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Sample records for carpi ulnaris muscle

  1. Duplication of the extensor carpi ulnaris tendon.

    Science.gov (United States)

    Barfred, T; Adamsen, S

    1986-05-01

    Three cases are presented, in which an anomalous tendon slip between the extensor carpi ulnaris tendon and the extensor apparatus of the fifth finger was found. One of the patients was a violinist, who had serious impairment of the left wrist joint and the small finger due to the anomaly. The symptoms disappeared after excision.

  2. Flexor carpi ulnaris tenotomy alone does not eliminate its contribution to wrist torque

    NARCIS (Netherlands)

    M. de Bruin; M.J.C. Smeulders; M. Kreulen

    2011-01-01

    Background: Flexor carpi ulnaris muscle tenotomy and transfer to the extensor side of the wrist are common procedures used to improve wrist position and dexterity in patients with cerebral palsy. Our aim was to determine whether this muscle still influences wrist torque even after tenotomy of its di

  3. Deoxygenation and the blood volume signals in the flexor carpi ulnaris and radialis muscles obtained during the execution of the Mirallas's test of judo athletes

    Science.gov (United States)

    Verdaguer-Codina, Joan; Mirallas, Jaume A.

    1996-12-01

    The technique of execution of any movement in Judo is extremely important. The coaches want tests and tools easy to use and cheaper, to evaluate the progress of a judoist in the tatame. In this paper we present a test developed by Mirallas, which has his name 'Test of Mirallas' to evaluate the maximal power capacity of the judoist. The near infrared spectroscopy (NIRS) signals were obtained to have a measurement of the metabolic work of the flexor carpi ulnaris and radialis muscles, during the execution of the ippon-seoi-nage movement, allowing this measurement to assess by NIRS the maximal oxygen uptake. Also obtained were tympanic, skin forehead, and biceps brachii temperatures during the test time and recovery phase to study the effects of ambient conditions and the post-exercise oxygen consumption. The deoxygenation and blood volume signals obtained gave different results, demonstrating the hypothesis of the coaches that some judoist do the execution of the ippon-seoi-nage movement correctly and the rest didn't. The heart rate frequency obtained in the group of judoist was between 190-207 bpm, and in the minute five of post-exercise was 114-137 bpm; the time employed in the MIrallas's test were from 7 feet 14 inches to 13 feet 49 inches, and the total of movements were from 199 to 409. The data obtained in the skin forehead, and skin biceps brachii confirms previous works that the oxygen consumption remains after exercise in the muscle studied. According to the results, the test developed by Mirallas is a good tool to evaluate the performance of judoist any time, giving better results compared with standard tests.

  4. Ultrasound of Extensor Carpi Ulnaris Tendon Subluxation in a Tennis Player.

    Science.gov (United States)

    Spicer, Paul J; Romesberg, Amanda; Kamineni, Srinath; Beaman, Francesca D

    2016-06-01

    Wrist pain is common among competitive tennis players. Subluxation of the extensor carpi ulnaris (ECU) tendon has gained recognition as a cause of ulnar-side wrist pain in athletes. In tennis, the wrist is forcibly flexed, supinated, and ulnar deviated. These repetitive motions stress the ECU tendon stabilizers allowing tendon subluxation from the ulnar groove, especially in cases of anatomic variations such as a shallow groove. We present the presurgical and postsurgical imaging findings of recurrent ECU tendon subluxation in an elite tennis player.

  5. Long-term follow-up of the flexor carpi ulnaris transfer in spastic hemiplegic children.

    Science.gov (United States)

    Thometz, J G; Tachdjian, M

    1988-01-01

    A retrospective study was performed on 25 patients with cerebral palsy who underwent transfer of the flexor carpi ulnaris to the radial wrist extendors. The mean age at the time of surgery was 8 years 1 month. The mean follow-up was 8 years 7 months. At follow-up, the mean active wrist dorsiflexion was 44.2 degrees, palmar flexion was 19.0 degrees, supination was 40.2 degrees, and pronation was 53.4 degrees. According to a modification of Green's evaluation system, there were six excellent, nine good, five fair, and five poor results. Two patients required further surgery to correct a supination, