015-01-01

    Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients’ ages were 78, 62, 65, and 76. All patients’ reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitat...

  12. Dislocation density changes in nickel under creep

    International Nuclear Information System (INIS)

    Moiseeva, I.V.; Okrainets, P.N.; Pishchak, V.K.

    1984-01-01

    Variation in dislocation density was studied in the process of nickel creep p at t=900 deg c and σ=2 kgf/mm 2 . The dislocation structure was studied independently by the X-ray technique and transmission electron-microscopy. The e two methods show good conformity of results by comparison. It is concluded that independent determination of dislocation density under creep is possible us sing the X-ray technique

  13. Piles of dislocation loops in real crystals

    International Nuclear Information System (INIS)

    Dubinko, V.I.; Turkin, A.A.; Yanovskij, V.V.

    1985-01-01

    Behaviour of piles of dislocation loops in crystals was studied in order to define metal swelling under irradiation. Energy of pile interaction with point defects and intrinsic pile energy are studied in the framework of the linear elasticity theory. Preference of dislocation pile calculated in the paper decreases with radiation dose hence, material swelling rate also decreases. Creation of conditions, which assume an existence of piles of dislocation loops being stable under irradiation, is of particular interest

  14. Imaging findings of anterior hip dislocations

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Kyle [Mallinckrodt Institute of Radiology, Department of Radiology, St. Louis, MO (United States); Leslie, Michael [Yale School of Medicine, Department of Orthopedics and Rehabilitation, New Haven, CT (United States); Menn, Kirsten; Haims, Andrew [Yale University School of Medicine, Department of Radiology and Biomedical Imaging, New Haven, CT (United States)

    2017-06-15

    Anterior hip dislocations are rare orthopedic emergencies resulting from high-energy trauma and have unique imaging characteristics on radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Imaging findings on CT and MRI allow for the prompt recognition and classification of anterior hip dislocations, which guides patient management and reduces complications. The purpose of this article is to review imaging findings of anterior hip dislocations, specifically focusing on CT and MRI. (orig.)

  15. Relationship between the trochlear groove angle and patellar cartilage morphology defined by 3D spoiled gradient-echo imaging

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Yuko; Tokuda, Osamu; Matsunaga, Naofumi [Yamaguchi University Graduate School of Medicine, Department of Radiology, Yamaguchi (Japan); Fukuda, Kouji [Shunan Memorial Hospital, Division of Radiological Technology, Yamaguchi (Japan); Shiraishi, Gen; Motomura, Tetsuhisa [Shunan Memorial Hospital, Department of Orthopedics Surgery, Yamaguchi (Japan); Kimura, Motoichi [Customer Application Gr., GE Healthcare MR Sales and Marketing Department, Osaka (Japan)

    2012-05-15

    To examine whether the femoral trochlear groove angle (TGA) is a determinant of the patellar cartilage volume and patellar cartilage damage. Patellar cartilage was evaluated by MR imaging in 66 patients (22 males and 44 females) with knee pain. Fat-suppressed 3D spoiled gradient-echo images were used to calculate the cartilage volume and to grade the cartilage damage. The proximal and distal TGAs were measured from axial PD-weighted FSE MR images with fat suppression. For every increase in the TGA at the distal femur, the patellar cartilage volume was significantly increased by 6.07 x 10{sup -3} cm{sup 3} (95% CI: 1.27 x 10{sup -3}, 10.9 x 10{sup -3}) after adjustment for age, gender, and patellar bone volume (P < 0.05). The MR grade of medial patellar cartilage damage progressed as the distal TGA became narrower, although there was no significant correlation between the distal TGA and the MR grading of patellar cartilage damage. A more flattened distal TGA was associated with increased patellar cartilage volume. However, there was no association between TGA and patellar cartilage defects. (orig.)

  16. 21 CFR 878.3800 - External aesthetic restoration prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External aesthetic restoration prosthesis. 878... External aesthetic restoration prosthesis. (a) Identification. An external aesthetic restoration prosthesis... (general controls). The device is exempt from the premarket notification procedures in subpart E of part...

  17. Fabrication of temporary speech bulb prosthesis: A clinical report

    OpenAIRE

    Kasim Mohamed, K.; Anand Kumar, V.; Devi, N.; Padmanaban, T. V.

    2010-01-01

    Maxillofacial prosthesis is an art and science which not only replaces the lost structure sometimes it restores the functions also. Pharyngeal obturator is a prosthesis which closes the palatal and pharyngeal defects and improving the speech and other function. The following case report discusses palatopharyngeal insufficiency, impression procedures, fabrication of prosthesis and improvements in speech.

  18. 21 CFR 872.3960 - Mandibular condyle prosthesis.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the human...

  19. Energy flow around a moving dislocation

    International Nuclear Information System (INIS)

    Koizumi, H; Kirchner, H O K

    2009-01-01

    A dislocation moving in a lattice emits lattice waves. We study the energy flow accompanying the lattice wave emission in a molecular dynamics situation. About two thirds of the static free energy are emitted as lattice waves from the moving dislocation. Work done by the region around the dislocation helps to initiate the motion from the unstable equilibrium state under a small applied stress, or to compensate the energy emitted as lattice waves when the dislocation makes a long distance motion under a larger stress.

  20. Epidemiology of Isolated Acromioclavicular Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Claudio Chillemi

    2013-01-01

    Full Text Available Background. Acromioclavicular (AC joint dislocation is a common shoulder problem. However, information about the basic epidemiological features of this condition is scarce. The aim of this study is to analyze the epidemiology of isolated AC dislocation in an urban population. Materials and Methods. A retrospective database search was performed to identify all patients with an AC dislocation over a 5-year period. Gender, age, affected side and traumatic mechanism were taken into account. X-rays were reviewed by two of the authors and dislocations were classified according to the Rockwood’s criteria. Results. A total of 108 patients, with a mean age of 37.5 years were diagnosed with AC dislocation. 105 (97.2% had an isolated AC dislocation, and 3 (2.8% were associated with a clavicle fracture. The estimated incidence was 1.8 per 10000 inhabitants per year and the male-female ratio was 8.5 : 1. 50.5% of all dislocations occurred in individuals between the ages of 20 and 39 years. The most common traumatic mechanism was sport injury and the most common type of dislocation was Rockwood type III. Conclusions. Age between 20 and 39 years and male sex represent significant demographic risk factors for AC dislocation.

  1. Structure of the Dislocation in Sapphire

    DEFF Research Database (Denmark)

    Bilde-Sørensen, Jørgen; Thölen, A. R.; Gooch, D. J.

    1976-01-01

    Experimental evidence of the existence of 01 0 dislocations in the {2 0} prism planes in sapphire has been obtained by transmission electron microscopy. By the weak-beam technique it has been shown that the 01 0 dislocations may dissociate into three partials. The partials all have a Burgers vector...... of ⅓ 01 0 and are separated by two identical faults. The distance between two partials is in the range 75-135 Å, corresponding to a fault energy of 320±60 mJ/m2. Perfect 01 0 dislocations have also been observed. These dislocations exhibited either one or two peaks when imaged in the (03 0) reflection...

  2. Metal working and dislocation structures

    DEFF Research Database (Denmark)

    Hansen, Niels

    2007-01-01

    Microstructural observations are presented for different metals deformed from low to high strain by both traditional and new metal working processes. It is shown that deformation induced dislocation structures can be interpreted and analyzed within a common framework of grain subdivision on a finer...... and finer scale down to the nanometer dimension, which can be reached at ultrahigh strains. It is demonstrated that classical materials science and engineering principles apply from the largest to the smallest structural scale but also that new and unexpected structures and properties characterize metals...

  3. Smart image processing system for retinal prosthesis.

    Science.gov (United States)

    Weiland, James D; Parikh, Neha; Pradeep, Vivek; Medioni, Gerard

    2012-01-01

    Retinal prostheses for the blind have demonstrated the ability to provide the sensation of light in otherwise blind individuals. However, visual task performance in these patients remains poor relative to someone with normal vision. Computer vision algorithms for navigation and object detection were evaluated for their ability to improve task performance. Blind subjects navigating a mobility course had fewer collisions when using a wearable camera system that guided them on a safe path. Subjects using a retinal prosthesis simulator could locate objects more quickly when an object detection algorithm assisted them. Computer vision algorithms can assist retinal prosthesis patients and low-vision patients in general.

  4. [Lessons from a heart valve prosthesis controversy].

    Science.gov (United States)

    Vandenbroucke, J P; Grobbee, D E

    1998-07-18

    Two lessons are to be learnt from the Björk-Shiley heart valve prosthesis tragedy. In the first place pharmacoepidemiologic studies are seriously hampered by recent privacy legislation. Individual patients carrying such a prosthesis cannot be traced and advised as to their health risks any more, because their legal autonomy has to be respected. This is clearly not to their advantage. In the second place the atmosphere of marketing and litigation and the increasing dependency of researchers on money from sources with conflicting interests is not conducive to a well-informed and balanced judgement of the epidemiological evidence of safety and efficacy of medical treatments.

  5. [CLINICAL APPLICATION OF OXFORD MOBILE-BEARING BIPOLAR PROSTHESIS UNICOMPARTMENTAL KNEE ARTHROPLASTY FOR SINGLE COMPARTMENTAL KNEE OSTEOARTHRITIS].

    Science.gov (United States)

    Wang, Shangzeng; Cheng, Shao; Wang, Yisheng

    2016-01-01

    To evaluate the effectiveness of Oxford mobile-bearing bipolar prosthesis unicompartmental knee arthroplasty (UKA) in the treatment of single compartmental knee osteoarthritis. Between June 2011 and July 2013, 22 cases of single compartmental knee osteoarthritis were treated by Oxford mobile-bearing bipolar prosthesis UKA. Of 22 cases, 8 were male and 14 were female with an average age of 65 years (range, 45-80 years); the left knee was involved in 12 cases, and the right knee in 10 cases, with a mean disease duration of 32.5 months (range, 8-90 months). The mean weight was 55.2 kg (range, 50-65 kg), and the mean body mass index was 20.8 kg/m2 (range, 17-25 kg/m2). Osteoarthritis involved in the single knee medial compartment in all patients. Knee society score (KSS) and range of motion (ROM) were measured to evaluate the knee joint function. Primary healing of incision was obtained in all patients, and there was no complication of infection, bedsore, or deep venous thrombosis. Postoperative follow-up was 2-4 years (mean, 3.2 years). The X-ray films showed good position of prosthesis, no prosthesis dislocation, or periprosthetic infection during follow-up. Knee ROM, KSS function score, and KSS clinical score were significantly improved at 1 week after operation and at last follow-up when compared with preoperative ones (P 0.05). Oxford mobile-bearing bipolar prosthesis UKA is an effective method to treat single compartmental knee osteoarthritis, with the advantages of less trauma, earlier rehabilitation exercise, near physiological state in joint function, and less risk of complications.

  6. A lower limb assessment tool for athletes at risk of developing patellar tendinopathy.

    Science.gov (United States)

    Mann, Kerry J; Edwards, Suzi; Drinkwater, Eric J; Bird, Stephen P

    2013-03-01

    Patellar tendon abnormality (PTA) on diagnostic imaging is part of the diagnostic criteria for patellar tendinopathy. PTA and altered landing strategies are primary risk factors that increase the likelihood of asymptomatic athletes developing patellar tendinopathy. Therefore, the aim of this study was to examine the risk factors that are predictors of the presence and severity of a PTA in junior pre-elite athletes. Ten junior pre-elite male basketball athletes with a PTA were matched with 10 athletes with normal patellar tendons. Participants had patellar tendon morphology, Victorian Institute of Sport Assessment (VISA) score, body composition, lower limb flexibility, and maximum vertical jump height measured before performing five successful stop-jump tasks. During each stop-jump task, both two-dimensional and three-dimensional kinematics and ground reaction forces were recorded. Multiple regression analyses were used to identify factors for estimating PTA presence and severity, and discriminate analysis was used to classify PTA presence. Sixty-eight percent of variance for presence of a PTA was accounted for by hip joint range of motion (ROM) and knee joint angle at initial foot-ground contact (IC) during stop-jump task and quadriceps flexibility, whereas hip joint ROM during stop-jump task and VISA score accounted for 62% of variance for PTA severity. Prediction of the presence of a PTA was achieved with 95% accuracy and 95% cross-validation. An easily implemented, reliable, and valid movement screening tool composed of three criteria enables coaches and/or clinicians to predict the presence and severity of a PTA in asymptomatic athletes. This enables identification of asymptomatic athletes at higher risk of developing patellar tendinopathy, which allows the development of effective preventative measures to aid in the reduction of patellar tendinopathy injury prevalence.

  7. Relationship between patellar mobility and patellofemoral joint cartilage degeneration after anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Ota, Susumu; Kurokouchi, Kazutoshi; Takahashi, Shigeo; Yoda, Masaki; Yamamoto, Ryuichiro; Sakai, Tadahiro

    2017-11-01

    Patellofemoral cartilage degeneration is a potential complication of anterior cruciate ligament reconstruction (ACLR) surgery. Hypomobility of the patella in the coronal plane is often observed after ACLR. Few studies, however, have examined the relationship between cartilage degeneration in the patellofemoral joint and mobility after ACLR. The present study investigated 1) the coronal mobility of the patella after ACLR, 2) the relationship between patellar mobility and cartilage degeneration of the patellofemoral joint, and 3) the relationship between patellar mobility and knee joint function after ACLR. Forty patients who underwent medial hamstring-based ACLR participated in the study. Lateral and medial patellar displacements were assessed with a modified patellofemoral arthrometer, and the absolute values of the displacements were normalized to patient height. The International Cartilage Repair Society (ICRS) cartilage injury classification of the patellar and femoral (trochlear) surfaces, and the Lysholm Knee Scoring Scale were used to evaluate knee function. Lateral and medial patellar displacements were reduced compared with the non-operated knee at the second-look arthroscopy and bone staple extraction operation (second operation; 24.4 ± 7.9 months after ACLR, Ppatellofemoral joint (patella and trochlea) were significantly worse than those pre-ACLR. Neither lateral nor medial patellar mobility, however, were significantly correlated with the ICRS grade or the Lysholm score. Although patellar mobility at approximately 2 years after ACLR was decreased compared to the non-operated knee, small displacement of the patella was not related to cartilage degeneration or knee joint function at the time of the second operation.

  8. Achilles and patellar tendinopathy display opposite changes in elastic properties: A shear wave elastography study.

    Science.gov (United States)

    Coombes, B K; Tucker, K; Vicenzino, B; Vuvan, V; Mellor, R; Heales, L; Nordez, A; Hug, F

    2018-03-01

    To compare tendon elastic and structural properties of healthy individuals with those with Achilles or patellar tendinopathy. Sixty-seven participants (22 Achilles tendinopathy, 17 patellar tendinopathy, and 28 healthy controls) were recruited between March 2015 and March 2016. Shear wave velocity (SWV), an index of tissue elastic modulus, and tendon thickness were measured bilaterally at mid-tendon and insertional regions of Achilles and patellar tendons by an examiner blinded to group. Analysis of covariance, adjusted for age, body mass index, and sex was used to compare differences in tendon thickness and SWV between the two tendinopathy groups (relative to controls) and regions. Tendon thickness was included as a covariate for analysis of SWV. Compared to controls, participants with Achilles tendinopathy had lower SWV at the distal insertion (Mean difference MD; 95% CI: -1.56; -2.49 to -0.62 m/s; P < .001) and greater thickness at the mid-tendon (MD 0.19; 0.05-0.33 cm; P = .007). Compared to controls, participants with patellar tendinopathy had higher SWV at both regions (MD 1.25; 0.40-2.10 m/s; P = .005) and greater thickness proximally (MD 0.17; 0.06-0.29 cm; P = .003). Compared to controls, participants with Achilles and patellar tendinopathy displayed lower Achilles tendon elastic modulus and higher patellar tendon elastic modulus, respectively. More research is needed to explore whether maturation, aging, or chronic load underlie these findings and whether current management programs for Achilles and patellar tendinopathy need to be tailored to the tendon. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Association between patellar cartilage defects and patellofemoral geometry: a matched-pair MRI comparison of patients with and without isolated patellar cartilage defects.

    Science.gov (United States)

    Mehl, Julian; Feucht, Matthias J; Bode, Gerrit; Dovi-Akue, David; Südkamp, Norbert P; Niemeyer, Philipp

    2016-03-01

    To compare the geometry of the patellofemoral joint on magnetic resonance images (MRI) between patients with isolated cartilage defects of the patella and a gender- and age-matched control group of patients without patellar cartilage defects. A total of 43 patients (17 female, 26 male) with arthroscopically verified grade III and IV patellar cartilage defects (defect group) were compared with a matched-pair control group of patients with isolated traumatic rupture of the anterior cruciate ligament without cartilage defects of the patellofemoral joint. Preoperative MRI images were analysed retrospectively with regard to patellar geometry (width, thickness, facet angle), trochlear geometry (dysplasia according to Dejour, sulcus angle, sulcus depth, lateral condyle index, trochlea facet asymmetry, lateral trochlea inclination) and patellofemoral alignment (tibial tuberosity-trochlear groove distance, patella height, lateral patella displacement, lateral patellofemoral angle, patella tilt, congruence angle). In addition to the comparison of group values, the measured values were compared to normal values reported in the literature, and the frequency of patients with pathologic findings was compared between both groups. The defect group demonstrated a significantly higher proximal chondral sulcus angle (p patellofemoral joint. In particular, a flat and shallow trochlea, trochlea dysplasia and patella alta seem to contribute to the development of patellar cartilage defects, which must be taken into consideration when planning to do surgical cartilage repair at the patella. III.

  10. Atomistic simulation of hydrogen dynamics near dislocations in vanadium hydrides

    International Nuclear Information System (INIS)

    Ogawa, Hiroshi

    2015-01-01

    Highlights: • Hydrogen–dislocation interaction was simulated by molecular dynamics method. • Different distribution of H atoms were observed at edge and screw dislocation. • Planner distribution of hydrogen may be caused by partialized edge dislocation. • Hydrogen diffusivity was reduced in both edge and screw dislocation models. • Pipe diffusion was observed for edge dislocation but not for screw dislocation. - Abstract: Kinetics of interstitial hydrogen atoms near dislocation cores were analyzed by atomistic simulation. Classical molecular dynamics method was applied to model structures of edge and screw dislocations in α-phase vanadium hydride. Simulation showed that hydrogen atoms aggregate near dislocation cores. The spatial distribution of hydrogen has a planner shape at edge dislocation due to dislocation partialization, and a cylindrical shape at screw dislocation. Simulated self-diffusion coefficients of hydrogen atoms in dislocation models were a half- to one-order lower than that of dislocation-free model. Arrhenius plot of self-diffusivity showed slightly different activation energies for edge and screw dislocations. Directional dependency of hydrogen diffusion near dislocation showed high and low diffusivity along edge and screw dislocation lines, respectively, hence so called ‘pipe diffusion’ possibly occur at edge dislocation but does not at screw dislocation

  11. Fresh osteochondral allograft transplantation for isolated patellar cartilage injury.

    Science.gov (United States)

    Gracitelli, Guilherme C; Meric, Gokhan; Pulido, Pamela A; Görtz, Simon; De Young, Allison J; Bugbee, William D

    2015-04-01

    The treatment of patellofemoral cartilage injuries can be challenging. Osteochondral allograft (OCA) transplantation has been used as a treatment option for a range of cartilage disorders. To evaluate functional outcomes and survivorship of the grafts among patients who underwent OCA for patellar cartilage injuries. Case series; Level of evidence, 4. An institutional review board-approved OCA database was used to identify 27 patients (28 knees) who underwent isolated OCA transplantation of the patella between 1983 and 2010. All patients had a minimum 2-year follow-up. The mean age of the patients was 33.7 years (range, 14-64 years); 54% were female. Twenty-six (92.9%) knees had previous surgery (mean, 3.2 procedures; range, 1-10 procedures). The mean allograft area was 10.1 cm(2) (range, 4.0-18.0 cm(2)). Patients returned for clinical evaluation or were contacted via telephone for follow-up. The number and type of reoperations were assessed. Any reoperation resulting in removal of the allograft was considered a failure of the OCA transplantation. Patients were evaluated pre- and postoperatively using the modified Merle d'Aubigné-Postel (18-point) scale, the International Knee Documentation Committee (IKDC) pain, function, and total scores, and the Knee Society function (KS-F) score. Patient satisfaction was assessed at latest follow-up. Seventeen of the 28 knees (60.7%) had further surgery after the OCA transplantation; 8 of the 28 knees (28.6%) were considered OCA failures (4 conversions to total knee arthroplasty, 2 conversions to patellofemoral knee arthroplasty, 1 revision OCA, 1 patellectomy). Patellar allografting survivorship was 78.1% at 5 and 10 years and 55.8% at 15 years. Among the 20 knees (71.4%) with grafts in situ, the mean follow-up duration was 9.7 years (range, 1.8-30.1 years). Pain and function improved from the preoperative visit to latest follow-up, and 89% of patients were extremely satisfied or satisfied with the results of the OCA

  12. Formation of disorientations in dislocation structures during plastic deformation

    DEFF Research Database (Denmark)

    Pantleon, W.

    2002-01-01

    Disorientations developing during plastic deformation in dislocation structures are investigated. Based on expected mechanisms for the formation of different types of dislocation boundaries (statistical trapping of dislocations or differently activated slip systems) the formation of the disorient...

  13. Knee dislocations: a magnetic resonance imaging study correlated with clinical and operative findings

    Energy Technology Data Exchange (ETDEWEB)

    Bui, Kimmie L. [Cleveland Clinic, Department of Radiology, Cleveland, OH (United States); Cleveland Clinic, Department of Radiology, HB6, Cleveland, OH (United States); Ilaslan, Hakan; Sundaram, Murali [Cleveland Clinic, Department of Radiology, Cleveland, OH (United States); Parker, Richard D. [Cleveland Clinic, Department of Orthopaedics, Cleveland, OH (United States)

    2008-07-15

    Our objectives were to determine retrospectively the prevalence, patients' demographics, mechanism of injury, combination of torn ligaments, associated intra-articular and extra-articular injuries, fractures, bone bruises, femoral-tibial alignment and neurovascular complications of knee dislocations as evaluated by magnetic resonance (MR) imaging. From 17,698 consecutive knee examinations by magnetic resonance imaging (MRI) over a 6-year period, 20 patients with knee dislocations were identified. The medical records of these patients were subsequently reviewed for relevant clinical history, management and operative findings. The prevalence of knee dislocations was 0.11% [95% confidence interval (95% CI) 0.06-0.16]. There were 16 male patients and four female patients, with ages ranging from 15 years to 76 years (mean 31 years). Fifteen patients had low-velocity injuries (75%), of which 11 were amateur sports related and four were from falls. Four patients (20%) had suffered high-velocity trauma (motor vehicle accidents). One patient had no history available. Anatomic alignment was present at imaging in 16 patients (80%). Eighteen patients had three-ligament tears, two had four-ligament tears. The four-ligament tears occurred with low-velocity injuries. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were torn in every patient; the lateral collateral ligament (LCL) was torn in 50%, and the medial collateral ligament (MCL) in 60%. Intra-articular injuries included meniscal tears (five in four patients), fractures (eight in seven patients), bone bruises (15 patients), and patellar retinaculum tears (eight partial, two complete). The most common extra-articular injury was a complete biceps femoris tendon tear (five, 25%). There were two popliteal tendon tears and one iliotibial band tear. One patient had received a vascular injury following a motor vehicle accident (MVA) and had been treated prior to undergoing MRI. Bone bruises

  14. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    International Nuclear Information System (INIS)

    Xu Yuhua; Zhou Wuneng; Fang Jianan

    2009-01-01

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  15. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    Energy Technology Data Exchange (ETDEWEB)

    Xu Yuhua [College of Information Science and Technology, Donghua University, Shanghai 201620 (China) and Department of Maths, Yunyang Teacher' s College, Hubei 442000 (China)], E-mail: yuhuaxu2004@163.com; Zhou Wuneng [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)], E-mail: wnzhou@163.com; Fang Jianan [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)

    2009-11-15

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  16. Statistics of dislocation pinning at localized obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  17. Dislocation morphology in deformed and irradiated niobium

    International Nuclear Information System (INIS)

    Chang, C.P.

    1977-06-01

    Niobium foils of moderate purity were examined for the morphology of dislocations or defect clusters in the deformed or neutron-irradiated state by transmission electron microscopy. New evidence has been found for the dissociation of screw dislocations into partials on the (211) slip plane according to the Crussard mechanism: (a/2) [111] → (a/3) [111] + (a/6) [111

  18. Palmar dislocation of scaphoid and lunate

    Directory of Open Access Journals (Sweden)

    Khalid Koulali Idrissi

    2011-11-01

    Full Text Available A palmar dislocation of scaphoid and lunate is uncommon. We have found only 19 reported cases in the literature. We reported a simultaneous, divergent dislocation. The closed reduction followed by percutaneous pinning has given a good result without avascular necrosis of any carpal bone.

  19. Interactions between Dislocations and Grain Boundaries

    NARCIS (Netherlands)

    Soer, Wouter Anthon

    2006-01-01

    Dislocations (line defects) and grain boundaries (planar defects) are two types of lattice defects that are crucial to the deformation behavior of metals. Permanent deformation of a crystalline material is microscopically associated with the nucleation and propagation of dislocations, and extensive

  20. Clinical Outcomes of Penile Prosthesis Implantation Surgery

    Directory of Open Access Journals (Sweden)

    Onur Dede

    2016-06-01

    Full Text Available Objective: We aimed to evaluating the outcomes of in­flatable penile prosthesis implantations and partner sat­isfaction. Methods: Data of 52 patients who underwent penile prosthesis implantation in single center between May 2010 and December 2015 were retrospectively analyzed. Types of prosthesis, complication and satisfaction rates of patients were recorded by EDITS (Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire was used. Results: The mean age was 49.2±14.7 years for patients. The mean follow-up durations for 34.3±12.5 months. The mean hospital stay was 3.84±1.52 days. Evaluating of the couples satisfaction revealed that 44 (84% of the patient were very satisfied. There was not any complication and no patient need to underwent revision surgery. Conclusion: Inflatable penile prosthesis implants, with high levels of treatment success, patient and partner sat­isfaction, are effective and safe options for treatment of organic erectile dysfunction with acceptable complication and revision rates.

  1. Case Report: Magnetically retained silicone facial prosthesis ...

    African Journals Online (AJOL)

    Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention. Key words: Magnet ...

  2. Fusion around cervical disc prosthesis: case report.

    NARCIS (Netherlands)

    Bartels, R.H.M.A.; Donk, R.

    2005-01-01

    OBJECTIVE AND IMPORTANCE: Cervical arthroplasty is a relatively new method to maintain motion after cervical anterior discectomy. Two cases are presented in which bony fusion occurred around a cervical disc prosthesis. CLINICAL PRESENTATION: A 30-year-old man and a 49-year-old woman underwent a

  3. Comparison of Range of Motion After Total Knee Prosthesis According to Different Type of Prosthesis

    Directory of Open Access Journals (Sweden)

    Firat Seyfettinoglu

    2016-07-01

    Full Text Available Aim: The aim of this study is to determine the effectiveness and range of motion of different type of knee prosthesis. Material and Method: This study includes 180 of 225 patients (139 F, 41 M, average age: 65, range of age: 51-82 between April 2005 and September 2007 with the diagnosis of gonarthrosis. All patients underwent to primary total knee arthroplasty. Primary osteoartrhritis is the reason of gonarthrosis. The patients with secondary osteoartrhritis were excluded from the study. All the patients were operated by the same surgical team and rehabilitated after surgery. Patella didnt change any patient. PCL was protected in some of the patients and cut some of patients. Totally seven type prosthesis in 16 subgroup were applied to the patients. All measurement were done by the same surgeon. Average follow up period was 31 months (24-49 months. Results: Patients without subgrouping were tested according to the range of motion before and after surgery to the type of the prosthesis trademark. Range of motion was decreased with the usage of Rotaglide and LCS® type of prosthesis. Range of motion didnt change with the usage of Maxim and Kinemax type. The range of motion increased in the other trademark of prosthesis. Flexion angle was increased statistically significant with nexgen® and scorpio® prosthesis (p

  4. [Mid-term effectiveness of total hip arthroplasty with collum femoris preserving prosthesis].

    Science.gov (United States)

    Li, Mingqing; Hu, Yihe; Li, Kanghua; Liao, Qiande; Wen, Ting; Zhong, Da

    2012-08-01

    To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness. Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), posttraumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients. All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P 0.05) except the Harris score (P fair in 6 hips

  5. Estimation of dislocations density and distribution of dislocations during ECAP-Conform process

    Science.gov (United States)

    Derakhshan, Jaber Fakhimi; Parsa, Mohammad Habibi; Ayati, Vahid; Jafarian, Hamidreza

    2018-01-01

    Dislocation density of coarse grain aluminum AA1100 alloy (140 µm) that was severely deformed by Equal Channel Angular Pressing-Conform (ECAP-Conform) are studied at various stages of the process by electron backscattering diffraction (EBSD) method. The geometrically necessary dislocations (GNDs) density and statistically stored dislocations (SSDs) densities were estimate. Then the total dislocations densities are calculated and the dislocation distributions are presented as the contour maps. Estimated average dislocations density for annealed of about 2×1012 m-2 increases to 4×1013 m-2 at the middle of the groove (135° from the entrance), and they reach to 6.4×1013 m-2 at the end of groove just before ECAP region. Calculated average dislocations density for one pass severely deformed Al sample reached to 6.2×1014 m-2. At micrometer scale the behavior of metals especially mechanical properties largely depend on the dislocation density and dislocation distribution. So, yield stresses at different conditions were estimated based on the calculated dislocation densities. Then estimated yield stresses were compared with experimental results and good agreements were found. Although grain size of material did not clearly change, yield stress shown intensive increase due to the development of cell structure. A considerable increase in dislocations density in this process is a good justification for forming subgrains and cell structures during process which it can be reason of increasing in yield stress.

  6. Hearing results using the SMart piston prosthesis.

    Science.gov (United States)

    Fayad, Jose N; Semaan, Maroun T; Meier, Josh C; House, John W

    2009-12-01

    SMart, a newly introduced piston prosthesis for stapedotomy, is a nitinol-based, heat-activated, self-crimping prosthesis. We review our hearing results and postoperative complications using this self-crimped piston prosthesis and compare them with those obtained using stainless steel or platinum piston prostheses. Audiometric results using the SMart piston are identical to those obtained using a conventional piston prosthesis. Retrospective chart review. Private neurotologic tertiary referral center. The 416 ears reviewed included 306 with a SMart prosthesis and 110 conventional prostheses. 61% were women. Mean follow-up time was 5.6 (standard deviation [SD], 6.3 mo) and 6.9 months (SD, 7.0 mo) for the 2 groups, respectively. Stapedotomy using the SMart or a conventional (non-SMart) prosthesis. Audiometric hearing results, including pure-tone average (PTA) and air-bone gap (ABG), and prevalence of postoperative complications. Mean postoperative PTA was 32.6 (SD, 16.8) dB for the SMart group and 29.4 (SD, 13.5) dB for the non-SMart group, with ABGs of 7.6 (SD, 8.9) and 6.0 (SD, 5.2) dB, respectively. Mean change (decrease) in ABG was 18.7 (SD, 13.1) dB for the SMart group and 19.9 (SD, 10.3) dB for the non-SMart group. High-frequency bone PTAs showed overclosure of 2.0 (SD, 7.9) dB for the SMart group and 3.6 (SD, 8.6) dB for the non-SMart group. Postoperative vertigo and tinnitus were infrequent. No significant differences in these audiometric outcomes or complication rates were noted between groups. There was no significant difference in rate of gap closure to within 10 dB (78.3 versus 84.2%, SMart and non-SMart, respectively) or 20 dB (94.2 and 98.0%). Compared with conventional stapes prostheses, the nitinol-based SMart is a safe and reliable stapes prosthesis that eliminates manual crimping without significantly altering the audiometric outcome. Complications are rare, but longer follow-up is needed before establishing long-term stability.

  7. Effects of dislocations on polycrystal anelasticity

    Science.gov (United States)

    Sasaki, Y.; Takei, Y.; McCarthy, C.; Suzuki, A.

    2017-12-01

    Effects of dislocations on the seismic velocity and attenuation have been poorly understood, because only a few experimental studies have been performed [Guéguen et al., 1989; Farla et al., 2012]. By using organic borneol as a rock analogue, we measured dislocation-induced anelasticity accurately over a broad frequency range. We first measured the flow law of borneol aggregates by uniaxial compression tests under a confining pressure of 0.8 MPa. A transition from diffusion creep (n = 1) to dislocation creep (n = 5) was captured at about σ = 1 MPa (40°C-50°C). After deforming in the dislocation creep regime, sample microstructure showed irregular grain shape consistent with grain boundary migration. Next, we conducted three creep tests at σ = 0.27 MPa (diffusion creep regime), σ = 1.3 MPa and σ = 1.9 MPa (dislocation creep regime) on the same sample in increasing order, and measured Young's modulus E and attenuation Q-1 after each creep test by forced oscillation tests. The results show that as σ increased, E decreased and Q-1 increased. These changes induced by dislocations, however, almost fully recovered during the forced oscillation tests performed for about two weeks under a small stress (σ = 0.27 MPa) due to the dislocation recovery (annihilation). In order to constrain the time scale of the dislocation-induced anelastic relaxation, we further measured Young's modulus E at ultrasonic frequency before and after the dislocation creep and found that E at 106 Hz is not influenced by dislocations. Because E at 100 Hz is reduced by dislocations by 10%, the dislocation-induced anelastic relaxation occurs mostly between 102-106 Hz which is at a higher frequency than grain-boundary-induced anelasticity. To avoid dislocation recovery during the anelasticity measurement, we are now trying to perform an in-situ measurement of anelasticity while simultaneously deforming under a high stress associated with dislocation creep. The combination of persistent creep

  8. Dissociated dislocations in Ni: a computational study

    International Nuclear Information System (INIS)

    Szelestey, P.; Patriarca, M.; Kaski, K.

    2005-01-01

    A systematic computational study of the behavior of a (1/2) dissociated screw dislocation in fcc nickel is presented, in which atomic interactions are described through an embedded-atom potential. A suitable external stress is applied on the system, both for modifying the equilibrium separation distance d and moving the dislocation complex. The structure of the dislocation and its corresponding changes during the motion are studied in the framework of the two-dimensional Peierls model, for different values of the ratio d/a', where a' is the period of the Peierls potential. The distance between the edge and screw components of the partials, as well as their widths, undergo a modulation with period a', as the dislocation moves, and the amplitudes of such oscillations are shown to depend on d/a'. The stress profile acting on the dislocation complex is analyzed and the effective Peierls stress is estimated for different values of d/a'

  9. Dynamic aspects of dislocation motion: atomistic simulations

    International Nuclear Information System (INIS)

    Bitzek, Erik; Gumbsch, Peter

    2005-01-01

    Atomistic simulations of accelerating edge and screw dislocations were carried out to study the dynamics of dislocations in a face centered cubic metal. Using two different embedded atom potentials for nickel and a simple slab geometry, the Peierls stress, the effective mass, the line tension and the drag coefficient were determined. A dislocation intersecting an array of voids is used to study dynamic effects in dislocation-obstacle interactions. A pronounced effect caused by inertial overshooting is found. A dynamic line tension model is developed which reproduces the simulation results. The model can be used to easily estimate the magnitude of inertial effects in the interaction of dislocations with localized obstacles for different obstacle strengths, -spacings and temperatures

  10. Rules for Forest Interactions between Dislocations

    International Nuclear Information System (INIS)

    Wickham, L. K.; Schwarz, K. W.; Stoelken, J. S.

    1999-01-01

    The dynamical interactions of dislocations existing on intersecting glide planes have been investigated using numerical simulations based on isotropic linear elastic theory. It is found that such dislocations either repel, attract and form growing junctions, or attract and form bound crossed states. Which of these occurs can be predicted from a surprisingly simple analysis of the initial configurations. The outcome is determined primarily by the angles which the dislocations initially make with the glide-plane intersection edge, and is largely independent of the initial distance between the dislocations, their initial curvature, or ambient applied stresses. The results provide a rule for dealing with forest interactions within the context of large multiple-dislocation computations. (c) 1999 The American Physical Society

  11. Internal stresses, dislocation mobility and ductility

    Science.gov (United States)

    Saada, G.

    1991-06-01

    The description of plastic deformation must take into account individual mechanisms and heterogeneity of plastic strain. Influence of dislocation interaction with forest dislocations and of cross slip are connected with the organization of dipole walls. The latter are described and their development is explained as a consequence of edge effects. Applications are discussed. La description de la déformation plastique doit prendre en compte les interactions individuelles des dislocations et l'hétérogénéité à grande échelle de la déformation plastique. Les interactions des dislocations mobiles avec la forêt de dislocations, le glissement dévié, ont pour effet la création de parois dipolaires. Celles-ci sont décrites et leur développement est appliqué à partir des effets de bord.

  12. The impact of physically demanding work of basketball and volleyball players on the risk for patellar tendinopathy and on work limitations

    NARCIS (Netherlands)

    van der Worp, H.; Zwerver, J.; Kuijer, P. P. F. M.; Frings-Dresen, M. H. W.; van den Akker-Scheek, I.

    2011-01-01

    Patellar tendinopathy is a common injury in jumping athletes. Little is known about work-related etiological factors for patellar tendinopathy and related work limitations. The aim of this study was to identify work-related etiological factors for patellar tendinopathy and to determine the relation

  13. The impact of physically demanding work of basketball and volleyball players on the risk for patellar tendinopathy and on work limitations

    NARCIS (Netherlands)

    Van Der Worp, H.; Zwerver, J.; Kuijer, P.P.F.M.; Frings-Dresen, M.H.W.; Van Den Akker-Scheek, I.

    Patellar tendinopathy is a common injury in jumping athletes. Little is known about work-related etiological factors for patellar tendinopathy and related work limitations. The aim of this study was to identify work-related etiological factors for patellar tendinopathy and to determine the relation

  14. Reproducibility and clinical utility of tendon palpation to detect patellar tendinopathy in young basketball players

    Science.gov (United States)

    Cook, J; Khan, K; Kiss, Z; Purdam, C; Griffiths, L

    2001-01-01

    Background—Palpation is an important clinical test for jumper's knee. Objectives—To (a) test the reproducibility of palpation tenderness, (b) evaluate the sensitivity and specificity of palpation in subjects with clinical symptoms of jumper's knee, and (c) determine whether tenderness to palpation may serve as a useful screening test for patellar tendinopathy. The yardstick for diagnosis of patellar tendinopathy was ultrasonographic abnormality. Methods—In 326 junior symptomatic and asymptomatic athletes' tendons, palpation was performed by a single examiner before ultrasonographic examination by a certified ultrasound radiologist. In 58 tendons, palpation was performed twice to test reliability. Tenderness to palpation was scored on a scale from 0 to 3 where 0 represented no pain, and 1, 2, and 3 represented mild, moderate, and severe tenderness respectively. Results—Patellar tendon palpation was a reliable examination for a single examiner (Pearson r = 0.82). In symptomatic tendons, the positive predictive value of palpation was 68%. As a screening examination in asymptomatic subjects, the positive predictive value of tendon palpation was 36–38%. Moderate and severe palpation tenderness were better predictors of ultrasonographic tendon pathology than absent or mild tenderness (ppatellar tendinopathy in a preparticipation examination. In symptomatic tendons, palpation is a moderately sensitive but not specific test. Mild tenderness in the patellar tendons in asymptomatic jumping athletes should be considered normal. Key Words: patellar tendon; ultrasound; palpation; reliability; athletes PMID:11157466

  15. Patellar tendon-lateral femoral condyle friction syndrome: MR imaging in 42 patients

    International Nuclear Information System (INIS)

    Chung, C.B.; Skaf, A.; Campos, J.; Stump, X.; Resnick, D.; Roger, B.

    2001-01-01

    Objective: To demonstrate the MR imaging findings that occur between the posterior inferolateral patellar tendon and the lateral femoral condyle in patients with chronic anterior and or lateral knee pain. Patients and design: A retrospective review of the MR images in 42 patients who presented with chronic anterior or lateral knee pain was performed by two musculoskeletal radiologists. In 15 patients, post-contrast images were available. Results: Sagittal and axial imaging planes best demonstrated the patellar tendon and its relationship with the lateral femoral condyle. In 40 patients, there was obliteration of the fat planes and abnormal signal intensity in the lateral soft tissues of the inferior patellofemoral joint. Enhancement after administration of gadolinium was noted in all cases in which contrast was administered. Eighteen patients showed cystic changes in the soft tissues adjacent to the lateral femoral condyle in addition to fat plane obliteration. In two patients, only cystic changes were noted in the lateral soft tissues. Abnormal patellar alignment was noted in 37 patients. Patellar tendon pathology was seen in nine patients. Conclusion: In evaluating anterior knee symptoms, MR imaging allows identification of changes that may be related to patellar tendon-lateral femoral condyle friction syndrome and that should be distinguished from other causes of anterior or lateral knee pain. (orig.)

  16. Patellar tendon-lateral femoral condyle friction syndrome: MR imaging in 42 patients

    Energy Technology Data Exchange (ETDEWEB)

    Chung, C.B.; Skaf, A.; Campos, J.; Stump, X.; Resnick, D. [Dept. of Radiology, University of California, San Diego (United States); Roger, B. [Service de Radiologie Polyvalente, Groupe Hospitalier Pitie-Salpetriere, Paris (France)

    2001-12-01

    Objective: To demonstrate the MR imaging findings that occur between the posterior inferolateral patellar tendon and the lateral femoral condyle in patients with chronic anterior and or lateral knee pain. Patients and design: A retrospective review of the MR images in 42 patients who presented with chronic anterior or lateral knee pain was performed by two musculoskeletal radiologists. In 15 patients, post-contrast images were available. Results: Sagittal and axial imaging planes best demonstrated the patellar tendon and its relationship with the lateral femoral condyle. In 40 patients, there was obliteration of the fat planes and abnormal signal intensity in the lateral soft tissues of the inferior patellofemoral joint. Enhancement after administration of gadolinium was noted in all cases in which contrast was administered. Eighteen patients showed cystic changes in the soft tissues adjacent to the lateral femoral condyle in addition to fat plane obliteration. In two patients, only cystic changes were noted in the lateral soft tissues. Abnormal patellar alignment was noted in 37 patients. Patellar tendon pathology was seen in nine patients. Conclusion: In evaluating anterior knee symptoms, MR imaging allows identification of changes that may be related to patellar tendon-lateral femoral condyle friction syndrome and that should be distinguished from other causes of anterior or lateral knee pain. (orig.)

  17. The wrinkled patellar tendon: An indication of abnormality in the extensor mechanism of the knee

    International Nuclear Information System (INIS)

    Berlin, R.C.; Levinsohn, E.M.; Chrisman, H.

    1991-01-01

    Rupture of the quadriceps tendon is an uncommon condition which requires early diagnosis and treatment to avert prolonged disability. In four patients who had surgically confirmed quadriceps tendon rupture, lateral radiographs of the knee and/or sagittal magnetic resonance (MR) images demonstrated a corrugated appearance to the patellar tendon. Sagittal MR images of the knee following patellectomy in one patient and radiographs of a transverse fracture of the patella in another also demonstrated this appearance. MRI has superb contrast resolution which provides optimal visualization of the contour of the patellar tendon on sagittal images. A retrospective review of 50 consecutive knee MRI examinations was carried out to evaluate the appearance of the normal patellar tendon. In 49 of 50 patients, the sagittal images demonstrated a straight or nearly straight patellar tendon. A corrugated appearance of the patellar tendon on sagittal images indicates a reduction in the normal tensile force applied to it and indicates the need for careful evaluation of the patella and quadriceps tendon mechanism. (orig.)

  18. Reading visual braille with a retinal prosthesis.

    Science.gov (United States)

    Lauritzen, Thomas Z; Harris, Jordan; Mohand-Said, Saddek; Sahel, Jose A; Dorn, Jessy D; McClure, Kelly; Greenberg, Robert J

    2012-01-01

    Retinal prostheses, which restore partial vision to patients blinded by outer retinal degeneration, are currently in clinical trial. The Argus II retinal prosthesis system was recently awarded CE approval for commercial use in Europe. While retinal prosthesis users have achieved remarkable visual improvement to the point of reading letters and short sentences, the reading process is still fairly cumbersome. This study investigates the possibility of using an epiretinal prosthesis to stimulate visual braille as a sensory substitution for reading written letters and words. The Argus II retinal prosthesis system, used in this study, includes a 10 × 6 electrode array implanted epiretinally, a tiny video camera mounted on a pair of glasses, and a wearable computer that processes the video and determines the stimulation current of each electrode in real time. In the braille reading system, individual letters are created by a subset of dots from a 3 by 2 array of six dots. For the visual braille experiment, a grid of six electrodes was chosen out of the 10 × 6 Argus II array. Groups of these electrodes were then directly stimulated (bypassing the camera) to create visual percepts of individual braille letters. Experiments were performed in a single subject. Single letters were stimulated in an alternative forced choice (AFC) paradigm, and short 2-4-letter words were stimulated (one letter at a time) in an open-choice reading paradigm. The subject correctly identified 89% of single letters, 80% of 2-letter, 60% of 3-letter, and 70% of 4-letter words. This work suggests that text can successfully be stimulated and read as visual braille in retinal prosthesis patients.

  19. Influence of mobile dislocations on phase separation in binary alloys

    International Nuclear Information System (INIS)

    Haataja, Mikko; Leonard, Francois

    2004-01-01

    We introduce a continuum model to describe the phase separation of a binary alloy in the presence of mobile dislocations. The kinetics of the local composition and dislocation density are coupled through their elastic fields. We show both analytically and numerically that mobile dislocations modify the standard spinodal decomposition process, and lead to several regimes of growth. Depending on the dislocation mobility and observation time, the phase separation may be accelerated, decelerated, or unaffected by mobile dislocations. For any finite dislocation mobility, we show that the domain growth rate asymptotically becomes independent of the dislocation mobility, and is faster than the dislocation-free growth rate

  20. Assessment of patellar maltracking using combined static and dynamic MRI

    International Nuclear Information System (INIS)

    McNally, E.G.; Ostlere, S.J.; Pal, C.; Phillips, A.; Reid, H.; Dodd, C.

    2000-01-01

    Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was present in 188(40%) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild in 51%, moderate in 39% and severe in 10%. Subluxation was more prevalent in females than males (42% vs. 37%) and this was most obvious in the severe group where 68% were female. In 90 knees selected at random, four measurements of patellofemoral morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than 150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified more accurately and the outcomes of treatment more reliably assessed. (orig.)

  1. Assessment of patellar maltracking using combined static and dynamic MRI

    Energy Technology Data Exchange (ETDEWEB)

    McNally, E.G.; Ostlere, S.J.; Pal, C.; Phillips, A.; Reid, H. [Department of Radiology, Nuffield Orthopaedic Centre, Headington, Oxford OX3 9JW (United Kingdom); Dodd, C. [Department of Orthopaedic Surgery, Nuffield Orthopaedic Centre, Headington, Oxford OX3 9JW (United Kingdom)

    2000-07-01

    Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was present in 188(40%) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild in 51%, moderate in 39% and severe in 10%. Subluxation was more prevalent in females than males (42% vs. 37%) and this was most obvious in the severe group where 68% were female. In 90 knees selected at random, four measurements of patellofemoral morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than 150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified more accurately and the outcomes of treatment more reliably assessed. (orig.)

  2. Anthropometry, physical performance, and ultrasound patellar tendon abnormality in elite junior basketball players: a cross-sectional study

    OpenAIRE

    Cook, J; Kiss, Z; Khan, K; Purdam, C; Webster, K

    2004-01-01

    Objective: Patellar tendinopathy has been reported to be associated with many intrinsic risk factors. Few have been fully investigated. This cross-sectional study examined the anthropometric and physical performance results of elite junior basketball players with normal or abnormal patellar tendons to see if any measures were associated with changes in tendon morphology.

  3. Risk factors for patellar tendinopathy in volleyball and basketball players : A survey-based prospective cohort study

    NARCIS (Netherlands)

    de Vries, A. J.; van der Worp, H.; Diercks, R. L.; van den Akker-Scheek, I.; Zwerver, J.

    2015-01-01

    Patellar tendinopathy (PT) is a common overuse injury of the patellar tendon in jumping athletes. In a recent large cross-sectional study from 2008 several factors were identified that may be associated with the etiology of PT. However, because of the study design no conclusions could be drawn about

  4. No effect of extracorporeal shockwave therapy on patellar tendinopathy in jumping athletes during the competitive season : A randomized clinical trial

    NARCIS (Netherlands)

    Zwerver, Johannes; Hartgens, Fred; Verhagen, Evert; van der Worp, Henk; van den Akker-Scheek, Inge; Diercks, Ronald

    Background: Patellar tendinopathy is a common overuse injury among jumping athletes. No evidence-based treatment guidelines exist. Extracorporeal shockwave therapy (ESWT) appears to be a promising treatment but its effectiveness has not been studied in athletes with patellar tendinopathy who have

  5. Patient guided Piezo-electric Extracorporeal Shockwave Therapy as treatment for chronic severe patellar tendinopathy : A pilot study

    NARCIS (Netherlands)

    Zwerver, J.; Dekker, F.; Pepping, G.J.

    2010-01-01

    Background and purpose: Patellar tendinopathy is a common overuse injury for which no evidence-based treatment guidelines exist. Extracorporeal Shock Wave Therapy (ESWT) seems to be an effective treatment for patellar tendinopathy but the most beneficial treatment strategies still need to be

  6. Jumper's Knee or Lander's Knee? : A Systematic Review of the Relation between Jump Biomechanics and Patellar Tendinopathy

    NARCIS (Netherlands)

    van der Worp, Henk; de Poel, H. J.; Diercks, R. L.; van den Akker-Scheek, I.; Zwerver, J.

    Patellar tendinopathy (jumper's knee) is a common injury in sports that comprise jump actions. This article systematically reviews the literature examining the relation between patellar tendinopathy and take-off and landing kinematics in order to uncover risk factors and potential prevention

  7. Patient guided Piezo-electric Extracorporeal Shockwave Therapy as treatment for chronic severe patellar tendinopathy: A pilot study.

    Science.gov (United States)

    Zwerver, Johannes; Dekker, Femke; Pepping, Gert-Jan

    2010-01-01

    Patellar tendinopathy is a common overuse injury for which no evidence-based treatment guidelines exist. Extracorporeal Shock Wave Therapy (ESWT) seems to be an effective treatment for patellar tendinopathy but the most beneficial treatment strategies still need to be ascertained. Aim of this pilot study was to investigate if patient guided Piezo-electric, focused ESWT, without local anesthesia is a safe and well tolerated treatment which improves pain and function in patients with patellar tendinopathy. Nineteen male athletes with severe chronic patellar tendinopathy received 3 patient guided focused medium to high energy ESWT treatments at a weekly interval. Before and after 3 months VISA-P and VAS (pain) scores were recorded. Data on side effects and complications of treatment were also collected. No serious complications were reported and patients tolerated the treatment well. Mean VISA-P score improved from 36.1 to 50.1 (p patellar tendinopathy.

  8. In vivo Evaluation of Patellar Tendon Stiffness in Individuals with Patellofemoral Pain Syndrome

    Directory of Open Access Journals (Sweden)

    Hsin-Yi Liu

    2008-01-01

    Full Text Available The objective of this study was to utilise an ultrasonic technique to assess the effect of patellofemoral pain syndrome (PFPS on the mechanical properties of the patellar tendon. Seven subjects with PFPS and seven matched control subjects volunteered to participate in this study. Subjects were asked to perform isometric maximal voluntary contractions of the knee extensors while their knee extension torque was monitored and the displacement of the patellar tendon was recorded with an ultrasonic system. Our results showed significantly lower tendon stiffness (by ∼30% in the PFPS subjects. Although tendon secant modulus was lower by 34% in the PFPS subjects, the difference was not statistically significant. Therefore, we conclude that the ultrasonic technique was able to detect a decrease in the structural stiffness of the patellar tendon associated with PFPS. The decrease in tendon stiffness was moderately correlated with the length of symptoms in these individuals.

  9. [Distal fixation prosthesis for unstable intertrochanteric fractures in elderly patients: a mid-term follow-up study].

    Science.gov (United States)

    Zhang, Zhan-feng; Min, Ji-kang; Zhong, Jian-ming; Wang, Dan

    2016-06-01

    To explore mid-term follow up results of distal fixation prosthesis in treating unstable intertrochanteric fractures in elderly patients. From May 2008 to March 2014,58 elderly patients with unstable intertrochanteric were treated with distal fixation prosthesis, among them, there were 15 males and 43 females aged from 75 to 87 years old with an average of 83.2 years old. Fracture were classified according to Evans classification, 39 cases were type I c and 19 cases were type I d. Surgical risk was evaluated before operation, 9 patients were performed total hip arthroplasty and 49 patients were performed prosthetic replacement hip joint function of patients with different age period, Evans classificaton, prothesis type, fixation method were evaluated respectively by using Harris score. Fifty-six patients were followed up from 13 to 36 months with an average of 21.6 months. Harris score was 83.51 ± 6.40, 5 cases got excellent results, 38 cases good and 13 cases moderate. Harris score of patients aged from 75 to 80 years old was 88.64 ± 2.35, 81.64 ± 6.40 in patients aged more than 80 years old, and had significant differences between two groups; Harris score in patients with type Evans I c was 83.64 ± 6.53, and 83.11 ± 6.08 in type Evans I d, while there was no significant differences between two groups. There was no obvious meaning in Harris score between patients with tension band (83.63 ± 6.15) and without tension band (82.41 ± 6.57). There was no significant meaning in Harris score between patients with normal distal fixation prosthesis (83.34 ± 6.43) and femoral moment reconstruction distal fixation prosthesis (83.92 ± 6.51). There was 1 patient occurred hip joint dislocation on the operative side and re-dislocation after manual reduction, then received open reduction. Two patients occurred femoral osteolysis without clinical symptoms, and treated conservative treatment. Artificial joint replacement for unstable intertrochanteric fractures in elderly

  10. Dislocation-induced stress in polycrystalline materials: mesoscopic simulations in the dislocation density formalism

    Science.gov (United States)

    Berkov, D. V.; Gorn, N. L.

    2018-06-01

    In this paper we present a simple and effective numerical method which allows a fast Fourier transformation-based evaluation of stress generated by dislocations with arbitrary directions and Burgers vectors if the (site-dependent) dislocation density is known. Our method allows the evaluation of the dislocation stress using a rectangular grid with shape-anisotropic discretization cells without employing higher multipole moments of the dislocation interaction coefficients. Using the proposed method, we first simulate the stress created by relatively simple non-homogeneous distributions of vertical edge and so-called ‘mixed’ dislocations in a disk-shaped sample, which is necessary to understand the dislocation behavior in more complicated systems. The main part of our research is devoted to the stress distribution in polycrystalline layers with the dislocation density rapidly varying with the distance to the layer bottom. Considering GaN as a typical example of such systems, we investigate dislocation-induced stress for edge and mixed dislocations, having random orientations of Burgers vectors among crystal grains. We show that the rapid decay of the dislocation density leads to many highly non-trivial features of the stress distributions in such layers and study in detail the dependence of these features on the average grain size. Finally we develop an analytical approach which allows us to predict the evolution of the stress variance with the grain size and compare analytical predictions with numerical results.

  11. Frenkel defect absorption on dislocations and dislocation discharge rate. Modeling determination of the absorption zone

    International Nuclear Information System (INIS)

    Mikhlin, Eh.Ya.

    1988-01-01

    A situation connected with the fact that evaluations of dislocation discharge strength which somehow or other are based on the elasticity theory in the dislocation nucleus or near it, do not lead to results complying with experimental data, is discussed. Bases of the alternative approach to this problem consisting in direct investigation into the process of Frenkel defect absorption on dislocation by its computerized simulation at the microscopic level are also presented. Methods of investigation and results are described using α dislocation in iron-alpha as an example. The concept of zones of vacancy and interstitial atom absorption on dislocation is discussed. It is shown that a spontaneous transition, performed by any of these defects near a dislocation is not always identical to absorption and usually appears to be only a part of a multistage process leading to the defect disappearance. Potential relief characteristics for vacancy movement near the dislocation are found. An area wide enough in a transverse direction is found around the dislocation. Vacncies reaching this area can be easily transported to places of their disappearance. Therefore the vacancy entry to this area is equivalent to the absorption. the procedure of simulating the atomic structure of a crystallite containing a dislocation with a step is described. Positions from which these defects perform spontaneous transitions, reaching the disappearance places are found on the dislocation near the step

  12. Ultrasonic Study of Dislocation Dynamics in Lithium -

    Science.gov (United States)

    Han, Myeong-Deok

    1987-09-01

    Experimental studies of dislocation dynamics in LiF single crystals, using ultrasonic techniques combined with dynamic loading, were performed to investigate the time evolution of the plastic deformation process under a short stress pulse at room temperature, and the temperature dependence of the dislocation damping mechanism in the temperature range 25 - 300(DEGREES)K. From the former, the time dependence of the ultrasonic attenuation was understood as resulting from dislocation multiplication followed by the evolution of mobile dislocations to immobile ones under large stress. From the latter, the temperature dependence of the ultrasonic attenuation was interpreted as due to the motion of the dislocation loops overcoming the periodic Peierls potential barrier in a manner analogous to the motion of a thermalized sine-Gordon chain under a small stress. The Peierls stress obtained from the experimental results by application of Seeger's relaxation model with exponential dislocation length distribution was 4.26MPa, which is consistent with the lowest stress for the linear relation between the dislocation velocity and stress observed by Flinn and Tinder.

  13. MULTIPLE DAMAGE OF THE TIBIAL POLYETHYLENE INSERT IN KNEE JOINT PROSTHESIS (CAN EXCELLENT POSTOPERATIVE OUTCOME BE THE CAUSE OF FRACTURE OF THE TIBIAL INSERT? CASE REPORT AND LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    E. Song

    2016-01-01

    Full Text Available Despite improvements in prosthesis technology and use of high-quality materials in recent years, the number of revisions related to implant failures (4.7% remains high. Several phenomena were reported in literature as reasons for dislocation and fracture of tibial insert in mobile bearing prosthesis: incorrect positioning of components, discrepancy of extension and flexion balancing or ligament weakness. However, in our cases neither of these causes were observed. The authors consider that bio-physiological and biomechanical aspects of total knee arthroplasty and knee joint prosthesis should be thoroughly studied and implemented into the clinical practice. In the described cases, multiple damage of the insert due to flexion instability and “twist-hyperflexion” in overweight patients is perceived as the reason for failures.

  14. Thermodynamic theory of dislocation-enabled plasticity

    International Nuclear Information System (INIS)

    Langer, J. S.

    2017-01-01

    The thermodynamic theory of dislocation-enabled plasticity is based on two unconventional hypotheses. The first of these is that a system of dislocations, driven by external forces and irreversibly exchanging heat with its environment, must be characterized by a thermodynamically defined effective temperature that is not the same as the ordinary temperature. The second hypothesis is that the overwhelmingly dominant mechanism controlling plastic deformation is thermally activated depinning of entangled pairs of dislocations. This paper consists of a systematic reformulation of this theory followed by examples of its use in analyses of experimentally observed phenomena including strain hardening, grain-size (Hall-Petch) effects, yielding transitions, and adiabatic shear banding.

  15. MR imaging of patellar cartilage degeneration at 0.02 T

    International Nuclear Information System (INIS)

    Koskinen, S.K.; Komu, M.; Aho, H.J.; Kormano, M.; Turku University Hospital

    1991-01-01

    MR imaging with a 0.02 T resistive magnet was used to establish the correlation between the histologic grading of patellar cartilage degeneration and fat water separation images or T1- and T2-relaxation times. We examined 23 cadaveric patellae. There was a positive correlation between histologically graded cartilage degeneration and T1-relaxation time. Patellar cartilage was well differentiated from surrounding structures on chemical shift water proton images, and an evaluation of cartilage degeneration was possible. No correlation was found between cartilage degeneration damage and T2-relaxation time. Chemical shift imaging at 0.02 T is easy to perform and gives further information of cartilage disorders. (orig.)

  16. Distribution of distances between dislocations in different types of dislocation substructures in deformed Cu-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Trishkina, L., E-mail: trishkina.53@mail.ru; Zboykova, N.; Koneva, N., E-mail: koneva@tsuab.ru; Kozlov, E. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); Cherkasova, T. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); National Research Tomsk Polytechnic University, 50 Lenin Ave., Tomsk, 634050 (Russian Federation)

    2016-01-15

    The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocation chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.

  17. Distribution of distances between dislocations in different types of dislocation substructures in deformed Cu-Al alloys

    Science.gov (United States)

    Trishkina, L.; Cherkasova, T.; Zboykova, N.; Koneva, N.; Kozlov, E.

    2016-01-01

    The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocation chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.

  18. Canonical Quantization of Crystal Dislocation and Electron-Dislocation Scattering in an Isotropic Media

    Science.gov (United States)

    Li, Mingda; Cui, Wenping; Dresselhaus, M. S.; Chen, Gang; MIT Team; Boston College Team

    Crystal dislocations govern the plastic mechanical properties of materials but also affect the electrical and optical properties. However, a fundamental and decent quantum-mechanical theory of dislocation remains undiscovered for decades. Here we present an exact and manageable Hamiltonian theory for both edge and screw dislocation line in an isotropic media, where the effective Hamiltonian of a single dislocation line can be written in a harmonic-oscillator-like form, with closed-form quantized 1D phonon-like excitation. Moreover a closed-form, position dependent electron-dislocation coupling strength is obtained, from which we obtained good agreement of relaxation time when comparing with classical results. This Hamiltonian provides a platform to study the effect of dislocation to materials' non-mechanical properties from a fundamental Hamiltonian level.

  19. "Conjugate channeling" effect in dislocation core diffusion: carbon transport in dislocated BCC iron.

    Science.gov (United States)

    Ishii, Akio; Li, Ju; Ogata, Shigenobu

    2013-01-01

    Dislocation pipe diffusion seems to be a well-established phenomenon. Here we demonstrate an unexpected effect, that the migration of interstitials such as carbon in iron may be accelerated not in the dislocation line direction ξ, but in a conjugate diffusion direction. This accelerated random walk arises from a simple crystallographic channeling effect. c is a function of the Burgers vector b, but not ξ, thus a dislocation loop possesses the same everywhere. Using molecular dynamics and accelerated dynamics simulations, we further show that such dislocation-core-coupled carbon diffusion in iron has temperature-dependent activation enthalpy like a fragile glass. The 71° mixed dislocation is the only case in which we see straightforward pipe diffusion that does not depend on dislocation mobility.

  20. Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity

    Directory of Open Access Journals (Sweden)

    Anna E. Denoble

    2010-01-01

    Full Text Available Background Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA. Methods A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. Results The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50–0.72 for the various regions of interest in Controls. Cutaneous temperature of the patella (knee cap yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02. Conclusion The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage.

  1. Patellar skin surface temperature by thermography reflects knee osteoarthritis severity.

    Science.gov (United States)

    Denoble, Anna E; Hall, Norine; Pieper, Carl F; Kraus, Virginia B

    2010-10-15

    Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs) for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50-0.72 for the various regions of interest) in Controls. Cutaneous temperature of the patella (knee cap) yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02). The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage.

  2. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy.

    Science.gov (United States)

    Rio, Ebonie; Kidgell, Dawson; Purdam, Craig; Gaida, Jamie; Moseley, G Lorimer; Pearce, Alan J; Cook, Jill

    2015-10-01

    Few interventions reduce patellar tendinopathy (PT) pain in the short term. Eccentric exercises are painful and have limited effectiveness during the competitive season. Isometric and isotonic muscle contractions may have an immediate effect on PT pain. This single-blinded, randomised cross-over study compared immediate and 45 min effects following a bout of isometric and isotonic muscle contractions. Outcome measures were PT pain during the single-leg decline squat (SLDS, 0-10), quadriceps strength on maximal voluntary isometric contraction (MVIC), and measures of corticospinal excitability and inhibition. Data were analysed using a split-plot in time-repeated measures analysis of variance (ANOVA). 6 volleyball players with PT participated. Condition effects were detected with greater pain relief immediately from isometric contractions: isometric contractions reduced SLDS (mean±SD) from 7.0±2.04 to 0.17±0.41, and isotonic contractions reduced SLDS (mean±SD) from 6.33±2.80 to 3.75±3.28 (peffect on inhibition (pre 30.26±3.89, post 31.92±4.67; p=0.004). Condition by time analysis showed pain reduction was sustained at 45 min postisometric but not isotonic condition (ptendon pain immediately for at least 45 min postintervention and increased MVIC. The reduction in pain was paralleled by a reduction in cortical inhibition, providing insight into potential mechanisms. Isometric contractions can be completed without pain for people with PT. The clinical implications are that isometric muscle contractions may be used to reduce pain in people with PT without a reduction in muscle strength. 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.

  3. Tracheobronchial Foreign Body Aspiration: Dental Prosthesis

    Directory of Open Access Journals (Sweden)

    Ataman Köse

    2014-01-01

    Full Text Available It is important to extract foreign bodies for avoiding life-threatening complications. They can lead to death if they are not treated. Different signs and symptoms could occur according to the complete or partial airway obstruction. Foreign body aspiration is a rare incident in adults. The organic foreign materials such as foods are found to be aspirated more commonly and are usually settled in the right bronchial system. However, dental prosthesis and teeth aspirations are rare in literature. In our study, a 52-year-old male patient who had aspirated the front part of his lower dental prosthesis accidentally is presented and the foreign body is extracted by using rigid bronchoscopy. There are many causes of aspiration but dental prosthetic aspirations should be kept in mind during sleep. For this reason, dental apparatus must be taken out while asleep.

  4. Cyclooxygenase-2 inhibitors and knee prosthesis surgery

    OpenAIRE

    Meunier, Andreas

    2008-01-01

    Adverse effects of cyclooxygenase (COX) inhibitors on bone healing have previously been demonstrated in diaphyseal fracture models in animals. In spite of that, they are widely used as postoperative analgesics in orthopaedic surgery. After joint replacement, a bone repair process starts at the interface between bone and cement. If this process is disturbed, the prosthesis may never become rigidly fixed to the bone, leading to migration and with time loosening. This thesis investigates the eff...

  5. [The esthetics of lower limb prosthesis].

    Science.gov (United States)

    Gardrat, Franck

    2015-01-01

    The amputation, which is upper or lower limb, entails important consequences and often traumatic into subject amputee from a physical, psychological, interpersonal and social point of view. It acts on the body image unleashing different psychological disorders and alterations in the social and professional reality. The aesthetic prosthesis can be considered a good support to help the person regain a new body image of themselves, facilitating the process of physical rehabilitation and social integration.

  6. Control of dental prosthesis system with microcontroller.

    Science.gov (United States)

    Kapidere, M; Müldür, S; Güler, I

    2000-04-01

    In this study, a microcontroller-based electronic circuit was designed and implemented for dental prosthesis curing system. Heater, compressor and valve were controlled by 8-bit PIC16C64 microcontroller which is programmed using MPASM package. The temperature and time were controlled automatically by preset values which were inputted from keyboard while the pressure was kept constant. Calibration was controlled and the working range was tested. The test results showed that the system provided a good performance.

  7. Development and clinical application of a new testicular prosthesis.

    Science.gov (United States)

    Ning, Ye; Cai, Zhikang; Chen, Huixing; Ping, Ping; Li, Peng; Wang, Zhong; Li, Zheng

    2011-11-01

    A new type of testicular prosthesis made of silastic with an elliptical shape to mimic a normal testis was developed by our team and submitted for patenting in China. The prosthesis was produced in different sizes to imitate the normal testis of the patient. To investigate the effects and safety of the testicular prosthesis, 20 patients receiving testicular prosthesis implantation were recruited for this study. Follow-up after 6 months revealed no complications in the patients. All the patients answered that they were satisfied with their body image and the position of the implants, 19 patients were satisfied with the size and 16 patients were satisfied with the weight. These results show that the testicular prosthesis used in this study can meet patient's expectations. Patients undergoing orchiectomy should be offered the option to receive a testicular prosthesis implantation. The dimensions and weight of the available prosthetic implants should be further addressed to improve patient satisfaction.

  8. coccygectomy for chronic, symptomatic coccygeal dislocation

    African Journals Online (AJOL)

    evidence revealed anterior dislocation of terminal two coccygeal vertebrae ... a prominent terminal coccygeal curvature. The patient presented during her first visit with. CT SCAN .... physiotherapy, modified wedge-shaped coccygeal foam pads ...

  9. Mechanisms for decoration of dislocations by small dislocation loops under cascade damage conditions

    DEFF Research Database (Denmark)

    Trinkaus, H.; Singh, B.N.; Foreman, A.J.E.

    1997-01-01

    . This effect may arise as a result of either (a) migration and enhanced agglomeration of single SIAs in the form of loops in the strain field of the dislocation or (b) glide and trapping of SIA loops (produced directly in the cascades) in the strain field of the dislocation, In the present paper, both...... of these possibilities are examined. It is shown that the strain field of the dislocation causes a SIA depletion in the compressive as well as in the dilatational region resulting in a reduced rather than enhanced agglomeration of SIAs. (SIA depletion may, however, induce enhanced vacancy agglomeration near dislocations...

  10. Rehabilitation of amputed thumb with a silicone prosthesis

    OpenAIRE

    Asnani, Pooja; Shivalingappa, Chandu Giriyapura; Mishra, Sunil Kumar; Somkuwar, Kirti; Khan, Faisal

    2015-01-01

    Creating prosthesis, having realistic skin surface and seamless visual integration with the surrounding tissues, requires both artistic and technical skill. Anatomical design, thin margins, lifelike fingernails and realistic color/contours are essential for patient satisfaction. Prosthesis is especially useful in case of lost body parts, as reconstructive surgery cannot fully restore aesthetics. This case report describes a simple technique for fabricating silicon finger prosthesis for a pati...

  11. Self-contained inflatable penile prosthesis: magnetic resonance appearance

    International Nuclear Information System (INIS)

    Levin, M.F.; Munk, P.L.; Vellet, A.D.; Chin, J.L.

    1994-01-01

    The appearance of an inflatable penile prosthesis, visualized on a short tau inversion recovery sequence, is reported, in a patient who had magnetic resonance imaging for pelvic pain subsequent to radical cystoprostatectomy for bladder carcinoma. With suppression of adjacent fat signal, the prosthesis is well delineated from adjacent structures. The fluid-containing cylinders of the prosthesis are of very bright signal intensity, with the relief valve assembly of low signal intensity. 5 refs., 2 figs

  12. Laser-assisted fixation of a nitinol stapes prosthesis.

    Science.gov (United States)

    Schrötzlmair, Florian; Suchan, Fabian; Pongratz, Thomas; Krause, Eike; Müller, Joachim; Sroka, Ronald

    2018-02-01

    Otosclerosis is an inner ear bone disease characterized by fixation of the stapes and consequently progressive hearing loss. One treatment option is the surgical replacement of the stapes by a prosthesis. When so called "smart materials" like nitinol are used, prosthesis fixation can be performed using a laser without manual crimping on the incus. However, specific laser-prosthesis interactions have not been described yet. The aim of the present study was to elucidate the thermo-mechanical properties of the NiTiBOND® prosthesis as a basis for handling instructions for laser-assisted prosthesis fixation. Closure of the NiTiBOND® prosthesis was induced ex vivo by either a diode laser emitting at λ = 940 nm or a CO 2 laser (λ = 10,600 nm). Total energy for closure was determined. Suitable laser parameters (pulse duration, power per pulse, distance between tip of the laser fiber and prosthesis) were assessed. Specific laser-prosthesis interactions were recorded. Especially the diode laser was found to be an appropriate energy source. A total energy deposit of 60 mJ by pulses in near contact application was found to be sufficient for prosthesis closure ex vivo. Energy should be transmitted through a laser fiber equipollent to the prosthesis band diameter. Specific deformation characteristics due to the zonal prosthesis composition have to be taken into account. NiTiBOND® stapes prosthesis can be closed by very little energy when appropriate energy sources like diode lasers are used, suggesting a relatively safe application in vivo. Lasers Surg. Med. 50:153-157, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report

    Directory of Open Access Journals (Sweden)

    Gayatri Shankaran

    2016-08-01

    Full Text Available Rapid prototyping (RP is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D model created in a computer aided design (CAD system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the cranio-maxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

  14. Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report.

    Science.gov (United States)

    Shankaran, Gayatri; Deogade, Suryakant Chhagan; Dhirawani, Rajesh

    2016-01-01

    Rapid prototyping (RP) is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D) model created in a computer aided design (CAD) system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the craniomaxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

  15. Posterior atlantoaxial dislocation without odontoid fracture

    International Nuclear Information System (INIS)

    Chaudhary, Reema; Raut, Abhijit; Chaudhary, Kshitij; Metkar, Umesh; Rathod, Ashok; Sanghvi, Darshana

    2008-01-01

    We report a case of posterior atlantoaxial dislocation without a fracture of the odontoid in a 35-year-old woman. There have been nine reported cases of similar injury in the English literature. The integrity of the transverse ligament following posterior atlantoaxial dislocations has not been well documented in these reports. In the present case, MRI revealed an intact transverse ligament, which probably contributed to the stability of the C1-C2 complex following closed reduction. (orig.)

  16. Hip dysplasia and congenital hip dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Lingg, G.; Nebel, G.; von Torklus, D.

    1981-11-01

    In human genetics and orthopedics quite different answers have been given to the question of hereditary transmission and frequency of hip dysplasia in families of children with congenital hip dislocation. We therefore have made roentgenometric measurements of 110 parents of children with congenital hip dislocation. In 25% we found abnormal flat acetabulae, whereas 12% had pathologic deep hips. This may propose a new concept of morphology of congenital hip dysplasia.

  17. Isolated Proximal Tibiofibular Dislocation during Soccer

    Directory of Open Access Journals (Sweden)

    Casey Chiu

    2015-01-01

    Full Text Available Proximal tibiofibular dislocations are rarely encountered in the Emergency Department (ED. We present a case involving a man presenting to the ED with left knee pain after making a sharp left turn on the soccer field. His physical exam was only remarkable for tenderness over the lateral fibular head. His X-rays showed subtle abnormalities of the tibiofibular joint. The dislocation was reduced and the patient was discharged from the ED with orthopedic follow-up.

  18. Posterior sternoclavicular dislocation: an American football injury

    DEFF Research Database (Denmark)

    Marker, L B; Klareskov, B

    1996-01-01

    Posterior dislocation of the sternoclavicular joint is uncommon, accounting for less than 0.1% of all dislocations. Since 1824 a little more than 100 cases have been reported, and the majority in the past 20 years. A review of published reports suggests that this injury is seen particularly in co...... in connection with American football. A typical case is described. The importance of this injury is that there is often a delay in diagnosis with potentially serious complications....

  19. Transscaphoid, transcapitate, perilunate fracture dislocation (Scaphocapitate syndrome)

    International Nuclear Information System (INIS)

    Resnik, C.S.; Resnick, D.; Gelberman, R.H.

    1983-01-01

    Five cases of transscaphoid, transcapitate, perilunate fracture dislocation have been presented with a discussion of the radiologic findings, mechanism of injury, and the method of treatment. Although a total of only 23 cases have now been reported in the literature, this type of injury is probably not rare as we have seen two cases within a span of six months. It is important to recognize the radiologic features of this fracture dislocation so appropriate therapy may be instituted. (orig.)

  20. Steps and dislocations in cubic lyotropic crystals

    International Nuclear Information System (INIS)

    Leroy, S; Pieranski, P

    2006-01-01

    It has been shown recently that lyotropic systems are convenient for studies of faceting, growth or anisotropic surface melting of crystals. All these phenomena imply the active contribution of surface steps and bulk dislocations. We show here that steps can be observed in situ and in real time by means of a new method combining hygroscopy with phase contrast. First results raise interesting issues about the consequences of bicontinuous topology on the structure and dynamical behaviour of steps and dislocations

  1. Compound transstyloid, transscaphoid, perilunate fracture dislocation

    Directory of Open Access Journals (Sweden)

    Nadeem Ali

    2013-01-01

    Full Text Available Compound fracture dislocations of proximal carpal bones are very rare. We report a 26-year-old male, Defense personnel by profession, who sustained a compound Gustilo Anderson type IIIA transstyloid, transscaphoid, perilunate dislocation. The patient underwent primary proximal row carpectomy and stabilization with uni-planar, uni-lateral external fixator, and K-Wires. On follow-up after a year, the patient had almost negligible range of motion around wrist without any significant discomfort.

  2. Dislocation dynamics of web type silicon ribbon

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Jr, O W; Tsai, C T; DeAngelis, R J

    1987-03-01

    Silicon ribbon grown by the dendritic web process passes through a rapidly changing thermal profile in the growth direction. This rapidly changing profile induces stresses which produce changes in the dislocation density in the ribbon. A viscoplastic material response function (Haasen-Sumino model) is used herein to calculate the stresses and the dislocation density at each point in the silicon ribbon. The residual stresses are also calculated.

  3. Do Changes in Patellofemoral Joint Offset Lead to Adverse Outcomes in Total Knee Arthroplasty With Patellar Resurfacing? A Radiographic Review.

    Science.gov (United States)

    Matz, Jacob; Howard, James L; Morden, David J; MacDonald, Steven J; Teeter, Matthew G; Lanting, Brent A

    2017-03-01

    Patellofemoral joint biomechanics contribute to anterior knee pain, instability, and dysfunction following total knee arthroplasty (TKA). Information about specific factors leading to anterior knee pain and dysfunction is currently limited. Changes in patellofemoral joint offset (PFO) refers to a mismatch between the preoperative and postoperative anteroposterior geometry of the patellofemoral joint. It remains unclear whether these changes lead to adverse outcomes in TKA. A retrospective radiographic review of 970 knees pre-TKA and post-TKA was completed to correlate the radiographic and clinical outcomes of changing the PFO using a posterior-stabilized single knee design with patellar resurfacing. A total of 970 patients were reviewed. Postoperatively, the anterior femoral offset, anteroposterior femoral size, and anterior patellar offset were changed in 40%, 60%, and 71% of knees, respectively, compared to preoperative values. The Western Ontario and McMasters Osteoarthritis Index total score as well as subscale scores for pain and function were not significantly affected by an increase or decrease in PFO. Similarly, Knee Society Scores and range of motion were not significantly affected. Increased anterior patellar offset was, however, associated with increased postoperative patellar tilt. Postoperative patellar tilt was not correlated with adverse patient satisfaction scores or loss of range of motion. Changes in PFO (decreased, maintained, or increased) are common post-TKA and are not associated with a difference in clinical outcomes. Increases in anterior patellar offset led to increased patellar tilt, which was not associated with adverse patient satisfaction scores. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. The epidemiology of shoulder dislocations in Oslo.

    Science.gov (United States)

    Liavaag, S; Svenningsen, S; Reikerås, O; Enger, M; Fjalestad, T; Pripp, A H; Brox, J I

    2011-12-01

    There are few previous studies on the incidence of shoulder dislocation in the general population. The aim of the study was to report the incidence of acute shoulder dislocations in the capital of Norway (Oslo) in 2009. Patients of all ages living in Oslo, sustaining a dislocation of the glenohumeral joint, were identified using electronic diagnosis registers, patient protocols, radiological registers of the hospitals, and the Norwegian Patient Register (NPR). The overall incidence rate was 56.3 [95% confidence interval (CI) 50.2-62.4] per 100,000 person-years, with rates of 82.2 (95% CI 71.7-92.8) and 30.9 (95% CI 24.5-37.3) in men and women, respectively. The incidence of primary dislocations was 26.2 (95% CI 22.1-30.4). The overall incidence of shoulder dislocations in Oslo was higher than previously reported incidences. The incidence of primary dislocations was also higher than that in previously reported studies for the general population but it was close to the incidence reported in Malmø, Sweden. © 2011 John Wiley & Sons A/S.

  5. Generalized dynamics of moving dislocations in quasicrystals

    International Nuclear Information System (INIS)

    Agiasofitou, Eleni; Lazar, Markus; Kirchner, Helmut

    2010-01-01

    A theoretical framework for dislocation dynamics in quasicrystals is provided according to the continuum theory of dislocations. Firstly, we present the fundamental theory for moving dislocations in quasicrystals giving the dislocation density tensors and introducing the dislocation current tensors for the phonon and phason fields, including the Bianchi identities. Next, we give the equations of motion for the incompatible elastodynamics as well as for the incompatible elasto-hydrodynamics of quasicrystals. We continue with the derivation of the balance law of pseudomomentum thereby obtaining the generalized forms of the Eshelby stress tensor, the pseudomomentum vector, the dynamical Peach-Koehler force density and the Cherepanov force density for quasicrystals. The form of the dynamical Peach-Koehler force for a straight dislocation is obtained as well. Moreover, we deduce the balance law of energy that gives rise to the generalized forms of the field intensity vector and the elastic power density of quasicrystals. The above balance laws are produced for both models. The differences between the two models and their consequences are revealed. The influences of the phason fields as well as of the dynamical terms are also discussed.

  6. Creep Deformation by Dislocation Movement in Waspaloy.

    Science.gov (United States)

    Whittaker, Mark; Harrison, Will; Deen, Christopher; Rae, Cathie; Williams, Steve

    2017-01-12

    Creep tests of the polycrystalline nickel alloy Waspaloy have been conducted at Swansea University, for varying stress conditions at 700 °C. Investigation through use of Transmission Electron Microscopy at Cambridge University has examined the dislocation networks formed under these conditions, with particular attention paid to comparing tests performed above and below the yield stress. This paper highlights how the dislocation structures vary throughout creep and proposes a dislocation mechanism theory for creep in Waspaloy. Activation energies are calculated through approaches developed in the use of the recently formulated Wilshire Equations, and are found to differ above and below the yield stress. Low activation energies are found to be related to dislocation interaction with γ' precipitates below the yield stress. However, significantly increased dislocation densities at stresses above yield cause an increase in the activation energy values as forest hardening becomes the primary mechanism controlling dislocation movement. It is proposed that the activation energy change is related to the stress increment provided by work hardening, as can be observed from Ti, Ni and steel results.

  7. Representation of dislocation cores using Nye tensor distributions

    International Nuclear Information System (INIS)

    Hartley, Craig S.; Mishin, Y.

    2005-01-01

    This paper demonstrates how the cores of atomistically simulated dislocations in Cu and Al can be represented by a distribution of infinitesimal dislocations described by appropriate components of the Nye tensor. Components calculated from atomic positions in the dislocated crystal are displayed as contour plots on the plane normal to the dislocation line. The method provides an accurate and instructive means for characterizing dislocation core structures and calculating the total Burgers vector

  8. Rehabilitation of a Patient with an Intra Oral Prosthesis and an Extra Oral Orbital Prosthesis Retained with Magnets

    OpenAIRE

    Pattanaik, Seema; Wadkar, Aarti P.

    2011-01-01

    This clinical case report deals with a rehabilitation of a patient with an extensive maxillary and orbital defect using an intra oral prosthesis obturating the maxillary defect and extra oral orbital prosthesis retained with rare-earth magnets for secondary retention; primary retention was derived by snug fit of the prosthesis to underlying and adjacent tissues. The rehabilitation resulted in improved function, esthetics and comfort to the patient thus enabling him to lead a normal life.

  9. Lower limb strength and flexibility in athletes with and without patellar tendinopathy.

    Science.gov (United States)

    Scattone Silva, Rodrigo; Nakagawa, Theresa H; Ferreira, Ana Luisa G; Garcia, Luccas C; Santos, José E M; Serrão, Fábio V

    2016-07-01

    To compare the hip, knee and ankle torques, as well as knee and ankle flexibility between athletes with patellar tendinopathy and asymptomatic controls. Cross-sectional study. Laboratory setting. Fourteen male volleyball, basketball or handball athletes, divided into 2 groups, patellar tendinopathy group (TG; n = 7) and asymptomatic control group (CG; n = 7). Hip, knee and ankle isometric torques were measured with a handheld dynamometer. Weight-bearing ankle dorsiflexion, hamstring and quadriceps flexibility were measured with a gravity inclinometer. The TG had 27% lower hip extensor torque when compared to the CG (P = 0.031), with no group differences in knee and ankle torques (P > 0.05). Also, the TG had smaller weight-bearing ankle dorsiflexion (P = 0.038) and hamstring flexibility (P = 0.006) when compared to the CG. Regarding quadriceps flexibility, no group differences were found (P = 0.828). Strength and flexibility deficits might contribute to a greater overload on the knee extensor mechanism, possibly contributing to the origin/perpetuation of patellar tendinopathy. Interventions aiming at increasing hip extensors strength as well as ankle and knee flexibility might be important for the rehabilitation of athletes with patellar tendinopathy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Corticosteroid injections, eccentric decline squat training and heavy slow resistance training in patellar tendinopathy

    DEFF Research Database (Denmark)

    Kongsgaard, M.; Kovanen, V.; Aagaard, P.

    2009-01-01

    A randomized-controlled single-blind trial was conducted to investigate the clinical, structural and functional effects of peritendinous corticosteroid injections (CORT), eccentric decline squat training (ECC) and heavy slow resistance training (HSR) in patellar tendinopathy. Thirty-nine male...

  11. Risk factors for patellar tendinopathy in basketball and volleyball players : A cross-sectional study

    NARCIS (Netherlands)

    Van der Worp, H.; Van Ark, M.; Zwerver, J.; Van den Akker-Scheek, I.

    2012-01-01

    Patellar tendinopathy (PT) has a multifactorial etiology, and many possible risk factors have been described in the literature. The findings are conflicting, though, and most research has been conducted on elite athletes. The aim of the current study is to determine the risk factors for PT in a

  12. Metabolic and cytoprotective effects of in vivo peri-patellar hyaluronic acid injections in cultured tenocytes.

    Science.gov (United States)

    Salamanna, F; Frizziero, A; Pagani, S; Giavaresi, G; Curzi, D; Falcieri, E; Marini, M; Abruzzo, P M; Martini, L; Fini, M

    2015-02-01

    The purpose of this study was to investigate tenocyte mechanobiology after sudden-detraining and to examine the hypothesis that repeated peri-patellar injections of hyaluronic acid (HA) on detrained patellar tendon (PT) may reduce and limit detrained-associated damage in tenocytes. Twenty-four male Sprague-Dawley rats were divided into three groups: Untrained, Trained and Detrained. In the Detrained rats, the left tendon was untreated while the right tendon received repeated peri-patellar injections of either HA or saline (NaCl). Tenocyte morphology, metabolism and synthesis of C-terminal-propeptide of type I collagen, collagen-III, fibronectin, aggrecan, tenascin-c, interleukin-1β, matrix-metalloproteinase-1 and-3 were evaluated after 1, 3, 7 and 10 days of culture. Transmission-electronic-microscopy showed a significant increase in mitochondria and rough endoplasmic reticulum in cultured tenocytes from Detrained-HA with respect to those from Detrained-NaCl. Additionally, Detrained-HA cultures showed a significantly higher proliferation rate and viability, and increased synthesis of C-terminal-Propeptide of type I collagen, fibronectin, aggrecan, tenascin-c and matrix-metalloproteinase-3 with respect to Detrained-NaCl ones, whereas synthesis of matrix-metalloproteinase-1 and interleukin-1β was decreased. Our study demonstrates that discontinuing training activity in the short-term alters tenocyte synthetic and metabolic activity and that repeated peri-patellar infiltrations of HA during detraining allow the maintenance of tenocyte anabolic activity.

  13. Pain assessment in patellar tendinopathy using pain pressure threshold algometry: : An observational study

    NARCIS (Netherlands)

    Kregel, Jeroen; van Wilgen, Cornelis Paul; Zwerver, Johannes

    ObjectiveAssessing pain in patellar tendinopathy (PT) is difficult to perform in a standardized way. With this study, we measured pain in athletes with PT by means of pain pressure threshold (PPT) algometry in a standardized manner. Subsequently, the goal of this study is to determine normative

  14. The impact of patellar tendinopathy on sports and work performance in active athletes

    NARCIS (Netherlands)

    De Vries, Astrid J; Koolhaas, Wendy; Zwerver, Johannes; Diercks, Ron L.; Nieuwenhuis, Kari; Van Der Worp, Henk; Brouwer, Sandra; Van Den Akker-Scheek, Inge

    2017-01-01

    Greater insight into sports and work performance of athletes with patellar tendinopathy (PT) will help establish the severity of this common overuse injury. Primary aim of this study is to investigate the impact of PT on sports and work performance. Seventy seven active athletes with PT (50 males;

  15. Treatment of transverse patellar fractures : a comparison between metallic and non-metallic implants

    NARCIS (Netherlands)

    Heusinkveld, M.H.G.; Hamer, den A.; Traa, W.A.; Oomen, P.J.A.; Maffulli, N.

    2013-01-01

    Introduction: Several methods of transverse patellar fixation have been described. This study compares the clinical outcome and the occurrence of complications of various fixation methods. Sources of data: The databases PubMed, Web of Science, Science Direct, Google Scholar and Google were searched.

  16. Impact of Patellar Tendinopathy on Knee Proprioception: A Cross-Sectional Study.

    Science.gov (United States)

    Torres, Rui; Ferreira, João; Silva, Diogo; Rodrigues, Elisa; Bessa, Isabel M; Ribeiro, Fernando

    2017-01-01

    To determine whether high-level athletes with patellar tendinopathy have diminished knee proprioceptive acuity. Cross-sectional study. University research laboratory (institutional). Twenty-one basketball and volleyball players with patellar tendinopathy (13 men and 8 women; mean age 24.5 ± 3.6; body mass index = 22.5 ± 2.0 kg/m) and an equal number of athletes without symptoms of patellar tendinopathy injury were included in this study. Participants underwent knee proprioception assessments on a single day. Furthermore, age, sex, height, weight, VISA-P (Victorian Institute of Sport Assessment) questionnaire sports participation, medical history, knee injuries, previous treatment, and medication were obtained. Knee proprioception was evaluated by assessing sense of resistance, using a weight discrimination protocol, and joint position sense (JPS). No significant differences were observed in JPS at 30 and 60 degrees of knee flexion between groups (P = 0.165 and 0.481, respectively). In regard to the ability to discriminate weight, significant differences between the 2 groups were found with the tendinopathy group showing a higher percentage of error (P = 0.009), namely when the set of incremental weights varied by 10% from the standard weight. Athletes with patellar tendinopathy have a diminished perception of force signals required for weight discrimination, whereas JPS remains unaffected in these athletes.

  17. Medium-term evaluation of total knee arthroplasty without patellar replacement

    Directory of Open Access Journals (Sweden)

    José Wanderley Vasconcelos

    2013-06-01

    Full Text Available OBJECTIVE: To mid-term evaluate patients who were submitted to total knee arthroplasty without patellar resurfacing. METHODS: It was realized a retrospective cross-sectional study of patients who were submitted to total knee arthroplasty without patellar resurfacing. In all patients clinical examination was done based on the protocol of the Knee Society Scoring System, which assessed pain, range of motion, stability, contraction, knee alignment and function, and radiological evaluation. RESULTS: A total of 36 patients were evaluated. Of these, 07 were operated only on left knee, 12 only on right knee and 17 were operated bilaterally, totaling 53 knees. Ages ranged from 26 to 84 years. Of the 53 knees evaluated, 33 (62.26% had no pain. The maximum flexion range of motion averaged 104.7°. No knee had difficulty in active extension. As to the alignment for anatomical axis twelve knees (22.64% showed deviation between 0° and 4° varus. Thirty-nine (75.49% knees showed pace without restriction and the femorotibial angle ranged between 3° varus and 13° valgus with an average of 5° valgus. The patellar index ranged from 0.2 to 1.1. CONCLUSION: Total knee arthroplasty whitout patellar resurfacing provides good results in mid-term evaluation.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Risk factors for patellar tendinopathy : A systematic review of the literature

    NARCIS (Netherlands)

    van der Worp, Henk; van Ark, Mathijs; Roerink, Saskia; Pepping, Gert-Jan; van den Akker-Scheek, Inge; Zwerver, Johannes

    Patellar tendinopathy (PT) is an injury with a high prevalence in sports. Knowledge of risk factors is essential for developing preventive measures and rehabilitation programmes. However, risk factors associated with PT have not yet been systematically studied. This review was undertaken to identify

  20. Evolution of the patellar sesamoid bone in mammals

    Directory of Open Access Journals (Sweden)

    Mark E. Samuels

    2017-03-01

    Full Text Available The patella is a sesamoid bone located in the major extensor tendon of the knee joint, in the hindlimb of many tetrapods. Although numerous aspects of knee morphology are ancient and conserved among most tetrapods, the evolutionary occurrence of an ossified patella is highly variable. Among extant (crown clade groups it is found in most birds, most lizards, the monotreme mammals and almost all placental mammals, but it is absent in most marsupial mammals as well as many reptiles. Here, we integrate data from the literature and first-hand studies of fossil and recent skeletal remains to reconstruct the evolution of the mammalian patella. We infer that bony patellae most likely evolved between four and six times in crown group Mammalia: in monotremes, in the extinct multituberculates, in one or more stem-mammal genera outside of therian or eutherian mammals and up to three times in therian mammals. Furthermore, an ossified patella was lost several times in mammals, not including those with absent hindlimbs: once or more in marsupials (with some re-acquisition and at least once in bats. Our inferences about patellar evolution in mammals are reciprocally informed by the existence of several human genetic conditions in which the patella is either absent or severely reduced. Clearly, development of the patella is under close genomic control, although its responsiveness to its mechanical environment is also important (and perhaps variable among taxa. Where a bony patella is present it plays an important role in hindlimb function, especially in resisting gravity by providing an enhanced lever system for the knee joint. Yet the evolutionary origins, persistence and modifications of a patella in diverse groups with widely varying habits and habitats—from digging to running to aquatic, small or large body sizes, bipeds or quadrupeds—remain complex and perplexing, impeding a conclusive synthesis of form, function, development and genetics across

  1. Structural and in vivo mechanical characterization of canine patellar cartilage: a closed chondromalacia patellae model.

    Science.gov (United States)

    LaBerge, M; Audet, J; Drouin, G; Rivard, C H

    1993-01-01

    The purpose of this project was to study the relationship between the structure of the patellar cartilage and its response to static compressive loading with a closed chondromalacia patellae model. An animal model was used to induce degeneration of the patella that was monitored quantitatively and qualitatively as a function of time. Ten adult mongrel dogs had their left patellofemoral groove replaced by a customized metallic implant covered with a thin film of polyethylene for periods of 3 months (five dogs) and 6 months (five dogs). An indenter was designed to perform mechanical indentation testing on the patellar cartilage in situ. The animals were anesthetized and the response of patellar cartilage to a static compressive load of 4.5 MPa was monitored for 20 min and its relaxation after load removal for 20 min. Indentation tests were performed every 3 months of the implantation period. At the end of the implantation period, the patellae were processed for histology, and sections were stained with Safranin-O indicative of the proteoglycans content. Macroscopically, no apparent degeneration or fibrillation of the patellar surfaces was observed after 3 or 6 months of implantation. However, the patellar surface showed a change in coloration after 6 months. A 17 +/- 3% and 37 +/- 8% deformation of the cartilage were calculated for the 3-month and 6-month specimens, respectively. Histologically, a progressive loss of proteoglycans was observed in the matrix as a function of implantation time. These results indicated that an increase in cartilage compliance is associated with an intrinsic remodeling of the cartilage matrix and that these changes might occur without external signs of degeneration and can be quantified.

  2. Patellar Tendon Repair Augmentation With a Knotless Suture Anchor Internal Brace: A Biomechanical Cadaveric Study.

    Science.gov (United States)

    Rothfeld, Alex; Pawlak, Amanda; Liebler, Stephenie A H; Morris, Michael; Paci, James M

    2018-04-01

    Patellar tendon repair with braided polyethylene suture alone is subject to knot slippage and failure. Several techniques to augment the primary repair have been described. Purpose/Hypothesis: The purpose was to evaluate a novel patellar tendon repair technique augmented with a knotless suture anchor internal brace with suture tape (SAIB). The hypothesis was that this technique would be biomechanically superior to a nonaugmented repair and equivalent to a standard augmentation with an 18-gauge steel wire. Controlled laboratory study. Midsubstance patellar tendon tears were created in 32 human cadaveric knees. Two comparison groups were created. Group 1 compared #2 supersuture repair without augmentation to #2 supersuture repair with SAIB augmentation. Group 2 compared #2 supersuture repair with an 18-gauge stainless steel cerclage wire augmentation to #2 supersuture repair with SAIB augmentation. The specimens were potted and biomechanically loaded on a materials testing machine. Yield load, maximum load, mode of failure, plastic displacement, elastic displacement, and total displacement were calculated for each sample. Standard statistical analysis was performed. There was a statistically significant increase in the mean ± SD yield load and maximum load in the SAIB augmentation group compared with supersuture alone (mean yield load: 646 ± 202 N vs 229 ± 60 N; mean maximum load: 868 ± 162 N vs 365 ± 54 N; P augmented repairs (mean yield load: 495 ± 213 N vs 566 ± 172 N; P = .476; mean maximum load: 737 ± 210 N vs 697 ± 130 N; P = .721). Patellar tendon repair augmented with SAIB is biomechanically superior to repair without augmentation and is equivalent to repair with augmentation with an 18-gauge stainless steel cerclage wire. This novel patellar tendon repair augmentation is equivalent to standard 18-gauge wire augmentation at time zero. It does not require a second surgery for removal, and it is biomechanically superior to primary repair alone.

  3. The Relationship of Static Tibial Tubercle-Trochlear Groove Measurement and Dynamic Patellar Tracking.

    Science.gov (United States)

    Carlson, Victor R; Sheehan, Frances T; Shen, Aricia; Yao, Lawrence; Jackson, Jennifer N; Boden, Barry P

    2017-07-01

    The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown. To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella. Cohort study (Diagnosis); Level of evidence, 2. The static TT-TG distance was measured at full extension for 70 skeletally mature subjects with (n = 32) and without (n = 38) patellofemoral pain. The dynamic patellar tracking patterns were assessed from approximately 45° to 0° of knee flexion by use of dynamic cine-phase contrast magnetic resonance imaging. For each subject, the value of dynamic lateral tracking corresponding to the exact knee angle measured in the static images for that subject was identified. Linear regression analysis determined the predictive ability of static TT-TG distance for dynamic patellar lateral displacement for each cohort. The static TT-TG distance measured with the knee in full extension cannot accurately predict dynamic lateral displacement of the patella. There was weak predictive ability among subjects with patellofemoral pain ( r 2 = 0.18, P = .02) and no predictive capability among controls. Among subjects with patellofemoral pain and static TT-TG distances 15 mm or more, 8 of 13 subjects (62%) demonstrated neutral or medial patellar tracking patterns. The static TT-TG distance cannot accurately predict dynamic lateral displacement of the patella. A large percentage of patients with patellofemoral pain and pathologically large TT-TG distances may have neutral to medial maltracking patterns.

  4. Diagnostic Accuracy of a Self-Report Measure of Patellar Tendinopathy in Youth Basketball.

    Science.gov (United States)

    Owoeye, Oluwatoyosi B A; Wiley, J Preston; Walker, Richard E A; Palacios-Derflingher, Luz; Emery, Carolyn A

    2018-04-27

    Study Design Prospective diagnostic accuracy validation study. Background Engaging clinicians for diagnosis of patellar tendinopathy in large surveillance studies is often impracticable. A self-report measure, the Oslo Sports Research Trauma Centre patellar tendinopathy (OSTRC-P) Questionnaire, an adaptation of the OSTRC Questionnaire may provide a viable alternative. Objectives To evaluate the diagnostic accuracy of the OSTRC-P Questionnaire in detecting patellar tendinopathy in youth basketball players when compared to clinical evaluation. Methods Following the Standards for Reporting of Diagnostic Accuracy Studies guidelines, 208 youth basketball players (aged 13-18 years) were recruited. Participants completed the OSTRC-P Questionnaire (index test) prior to a clinical evaluation (reference standard) by a physiotherapist blinded to OSTRC-P Questionnaire results. Sensitivity, specificity, predictive values (PVs), likelihood ratios (LRs) and posttest probabilities were calculated. Linear regression was used to examine the association between OSTRC-P Questionnaire severity score and patellar tendinopathy severity rating during single leg decline squat (SLDS). Results The final analysis included 169 players. The OSTRC-P Questionnaire had a sensitivity of 79% (95%CI: 65%, 90%), specificity of 98% (95%CI: 94%, 100%), positive PV of 95%, negative PV of 92%, positive LR of 48 and negative LR of 0.21. The posttest probabilities were 95% and 8% given positive and negative results, respectively. A positive association was found between OSTRC-P Questionnaire and SLDS rating [(β = .08 (95%CI: .03, .12) (p = .001)]. Conclusions The OSTRC-P Questionnaire is an acceptable alternative to clinical evaluation for self-reporting patellar tendinopathy and grading its severity in settings involving youth basketball players. Level of Evidence Diagnosis, level 1b. J Orthop Sports Phys Ther, Epub 27 Apr 2018. doi:10.2519/jospt.2018.8088.

  5. Dislocation Dynamics in Al-Li Alloys. Mean Jump Distance and Activation Length of Moving Dislocations

    NARCIS (Netherlands)

    Hosson, J.Th.M. De; Huis in 't Veld, A.; Tamler, H.; Kanert, O.

    1984-01-01

    Pulsed nuclear magnetic resonance proved to be a complementary new technique for the study of moving dislocations in Al-Li alloys. The NMR technique, in combination with transmission electron microscopy and strain-rate change experiments have been applied to study dislocation motion in Al-2.2 wt% Li

  6. The impact of physically demanding work of basketball and volleyball players on the risk for patellar tendinopathy and on work limitations.

    Science.gov (United States)

    van der Worp, H; Zwerver, J; Kuijer, P P F M; Frings-Dresen, M H W; van den Akker-Scheek, I

    2011-01-01

    Patellar tendinopathy is a common injury in jumping athletes. Little is known about work-related etiological factors for patellar tendinopathy and related work limitations. The aim of this study was to identify work-related etiological factors for patellar tendinopathy and to determine the relation between patellar tendinopathy and work limitations. Basketball and volleyball players between 18 and 35 years were invited to complete an online-questionnaire concerning knee complaints, etiological risk factors for patellar tendinopathy and related work limitations. A total of 1505 subjects were included in the analysis. Risk factors for patellar tendinopathy were gender and heavy physically demanding work. The odds for having patellar tendinopathy were significantly higher for heavy physically demanding occupations compared to mentally demanding occupations. 30% of subjects with patellar tendinopathy with a physically demanding job reported to be impaired in their work and 17% reported to be less productive. Basketball and volleyball players with heavy physically demanding work seem to have an increased risk for developing patellar tendinopathy. This finding has important clinical relevance in the treatment of this injury. Working activities should be adjusted in order to reduce the total load on the patellar tendon and help prevention and recovery.

  7. Molecular dynamics simulation of dislocation intersections in aluminum

    International Nuclear Information System (INIS)

    Li, M.; Chu, W.Y.; Qian, C.F.; Gao, K.W.; Qiao, L.J.

    2003-01-01

    The molecular dynamics method is used to simulate dislocation intersection in aluminum containing 1.6x10 6 atoms using embedded atom method (EAM) potential. The results show that after intersection between two right-hand screw dislocations of opposite sign there are an extended jog corresponding to a row of 1/3 vacancies in the intersected dislocation, and a trail of vacancies behind the moving dislocation. After intersection between screw dislocations of same sign, there are an extended jog corresponding to a row of 1/3 interstitials in the intersected dislocation, and a trail of interstitials behind the moving dislocation. After intersection between screw and edge dislocations with different Burgers vector, there are a constriction corresponding to one 1/3 vacancy in the edge dislocation, and no point-defects behind the screw dislocation. When a moving screw dislocation intersects an edge dislocation with the same Burgers vector, the point of intersection will split into two constrictions corresponding to one 1/3 vacancy and 1/3 interstitial, respectively. The moving screw dislocation can pass the edge dislocation only after the two constrictions, which can move along the line of intersection of the two slip planes, meet and annihilate

  8. Fabrication of custom made ocular prosthesis with three different ...

    African Journals Online (AJOL)

    Loss of eye has a bad effect on the psychology of the patient. Eye prosthesis is fabricated to regain the patient's confidence by meticulous replacement of the missing eye. Immediate fitting of an anophthalmic socket with an artificial eye may not always be possible, and a delayed prosthesis delivery may result in settling and ...

  9. Treatment of femoral neck fracture by Moore Prosthesis in Cotonou ...

    African Journals Online (AJOL)

    Treatment of femoral neck fracture by Moore Prosthesis in Cotonou. AHM Akue, M Lawson, S Madougou, R Zannou, J Padonou. Abstract. Keywords: Benin; hip; Moore prosthesis; results. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  10. A direct bonded fixed partial dental prosthesis: A clinical report

    OpenAIRE

    Tanoue, Naomi; Tanaka, Takuo

    2015-01-01

    A direct bonded fixed partial dental prosthesis, with a composite resin denture tooth as a pontic, a tri-n-butylborane initiated adhesive resin, and screw posts for reinforcement, was still functioning after an observation period of 20 years. The prosthesis was found to be reliable for long-term clinical use when chemically and mechanically reinforced.

  11. 21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).

    Science.gov (United States)

    2010-04-01

    ... implant). 872.3970 Section 872.3970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis...

  12. Analysis of the mechanical behavior of the Nijdam voice prosthesis

    NARCIS (Netherlands)

    Verkerke, GJ; deVries, MP; Schutte, HK; vandenHoogen, FJA; Rakhorst, G

    1997-01-01

    The valveless Nijdam prosthesis is a new voice prosthesis for laryngectomized patients using tracheoesophageal speech. An ''umbrella-like hat'' covers the esophageal side of the tracheoesophageal fistula and is deformed during speech by air pressure. To decrease pressure loss during speech, a good

  13. Patient satisfaction with maxillofacial prosthesis. Literature review.

    Science.gov (United States)

    Goiato, Marcelo Coelho; Pesqueira, Aldiéris Alves; Ramos da Silva, Cristina; Gennari Filho, Humberto; Micheline Dos Santos, Daniela

    2009-02-01

    Obturators and facial prostheses are important not only in rehabilitation and aesthetics, but also in patient re-socialisation. The level of reintegration is directly related to the degree of satisfaction with rehabilitation. So, the maxillofacial prosthetics must provide patient satisfaction during treatment. This study aimed to search information in database and conduct a literature review on patient satisfaction with maxillofacial prosthesis. The problems experienced by these patients may decrease when specialists keep the patient on regular inspection. Rehabilitation through alloplasty or prosthetic restoration provides satisfactory conditions in aesthetics and well-being and reinstates individuals in familial and social environment.

  14. Effectiveness of Shockwave Treatment Combined With Eccentric Training for Patellar Tendinopathy : A Double-Blinded Randomized Study

    NARCIS (Netherlands)

    Thijs, Karin M; Zwerver, Johannes; Backx, Frank J G; Steeneken, Victor; Rayer, Stephan; Groenenboom, Petra; Moen, Maarten H

    OBJECTIVE: To evaluate the effectiveness of a combined treatment of focused shockwave therapy (ESWT) and eccentric training compared with sham-shockwave therapy (placebo) and eccentric training in participants with patellar tendinopathy (PT) after 24 weeks. DESIGN: Randomized controlled trial.

  15. Effectiveness of Shockwave Treatment Combined With Eccentric Training for Patellar Tendinopathy : A Double-Blinded Randomized Study

    NARCIS (Netherlands)

    Thijs, Karin M.; Zwerver, Johannes; Backx, Frank J. G.; Steeneken, Victor; Rayer, Stephan; Groenenboom, Petra; Moen, Maarten H.

    2017-01-01

    OBJECTIVE: To evaluate the effectiveness of a combined treatment of focused shockwave therapy (ESWT) and eccentric training compared with sham-shockwave therapy (placebo) and eccentric training in participants with patellar tendinopathy (PT) after 24 weeks. DESIGN: Randomized controlled trial.

  16. Penile Corporeal Reconstruction during Difficult Placement of a Penile Prosthesis

    Directory of Open Access Journals (Sweden)

    Viet Q. Tran

    2008-01-01

    Full Text Available For some patients with impotence and concomitant severe tunical/corporeal tissue fibrosis, insertion of a penile prosthesis is the only option to restore erectile function. Closing the tunica over an inflatable penile prosthesis in these patients can be challenging. We review our previous study which included 15 patients with severe corporeal or tunical fibrosis who underwent corporeal reconstruction with autologous rectus fascia to allow placement of an inflatable penile prosthesis. At a mean follow-up of 18 months (range 12 to 64, all patients had a prosthesis that was functioning properly without evidence of separation, herniation, or erosion of the graft. Sexual activity resumed at a mean time of 9 weeks (range 8 to 10. There were no adverse events related to the graft or its harvest. Use of rectus fascia graft for coverage of a tunical defect during a difficult penile prosthesis placement is surgically feasible, safe, and efficacious.

  17. Amputation and prosthesis implantation shape body and peripersonal space representations.

    Science.gov (United States)

    Canzoneri, Elisa; Marzolla, Marilena; Amoresano, Amedeo; Verni, Gennaro; Serino, Andrea

    2013-10-03

    Little is known about whether and how multimodal representations of the body (BRs) and of the space around the body (Peripersonal Space, PPS) adapt to amputation and prosthesis implantation. In order to investigate this issue, we tested BR in a group of upper limb amputees by means of a tactile distance perception task and PPS by means of an audio-tactile interaction task. Subjects performed the tasks with stimulation either on the healthy limb or the stump of the amputated limb, while wearing or not wearing their prosthesis. When patients performed the tasks on the amputated limb, without the prosthesis, the perception of arm length shrank, with a concurrent shift of PPS boundaries towards the stump. Conversely, wearing the prosthesis increased the perceived length of the stump and extended the PPS boundaries so as to include the prosthetic hand, such that the prosthesis partially replaced the missing limb.

  18. High dislocation density of tin induced by electric current

    International Nuclear Information System (INIS)

    Liao, Yi-Han; Liang, Chien-Lung; Lin, Kwang-Lung; Wu, Albert T.

    2015-01-01

    A dislocation density of as high as 10 17 /m 2 in a tin strip, as revealed by high resolution transmission electron microscope, was induced by current stressing at 6.5 x 10 3 A/ cm 2 . The dislocations exist in terms of dislocation line, dislocation loop, and dislocation aggregates. Electron Backscattered Diffraction images reflect that the high dislocation density induced the formation of low deflection angle subgrains, high deflection angle Widmanstätten grains, and recrystallization. The recrystallization gave rise to grain refining

  19. Patellar tendinopathy in young elite soccer- clinical and sonographical analysis of a German elite soccer academy.

    Science.gov (United States)

    Bode, Gerrit; Hammer, Thorsten; Karvouniaris, N; Feucht, M J; Konstantinidis, L; Südkamp, N P; Hirschmüller, A

    2017-08-08

    The prevalence of patellar tendinopathy is elevated in elite soccer compared to less explosive sports. While the burden of training hours and load is comparably high in youth elite players (age soccer academy. One hundred nineteen male youth soccer players (age 15,97 ± 2,24 years, height 174, 60 ± 10,16 cm, BMI 21, 24 ± 2,65) of the U-13 to U-23 teams were part of the study. Data acquisition included sport specific parameters such as footwear, amount of training hours, leg dominance, history of tendon pathologies, and clinical examination for palpatory pain, indurations, muscular circumference, and range of motion. Subjective complaints were measured with the Victorian Institute of Sport Assessment Patellar (VISA-P) Score. Furthermore, sonographical examinations (Aplio SSA-770A/80; Toshiba, Tokyo, Japan) with 12-MHz multifrequency linear transducers (8-14 MHz) of both patellar tendons were performed with special emphasis on hyper- and hypo echogenic areas, diameter and neovascularization. The prevalence of patellar tendinopathies was 13.4%. Seventy-five percent of the players complained of pain of their dominant leg with onset of pain at training in 87.5%. The injured players showed a medium amount of 10.34 ± 3.85 training hours and a medium duration of symptoms of 11.94 ± 18.75 weeks. Two thirds of players with patellar tendinopathy were at the age of 15-17 (Odds ratio 1.89) while no differences between players of the national or regional league were observed. In case of patellar tendinopathy, VISA-P was significantly lower in comparison to healthy players (mean ± SD 76.80 ± 28.56 points vs. 95.85 ± 10.37). The clinical examination revealed local pain at the distal patella, pain at stretching, and thickening of the patellar tendon (p = 0.02). The mean tendon diameter measured 2 cm distally to the patella was 4.10 ± 0.68 mm with a significantly increased diameter of 0.15 mm in case of an underlying tendinopathy (p = 0.00). The

  20. Difficult factors in Management of Impacted Dental Prosthesis in Esophagus

    Directory of Open Access Journals (Sweden)

    Efiaty A. Soepardi

    2005-03-01

    Full Text Available A dental prosthesis which ingested and impacted in esophagus, is an emergency case and life threatening, so require immediate esophagoscopy intervention for removing. The objective of this study is to assess some factors can caused dtfficulties in diagnosing and treating the ingested and impacted dental prosthesis in the esophagus and their complications. This retrospective study analyzed patient’s chart whose underwent esophagoscopy for removing the impacted dental prosthesis in Dr. Cipto Mangunkusumo General Hospital, Jakarta, Indonesia during a period between January 1997 and December 2003. Neck-chest X-ray and esophagoscopy were performed in all patients to identify the existence of the dental prosthesis as a diagnostic and treatment procedure. The length of time for removing the dental prosthesis was recorded and stated as a less difficult esophagoscopy when it takes time less than 60 minutes and as a difficult  esophagoscopy takes 60 minutes or longer. Some risk difficulties factors were statistically analyzed. There were 53 patients of ingested dental prosthesis in esophagus. Only 51 cases were analyzed According to the length of time for removing the dental prosthesis by esophagoscopy, 22 patients were recorded as less difficult cases and 29 patients as difficult cases. Two cases among the cases needed cervicotomy after unsuccessful esophagoscopy removal. The difficulties to diagnose an impacted dental prosthesis in the esophagus caused by unreliable clinical history, unclear signs and symptoms, unable to be detected by X-ray and was not found during esophagoscopy. The difficulties in treating due to mucosal laceration, edema, bleeding, failure of the first extraction and conformity with the size and shape, the wire outside the dental prosthesis and the length of time stayed in the esophagus. (Med J Indones 2005; 14: 33-6Keywords: ingested dental prosthesis, radioluscent foreign body, length of time of esophagoscopy

  1. A soft patellar tendon on ultrasound elastography is associated with pain and functional deficit in volleyball players.

    Science.gov (United States)

    Ooi, Chin Chin; Richards, Paula J; Maffulli, Nicola; Ede, David; Schneider, Michal E; Connell, David; Morrissey, Dylan; Malliaras, Peter

    2016-05-01

    To investigate the diagnostic performance of grey scale Ultrasound (US), power Doppler (PD) and US elastography for diagnosing painful patellar tendinopathy, and to establish their relationship with Victorian Institute of Sport Assessment-Patella (VISA-P) scores in a group of volleyball players with and without symptoms of patellar tendinopathy. Cross-sectional study. Thirty-five volleyball players (70 patellar tendons) were recruited during a national university volleyball competition. Players were imaged with conventional US followed by elastography. The clinical findings of painful patellar tendons were used as the reference standard for diagnosing patellar tendinopathy. In addition, all participants completed the VISA-P questionnaires. Of the 70 patellar tendons, 40 (57.1%) were clinically painful. The diagnostic accuracy of grey scale US, PD and elastography were 60%, 50%, 62.9%, respectively, with sensitivity/specificity of 72.5%/43.3%, 12.5%/100%, and 70%/53.3%, respectively. Combined US elastography and grey scale imaging achieved 82.5% sensitivity, 33.3% specificity and 61.4% accuracy while routine combination technique of PD and grey scale imaging revealed 72.5% sensitivity, 43.3% specificity and 60.0% accuracy. Tendons in players categorized as soft on elastography had statistically significantly greater AP thickness (p<0.001) and lower VISA-P scores (p=0.004) than those categorized as hard. There was no significant association between grey scale US abnormalities (hypoechogenicities and/or fusiform swelling) and VISA-P scores (p=0.098). Soft tendon properties depicted by US elastography may be more related to patellar tendon symptoms compared to grey scale US abnormalities. The supplementation of US elastography to conventional US may enhance the sensitivity for diagnosing patellar tendinopathy in routine clinical practice. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. Void growth suppression by dislocation impurity atmospheres

    International Nuclear Information System (INIS)

    Weertman, J.; Green, W.V.

    1976-01-01

    A detailed calculation is given of the effect of an impurity atmosphere on void growth under irradiation damage conditions. Norris has proposed that such an atmosphere can suppress void growth. The hydrostatic stress field of a dislocation that is surrounded by an impurity atmosphere was found and used to calculate the change in the effective radius of a dislocation line as a sink for interstitials and vacancies. The calculation of the impurity concentration in a Cottrell cloud takes into account the change in hydrostatic pressure produced by the presence of the cloud itself. It is found that void growth is eliminated whenever dislocations are surrounded by a condensed atmosphere of either oversized substitutional impurity atoms or interstitial impurity atoms. A condensed atmosphere will form whenever the average impurity concentration is larger than a critical concentration

  3. Femoral head fracture without hip dislocation

    Directory of Open Access Journals (Sweden)

    Aggarwal Aditya K

    2013-10-01

    Full Text Available 【Abstract】Femoral head fractures without dislocation or subluxation are extremely rare injuries. We report a neglected case of isolated comminuted fracture of femoral head without hip dislocation or subluxation of one year duration in a 36-year-old patient who sustained a high en- ergy trauma due to road traffic accident. He presented with painful right hip and inability to bear full weight on right lower limb with Harris hip score of 39. He received cementless total hip replacement. At latest follow-up of 2.3 years, functional outcome was excellent with Harris hip score of 95. Such isolated injuries have been described only once in the literature and have not been classified till now. The purpose of this report is to highlight the extreme rarity, possible mechanism involved and a novel classification system to classify such injuries. Key words: Femur head; Hip dislocation; Classification; Arthroplasty, replacement, hip

  4. Rare Inferior Shoulder Dislocation (Luxatio Erecta

    Directory of Open Access Journals (Sweden)

    Hakan Cift

    2015-01-01

    Full Text Available Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients’ ages were 78, 62, 65, and 76. All patients’ reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitation of range of motion of their shoulder at their last control. Luxatio erecta is seen rarely, and these patients may have neurovascular injury. These patients should be carefully examined and treated by the orthopaedic and traumatology surgeons.

  5. Rare Inferior Shoulder Dislocation (Luxatio Erecta)

    Science.gov (United States)

    Cift, Hakan; Soylemez, Salih; Demiroglu, Murat; Ozkan, Korhan; Ozden, Vahit Emre; Ozkut, Afsar T.

    2015-01-01

    Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients' ages were 78, 62, 65, and 76. All patients' reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitation of range of motion of their shoulder at their last control. Luxatio erecta is seen rarely, and these patients may have neurovascular injury. These patients should be carefully examined and treated by the orthopaedic and traumatology surgeons. PMID:25883820

  6. Dislocation dipole annihilation in diamond and silicon

    Energy Technology Data Exchange (ETDEWEB)

    Rabier, J; Pizzagalli, L, E-mail: jacques.rabier@univ-poitiers.fr [Institut PPRIMME, Departement de Physique et Mecanique des Materiaux - UPR 3346 CNRS, Universite de Poitiers, ENSMA - SP2MI, BP 30179, F-86962 Chasseneuil Futuroscope Cedex (France)

    2011-02-01

    The mechanism of dislocation dipole annihilation has been investigated in C and Si using atomistic calculations with the aim of studying their annihilation by-products. It is shown, in C as well as in Si, that dipole annihilation yields debris that can be depicted as a cluster of vacancies, or alternately by two internal free surfaces. These defects have no strain field and can hardly be seen using usual TEM techniques. This suggests that the brown colouration of diamond could be due to microstructures resulting from deformation mechanisms associated with dipole formation and their annihilation rather than to a climb mechanism and vacancy aggregation. In silicon where a number of dipoles have been evidenced by TEM when dislocation trails are found, such debris could be the missing link responsible for the observation of strong chemical reactivity and electrical activity in the wake of moving dislocations.

  7. High-temperature discrete dislocation plasticity

    Science.gov (United States)

    Keralavarma, S. M.; Benzerga, A. A.

    2015-09-01

    A framework for solving problems of dislocation-mediated plasticity coupled with point-defect diffusion is presented. The dislocations are modeled as line singularities embedded in a linear elastic medium while the point defects are represented by a concentration field as in continuum diffusion theory. Plastic flow arises due to the collective motion of a large number of dislocations. Both conservative (glide) and nonconservative (diffusion-mediated climb) motions are accounted for. Time scale separation is contingent upon the existence of quasi-equilibrium dislocation configurations. A variational principle is used to derive the coupled governing equations for point-defect diffusion and dislocation climb. Superposition is used to obtain the mechanical fields in terms of the infinite-medium discrete dislocation fields and an image field that enforces the boundary conditions while the point-defect concentration is obtained by solving the stress-dependent diffusion equations on the same finite-element grid. Core-level boundary conditions for the concentration field are avoided by invoking an approximate, yet robust kinetic law. Aspects of the formulation are general but its implementation in a simple plane strain model enables the modeling of high-temperature phenomena such as creep, recovery and relaxation in crystalline materials. With emphasis laid on lattice vacancies, the creep response of planar single crystals in simple tension emerges as a natural outcome in the simulations. A large number of boundary-value problem solutions are obtained which depict transitions from diffusional to power-law creep, in keeping with long-standing phenomenological theories of creep. In addition, some unique experimental aspects of creep in small scale specimens are also reproduced in the simulations.

  8. Removable dental prosthesis as periodontal treatment method

    Directory of Open Access Journals (Sweden)

    Aprilia Adenan

    2007-11-01

    Full Text Available The objectives of prostheses are to restore mastication force, improve esthetics and maintain gingival health. The construction and function of prosthesis restoration are mutually interdependent with condition of periodontal tissues. A properly constructed prosthesis is an integral phase of complete treatment of periodontal disease in order to maintain periodontal tissues health. This paper reports case of a man aged 47 years who came to Dental Specialist Clinic in Oral and Dental Hospital Faculty of Dentistry Universitas Padjadjaran with chief complaint of mobility in almost all his teeth and they seems to look longer. The patient has no systemic disease and did not want his teeth to be extracted. Clinical and panoramic radiographic and laboratoris examinations has been done. During treatment, oclusal adjustment and splinting had been done on tooth 33,34,35 and tooth 44,43 also tooth 43,42 splinting with composite. The following treatment was the acrylic removable partial denture for upper jaw while mandible was fitted a frame denture which functioned as a semi permanent splint. One month post treatment, patien felt comfort and the denture was well functioning.

  9. VARIABLE STIFFNESS HAND PROSTHESIS: A SYSTEMATIC REVIEW

    Directory of Open Access Journals (Sweden)

    S. Cecilia Tapia-Siles

    2017-06-01

    Full Text Available Prosthetics is an important field in engineering due to the large number of amputees worldwide and the associated problems such as limited functionality of the state of the art. An important functionality of the human hand is its capability of adjusting the stiffness of the joints depending on the currently performed task. For the development of new technology it is important to understand the limitations of existing resources. As part of our efforts to develop a variable stiffness grasper for developing countries a systematic review was performed covering technology of body powered and myoelectric hand prosthesis. Focus of the review is readiness of prosthetic hands regarding their capability of controlling the stiffness of the end effector. Publications sourced through three different digital libraries were systematically reviewed on the basis of the PRISMA standard. We present a search strategy as well as the PRISMA assessment of the resulting records which covered 321 publications. The records were assessed and the results are presented for the ability of devices to control their joint stiffness. The review indicates that body powered prosthesis are preferred to myoelectric hands due to the reduced cost, the simplicity of use and because of their inherent ability to provide feedback to the user. Stiffness control was identified but has not been fully covered in the current state of the art. In addition we summarise the identified requirements on prosthetic hands as well as related information which can support the development of new prosthetics.

  10. In-vivo patellar tracking in individuals with patellofemoral pain and healthy individuals.

    Science.gov (United States)

    Esfandiarpour, Fateme; Lebrun, Constance M; Dhillon, Sukhvinder; Boulanger, Pierre

    2018-02-28

    Understanding of the exact cause of patellofemoral pain has been limited by methodological challenges to evaluate in-vivo joint motion. This study compared six degree-of-freedom patellar motion during a dynamic lunge task between individuals with patellofemoral pain and healthy individuals. Knee joints of eight females with patellofemoral pain and ten healthy females were imaged using a CT scanner in supine lying position, then by a dual-orthogonal fluoroscope while they performed a lunge. To quantify patellar motion, the three-dimensional models of the knee bones, reconstructed from CT scans, were registered on the fluoroscopy images using the Fluomotion registration software. At full knee extension, the patella was in a significantly laterally tilted (PFP: 11.77° ± 7.58° vs. healthy: 0.86° ± 4.90°; p = 0.002) and superiorly shifted (PFP: 17.49 ± 8.44 mm vs. healthy: 9.47 ± 6.16 mm, p = 0. 033) position in the patellofemoral pain group compared with the healthy group. There were also significant differences between the groups for patellar tilt at 45°, 60°, and 75° of knee flexion, and for superior-inferior shift of the patella at 30° flexion (p ≤ 0.031). In the non-weight-bearing knee extended position, the patella was in a significantly laterally tilted position in the patellofemoral pain group (7.44° ± 6.53°) compared with the healthy group (0.71° ± 4.99°). These findings suggest the critical role of passive and active patellar stabilizers as potential causative factors for patellar malalignment/maltracking. Future studies should investigate the associations between patellar kinematics with joint morphology, muscle activity, and tendon function in a same sample for a thorough understanding of the causes of patellofemoral pain. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  11. Dislocation-cavity interaction in Fe: a comparison between molecular dynamics and dislocation dynamics

    International Nuclear Information System (INIS)

    Hafez Haghighat, S.M.; Schaeublin, R.; Fivel, M.C.

    2007-01-01

    Full text of publication follows: multi-scale modeling, including molecular dynamics (MD) and discrete dislocation dynamics (DDD) methods, appears as a significant tool for the description of plasticity and mechanical properties of materials. This research is on the investigation of the subsequence effects of irradiation on the plasticity of pure Fe and focuses on the interaction of a single dislocation and a spherical cavity, as void or He bubble. Extensive MD simulations of the interaction under imposed strain rate [1, 2] have shown that various temperatures and cavity sizes result in different release stresses depending on dislocation bow out. It appears that a temperature increase and cavity size decrease reduce the cavity strength. MD simulation shows that the elastic field around the cavity is largely anisotropic. This anisotropy may influence the way the dislocation unpins from the cavity. Following the MD simulations, the interaction of a single dislocation and a spherical cavity is now simulated using a DDD discrete dislocation dynamics model. The simulation accounts for the non-Schmidt effect induced by the bcc structure of Fe through local rules derived from MD simulations [3]. The cavity is introduced in the simulation by computing the image forces using a finite element technique. The effective stress applied on the dislocation is then obtained as the superimposition of the applied stress field, the image stress field and the internal stresses. Note that such a model only uses elasticity theory and no core effect of dislocations is taken into account. One of the objectives of this work is to check whether elasticity is responsible of the behaviour observed by MD. Several cases are tested. First an edge dislocation in a (110) plane is pushed against the cavity under a pure shear loading. The local reaction of the dislocations and the cavity are compared to the MD simulations. Then, the case of a screw dislocation is studied. Finally, other loading

  12. Ipsilateral open anterior hip dislocation and open posterior elbow dislocation in an adult

    Directory of Open Access Journals (Sweden)

    Kumar Sunil

    2014-02-01

    Full Text Available 【Abstract】Open anterior dislocation of the hip is a very rare injury, especially in adults. It is a hyperabduction, external rotation and extension injury. Its combination with open posterior dislocation of the elbow has not been described in English language-based medical literature. Primary resuscitation, debridement, urgent reduction of dislocation, and adequate antibiotic support resulted in good clinical outcome in our patient. At 18 months follow-up, no signs of avascular necrosis of the femoral head or infection were observed.

  13. Are unilateral and bilateral patellar tendinopathy distinguished by differences in anthropometry, body composition, or muscle strength in elite female basketball players?

    OpenAIRE

    Gaida, J; Cook, J; Bass, S; Austen, S; Kiss, Z

    2004-01-01

    Background: Overuse injury to the patellar tendon (patellar tendinopathy) is a major reason for interrupted training and competition for elite athletes. In both sexes, the prevalence of unilateral and bilateral tendinopathy has been shown to differ. It has been proposed that bilateral pathology may have a different aetiology from unilateral pathology. Investigation of risk factors that may be unique to unilateral and bilateral patellar tendinopathy in female athletes may reveal insights into ...

  14. The TOPSHOCK study: Effectiveness of radial shockwave therapy compared to focused shockwave therapy for treating patellar tendinopath - design of a randomised controlled trial

    OpenAIRE

    van der Worp, Henk; Zwerver, Johannes; van den Akker-Scheek, Inge; Diercks, Ron L

    2011-01-01

    Abstract Background Patellar tendinopathy is a chronic overuse injury of the patellar tendon that is especially prevalent in people who are involved in jumping activities. Extracorporeal Shockwave Therapy is a relatively new treatment modality for tendinopathies. It seems to be a safe and promising part of the rehabilitation program for patellar tendinopathy. Extracorporeal Shockwave Therapy originally used focused shockwaves. Several years ago a new kind of shockwave therapy was introduced: ...

  15. Combined three-part humeral anterior fracture-dislocation and humeral shaft fracture treated with one-stage long stem shoulder hemiarthroplasty in an active elderly patient

    Directory of Open Access Journals (Sweden)

    Herzberg Guillaume

    2017-01-01

    Full Text Available Introduction: Injuries combining a humeral head fracture-dislocation and a shaft fracture of the ipsilateral humerus are very rare. They should be separated from extended fractures of the humeral head to the shaft [1]. Case report: We present the case of an active 84-year-old man who sustained a three-part fracture-dislocation of the proximal humerus combined with a long spiral humeral middle third diaphyseal fracture, after a ski fall. We were unable to find a similar case in the literature. He was treated with a long stem hemiarthroplasty, associated with screw osteosynthesis of the long spiral shaft fracture. The result after 30 months of follow-up was excellent, with good shoulder range of motion, good bone integration of the prosthesis and uneventful healing of the fracture. Conclusion: This treatment allowed this intrepid elderly patient to recover a normal quality of life, including driving his car and to return to skiing.

  16. Riemann–Cartan Geometry of Nonlinear Dislocation Mechanics

    KAUST Repository

    Yavari, Arash; Goriely, Alain

    2012-01-01

    but vanishing non-metricity. Torsion of the material manifold is identified with the dislocation density tensor of nonlinear dislocation mechanics. Using Cartan's moving frames we construct the material manifold for several examples of bodies with distributed

  17. Dislocation unpinning model of acoustic emission from alkali halide ...

    Indian Academy of Sciences (India)

    The present paper reports the dislocation unpinning model of acoustic emis- sion (AE) from ... Acoustic emission; dislocation; alkali halide crystals; plastic deformation. ..... [5] T Nishimura, A Tahara and T Kolama, Jpn. Metal Inst. 64, 339 (2000).

  18. Impact of hip prosthesis on dose distribution of pelvic radiotherapy

    International Nuclear Information System (INIS)

    Ren Jiangping; Zhang Songfang; Zhu Qibao; Guo Jianxin; Zha Yuanzi

    2011-01-01

    Objective: To study the scattering effect of Co-Cr-Mo hip prosthesis which was high Z material for patients undergoing pelvic irradiation. Methods: The hip prosthesis was set in water phantom (30 cm x 30 cm x 30 cm), determining points were chosen on the entrance side of both 6 MV and 10 MV beams at the distance of 0.5 cm, 1.0 cm, 2.0 cm to the hip prosthesis, and also on the exit side of both 6 MV and 10 MV beams at the distance of 3.0 cm, 5.0 cm, 7.0 cm to the hip prostheses. Dose behind the hip prosthesis at depths of 5.0 cm and 10.0 cm for 6 MV and 10 MV beams are also measured. Results: The dose deviation on the beams' entrance side is between 0 to 5.0%, the backscatter effect was more obviously with the higher energy beam. The dose deviation on the beams' exit side was between 21.6%-30.8%. With the same field size and depth, dose deviation becomes smaller when the beam energy was higher; while with the same energy and depth, dose deviation becomes smaller when the field size was bigger. Dose profiles behind the head of the hip prosthesis indicate obvious attenuation of the beam. Conclusions: Beam arrangements that avoid the prosthesis should be considered first or we should at least reduce the weight of the beam that pass through the prosthesis. (authors)

  19. Orthopaedic measurements with computed radiography: Methodological development, accuracy, and radiation dose with special reference to the weight-bearing lower extremity and the dislocating patella

    Energy Technology Data Exchange (ETDEWEB)

    Sanfridsson, J. [Univ. Hospital, Lund (Sweden). Dept. of Diagnostic Radiology

    2001-03-01

    The overall aim of this study was to develop and evaluate a measurement system for computed radiography and Picture Archiving and Communication Systems, permitting measurements of long distances and angles in and between related images. The developed measurement system, which was based on the QUESTOR Precision Radiography system, was applied to the weight-bearing knee with special reference to the dislocating patella. The QPR system modified for CR fulfilled the criteria for measuring the weight-bearing knee. The special measuring assistance tools that were developed were important for the implementation of CR and PACS, particularly in workstations programmed for musculoskeletal radiology. The energy imparted to the patient was reduced by 98% at the lowest exposure of the CR-system, compared with our conventional analogue method, without loss of diagnostic accuracy. The CR technique creates a possibility, to an extent not previously feasible, to differentiate the exposure parameters (and thus minimise the radiation dose to the patient) by carefully considering the purpose of the examination. A radiographic method for measuring the rotation of the femur and the tibia, and the patellar translation was developed and applied to healthy volunteers. The introduced patellar variables have yielded new insights into the complex sequence of motions between the femur, tibia, and patella. The patients with a dislocating patella were subdivided into one 'clean' group of spontaneous dislocations and one group with various traumas in the history, which thus resulted in two groups with distinct radiographic differences. The Q-angle was decreased in knees that had suffered dislocations, and the traditional surgical treatment with a further reduction of the Q-angle must be challenged. The use of clinical measurements of the Q-angle was not an optimal way to evaluate the mechanical alignment in the patellofemoral joint under physiological conditions. In this study, we have

  20. Coarse-grained elastodynamics of fast moving dislocations

    International Nuclear Information System (INIS)

    Xiong, Liming; Rigelesaiyin, Ji; Chen, Xiang; Xu, Shuozhi; McDowell, David L.; Chen, Youping

    2016-01-01

    The fundamental mechanism of dynamic plasticity in metallic materials subjected to shock loading remains unclear because it is difficult to obtain the precise information of individual fast moving dislocations in metals from the state-of-the-art experiments. In this work, the dynamics of sonic dislocations in anisotropic crystalline materials is explored through a concurrent atomistic-continuum modeling method. We make a first attempt to characterize the complexity of nonuniformly moving dislocations in anisotropic crystals from atomistic to microscale, including the energy intensities as well as the wavelengths of acoustic phonons emitted from sonic dislocations, and the velocity-dependent stress fluctuations around the core of nonuniformly moving dislocations. Instantaneous dislocation velocities and phonon drag effects on the dislocation motions are quantified and analyzed. Mach cones in a V-shaped pattern of the phonon wave-fronts are observed in the wake of the sonic dislocations. Analysis of simulation results based on a wavelet transform show that the faster a dislocation is moving, the longer the emitted phonon wavelength. The dislocation velocity drops dramatically with the occurrence of the interactions between dislocations and phonon waves reflected from the boundaries of specimens. The concurrent atomistic-continuum modeling framework is demonstrated to be the first multiscale method that explicitly treats the strong coupling between the long-range elastic fields away from the dislocation core, the highly nonlinear time-dependent stress field within the core, and the evolutions of the atomic-scale dislocation core structures. As such, it is shown that this method is capable in predicting elastodynamics of dislocations in the presence of inertia effects associated with sonic dislocations in micron-sized anisotropic crystalline materials from the atomic level, which is not directly accessible to the recent elastodynamic discrete dislocation model.

  1. Chondromalacia induced by patellar subluxation: morphological and morphometrical aspects in rabbits.

    Science.gov (United States)

    Sant'Anna, M M S; Apfel, M I R

    2002-01-01

    The purpose of this study was to describe morphologically and quantify the changes of the articular cartilage in chondromalacia, concerning both the chondrocytes and extracellular matrix. Eight rabbits were submitted daily to patellar subluxation, causing chondromalacia after two weeks. The knee fragments obtained were processed by the standard methods. These experimental conditions caused degenerative alterations of the articular cartilage, varying from a slight decrease of proteoglycans, to fibrillations, clefts, and horizontal splitting. The results showed a significantly increase number of chondrocytes (p < 0,000139), although smaller in size (p < 0,000109). The immobilization for 2 weeks and the intermittent passive daily motion afterwards for a period of 2 weeks, was effective to cause patellar chrondomalacia in rabbits.

  2. Tibial Tubercle Osteotomies: a Review of a Treatment for Recurrent Patellar Instability.

    Science.gov (United States)

    Grimm, Nathan L; Lazarides, Alexander L; Amendola, Annunziato

    2018-06-01

    The goal of this review is to provide an overview of current surgical treatment options for tibial tubercle osteotomies as a treatment for recurrent patellofemoral instability. As such we sought to provide the reader with the most current answers to why treatment practices have changed and how this has affected the outcome of surgical treatment for patellar instability. As our understanding of patellofemoral biomechanics have grown, appropriate surgical and non-surgical treatment options have followed suit to address these findings. A clear understanding of the pathomechanics causing the patient's patellar instability is germane to choosing the most appropriate surgical intervention to address this instability. Likewise, understanding the goal of the intervention chosen-e.g., unloading, realignment-is paramount. These surgical techniques may be technically challenging and surgical specialists with experience in these techniques are recommended for optimal outcomes.

  3. Prospective imaging study of asymptomatic patellar tendinopathy in elite junior basketball players.

    Science.gov (United States)

    Cook, J L; Khan, K M; Kiss, Z S; Purdam, C R; Griffiths, L

    2000-07-01

    To evaluate the ability of ultrasonography to predict eventual symptoms in an at-risk population, 52 elite junior basketball players' patellar tendons were studied at baseline and again 16 months later. The group consisted of 10 study tendons (ultrasonographically hypoechoic at baseline) and 42 control tendons (ultrasonographically normal at baseline). By design, all tendons were asymptomatic at baseline. No differences were noted between subjects and controls at baseline for age, height, weight, training hours, and vertical jump. Functional (P patellar tendon changes may resolve, but this is not necessary for an athlete to become asymptomatic. Qualitative or quantitative analysis of baseline ultrasonographic images revealed it was not possible to predict which tendons would develop symptoms or resolve ultrasonographically.

  4. Mechanical properties and collagen cross-linking of the patellar tendon in old and young men

    DEFF Research Database (Denmark)

    Couppé, C; Hansen, P; Kongsgaard, M

    2009-01-01

    were higher in OM than in YM (73 +/- 13 vs. 11 +/- 2 mmol/mol; P appreciably influence the dimensions or mechanical properties of the human patellar tendon in vivo. Collagen concentration was reduced, whereas both enzymatic......Age-related loss in muscle mass and strength impairs daily life function in the elderly. However, it remains unknown whether tendon properties also deteriorate with age. Cross-linking of collagen molecules provides structural integrity to the tendon fibrils and has been shown to change with age...... in animals but has never been examined in humans in vivo. In this study, we examined the mechanical properties and pyridinoline and pentosidine cross-link and collagen concentrations of the patellar tendon in vivo in old (OM) and young men (YM). Seven OM (67 +/- 3 years, 86 +/- 10 kg) and 10 YM (27 +/- 2...

  5. Keblish's lateral surgical approach enhances patellar tilt in valgus knee arthroplasty

    Directory of Open Access Journals (Sweden)

    José Roberto Tonelli Filho

    Full Text Available ABSTRACT OBJECTIVE: To compare the clinical and radiological outcomes of conventional medial and lateral approaches for total knee replacement in the valgus osteoarthritic knee. METHODS: In this randomized controlled trial, 21 patients with valgus knee osteoarthritis were randomized to total knee replacement through medial or lateral approach. The primary outcome was radiographic patellar tilt. Secondary outcomes were visual analog scale of pain, postoperative levels of hemoglobin, and clinical aspect of the operative wound. RESULTS: There were no differences between the groups regarding other clinical variables. Mean lateral tilt of the patella was 3.1 degrees (SD ± 5.3 in the lateral approach group and 18 degrees (SD ± 10.2 in the medial approach group (p = 0.02. There were no differences regarding the secondary outcomes. CONCLUSION: Lateral approach provided better patellar tilt following total knee replacement in valgus osteoarthritic knee.

  6. Fibril morphology and tendon mechanical properties in patellar tendinopathy: effects of heavy slow resistance training

    DEFF Research Database (Denmark)

    Kongsgaard, Mads; Qvortrup, Klaus; Larsen, Jytte Overgaard

    2010-01-01

    BACKGROUND: Patellar tendinopathy is characterized by pathologic abnormalities. Heavy slow resistance training (HSR) is effective in the management of patellar tendinopathy, but the underlying functional mechanisms remain elusive. PURPOSE: To investigate fibril morphology and mechanical properties...... assessed symptoms/function and maximal tendon pain during activity. Tendon biopsy samples were analyzed for fibril density, volume fraction, and mean fibril area. Tendon mechanical properties were assessed using force and ultrasonography samplings. RESULTS: Patients improved in symptoms/function (P = .02...... area decreased (-26% +/- 21%, P = .04) in tendinopathic tendons after HSR. CONCLUSION: Fibril morphology is abnormal in tendinopathy, but tendon mechanical properties are not. Clinical improvements after HSR were associated with changes in fibril morphology toward normal fibril density and mean fibril...

  7. Mechanical Properties of Human Patellar Tendon at the Hierarchical levels of Tendon and Fibril

    DEFF Research Database (Denmark)

    Svensson, Rene Brüggebusch; Hansen, Philip; Hassenkam, Tue

    2012-01-01

    Tendons are strong hierarchical structures, but how tensile forces are transmitted between different levels remains incompletely understood. Collagen fibrils are thought to be primary determinants of whole tendon properties, and therefore we hypothesized that the whole human patellar tendon and its...... distinct collagen fibrils would display similar mechanical properties. Human patellar tendons (n=5) were mechanically tested in vivo by ultrasonography. Biopsies were obtained from each tendon and individual collagen fibrils were dissected and tested mechanically by atomic force microscopy. The Young...... that of tendon supports that fibrillar rather than interfibrillar properties govern sub-failure tendon response, making the fibrillar level a meaningful target of intervention. The lower modulus found in vitro suggests a possible adverse effect of removing the tissue from its natural environment. In addition...

  8. Acute Traumatic Patellar Tendon Rupture at the Tibial Tuberosity Attachment without Avulsion Fracture

    Directory of Open Access Journals (Sweden)

    Shuichi Miyamoto

    2017-01-01

    Full Text Available Patellar tendon rupture in children is especially rare. The fact that the area of traumatic rupture has wide variations makes surgical treatment difficult. We present an 11-year-old boy with acute traumatic patellar tendon rupture at the tibial tuberosity attachment without avulsion fracture. Primary end-to-end repair and reinforcement using 1.5 mm stainless steel wires as a surgical strategy were undertaken. Early range of motion began with a functional knee brace and the reinforced stainless wire was removed 3 months after surgery. Knee function at the final follow-up was satisfactory. We suggest that this strategy may provide a useful option for surgical treatment.

  9. Dislocation Microstructures in Fatiqued Copper Polycrystals

    DEFF Research Database (Denmark)

    Winter, A.T.; Pedersen, Ole Bøcker; Rasmussen, K.V.

    1981-01-01

    Dislocation structures characteristic of persistent slip bands were observed in the interior of polycrystalline copper after fatigue. At low strain amplitudes, within the plateau on the cyclic stress-strain curve, only structures identical to those seen in single crystals were observed. This allows...

  10. Completion of a Dislocated Metric Space

    Directory of Open Access Journals (Sweden)

    P. Sumati Kumari

    2015-01-01

    Full Text Available We provide a construction for the completion of a dislocated metric space (abbreviated d-metric space; we also prove that the completion of the metric associated with a d-metric coincides with the metric associated with the completion of the d-metric.

  11. Frozen shoulder or missed posterior dislocation?

    African Journals Online (AJOL)

    initial diagnosis and management. ... D Leijnen,1,2 MD, MMed (Sports Med); J T Viljoen,1 BSc (Physio), MPhil (Exercise Sci); J H Kirby,1 MB ChB, MSc (Sports Med); ... diagnosis of posterior shoulder dislocation at the time of injury could.

  12. Dislocation defect interaction in irradiated Cu

    International Nuclear Information System (INIS)

    Schaeublin, R.; Yao, Z.; Spaetig, P.; Victoria, M.

    2005-01-01

    Pure Cu single crystals irradiated at room temperature to low doses with 590 MeV protons have been deformed in situ in a transmission electron microscope in order to identify the basic mechanisms at the origin of hardening. Cu irradiated to 10 -4 dpa shows at room temperature a yield shear stress of 13.7 MPa to be compared to the 8.8 MPa of the unirradiated Cu. Irradiation induced damage consists at 90% of 2 nm stacking fault tetrahedra, the remaining being dislocation loops and unidentified defects. In-situ deformation reveals that dislocation-defect interaction can take several forms. Usually, dislocations pinned by defects bow out under the applied stress and escape without leaving any visible defect. From the escape angles obtained at 183 K, an average critical stress of 100 MPa is deduced. In some cases, the pinning of dislocations leads to debris that are about 20 nm long, which formation could be recorded during the in situ experiment

  13. Missed isolated volar dislocation of the scaphoid

    DEFF Research Database (Denmark)

    Kolby, Lise; Larsen, Søren; Jørring, Stig

    2007-01-01

    A patient presented with volar dislocation of the scaphoid, the diagnosis of which had been missed for two weeks. He was treated with open reduction through a combined volar and dorsal approach with decompression of the median nerve, internal fixation, and a cast for eight weeks. One year postope...... postoperatively the functional result was good. A radiograph showed no sign of avascular necrosis....

  14. Tailoring surgical management of dislocated clavicle fractures

    NARCIS (Netherlands)

    Wijdicks, F.J.G.

    2013-01-01

    In this thesis literature research and clinical studies are presented to assist physicians in the decision making process for surgical treatment of dislocated midshaft clavicle fractures (DMCF). In Chapter 1 an introduction is given regarding the background, aim and outline of this thesis. Chapter 2

  15. Screening for congenital dislocation of the hip

    International Nuclear Information System (INIS)

    Fendel, H.

    1987-01-01

    Although the prevalence of (idiopathic) congenital dislocation of the hip (CDH) within the Member States of the European Community is not exactly known, it must be considered as a major problem of public health care and protection. By assessment of available data one can assume that between 1 and 2% of all newborns have dislocation or instability of one or both hips. There is a female predominance of 4:1 and some risk factors are known. The reasons of a higher prevalence in some areas are not yet well understood. Most of instable hips will spontaneously become stable within the first days or weeks of life. However, a considerable number of infants (less than 1%) will remain with instable hips which may dislocate. Dislocation either present at birth or as a result of persistent instability leads to subsequent hip deformation. This is a serious event for each affected individual, and is a heavy load on health care and social costs for the public. Treatment of CDH is easy and usually effective when started early, i.e. before the fourth month of life. The earlier treatment is started the easier, shorter, safer and less expensive it is and its impairment on child development and mother-child interaction can be held to a minimum. Screening for CDH is therefore the most important part of health protection in early infancy. However, this paper concludes that neither sonography nor X-ray examinations are appropriate for CDH screening

  16. Dislocation dynamics in Al-Li alloys: mean jump distance and activation length of moving dislocations

    International Nuclear Information System (INIS)

    De Hosson, J.Th.M.; Huis Int Veld, A.

    1984-01-01

    It is pointed out that aluminum-lithium based alloys offer considerable promise for structural applications, especially in the aerospace industry. This promise is related to the potential for high strength in combination with a density which is lower than that found in conventional aluminum alloys. In addition, the modulus of elasticity is higher than corresponding values in conventional aluminum alloys. A nuclear magnetic resonance study of the mechanism of dislocation motion in Al-2.2 wt pct Li is reported. Information about the effective mean jump distance of mobile dislocations is provided by in situ nuclear spin relaxation measurements. The activation length of mobile dislocations has been obtained from strain-rate change experiments on Al-2.2 wt pct Li. The considered study shows that pulsed nuclear magnetic resonance is a complementary new technique for the study of moving dislocations in Al-Li alloys. 28 references

  17. Energetics of dislocation transformations in hcp metals

    International Nuclear Information System (INIS)

    Wu, Zhaoxuan; Yin, Binglun; Curtin, W.A.

    2016-01-01

    Dislocation core structures of hcp metals are highly complex and differ significantly among the hcp family. Some dislocations undergo unconventional transformations that have significant effects on the material plastic flow. Here, the energetics of dislocation dissociations are analyzed in a general anisotropic linear elastic theory framework for transformations in which changes in the partial Burgers vectors are small. Quantitative analyses on various transformations are made using DFT-computed stacking fault energies and partial Burgers vectors. Specifically, possible transformations of the mixed, edge, and screw 〈c+a〉 and screw 〈a〉 dislocations in 6 hcp metals (Mg, Ti, Zr, Re, Zn, Cd) are studied. Climb dissociation of mixed or edge 〈c+a〉 dislocations to the Basal plane is energetically favorable in all 6 metals and thus only limited by thermal activation. The 〈c+a〉 screw dislocation is energetically preferable on Pyramidal I for Ti, Zr, and Re, and on Pyramidal II for Zn and Cd. In Mg, the energy difference between screw 〈c+a〉 on Pyramidal I and II planes is small, suggesting relatively easy cross-slip. For the screw 〈a〉, Basal dissociation is energetically favorable in Mg, Re, Zn and Cd, while Prism dissociation is strongly favorable in Ti and Zr. Only Ti, Zr and Re show a metastable state for dissociation on the Prism plane, and the energy difference between screw 〈a〉 on the Prism and Pyramidal I planes is relatively small in all systems, suggesting relatively easy cross-slip of 〈a〉 in Ti and Zr. The elastic analysis thus provides a single framework able to capture the controlling energetics for different dissociations and slip systems in hcp metals. When the calculated energy differences are very small, the results point to the need for detailed modeling of the atomistic core structure. Moreover, the analyses rationalize broad experimental observations on dominant slip systems and dislocation behaviours, and provide

  18. Dislocation Processes and Frictional Stability of Faults

    Science.gov (United States)

    Toy, V. G.; Mitchell, T. M.; Druiventak, A.

    2011-12-01

    The rate dependence of frictional processes in faults in quartzofeldspathic crust is proposed to change at c. 300°C, because above this temperature asperity deformation can be accommodated by crystal plastic processes. As a consequence, the real fault contact area increases and the fault velocity strengthens. Conversely, faults at lower temperatures are velocity weakening and therefore prone to earthquake slip. We have investigated whether dislocation processes are important around faults in quartzites on seismic timescales, by inducing fault slip on a saw cut surface in novaculite blocks. Deformation was carried out at 450°C and 600°C in a Griggs apparatus. Slip rates of 8.3 x 10-7s-1 allowed total slip, u, of 0.5mm to be achieved in c. 10 minutes. Failure occurred at peak differential stresses of ~1.7 GPa and 1.4 GPa respectively, followed by significant weakening. Structures of the novaculite within and surrounding the fault surface were examined using EBSD, FIB-SEM and TEM to elucidate changes to their dislocation substructure. In the sample deformed at 450°C, a ~50μm thick layer of amorphous / non-crystalline silica was developed on the saw-cut surface during deformation. Rare clasts of the wall rock are preserved within this material. The surrounding sample is mostly composed of equant quartz grains of 5-10μm diameter that lack a preferred orientation, contain very few intercrystalline dislocations, and are divided by organised high angle grain boundaries. After deformation, most quartz grains within the sample retain their starting microstructure. However, within ~10μm of the sliding surface, dislocations are more common, and these are arranged into elongated, tangled zones (subgrain boundaries?). Microfractures are also observed. These microstructures are characteristic of deformation accommodated by low temperature plasticity. Our preliminary observations suggest that dislocation processes may be able to accommodate some deformation around fault

  19. Eccentric Exercise in Treatment of Patellar Tendinopathy in High Level Basketball Players. A Randomized Clinical Trial.

    OpenAIRE

    Sosa, Carlos; Lorenzo Calvo, Alberto; Jiménez, Sergio L.; Bonfanti, Noelia

    2014-01-01

    Chronic patellar tendinopathy is a common pathology in sporting population. To date, there is no agreed upon protocol as election treatment. Eccentric exercises have been used with satisfactory outcomes. The purpose of this trial is compare the effects of two eccentric exercise protocols. 0.146 SJR (2014) Q4, 199/231 Health (social science), 131/169 Physical therapy, sports therapy and rehabilitation, 119/128 Sports sciences UEM

  20. Psychometric properties of a Swedish translation of the VISA-P outcome score for patellar tendinopathy

    OpenAIRE

    Frohm, Anna; Saartok, Tönu; Edman, Gunnar; Renström, Per

    2004-01-01

    Abstract Background Self-administrated patient outcome scores are increasingly recommended for evaluation of primary outcome in clinical studies. The VISA-P score, developed at the Victorian Institute of Sport Assessment in Melbourne, Australia, is a questionnaire developed for patients with patellar tendinopathy and the patients assess severity of symptoms, function and ability to participate in sport. The aim of this study was to translate the questionnaire into Swedish and to study the rel...

  1. Reliability of McConnell's classification of patellar orientation in symptomatic and asymptomatic subjects.

    Science.gov (United States)

    Watson, C J; Propps, M; Galt, W; Redding, A; Dobbs, D

    1999-07-01

    Test-retest reliability study with blinded testers. To determine the intratester reliability of the McConnell classification system and to determine whether the intertester reliability of this system would be improved by one-on-one training of the testers, increasing the variability and numbers of subjects, blinding the testers to the absence or presence of patellofemoral pain syndrome, and adhering to the McConnell classification system as it is taught in the "McConnell Patellofemoral Treatment Plan" continuing education course. The McConnell classification system is currently used by physical therapy clinicians to quantify static patellar orientation. The measurements generated from this system purportedly guide the therapist in the application of patellofemoral tape and in assessment of the efficacy of treatment interventions on changing patellar orientation. Fifty-six subjects (age range, 21-65 years) provided a total of 101 knees for assessment. Seventy-six knees did not produce symptoms. A researcher who did not participate in the measuring process determined that 17 subjects had patellofemoral pain syndrome in 25 knees. Two testers concurrently measured static patellar orientation (anterior/posterior and medial/lateral tilt, medial/lateral glide, and patellar rotation) on subjects, using the McConnell classification system. Repeat measures were performed 3-7 days later. A kappa (kappa) statistic was used to assess the degree of agreement within each tester and between testers. The kappa coefficients for intratester reliability varied from -0.06 to 0.35. Intertester reliability ranged from -0.03 to 0.19. The McConnell classification system, in its current form, does not appear to be very reliable. Intratester reliability ranged from poor to fair, and intertester reliability was poor to slight. This system should not be used as a measurement tool or as a basis for treatment decisions.

  2. The patellar tendon in junior elite volleyball players and an Olympic elite weightlifter

    OpenAIRE

    Gisslén, Karl

    2006-01-01

    The principal aim of the present thesis was to prospectively follow (clinical status and ultrasound + Doppler findings) the patellar tendons in the young elite volleyball players at the Swedish National Centre for high school volleyball in Falköping. In an Olympic weightlifter with chronic painful jumper´s knee, the effects of treatment with sclerosing injections followed by early instituted very heavy weightlifting training, was also evaluated. First, in a prevalence study, we demonstrated t...

  3. Corrective surgery for canine patellar luxation in 75 cases (107 limbs): landmark for block recession

    OpenAIRE

    Mitsuhiro Isaka; Masahiko Befu; Nami Matsubara; Mayuko Ishikawa; Yurie Arase; Toshiyuki Tsuyama; Akiko Doi; Shinichi Namba

    2014-01-01

    Canine medial patellar luxation (MPL) is a very common orthopedic disease in small animals. Because the pathophysiology of this disease involves various pathways, the surgical techniques and results vary according to the veterinarian. Further, the landmark for block recession is not completely clear. We retrospectively evaluated 75 dogs (107 limbs) with MPL in whom our landmark for block recession was used from July 2008 to May 2013. Information regarding the breed, age, sex, body weight, bod...

  4. Effect of eccentric exercise on the healing process of injured patellar tendon in rats

    OpenAIRE

    Nakamura, Kenichi; Kitaoka, Katsuhiko; Tomita, Katsuro

    2008-01-01

    Background. Earlier studies have reported positive results from eccentric training in patients with tendon disorders. The reasons for the beneficial clinical effects of eccentric training are not known. Vascularization followed by regression of the vasculature enhances the healing response of injured tendons. Eccentric exercise induces a more beneficial healing response than concentric exercise. Methods. Sixty rats with patellar tendon injuries were divided into three groups: nonexercise cont...

  5. MRI evaluation of the patellar articular cartilage in patients with subluxation of the patella

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, Katsuyuki; Inoue, Masahiro; Harada, Koushi; Murakami, Takamichi; Kim, Shougen; Fujita, Norihiko; Sakurai, Kousuke; Kozuka, Takahiro (Osaka Univ. (Japan). Faculty of Medicine)

    1991-04-01

    In patients with subluxation of the patella, injury of the patellar articular cartilage is frequently observed and correct evaluation is important to manage these patients. We examined 11 patients with subluxation of the patella and five normal volunteers. In 12 patellofemoral joints of seven patients with subluxation of the patella, the abnormalities observed on MRI were compared with those on arthroscopy and/or at operation. MRI was performed with a Magnetom 1.5 T (Siemens) using the round surface coil. Pulse sequences were SE (TR 400 ms/TE 19 ms), FLASH(TR 320 ms/TE 15 ms FA 90deg and 40deg), and SE (TR 2000 ms/TE 26, 70 ms). We analysed MR findings of the 12 abnormal joints and 10 normal joints according to the following classification of abnormalities observed on arthroscopy; normal appearance (n=3 joints), softening and fibrillation (n=6), fragmentation (n=3), and erosion to bone (n=0). In only one of the six cases with softening and fibrillation observed on arthroscopy, MRI could visualize the thickening of patellar articular cartilage, but in all three cases with fragmentation observed on arthroscopy, MRI could visualize the thin inhomogeneous cartilage with irregular surface. The combination of SE (TR 400 ms/TE 19 ms) and FLASH (TR 320 ms/TE 15 ms FA 90deg) are extremely effective pulse sequence to detect the abnormalities of patellar articular cartilage. We conclude that MRI is a useful noninvasive method of detecting advanced changes in patellar articular cartilage. (author).

  6. MRI evaluation of the patellar articular cartilage in patients with subluxation of the patella

    International Nuclear Information System (INIS)

    Nakanishi, Katsuyuki; Inoue, Masahiro; Harada, Koushi; Murakami, Takamichi; Kim, Shougen; Fujita, Norihiko; Sakurai, Kousuke; Kozuka, Takahiro

    1991-01-01

    In patients with subluxation of the patella, injury of the patellar articular cartilage is frequently observed and correct evaluation is important to manage these patients. We examined 11 patients with subluxation of the patella and five normal volunteers. In 12 patellofemoral joints of seven patients with subluxation of the patella, the abnormalities observed on MRI were compared with those on arthroscopy and/or at operation. MRI was performed with a Magnetom 1.5 T (Siemens) using the round surface coil. Pulse sequences were SE (TR 400 ms/TE 19 ms), FLASH(TR 320 ms/TE 15 ms FA 90deg and 40deg), and SE (TR 2000 ms/TE 26, 70 ms). We analysed MR findings of the 12 abnormal joints and 10 normal joints according to the following classification of abnormalities observed on arthroscopy; normal appearance (n=3 joints), softening and fibrillation (n=6), fragmentation (n=3), and erosion to bone (n=0). In only one of the six cases with softening and fibrillation observed on arthroscopy, MRI could visualize the thickening of patellar articular cartilage, but in all three cases with fragmentation observed on arthroscopy, MRI could visualize the thin inhomogeneous cartilage with irregular surface. The combination of SE (TR 400 ms/TE 19 ms) and FLASH (TR 320 ms/TE 15 ms FA 90deg) are extremely effective pulse sequence to detect the abnormalities of patellar articular cartilage. We conclude that MRI is a useful noninvasive method of detecting advanced changes in patellar articular cartilage. (author)

  7. Hydrogen diffusion in the elastic fields of dislocations in iron

    Energy Technology Data Exchange (ETDEWEB)

    Sivak, A. B., E-mail: Sivak-AB@nrcki.ru; Sivak, P. A. [National Research Centre Kurchatov Institute (Russian Federation); Romanov, V. A.; Chernov, V. M. [National Research Tomsk State University (Russian Federation)

    2016-12-15

    The effect of dislocation stress fields on the sink efficiency thereof is studied for hydrogen interstitial atoms at temperatures of 293 and 600 K and at a dislocation density of 3 × 10{sup 14} m{sup –2} in bcc iron crystal. Rectilinear full screw and edge dislocations in basic slip systems 〈111〉(110), 〈111〉(112), 〈100〉(100), and 〈100〉(110) are considered. Diffusion of defects is simulated by means of the object kinetic Monte Carlo method. The energy of interaction between defects and dislocations is calculated using the anisotropic theory of elasticity. The elastic fields of dislocations result in a less than 25% change of the sink efficiency as compared to the noninteracting linear sink efficiency at a room temperature. The elastic fields of edge dislocations increase the dislocation sink efficiency, whereas the elastic fields of screw dislocations either decrease this parameter (in the case of dislocations with the Burgers vector being 1/2〈111〉) or do not affect it (in the case of dislocations with the Burgers vector being 〈100〉). At temperatures above 600 K, the dislocations affect the behavior of hydrogen in bcc iron mainly owing to a high binding energy between the hydrogen atom and dislocation cores.

  8. Nanoscale dislocation shear loops at static equilibrium and finite temperature

    Science.gov (United States)

    Dang, Khanh; Capolungo, Laurent; Spearot, Douglas E.

    2017-12-01

    Atomistic simulations are used to determine the resolved shear stress necessary for equilibrium and the resulting geometry of nanoscale dislocation shear loops in Al. Dislocation loops with different sizes and shapes are created via superposition of elemental triangular dislocation displacement fields in the presence of an externally imposed shear stress. First, a bisection algorithm is developed to determine systematically the resolved shear stress necessary for equilibrium at 0 K. This approach allows for the identification of dislocation core structure and a correlation between dislocation loop size, shape and the computed shear stress for equilibrium. It is found, in agreement with predictions made by Scattergood and Bacon, that the equilibrium shape of a dislocation loop becomes more circular with increasing loop size. Second, the bisection algorithm is extended to study the influence of temperature on the resolved shear stress necessary for stability. An approach is presented to compute the effective lattice friction stress, including temperature dependence, for dislocation loops in Al. The temperature dependence of the effective lattice friction stress can be reliably computed for dislocation loops larger than 16.2 nm. However, for dislocation loops smaller than this threshold, the effective lattice friction stress shows a dislocation loop size dependence caused by significant overlap of the stress fields on the interior of the dislocation loops. Combined, static and finite temperature atomistic simulations provide essential data to parameterize discrete dislocation dynamics simulations.

  9. Electron-dislocation interaction at low temperatures. Progress report

    International Nuclear Information System (INIS)

    1978-01-01

    The interaction of mobile dislocations with electrons in copper and copper alloys has shown that dislocation motion in copper, at low temperature, can be treated as an analog of an underdamped oscillator. We have also shown that the viscous drag on mobile dislocations in type II superconductors can be treated as an acoustic attenuation of an elastic wave

  10. Effect of dislocations on superconductivity. O vliyanii dislokatsiy na sverkhrpovodimost'

    Energy Technology Data Exchange (ETDEWEB)

    Agap' ev, B D; Bytsenko, A A; Sukhanov, S A

    1976-01-01

    Electron-dislocation interaction is analyzed here. The effect of dislocations on the superconductor characteristics is determined according to the Ginzburg-Landau method. Appreciable changes in the stability of the superconductive state are found to occur in the vicinity of dislocations.

  11. An irreducible ankle fracture dislocation: the Bosworth injury

    NARCIS (Netherlands)

    Schepers, Tim; Hagenaars, Tjebbe; den Hartog, Dennis

    2012-01-01

    Irreducible fracture dislocations of the ankle are rare and represent true orthopedic emergencies. We present a case of a fracture dislocation that was irreducible owing to a fixed dislocation of the proximal fibular fragment posterior to the lateral ridge of the tibia. This particular type of

  12. Temporomandibular joint dislocation in an epileptic and mentally ...

    African Journals Online (AJOL)

    Theories regarding the pathogenesis of TMJ dislocation propose laxity of TMJ ligaments or capsule, excessive activity of the lateral pterygoid muscle (LPM)and erosion of the eminence'. TMJ dislocation can occur in an anterior, posterior, lateral and superior direction'. Clinical presentation of dislocated TMJ includes inability ...

  13. Lack of experience is a significant factor in the missed diagnosis of perilunate fracture dislocation or isolated dislocation

    Directory of Open Access Journals (Sweden)

    Ilker Çolak

    2018-01-01

    Conclusion: The results of this study indicated that lack of experience was the most important factor in the misdiagnosis of perilunate fracture dislocation or isolated dislocation. Level of Evidence: Level IV, diagnostic study.

  14. Structural valve deterioration in the Mitroflow biological heart valve prosthesis

    DEFF Research Database (Denmark)

    Issa, Issa Farah; Poulsen, Steen Hvitfeldt; Waziri, Farhad

    2018-01-01

    OBJECTIVES: Concern has been raised regarding the long-term durability of the Mitroflow biological heart valve prosthesis. Our aim was to assess the incidence of structural valve degeneration (SVD) for the Mitroflow bioprosthesis in a nationwide study in Denmark including all patients alive......: A total of 173 patients were diagnosed with SVD by echocardiography. Of these, 64 (11%) patients had severe SVD and 109 (19%) patients moderate SVD. Severe SVD was associated with the age of the prosthesis and small prosthesis size [Size 21: hazard ratio (95% confidence interval, CI) 2.72 (0.97-8.56), P...

  15. A modified technique for retention of orbital prosthesis

    Directory of Open Access Journals (Sweden)

    Sameera R Shaikh

    2011-01-01

    Full Text Available An orbital defect (congenital or acquired causes severe facial asymmetry and disfigurement, which results in psychological and social disturbances to the patient. It becomes a challenging task for a maxillofacial prosthodontist to fabricate a prosthesis that replicates the healthy side of the face. Success of the prosthesis depends primarily on satisfactory retention of the same. This clinical report illustrates rehabilitation of a patient with an orbital defect by fabricating a hollow orbital prosthesis, utilizing anatomical undercuts for retention using an acrylic resin template relined by a resilient denture liner.

  16. Dosimetric influence of hip prosthesis during radiotherapeutic treatment

    International Nuclear Information System (INIS)

    Gschwind, R.; Buffard, E.; Masset, H.; Makovicka, L.; David, C.; David, C.; Buffard, E.

    2008-01-01

    As the population become aged, many patients with hip prosthesis are treated for a pelvic cancer. The recommended ballistic must avoid to pass in the prosthesis, but sometimes it is inevitable. So it is essential to quantify with accuracy the dose modifications linked to the presence of metallic implant. The aim of this study is to analyze by Monte Carlo method these modifications in simple and complex models (anthropomorphic phantom) which take into account the geometry and the composition of the prosthesis and its coatings. Then, this methodology was used to study the behaviour of a treatment planning system in theses extreme conditions. (authors)

  17. Interaction of 〈1 0 0〉 dislocation loops with dislocations studied by dislocation dynamics in α-iron

    Energy Technology Data Exchange (ETDEWEB)

    Shi, X.J.; Dupuy, L. [CEA, DEN, SRMA, F-91191 Gif-sur-Yvette (France); Devincre, B. [Laboratoire d’Etude des Microstructures, CNRS-ONERA, 29 av. de la Division Leclerc, 92322 Châtillon Cedex (France); Terentyev, D. [SCK–CEN, Nuclear Materials Science Institute, Boeretang 200, B-2400 Mol (Belgium); Vincent, L. [CEA, DEN, SRMA, F-91191 Gif-sur-Yvette (France)

    2015-05-15

    Highlights: • Interactions between edge dislocations and radiation-induced loops were studied by dislocation dynamics. • Dislocation dynamics results are directly compared to molecular dynamics results. • The complex elementary reactions are successfully reproduced. • The critical shear stress to overcome individual loops if reproduced quantitatively. - Abstract: Interstitial dislocation loops with Burgers vector of 〈1 0 0〉 type are formed in α-iron under neutron or heavy ion irradiation. As the density and size of these loops increase with radiation dose and temperature, these defects are thought to play a key role in hardening and subsequent embrittlement of iron-based steels. The aim of the present work is to study the pinning strength of the loops on mobile dislocations. Prior to run massive Dislocation Dynamics (DD) simulations involving experimentally representative array of radiation defects and dislocations, the DD code and its parameterization are validated by comparing the individual loop–dislocation reactions with those obtained from direct atomistic Molecular Dynamics (MD) simulations. Several loop–dislocation reaction mechanisms are successfully reproduced as well as the values of the unpinning stress to detach mobile dislocations from the defects.

  18. Ultrasound-guided sclerosis of neovessels in painful chronic patellar tendinopathy: a randomized controlled trial.

    Science.gov (United States)

    Hoksrud, Aasne; Ohberg, Lars; Alfredson, Håkan; Bahr, Roald

    2006-11-01

    Color Doppler ultrasound examination frequently reveals neovascularization in chronic painful Achilles and patellar tendinopathy. Sclerosing the area with vascular ingrowth using polidocanol has shown promising clinical results in patients with Achilles tendinopathy. To investigate sclerosing treatment using polidocanol on a group of elite athletes with patellar tendinopathy. Randomized controlled trial/cross-over study; Level of evidence, 1. The authors recruited 33 patients (42 tendons), mainly from the Norwegian elite divisions in basketball, team handball, and volleyball. Seventeen patients (23 knees) were randomized to the treatment group (polidocanol injections in the area of neovascularization) and 16 patients (20 knees) to the control group (similar injections with lidocaine/epinephrine). After 4 months of treatment, the control group was crossed over to active treatment. Pain and function were recorded using the Victorian Institute of Sport Assessment score before the start of treatment and 4, 8, and 12 months after the first injection. Victorian Institute of Sport Assessment scores between groups were compared using multivariate analysis of variance for repeated measures. The treatment group reported a significant improvement in Victorian Institute of Sport Assessment score from 51 to 62 after 4 months; there was no change for the control group (group by time interaction, P = .052). After 8 months, when the control group had also received active treatment with polidocanol, they had a greater improvement in Victorian Institute of Sport Assessment score (58-79) than did the treatment group (54-70; group by time interaction, P = .022; time effect, P patellar tendinopathy.

  19. Rehabilitation protocol for patellar tendinopathy applied among 16- to 19-year old volleyball players.

    Science.gov (United States)

    Biernat, Ryszard; Trzaskoma, Zbigniew; Trzaskoma, Lukasz; Czaprowski, Dariusz

    2014-01-01

    The aim of the study was to investigate the efficacy of rehabilitation protocol applied during competitive period for the treatment of patellar tendinopathy. A total of 28 male volleyball players were divided into two groups. Fifteen from experimental group (E) and 13 from control group (C) fulfilled the same tests 3 times: before the training program started (first measurement), after 12 weeks (second measurement) and after 24 weeks (third measurement). The above-mentioned protocol included the following: USG imagining with color Doppler function, clinical testing, pain intensity evaluation with VISA-P questionnaire, leg muscle strength and power and jumping ability measurements. The key element of the rehabilitation program was eccentric squat on decline board with additional unstable surface. The essential factor of the protocol was a set of preventive functional exercises, with focus on eccentric exercises of hamstrings. Patellar tendinopathy was observed in 18% of the tested young volleyball players. Implementation of the presented rehabilitation protocol with eccentric squat on decline board applied during sports season lowered the pain level of the young volleyball players. Presented rehabilitation protocol applied without interrupting the competitive period among young volleyball players together with functional exercises could be an effective method for the treatment of patellar tendinopathy.

  20. PATELLAR REALIGNMENT AND FUNCTIONAL PERFORMANCE IN PATIENTS WITH PATELLOFEMORAL PAIN SYNDROME

    Directory of Open Access Journals (Sweden)

    Abeer Farag Hanafy

    2016-02-01

    Full Text Available Background: Patellar taping is used for pain relief in patients with patello-femoral pain syndrome (PFPS. Yet, there is lack of knowledge regarding its effect on the functional performance. The purpose of the study was to examine the effects of therapeutic patellar taping on the Visual Analogue Scale (VAS pain scores, number of bilateral squats, and stair climbing time in patients with PFPS. Methods: 30 female patients with PFPS with mean age 20.3± 1.46 years, weight 66.1± 9.68 kg, height 165.83 ± 3.89 cm and BMI 23.91 ± 3.50kg/m2 participated in the study. The subjects were tested randomly under three taping conditions;namely therapeutic, placebo and no-tape. The tested limb was determined to be the affected limb in patients with unilateral affection, and the symptomatic limb in patients with bilateral affection. Data was collected using the Visual Analogue Scale (VAS, Bilateral Squat Test and Timed Stair Ambulation Test. Results: Repeated measures Multivariate Analysis of Variance (MANOVA revealed that the number of bilateral squats increased significantly (p0.05 in between for the number of bilateral squats and stair climbing time. Conclusion: The findings indicated that therapeutic patellar taping is effective in improving functional performance and reducing pain in patients with patellofemoral pain syndrome (PFPS.

  1. Immediate effects of whole body vibration on patellar tendon properties and knee extension torque.

    Science.gov (United States)

    Rieder, F; Wiesinger, H-P; Kösters, A; Müller, E; Seynnes, O R

    2016-03-01

    Reports about the immediate effects of whole body vibration (WBV) exposure upon torque production capacity are inconsistent. However, the changes in the torque-angle relationship observed by some authors after WBV may hinder the measurement of torque changes at a given angle. Acute changes in tendon mechanical properties do occur after certain types of exercise but this hypothesis has never been tested after a bout of WBV. The purpose of the present study was to investigate whether tendon compliance is altered immediately after WBV, effectively shifting the optimal angle of peak torque towards longer muscle length. Twenty-eight subjects were randomly assigned to either a WBV (n = 14) or a squatting control group (n = 14). Patellar tendon CSA, stiffness and Young's modulus and knee extension torque-angle relationship were measured using ultrasonography and dynamometry 1 day before and directly after the intervention. Tendon CSA was additionally measured 24 h after the intervention to check for possible delayed onset of swelling. The vibration intervention had no effects on patellar tendon CSA, stiffness and Young's modulus or the torque-angle relationship. Peak torque was produced at ~70° knee angle in both groups at pre- and post-test. Additionally, the knee extension torque globally remained unaffected with the exception of a small (-6%) reduction in isometric torque at a joint angle of 60°. The present results indicate that a single bout of vibration exposure does not substantially alter patellar tendon properties or the torque-angle relationship of knee extensors.

  2. Description of patellar movement by 3D parameters obtained from dynamic CT acquisition

    Science.gov (United States)

    de Sá Rebelo, Marina; Moreno, Ramon Alfredo; Gobbi, Riccardo Gomes; Camanho, Gilberto Luis; de Ávila, Luiz Francisco Rodrigues; Demange, Marco Kawamura; Pecora, Jose Ricardo; Gutierrez, Marco Antonio

    2014-03-01

    The patellofemoral joint is critical in the biomechanics of the knee. The patellofemoral instability is one condition that generates pain, functional impairment and often requires surgery as part of orthopedic treatment. The analysis of the patellofemoral dynamics has been performed by several medical image modalities. The clinical parameters assessed are mainly based on 2D measurements, such as the patellar tilt angle and the lateral shift among others. Besides, the acquisition protocols are mostly performed with the leg laid static at fixed angles. The use of helical multi slice CT scanner can allow the capture and display of the joint's movement performed actively by the patient. However, the orthopedic applications of this scanner have not yet been standardized or widespread. In this work we present a method to evaluate the biomechanics of the patellofemoral joint during active contraction using multi slice CT images. This approach can greatly improve the analysis of patellar instability by displaying the physiology during muscle contraction. The movement was evaluated by computing its 3D displacements and rotations from different knee angles. The first processing step registered the images in both angles based on the femuŕs position. The transformation matrix of the patella from the images was then calculated, which provided the rotations and translations performed by the patella from its position in the first image to its position in the second image. Analysis of these parameters for all frames provided real 3D information about the patellar displacement.

  3. [Simultaneous Traumatic Rupture of Patellar Ligament and Contralateral Rupture of Quadriceps Femoris Muscle].

    Science.gov (United States)

    Hladký, V; Havlas, V

    2017-01-01

    Our paper presents a unique case of a 64-year-old patient after a fall, treated with oral antidiabetic drugs for type II diabetes mellitus. Following a series of examinations, a bilateral injury was diagnosed - patellar ligament tear on the right side and rupture of quadriceps femoris muscle on the left side. It is a rare injury, complicated by simultaneous involvement of both knee joints. The used therapy consisted of a bilateral surgery followed by gradual verticalisation, first with the support of a walking frame and later with the use of forearm crutches. During the final examination, the patient demonstrated full flexion at both knees, while an extension deficit of approx. 5 degrees was still present on the left side. The right knee X-ray showed a proper position of the patella after the removal of temporary tension band wire. Although the clinical results of operative treatment of both the patellar ligament rupture and rupture of quadriceps femoris muscle are in most cases good, early operative treatment, proper technique and post-operative rehabilitation are a prerequisite for success. Key words: knee injuries, patellar ligament, quadriceps muscle, rupture.

  4. Endoscopic bursectomy for the treatment of septic pre-patellar bursitis: a case series.

    Science.gov (United States)

    Dillon, John P; Freedman, Ilan; Tan, James S M; Mitchell, David; English, Shaun

    2012-07-01

    Operative treatment for septic pre-patellar bursitis generally involves open debridement in addition to an extended course of intravenous antibiotics. Skin necrosis and wound breakdown are potential complications of this procedure in addition to scar sensitivity and a prolonged recovery. We report endoscopic bursectomy for the treatment of septic pre-patellar bursitis in eight patients over a 3-year period. All patients had microbiological confirmation of an infective process. The average age was 36 years (23-68 years). The average hospital stay was 6 days (4-9 days). No patient had a recurrence or complained of tenderness or hypoaesthesia around their wound. No patient experienced wound complications or skin necrosis. The average return to work time was 18 days (7-22 days). We conclude that endoscopic bursectomy is a safe and effective treatment for septic pre-patellar bursitis with a shortened hospital stay and a quicker return to work than conventional open debridement.

  5. Comparison of surface coil and knee coil for evaluation of the patellar cartilage by MR imaging

    International Nuclear Information System (INIS)

    Steen, M. van den; Maeseneer, M. de; Hoste, M.; Vanderdood, K.; Ridder, F. de; Osteaux, M.

    2003-01-01

    Purpose: The aim of this work was to compare the knee coil and the surface coil for the visualisation of the patellar cartilage. Materials and methods: In 28 patients (17 women, 11 men) with an average age of 40 years (range 14-76) with knee pain MR was performed. Transverse images were obtained using a fast spin echo proton density weighted sequence on a Philips Gyroscan Intera 1.5 T clinical system. Transverse images were obtained at the level of the patellar cartilage using both the surface and the knee coil. All images were evaluated by consensus of two radiologists. They evaluated a number of quality criteria on a 4-point scale. Criteria for artefacts were also graded on a 4-point scale. Results: For the visualisation of fluid there was no significant difference between the knee coil and the surface coil (P=0.021). For all other criteria regarding image quality and presence of imaging artefacts there was a significant difference between both coils (P<0.001) with the surface coil obtaining the better result. Conclusion: The use of the surface coil in the visualisation of the patellar cartilage can be recommended at knee MR

  6. Magnetic resonance imaging-based morphological and alignment assessment of the patellofemoral joint and its relationship to proximal patellar tendinopathy

    Energy Technology Data Exchange (ETDEWEB)

    Crema, Michel D. [Hospital do Coracao (HCor) and Teleimagem, Department of Radiology, Sao Paulo, SP (Brazil); University Paris VI, Department of Radiology, Hopital Saint-Antoine, Paris (France); Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States); Cortinas, Larissa G.; Lima, Giovanni B.P.; Skaf, Abdalla Y. [Hospital do Coracao (HCor) and Teleimagem, Department of Radiology, Sao Paulo, SP (Brazil); Abdalla, Rene Jorge; McNeill Ingham, Sheila Jean [Federal University of Sao Paulo, Department of Orthopaedic Surgery, School of Medicine, Sao Paulo (Brazil); Hospital do Coracao (HCor), Knee Institute, Sao Paulo, SP (Brazil)

    2018-03-15

    To assess the differences in morphology and alignment of the knee between patients with proximal patellar tendinopathy (PPT) and a control group, using MRI and focusing on the patellofemoral joint. We retrospectively included 35 patients with clinically diagnosed and unequivocal findings of PPT on knee MRI, the case group. For the control group, we included 70 patients who underwent knee MRI for other reasons, with no clinical or MRI evidence of PPT. Patients and controls were matched for age and gender, with all subjects reporting frequent physical activity. MRIs were evaluated by two musculoskeletal radiologists, who assessed parameters of patellar morphology, trochlear morphology, patellofemoral alignment, and tibiofemoral alignment. The differences in parameters between cases and controls were assessed using Student's t test. Logistic regression was applied to assess the associations between the MRI parameters and the presence of PPT. The patellar height Insall-Salvati ratio was different between cases and controls (1.37 ± 0.21 vs. 1.24 ± 0.19; p = 0.003). The subchondral Wiberg angle was higher in cases than controls (136.8 ± 7.4 vs. 131.7 ± 8.8; p = 0.004). After applying logistic regression, significant associations with PPT were found [odds ratios (95% CI)] for patellar morphology [1.1 (1.0, 1.2)] and patellar height [1.3 (1.0, 1.7)]. Patellar height and the subchondral patellar Wiberg angle were greater in patients with PPT and significantly associated with PPT. (orig.)

  7. Magnetic resonance imaging-based morphological and alignment assessment of the patellofemoral joint and its relationship to proximal patellar tendinopathy

    International Nuclear Information System (INIS)

    Crema, Michel D.; Cortinas, Larissa G.; Lima, Giovanni B.P.; Skaf, Abdalla Y.; Abdalla, Rene Jorge; McNeill Ingham, Sheila Jean

    2018-01-01

    To assess the differences in morphology and alignment of the knee between patients with proximal patellar tendinopathy (PPT) and a control group, using MRI and focusing on the patellofemoral joint. We retrospectively included 35 patients with clinically diagnosed and unequivocal findings of PPT on knee MRI, the case group. For the control group, we included 70 patients who underwent knee MRI for other reasons, with no clinical or MRI evidence of PPT. Patients and controls were matched for age and gender, with all subjects reporting frequent physical activity. MRIs were evaluated by two musculoskeletal radiologists, who assessed parameters of patellar morphology, trochlear morphology, patellofemoral alignment, and tibiofemoral alignment. The differences in parameters between cases and controls were assessed using Student's t test. Logistic regression was applied to assess the associations between the MRI parameters and the presence of PPT. The patellar height Insall-Salvati ratio was different between cases and controls (1.37 ± 0.21 vs. 1.24 ± 0.19; p = 0.003). The subchondral Wiberg angle was higher in cases than controls (136.8 ± 7.4 vs. 131.7 ± 8.8; p = 0.004). After applying logistic regression, significant associations with PPT were found [odds ratios (95% CI)] for patellar morphology [1.1 (1.0, 1.2)] and patellar height [1.3 (1.0, 1.7)]. Patellar height and the subchondral patellar Wiberg angle were greater in patients with PPT and significantly associated with PPT. (orig.)

  8. Effects of In-Season Inertial Resistance Training With Eccentric Overload in a Sports Population at Risk for Patellar Tendinopathy.

    Science.gov (United States)

    Gual, Gabriel; Fort-Vanmeerhaeghe, Azahara; Romero-Rodríguez, Daniel; Tesch, Per A

    2016-07-01

    Gual, G, Fort-Vanmeerhaeghe, A, Romero-Rodríguez, D, and Tesch, PA. Effects of in-season inertial resistance training with eccentric overload in a sports population at risk for patellar tendinopathy. J Strength Cond Res 30(7): 1834-1842, 2016-Volleyball and basketball players can be considered as a population at risk for patellar tendinopathy. Given the paradox that eccentric training elicits therapeutic benefits yet might provoke such injury, we investigated the influence of a weekly bout of inertial squat resistance exercise offering eccentric overload on lower limb muscle power and patellar tendon complaints. Players of 8 (4 basketball and 4 volleyball) teams (38 women and 43 men) were randomly assigned to either the intervention (IG) or control (CG) group. Although IG and CG maintained scheduled in-season training routines over 24 weeks, IG, in addition, performed 1 weekly session of eccentric overload by 4 sets of 8 repetitions of the squat using flywheel inertial resistance. Victorian Institute of Sports Assessment patellar tendinopathy questionnaire (VISA-p), vertical countermovement jump, and squat power, both concentric (Squat-Con) and eccentric (Squat-Ecc), tests were performed before (T1), during (T2), and after (T3) the 24 weeks of intervention. Neither group suffered from patellar tendinopathy during the study period. VISA-p displayed no differences across groups at any measurement period. Countermovement jump scores significantly (p ≤ 0.05) differed between groups in favor of the IG. Both Squat-Con and Squat-Ecc mean scores from the IG were significantly (p training bout to a regular basketball and volleyball exercise routine enhances lower limb muscle power without triggering patellar tendon complaints. Future studies, using the current exercise paradigm, aim to explore its efficacy to prevent or combat patellar tendinopathy in sports calling for frequent explosive jumps.

  9. Stress-free states of continuum dislocation fields : Rotations, grain boundaries, and the Nye dislocation density tensor

    NARCIS (Netherlands)

    Limkumnerd, Surachate; Sethna, James P.

    We derive general relations between grain boundaries, rotational deformations, and stress-free states for the mesoscale continuum Nye dislocation density tensor. Dislocations generally are associated with long-range stress fields. We provide the general form for dislocation density fields whose

  10. Technical note: validation of a motion analysis system for measuring the relative motion of the intermediate component of a tripolar total hip arthroplasty prosthesis.

    Science.gov (United States)

    Chen, Qingshan; Lazennec, Jean Yves; Guyen, Olivier; Kinbrum, Amy; Berry, Daniel J; An, Kai-Nan

    2005-07-01

    Tripolar total hip arthroplasty (THA) prosthesis had been suggested as a method to reduce the occurrence of hip dislocation and microseparation. Precisely measuring the motion of the intermediate component in vitro would provide fundamental knowledge for understanding its mechanism. The present study validates the accuracy and repeatability of a three-dimensional motion analysis system to quantitatively measure the relative motion of the intermediate component of tripolar total hip arthroplasty prostheses. Static and dynamic validations of the system were made by comparing the measurement to that of a potentiometer. Differences between the mean system-calculated angle and the angle measured by the potentiometer were within +/-1 degrees . The mean within-trial variability was less than 1 degrees . The mean slope was 0.9-1.02 for different angular velocities. The dynamic noise was within 1 degrees . The system was then applied to measure the relative motion of an eccentric THA prosthesis. The study shows that this motion analysis system provides an accurate and practical method for measuring the relative motion of the tripolar THA prosthesis in vitro, a necessary first step towards the understanding of its in vivo kinematics.

  11. Work softening in nanocrystalline materials induced by dislocation annihilation

    DEFF Research Database (Denmark)

    Ungar, Tamas; Li, Li; Tichy, Geza

    2011-01-01

    Cold rolling reduces the quantity of dislocation densities in Ni–18% Fe alloys prepared by electrochemical deposition. The dislocation density evolution proposed earlier for the linearly decreasing work-hardening rate during stage III is revisited. The solution of the differential equation predicts...... that when the initial dislocation density is smaller or larger than the saturation value, then the dislocation density will increase or decrease during further plastic deformation. The predictions are verified by experimental values of dislocation densities determined by X-ray line-profile analysis....

  12. Electron-dislocation interaction at low temperatures. Progress report

    International Nuclear Information System (INIS)

    1976-01-01

    Studies of the interaction of mobile dislocations with electrons have shown that dislocation motion can be, in part, described by treating the dislocation as an underdamped oscillator. In particular, studies in lead alloys have shown tht dislocation motion can be considered as the motion of string, slightly damped by electrons, without regard for any other lattice friction. In addition we have shown that silver solutes, in lead crystals, occupy, partially, interstitial sites. Finally, we have shown that dislocations in copper interact, unexpectedly, with electrons. This is shown by measuring the influence of a magnetic field on the flow stress of copper crystals at 4.2 0 K

  13. COMPARISON OF FUNCTIONAL ACTIVITIES ON STRUCTURAL CHANGES OF THE INFERIOR PATELLAR POLE

    Science.gov (United States)

    Wallmann, Harvey; Stalcup, Patrick; DiTommaso, Katie

    2017-01-01

    Background It is well known that eccentric and concentric exercise produce varied amounts of stress on the connective tissues. Diagnostic ultrasound has been used to measure these structural changes by observing fascicle length, angle, and thickness; however, there is a lack of evidence comparing the structural changes as it relates to eccentric, concentric, and stretching protocols. Purpose The purpose of this study was to compare the acute effects of static stretching, eccentric, concentric, and a combination of eccentric/concentric exercises on structural changes of the muscle tendon unit at the inferior patellar pole utilizing the diagnostic ultrasound. Study Design A repeated measures 2 × 4 within factorial study design with repeated measures on both factors was used to determine the differences in patellar tendon thickness within and between groups. Methods Forty-seven healthy subjects were screened for any lower extremity deficits or orthopaedic pathology. Forty-four (N=44) subjects completed all four protocols; the attrition was due to injuries to the lower extremity, occurring unrelated to the study. A baseline measurement of the anterior inferior patellar tendon was performed with the diagnostic ultrasound prior to each participant completing one of the four interventions per week over a four-week period. Interventions completed by each participant included static stretching, concentric, eccentric, and combined concentric and eccentric exercises. Immediately following each intervention, a post-intervention inferior patellar tendon measurement was recorded using the diagnostic ultrasound. Results Significant differences in anterior to posterior tendon thickness of the inferior patellar tendon were observed between pre (4.983 ± 0.041mm) and post (5.198 ± 0.055mm) measurements (peffect of time. However, no differences in tendon thickness were noted comparing each intervention to one another (p=0.351). Conclusion Differences in tendon thickness

  14. Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

    National Research Council Canada - National Science Library

    Humayun, M

    2001-01-01

    An electronic retinal prosthesis is under development to treat retinitis pigmentosa and age-related macular degeneration, two presently incurable diseases of the outer retina that afflict millions world-wide...

  15. 21 CFR 878.3750 - External prosthesis adhesive.

    Science.gov (United States)

    2010-04-01

    ... used to fasten to the body an external aesthetic restoration prosthesis, such as an artificial nose. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in...

  16. Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

    National Research Council Canada - National Science Library

    Humayun, M

    2001-01-01

    .... Previous studies have established the feasibility of the retinal prosthesis. Short-term tests in blind humans have shown that degenerated retina will respond to light in a way that is consistent with form vision...

  17. Metabolics of stair ascent with a powered transfemoral prosthesis.

    Science.gov (United States)

    Ledoux, E D; Lawson, B E; Shultz, A H; Bartlett, H L; Goldfarb, M

    2015-01-01

    This paper evaluates the effectiveness of a powered knee and ankle prosthesis for stair ascent through a metabolic assessment comparing energy expenditure of a single transfemoral amputee subject while ascending stairs with the powered prosthesis relative to his passive daily use device, as well as comparing the kinematics and kinetics obtained with the passive prosthesis to healthy biomechanics. The subject wore a portable system that measured pulmonary gaseous exchange rates of oxygen and carbon dioxide while he ascended stairs with each of the prostheses in alternating tests. The results indicated that the amputee's energy expenditure decreased by 32 percent while climbing with the powered prosthesis as compared to his passive one, and the kinematics and kinetics achieved were representative of healthy biomechanics.

  18. BILATERAL PATHOLOGICAL HIP DISLOCATION IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Yuriy E. Garkavenko

    2017-03-01

    Full Text Available Introduction. Pathological dislocation of the hip is one of the most severe complications of acute hematogenous osteomyelitis. The program of treatment for children with pathological hip dislocation is complex, but it has been sufficiently developed and implemented very successfully. At the same time, the available literature provides no cases of treating children with bilateral pathological hip dislocations after hematogenous osteomyelitis. There is no information on the incidence of such cases or in regards to remote functional results. Materials and methods. The results of the treatment of 18 children with bilateral pathological dislocation of the hip after hematogenous osteomyelitis are presented, which constituted 23.1% of the total number of patients (78 who underwent surgery in 2000–2016 for the diagnosis of pathological hip dislocation. Both hip joints were surgically operated on in 12 patients, while one hip joint was operated on in 6 patients. To assess the anatomical and functional state of hip joints, the clinical and roentgenological diagnostic techniques were used. Results and discussion. To stabilize and restore the function of the hip joints, 18 children underwent 30 surgical interventions: simple open hip reduction (19 and open hip reduction with hip arthroplasty with one (6 or two (5 demineralized osteochondral allogeneic grafts. The decision regarding the possibility of performing surgical intervention on the second hip joint was made only after a child's check-up examination was complete and after positive information about the anatomical and functional state of the operated hip joint was obtained. According to these criteria, 14 (77.8% children underwent surgical treatment of the second hip joint 1–1.5 years after the course of conservative measures to restore the range of motion in the previously operated hip joint. Over a period of 1–12 years, 17 patients were examined, 10 of which underwent an operation on both

  19. Recombination properties of dislocations in GaN

    Science.gov (United States)

    Yakimov, Eugene B.; Polyakov, Alexander Y.; Lee, In-Hwan; Pearton, Stephen J.

    2018-04-01

    The recombination activity of threading dislocations in n-GaN with different dislocation densities and different doping levels was studied using electron beam induced current (EBIC). The recombination velocity on a dislocation, also known as the dislocation recombination strength, was calculated. The results suggest that dislocations in n-GaN giving contrast in EBIC are charged and surrounded by a space charge region, as evidenced by the observed dependence of dislocation recombination strength on dopant concentration. For moderate (below ˜108 cm-2) dislocation densities, these defects do not primarily determine the average diffusion length of nonequilibrium charge carriers, although locally, dislocations are efficient recombination sites. In general, it is observed that the effect of the growth method [standard metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth versions of MOCVD, and hydride vapor phase epitaxy] on the recombination activity of dislocations is not very pronounced, although the average diffusion lengths can widely differ for various samples. The glide of basal plane dislocations at room temperature promoted by low energy electron irradiation does not significantly change the recombination properties of dislocations.

  20. Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

    Science.gov (United States)

    Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

    2015-01-01

    Background: The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0–135° flexion. Results: Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, “rollback” compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis. PMID:25591565

  1. Rehabilitation of single finger amputation with customized silicone prosthesis

    OpenAIRE

    Yadav, Niharika; Chand, Pooran; Jurel, Sunit Kumar

    2016-01-01

    Finger amputations are common in accidents at home, work, and play. Apart from trauma, congenital disease and deformity also leads to finger amputation. This results in loss of function, loss of sensation as well as loss of body image. Finger prosthesis offers psychological support and social acceptance in such cases. This clinical report describes a method to fabricate ring retained silicone finger prosthesis in a patient with partial finger loss.

  2. Kinematic analysis of a posterior-stabilized knee prosthesis.

    Science.gov (United States)

    Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

    2015-01-20

    The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

  3. Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

    Directory of Open Access Journals (Sweden)

    Zhi-Xin Zhao

    2015-01-01

    Full Text Available Background: The goal of total knee arthroplasty (TKA is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Results: Both the output data trends and the measured values derived from the normal knee′s kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

  4. Thermally activated dislocation motion including inertial effects in solid solutions

    International Nuclear Information System (INIS)

    Isaac, R.D.

    1977-01-01

    Dislocation motion through an array of obstacles is considered in terms of the potential energy of the dislocation as it moves through the array. The obstacles form a series of potential wells and barriers which can trap the dislocations. The effect of thermal fluctuations and of a viscous drag on the motion of the dislocation is investigated by analogy with Brownian motion in a field of force. The rate of escape of a trapped dislocation is found to depend on the damping coefficient only for a large viscous drag. The probability that a dislocation will be trapped by a well or barrier is found to depend on the damping coefficient for a small viscous drag. This inertial effect determines how far a dislocation will travel after breaking away from an obstacle

  5. Ultrasound as a probe of dislocation density in aluminum

    International Nuclear Information System (INIS)

    Mujica, Nicolás; Cerda, Maria Teresa; Espinoza, Rodrigo; Lisoni, Judit; Lund, Fernando

    2012-01-01

    Graphical abstract: Display Omitted - Abstract: Dislocations are at the heart of the plastic behavior of crystalline materials yet it is notoriously difficult to perform quantitative, non-intrusive measurements of their single or collective properties. Dislocation density is a critical variable that determines dislocation mobility, strength and ductility. On the one hand, individual dislocations can be probed in detail with transmission electron microscopy. On the other hand, their collective properties must be simulated numerically. Here we show that ultrasound technology can be used to measure dislocation density. This development rests on theory—a generalization of the Granato–Lücke theory for the interaction of elastic waves with dislocations—and resonant ultrasound spectroscopy (RUS) measurements. The chosen material is aluminum, to which different dislocation contents were induced through annealing and cold-rolling processes. The dislocation densities obtained with RUS compare favorably with those inferred from X-ray diffraction, using the modified Williamson–Hall method.

  6. Electrical conduction along dislocations in plastically deformed GaN

    Energy Technology Data Exchange (ETDEWEB)

    Kamimura, Y; Yokoyama, T; Oiwa, H; Edagawa, K [Institute of Industrial Science, the University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505 (Japan); Yonenaga, I, E-mail: yasushi@iis.u-tokyo.ac.jp [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577 (Japan)

    2009-07-15

    Electrical conduction along dislocations in plastically deformed n-GaN single crystals has been investigated by scanning spread resistance microscopy (SSRM). In the SSRM images, many conductive spots have been observed, which correspond to electrical conduction along the dislocations introduced by deformation. Here, the introduced dislocations are b=(a/3)<1overline 210> edge dislocations parallel to the [0001] direction. The current values at the spots normalized to the background current value are larger than 100. Previous works have shown that grown-in edge dislocations in GaN are nonconductive. The high conductivity of the deformation-introduced edge dislocations in the present work suggests that the conductivity depends sensitively on the dislocation core structure.

  7. Availability of Dental Prosthesis Procedures in Brazilian Primary Health Care

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Gonçalves Melo Cunha

    2018-01-01

    Full Text Available Objectives. To describe dental prosthesis provision in the Brazilian public health service and report the performance of dental prosthesis procedures according to the Brazilian macroregions. Methods. A structured interview was conducted with senior-level health professionals from each of the 18,114 oral health teams (OHT. The dependent variables were performance of removable prostheses and prosthesis procedures, including provision of fixed prostheses by OHT. Descriptive statistics were produced together with performing a cluster analysis using SPSS version 19.0. Results. The manufacture of any type of prosthesis was done by a minority of OHT (43%. The most commonly provided types of dental prosthesis were removable full and partial dentures. Cluster 1 (teams that performed prosthesis procedures the most was composed of a smaller number of teams (n = 5,531, and Cluster 2 (composed of teams that do not perform prosthetics or that perform them in small amounts consisted of 12,583 teams. The geographic distribution of clusters reveals that the largest proportion of Cluster 1 teams is located in the Northeast (33.9% and Southeast (33.6%. Conclusions. A minority of OHT produce dental prostheses. There is an unequal geographical distribution of clusters.

  8. Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation.

    Science.gov (United States)

    Chen, Cheng; Ren, Wenhao; Gao, Ling; Cheng, Zheng; Zhang, Linmei; Li, Shaoming; Zhi, Pro Ke-qian

    2016-01-01

    Maxillary defects are usually rehabilitated by a prosthetic obturator. This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS). From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP), 11 (39%) with an enhanced retentive obturator prosthesis with stud attachment (POP) and 8 (28%) with an enhanced retentive obturator prosthesis with magnetic attachment (POM). The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p<0.05) among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p<0.05) both in MOP and AOP groups. Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  9. Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation

    Directory of Open Access Journals (Sweden)

    Cheng Chen

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Maxillary defects are usually rehabilitated by a prosthetic obturator. OBJECTIVE: This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. METHODS: Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS. RESULTS: From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP, 11 (39% with an enhanced retentive obturator prosthesis with stud attachment (POP and 8 (28% with an enhanced retentive obturator prosthesis with magnetic attachment (POM. The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p < 0.05 among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p < 0.05 both in MOP and AOP groups. CONCLUSION: Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function.

  10. Failed total carpometacarpal joint prosthesis of the thumb

    DEFF Research Database (Denmark)

    Hansen, Torben Bæk; Homilius, Morten

    2010-01-01

    Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis. T...... in eight of 10 patients, but the mean Disabilities of the arm, shoulder, and hand (DASH) scores, self-reported pinch-grip-related function, and pain were comparable with our earlier published results with the Elektra carpometacarpal total joint prosthesis.......Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis....... The male:female ratio was 1:4 and the mean duration of observation 32 months (range 6-52). In three patients the revised implant was a MOJE uncemented carpometacarpal joint prosthesis and in seven patients an Elektra uncemented one. At follow-up grip strength was reduced to less than 90% of the other hand...

  11. Clinical improvements are not explained by changes in tendon structure on UTC following an exercise program for patellar tendinopathy.

    Science.gov (United States)

    van Ark, Mathijs; Rio, Ebonie; Cook, Jill; van den Akker-Scheek, Inge; Gaida, James E; Zwerver, Johannes; Docking, Sean

    2018-04-11

    The aim of this study was to investigate the effects of a 4-week in-season exercise program of isometric or isotonic exercises on tendon structure and dimensions as quantified by Ultrasound Tissue Characterization (UTC). Randomized clinical trial. Volleyball and basketball players (16-31 years, n=29) with clinically diagnosed patellar tendinopathy were randomized to a 4-week isometric or isotonic exercise program. The programs were designed to decrease patellar tendon pain. A baseline and 4-week UTC scan was used to evaluate change in tendon structure. No significant change in tendon structure or dimensions on UTC was detected after the exercise program, despite patellar tendinopathy symptoms improving. The percentage and mean cross-sectional area (mCSA) of aligned fibrillar structure (echo-types I+II) (Z=-0.414,p=0.679) as well as disorganized structure (echo-types III + IV) (Z=-0.370,p=0.711) did not change over the 4-week exercise program. Change in tendon structure and dimensions on UTC did not differ significantly between the groups. Structural properties and dimensions of the patellar tendon on UTC did not change after a 4-week isometric or isotonic exercise program for athletes with patellar tendinopathy in-season, despite an improvement of symptoms. It seems that structural improvements are not required for a positive clinical outcome.

  12. Chirality-controlled crystallization via screw dislocations.

    Science.gov (United States)

    Sung, Baeckkyoung; de la Cotte, Alexis; Grelet, Eric

    2018-04-11

    Chirality plays an important role in science from enantiomeric separation in chemistry to chiral plasmonics in nanotechnology. However, the understanding of chirality amplification from chiral building blocks to ordered helical superstructures remains a challenge. Here, we demonstrate that topological defects, such as screw dislocations, can drive the chirality transfer from particle to supramolecular structure level during the crystallization process. By using a model system of chiral particles, which enables direct imaging of single particle incorporation into growing crystals, we show that the crystallization kinetic pathway is the key parameter for monitoring, via the defects, the chirality amplification of the crystalline structures from racemic to predominantly homohelical. We provide an explanation based on the interplay between geometrical frustration, racemization induced by thermal fluctuations, and particle chirality. Our results demonstrate that screw dislocations not only promote the growth, but also control the chiral morphology and therefore the functionality of crystalline states.

  13. Delayed cementless total hip arthroplasty for neglected dislocation of hip combined with complex acetabular fracture and deficient bone stock

    Directory of Open Access Journals (Sweden)

    Gavaskar Ashok S

    2012-12-01

    Full Text Available 【Abstract】Total hip arthroplasty (THA for an un-treated acetabular fracture is technically challenging and the long-term result is not so favorable. A 45-year-old fe-male patient with untreated column and comminuted poste-rior wall fracture of the acetabulum was treated in our insti-tution by reconstruction of the posterior wall using iliac strut autograft and plate stabilization of the posterior col-umn with cancellous grafting and cementless THA in a single stage. At 3 years’ follow-up, the patient was independently mobile without limb length discrepancy. Radiological evalu-ation showed well integrated components and bone grafts. No evidence of aseptic loosening or osteolysis was found. This report aims to emphasize that bony acetabular recon-struction allows the use of primary hip components, which improves prosthesis longevity and preserves bone stock for a future revision. Key words: Acetabulum; Fractures, bone; Hip dislocation; Arthroplasty, replacement, hip

  14. Quasicontinuum analysis of dislocation-coherent twin boundary interaction to provide local rules to discrete dislocation dynamics

    Science.gov (United States)

    Tran, H.-S.; Tummala, H.; Duchene, L.; Pardoen, T.; Fivel, M.; Habraken, A. M.

    2017-10-01

    The interaction of a pure screw dislocation with a Coherent Twin Boundary Σ3 in copper was studied using the Quasicontinuum method. Coherent Twin Boundary behaves as a strong barrier to dislocation glide and prohibits slip transmission across the boundary. Dislocation pileup modifies the stress field at its intersection with the Grain Boundary (GB). A methodology to estimate the strength of the barrier for a dislocation to slip across CTB is proposed. A screw dislocation approaching the boundary from one side either propagates into the adjacent twin grain by cutting through the twin boundary or is stopped and increases the dislocation pileup amplitude at the GB. Quantitative estimation of the critical stress for transmission was performed using the virial stress computed by Quasicontinuum method. The transmission mechanism and critical stress are in line with the literature. Such information can be used as input for dislocation dynamic simulations for a better modeling of grain boundaries.

  15. Traumatic atlantooccipital dislocation injury in children.

    Science.gov (United States)

    Nichols, J; West, J S

    1994-10-01

    The tragedy of trauma turns into triumph when the surgery team members' efforts result in victory for the patient. Nowhere is this more true than in successful pediatric trauma care. Giving a child a second chance at life and the family an opportunity for a new beginning is the highest reward for the trauma team's years of professional training and practice. Traumatic atlantoocipital dislocation injury usually results in death, but recent neurosurgery trauma advances are increasing pediatric survival rates.

  16. Dislocation dynamics simulations in a cylinder

    International Nuclear Information System (INIS)

    Weinberger, Christopher R; Aubry, Sylvie; Cai, Wei; Lee, Seok-Woo

    2009-01-01

    In this work we describe how to perform dislocation dynamics simulations in a cylindrical geometry. An algorithm for computing the image stress is given in detail including methods for handling the singularity. Additional remesh rules address the problems of the cylindrical geometry and the required self consistency with mobility laws. Numerical studies benchmark the accuracy of the algorithms and the importance of handling the singularity correctly.

  17. Irreducible lateral dislocation of the elbow.

    Directory of Open Access Journals (Sweden)

    Chhaparwal M

    1997-01-01

    Full Text Available A rare case of an irreducible post-traumatic lateral dislocation of elbow is presented. The mechanism of injury was fall on a flexed elbow with trauma on its medial aspect resulting in pronation of the forearm. At open reduction, the brachialis muscle was in the form of a tight band which prevented reduction. The ulnar nerve was entrapped in the joint.

  18. Dislocation Concepts in Friction and Wear.

    Science.gov (United States)

    1980-12-01

    geometrica considerations, and other basic facts concerning plastic Drover ties of crystalline materials, a numiber of qualitative and quanI titative... correct but, in connection with cell walls, it is generally erroneous as indicated. Fig. 27 demonstrates this clearly: The dislocation cells make the...is certainly promising. If it is then assumed that it is basically correct , one may be impressed with the underlying simplicity of the mechanisms

  19. Comparison of reliability of five patellar position indices at various stifle joint angles in pelvic limbs obtained from cadavers of red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Miles, James E; Nielsen, Dorte H; Jensen, Bente Rona

    2012-01-01

    To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use.......To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use....

  20. The TOPSHOCK study : Effectiveness of radial shockwave therapy compared to focused shockwave therapy for treating patellar tendinopath - Design of a randomised controlled trial

    NARCIS (Netherlands)

    van der Worp, H.; Zwerver, J.; van den Akker-Scheek, I.; Diercks, R.L.

    2011-01-01

    Background: Patellar tendinopathy is a chronic overuse injury of the patellar tendon that is especially prevalent in people who are involved in jumping activities. Extracorporeal Shockwave Therapy is a relatively new treatment modality for tendinopathies. It seems to be a safe and promising part of

  1. Congenital hip dislocation: Radiological screening or diagnosis?

    International Nuclear Information System (INIS)

    Kalifa, G.; Faure, C.

    1987-01-01

    Congenital hip dislocation is a perfect example of public health problems: its incidence is high 0.6, to 2% of newborns in France and an early detection allows an easy and successful treatment. The current situation in our country is not satisfactory for several reasons: - Too many children are treated without reasons because of misleading radiological pictures; - Conversely, some dislocations are discovered only at the walking age, the treatment becoming then more difficult and less effective; - Almost 300,000 radiological examinations of the hip for screening are performed each year and among them 100,000 in newborns. This is not satisfactory as it is commonly admitted now that radiological examination at birth is unreliable and frequently misleading. For all these reasons a special working group has been settled up by the General Direction of Health, including physicians of different practices, from different specialities. The conclusion of this group will be published in a special booklet and can be summarized as follows: The group recommends to perform detection of congenital hip dislocation mainly by the clinical examination. This examination may be difficult but it must be performed very early, the first day of life, repeated several times, at the end of the first week and during the first, second, and third month. Every baby in this country must undergo several clinical examinations up to one year of age

  2. Prosthetic replacement of the medial meniscus in cadaveric knees - Does the prosthesis mimic the functional behavior of the native meniscus?

    NARCIS (Netherlands)

    Tienen, TG; Verdonschot, N; Heijkants, RGJC; Buma, R; Scholten, JGF; van Kampen, A; Veth, RPH

    2004-01-01

    Meniscus replacement by a polymer meniscus prosthesis in dogs resulted in generation of new meniscal tissue. Hypothesis: Optimal functioning of the prosthesis would involve realistic deformation and motion patterns of the prosthesis during knee joint motion. Study Design: Controlled laboratory

  3. Influence of acetaminophen and ibuprofen on in vivo patellar tendon adaptations to knee extensor resistance exercise in older adults

    DEFF Research Database (Denmark)

    Carroll, C C; Dickinson, J M; LeMoine, J K

    2011-01-01

    adults induces modest changes in the mechanical properties of the patellar tendon. Over-the-counter doses of acetaminophen, but not ibuprofen, have a strong influence on tendon mechanical and material property adaptations to resistance training. These findings add to a growing body of evidence......Millions of older individuals consume acetaminophen or ibuprofen daily and these same individuals are encouraged to participate in resistance training. Several in vitro studies suggest that cyclooxygenase-inhibiting drugs can alter tendon metabolism and may influence adaptations to resistance...... tendon properties were assessed with MRI [cross-sectional area (CSA) and signal intensity] and ultrasonography of patellar tendon deformation coupled with force measurements to obtain stiffness, modulus, stress, and strain. Mean patellar tendon CSA was unchanged (P > 0.05) with training in the placebo...

  4. Neovascularity in patellar tendinopathy and the response to eccentric training: a case report using Power Doppler ultrasound.

    Science.gov (United States)

    McCreesh, Karen M; Riley, Sara J; Crotty, James M

    2013-12-01

    This report describes the case of an amateur soccer player with chronic patellar tendinopathy who underwent ultrasound imaging before and after engaging in an 8-week programme of eccentric exercise. On initial assessment, greyscale ultrasound imaging demonstrated tendon thickening and reduced echogenicity, while Power Doppler imaging demonstrated a large amount of neovascularity. After 8 weeks of an eccentric loading programme, the patient reported significantly improved symptoms and functional scores, while follow-up imaging demonstrated improvement in the echo appearance of the tendon and complete resolution of the neovascularity. The association between neovascularity and symptoms in tendinopathy research is conflicting, with a paucity of research in the area of patellar tendinopathy. While further research is needed to clarify the significance of greyscale and Power Doppler ultrasound changes in relation to symptoms in patellar tendinopathy, ultrasound imaging was shown to be a useful adjunct to diagnosis and outcome assessment in this case. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Successful conservative management of symptomatic bilateral dorsal patellar defects presenting with cartilage involvement and bone marrow edema: MRI findings

    International Nuclear Information System (INIS)

    Kwee, Thomas C.; Sonneveld, Heleen; Nix, Maarten

    2016-01-01

    The dorsal patellar defect is a relatively rare entity that involves the superolateral quadrant of the patella. It is usually considered to represent a delayed ossification process, although its exact origin remains unclear. Because of its usually innocuous nature and clinical course, invasive interventions are generally deemed unnecessary, although curretage has been successfully performed on symptomatic cases. This case report presents a rather unusual case of symptomatic bilateral dorsal patellar defects with cartilage involvement and widespread surrounding bone marrow edema as demonstrated by magnetic resonance imaging (MRI). Both cartilage involvement and bone marrow edema should be considered part of the spectrum of associated MRI findings that can be encountered in this entity. Furthermore, the presented case shows that symptomatic dorsal patellar defects can be treated conservatively with success and that (decrease of) pain symptoms are likely related to (decrease of) bone marrow edema. (orig.)

  6. Successful conservative management of symptomatic bilateral dorsal patellar defects presenting with cartilage involvement and bone marrow edema: MRI findings.

    Science.gov (United States)

    Kwee, Thomas C; Sonneveld, Heleen; Nix, Maarten

    2016-05-01

    The dorsal patellar defect is a relatively rare entity that involves the superolateral quadrant of the patella. It is usually considered to represent a delayed ossification process, although its exact origin remains unclear. Because of its usually innocuous nature and clinical course, invasive interventions are generally deemed unnecessary, although curretage has been successfully performed on symptomatic cases. This case report presents a rather unusual case of symptomatic bilateral dorsal patellar defects with cartilage involvement and widespread surrounding bone marrow edema as demonstrated by magnetic resonance imaging (MRI). Both cartilage involvement and bone marrow edema should be considered part of the spectrum of associated MRI findings that can be encountered in this entity. Furthermore, the presented case shows that symptomatic dorsal patellar defects can be treated conservatively with success and that (decrease of) pain symptoms are likely related to (decrease of) bone marrow edema.

  7. Successful conservative management of symptomatic bilateral dorsal patellar defects presenting with cartilage involvement and bone marrow edema: MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Meander Medical Center, Department of Radiology, Amersfoort (Netherlands); Sonneveld, Heleen [Meander Medical Center, Department of Orthopaedics, Amersfoort (Netherlands); Nix, Maarten [Meander Medical Center, Department of Radiology, Amersfoort (Netherlands)

    2016-05-15

    The dorsal patellar defect is a relatively rare entity that involves the superolateral quadrant of the patella. It is usually considered to represent a delayed ossification process, although its exact origin remains unclear. Because of its usually innocuous nature and clinical course, invasive interventions are generally deemed unnecessary, although curretage has been successfully performed on symptomatic cases. This case report presents a rather unusual case of symptomatic bilateral dorsal patellar defects with cartilage involvement and widespread surrounding bone marrow edema as demonstrated by magnetic resonance imaging (MRI). Both cartilage involvement and bone marrow edema should be considered part of the spectrum of associated MRI findings that can be encountered in this entity. Furthermore, the presented case shows that symptomatic dorsal patellar defects can be treated conservatively with success and that (decrease of) pain symptoms are likely related to (decrease of) bone marrow edema. (orig.)

  8. Contribution to the study of screw dislocations; Contribution a l'etude des dislocations helicoidales

    Energy Technology Data Exchange (ETDEWEB)

    Grilhe, J [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires

    1965-03-01

    The aim of this work is to study the germination, growth and properties of screw dislocations. In the introduction (first chapter), we describe briefly the main experimental results obtained by various authors (observations of screws by Amelinckx and Bontinck in ionic crystals, by Dash in silicon crystals and by Thomas and Whelan in aluminium based alloys). We then make a few considerations concerning characteristic geometry of screws and the various methods used for calculating the energy of a dislocation. In the second chapter we study the problems involving only slip of the screw around its cylinder. We calculate the equilibrium step as a function of the forces acting on the extremities. We determine the critical stress required to disrupt the screw and study the interactions between the screw and other dislocations of the lattice. In the third chapter we consider the problem of the stability when the dislocation can climb by absorption or emission of vacancies. We study separately the stability of the size which only involves volume diffusion and the stability of the shape which depends only on the rearrangement of the vacancies along the dislocation. In chapter four we put forward a germination model for the screws: since the vacancies are not absorbed by the screw dislocations, they form clusters which take up a spiral form. The formation of these spirals is studied from the geometrical point of view in face-centered cubic systems. In chapter five we make use of the results obtained in chapters two and three for studying the growth of the spirals. (author) [French] Le but de ce travail est d'etudier la germination, la croissance et les proprietes des dislocations helico ales. Dans l'introduction (premier chapitre), nous exposons brievement les principaux resultats experimentaux obtenus par differents auteurs (observations d'helice par Amelinckx et Bontinck dans les cristaux ioniques, par Dash dans des cristaux de silicium et par Thomas et Whelan dans des

  9. Automated estimation of hip prosthesis migration: a feasibility study

    Science.gov (United States)

    Vandemeulebroucke, Jef; Deklerck, Rudi; Temmermans, Frederik; Van Gompel, Gert; Buls, Nico; Scheerlinck, Thierry; de Mey, Johan

    2013-09-01

    A common complication associated with hip arthoplasty is prosthesis migration, and for most cemented components a migration greater than 0.85 mm within the first six months after surgery, are an indicator for prosthesis failure. Currently, prosthesis migration is evaluated using X-ray images, which can only reliably estimate migrations larger than 5 mm. We propose an automated method for estimating prosthesis migration more accurately, using CT images and image registration techniques. We report on the results obtained using an experimental set-up, in which a metal prosthesis can be translated and rotated with respect to a cadaver femur, over distances and angles applied using a combination of positioning stages. Images are first preprocessed to reduce artefacts. Bone and prosthesis are extracted using consecutive thresholding and morphological operations. Two registrations are performed, one aligning the bones and the other aligning the prostheses. The migration is estimated as the difference between the found transformations. We use a robust, multi-resolution, stochastic optimization approach, and compare the mean squared intensity differences (MS) to mutual information (MI). 30 high-resolution helical CT scans were acquired for prosthesis translations ranging from 0.05 mm to 4 mm, and rotations ranging from 0.3° to 3° . For the translations, the mean 3D registration error was found to be 0.22 mm for MS, and 0.15 mm for MI. For the rotations, the standard deviation of the estimation error was 0.18° for MS, and 0.08° for MI. The results show that the proposed approach is feasible and that clinically acceptable accuracies can be obtained. Clinical validation studies on patient images will now be undertaken.

  10. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  11. Golf hand prosthesis performance of transradial amputees.

    Science.gov (United States)

    Carey, Stephanie L; Wernke, Matthew M; Lura, Derek J; Kahle, Jason T; Dubey, Rajiv V; Highsmith, M Jason

    2015-06-01

    Typical upper limb prostheses may limit sports participation; therefore, specialized terminal devices are often needed. The purpose of this study was to evaluate the ability of transradial amputees to play golf using a specialized terminal device. Club head speed, X-factor, and elbow motion of two individuals with transradial amputations using an Eagle Golf terminal device were compared to a non-amputee during a golf swing. Measurements were collected pre/post training with various stances and grips. Both prosthesis users preferred a right-handed stance initially; however, after training, one preferred a left-handed stance. The amputees had slower club head speeds and a lower X-factor compared to the non-amputee golfer, but increased their individual elbow motion on the prosthetic side after training. Amputees enjoyed using the device, and it may provide kinematic benefits indicated by the increase in elbow flexion on the prosthetic side. The transradial amputees were able to swing a golf club with sufficient repetition, form, and velocity to play golf recreationally. Increased elbow flexion on the prosthetic side suggests a potential benefit from using the Eagle Golf terminal device. Participating in recreational sports can increase amputees' health and quality of life. © The International Society for Prosthetics and Orthotics 2014.

  12. Non-metallic implant for patellar fracture fixation: A systematic review.

    Science.gov (United States)

    Camarda, Lawrence; Morello, Salvatore; Balistreri, Francesco; D'Arienzo, Antonio; D'Arienzo, Michele

    2016-08-01

    Despite good clinical outcome proposals, there has been relatively little published regarding the use of non-metallic implant for patellar fracture fixation. The purpose of the study was to perform a systematic literature review to summarize and evaluate the clinical studies that described techniques for treating patella fractures using non-metallic implants. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until November 2015. The following search terms were used: patellar fracture, patella suture, patella absorbable, patella screw, patella cerclage. Two investigators independently reviewed all abstracts and the selection of these abstracts was then performed based on inclusion and/or exclusion criteria. A total of 9 studies involving 123 patients were included. Patients had a mean age of 33.7 years and were followed up for a mean of 18.9 months. The most common method for fracture fixations included the use of suture material. Good clinical outcomes were reported among all studies. Thirteen patients (10.5%) presented complications, while 4 patients (3.2%) required additional surgery for implant removal. There is a paucity of literature focused on the use of non-metallic implant for patellar fracture fixation. However, this systematic review showed that non-metallic implants are able to deliver good clinical outcomes reducing the rate of surgical complications and re-operation. These results may assist surgeons in choosing to use alternative material such as sutures to incorporate into their routine practice or to consider it, in order to reduce the rate of re-operation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. [Treatment of septic olecranon and patellar bursitis by excision and vacuum-assisted closure therapy].

    Science.gov (United States)

    Walter, G; Kemmerer, M; Hoffmann, R

    2013-08-01

    Treatment of septic olecranon and patellar bursitis differs considerably and is currently under discussion. We therefore performed a retrospective study of our patients with septic bursitis in the past 5 years. Between March 2007 and February 2012 we treated 79 patients with septic olecranon (n = 43) and patellar (n = 36) bursitis surgically: 61-males, 18 females, age 51 (range: 11-91) years. Four patients had not been treated before, 25 had suffered recurrences after 1-10 previous procedures, and 9 patients had not improved after conservative therapy. 34 patients presented with traumatic rupture or fistula of their bursae. In all cases we performed a radical bursectomy and vacuum-assisted therapy for 4 to 5 days. In addition, patients received systemic antibiotics. We phoned all patients and were successful in 57 cases (72 %). We questioned these patients for range of movement, limitations at work, pain, sensibility disorder, satisfaction with the result and further surgical procedures. In all cases we took tissue specimens for cultures, in 48 preparations histological examination was performed. Microbiological and histological results are discussed in detail. 40 patients were free of complaints, 15 complained of mild pain, 54 of 57 had unlimited range of motion. Minor discomforts at desk work were reported by 5 of 43 patients, 12 out of 36 patient reported discomfort when performing on their knees. There was no recurrence in the period of investigation. We recommend our treatment concept for septic olecranon and patellar bursitis because patient satisfaction is high and recurrences are reliably avoided. The soft tissue is spared, so that plastic covering procedures are seldom necessary. Georg Thieme Verlag KG Stuttgart · New York.

  14. Mechanism of Strain Rate Effect Based on Dislocation Theory

    International Nuclear Information System (INIS)

    Kun, Qin; Shi-Sheng, Hu; Li-Ming, Yang

    2009-01-01

    Based on dislocation theory, we investigate the mechanism of strain rate effect. Strain rate effect and dislocation motion are bridged by Orowan's relationship, and the stress dependence of dislocation velocity is considered as the dynamics relationship of dislocation motion. The mechanism of strain rate effect is then investigated qualitatively by using these two relationships although the kinematics relationship of dislocation motion is absent due to complicated styles of dislocation motion. The process of strain rate effect is interpreted and some details of strain rate effect are adequately discussed. The present analyses agree with the existing experimental results. Based on the analyses, we propose that strain rate criteria rather than stress criteria should be satisfied when a metal is fully yielded at a given strain rate. (condensed matter: structure, mechanical and thermal properties)

  15. Riemann–Cartan Geometry of Nonlinear Dislocation Mechanics

    KAUST Repository

    Yavari, Arash

    2012-03-09

    We present a geometric theory of nonlinear solids with distributed dislocations. In this theory the material manifold-where the body is stress free-is a Weitzenböck manifold, that is, a manifold with a flat affine connection with torsion but vanishing non-metricity. Torsion of the material manifold is identified with the dislocation density tensor of nonlinear dislocation mechanics. Using Cartan\\'s moving frames we construct the material manifold for several examples of bodies with distributed dislocations. We also present non-trivial examples of zero-stress dislocation distributions. More importantly, in this geometric framework we are able to calculate the residual stress fields, assuming that the nonlinear elastic body is incompressible. We derive the governing equations of nonlinear dislocation mechanics covariantly using balance of energy and its covariance. © 2012 Springer-Verlag.

  16. Gradients of geometrically necessary dislocations from white beam microdiffraction

    International Nuclear Information System (INIS)

    Barabash, R.I.; Ice, G.E.; Pang, J.W.L.

    2005-01-01

    Variations in the local crystallographic orientation due to the presence of geometrically necessary dislocations and dislocation boundaries smear the distribution of intensity near Laue reflections. Here, some simple model distributions of geometrically necessary dislocations, GNDs, are used to estimate the dislocation tensor field from the intensity distribution of Laue peaks. Streaking of the Laue spots is found to be quantitatively and qualitatively distinct depending on the ratio between the absorption coefficient and the GND density gradient. In addition, different slip systems cause distinctly different Laue-pattern streaking. Experimental Laue patterns are therefore sensitive to stored dislocations and GNDs. As an example, white beam microdiffraction was applied to characterize the dislocation arrangement in a deformed polycrystalline Ni grain during in situ uniaxial tension

  17. Chondropathia patellae - preoperative and postoperative demonstration of the patellar structure in plain roentgenography

    International Nuclear Information System (INIS)

    Schumacher, K.A.; Mutschler, W.; Bargon, G.

    1982-01-01

    The study is based on 86 patients surgically treated for chondromalacia patellae, who in a 2 year follow-up were controlled by defile-radiographs and clinical examination. While there was an improvement of all clinical symptoms examined, no significant change in the radiologic appearance of the patellar structure was observed as compared with the pre-operative status. This includes that neither significant changes indicating development of arthrosis nor aggravation of pre-existing arthrotic lesions could be found. However, it is commonly suggested from roentgenographic findings with type 3 lesions, that severe chondromalacia patellae may be a precursor of osteoarthrosis. (orig.) [de

  18. Evaluation of patellar chondromalacia with MR: comparison between T2-weighted FSE SPIR and GE MTC.

    Science.gov (United States)

    Macarini, Luca; Perrone, Alessandra; Murrone, Mario; Marini, Stefania; Stefanelli, Michele

    2004-09-01

    To compare two different MR sequences to tissue signal suppression in the study of patellar cartilage abnormalities. We examined 26 patients with magnetic resonance (MR) imaging: sequences included spectral presaturation with inversion recovery (SPIR), with fat suppression and T2-weighted images, magnetization transfer contrast (MTC) sequences, T1-weighted and T2-weighted spin-echo sequences. All patients underwent conventional knee arthroscopy and in all patients a hyaline cartilage lesion was assessed in three articular zones: the patellar medial facet, the lateral facet and the patellar crista. Was assessed 78 articular facets. The lesions were classified using a standard arthroscopic grading system adapted to MR imaging: normal cartilage that corresponds to the grade 0 according to the Noyes grading system, low grade lesions that correspond to the grade I e IIa and high grade lesions that correspond to grades IIb and III. The arthroscopic results were compared with MR images. We assessed the MR diagnostic accuracy, sensitivity, specificity and MR positive predictive value and negative predictive value of the two sequences taking into consideration total lesions, and high-grade and low grade lesions separately. Twenty-four low grade lesions (16 grade I e 8 grade IIa) and 18 high grade lesions (10 grade IIb e 8 grade III) were diagnosed by arthroscopy. Regarding low grade and high-grade lesions together, the accuracy was 77% for MTC sequences and 90% for SPIR sequences. In identifying low-grade lesions, the sensitivity was 88% for SPIR sequence and 42% for MTC sequences. Specificity for the detection of all lesions was 89% for the SPIR sequences and 94% for the MTC sequences. The SPIR sequence visualised water content abnormalities in degenerating cartilage, which are representative of low-grade lesions. The sensitivity of the sequence enabled us to obtain improved contrast for detecting cartilage surface irregularities. The MTC sequences allowed us to grade high

  19. Effect of prostaglandin E2 injection on the structural properties of the rat patellar tendon

    Directory of Open Access Journals (Sweden)

    Ferry Scott T

    2012-01-01

    Full Text Available Abstract Background Increased tendon production of the inflammatory mediator prostaglandin E2 (PGE2 has been suggested to be a potential etiologic agent in the development of tendinopathy. Repeated injection of PGE2 into tendon has been proposed as a potential animal model for studying treatments for tendinopathy. In contrast, nonsteroidal anti-inflammatory drugs (NSAIDs which inhibit PGE2 production and are commonly prescribed in treating tendinopathy have been shown to impair the healing of tendon after acute injury in animal models. The contradictory literature suggests the need to better define the functional effects of PGE2 on tendon. Our objective was to characterize the effects of PGE2 injection on the biomechanical and biochemical properties of tendon and the activity of the animals. Our hypothesis was that weekly PGE2 injection to the rat patellar tendon would lead to inferior biomechanical properties. Methods Forty rats were divided equally into four groups. Three groups were followed for 4 weeks with the following peritendinous injection procedures: No injection (control, 4 weekly injections of saline (saline, 4 weekly injections of 800 ng PGE2 (PGE2-4 wks. The fourth group received 4 weekly injections of 800 ng PGE2 initially and was followed for a total of 8 weeks. All animals were injected bilaterally. The main outcome measurements included: the structural and material properties of the patellar tendon under tensile loading to failure, tendon collagen content, and weekly animal activity scores. Results The ultimate load of PGE2-4 wks tendons at 4 weeks was significantly greater than control or saline group tendons. The stiffness and elastic modulus of the PGE2 injected tendons at 8 weeks was significantly greater than the control or saline tendons. No differences in animal activity, collagen content, or mean fibril diameter were observed between groups. Conclusions Four weekly peritendinous injections of PGE2 to the rat patellar

  20. The impact of patellar tendinopathy on sports and work performance in active athletes

    OpenAIRE

    De Vries, Astrid J; Koolhaas, Wendy; Zwerver, Johannes; Diercks, Ron L.; Nieuwenhuis, Kari; Van Der Worp, Henk; Brouwer, Sandra; Van Den Akker-Scheek, Inge

    2017-01-01

    Greater insight into sports and work performance of athletes with patellar tendinopathy (PT) will help establish the severity of this common overuse injury. Primary aim of this study is to investigate the impact of PT on sports and work performance. Seventy seven active athletes with PT (50 males; age 28.1 +/- 8.2years; Victorian Institute of Sports Assessment Patella 56.4 +/- 12.3) participated in this survey. Sports performance, work ability and work productivity were assessed using the Osl...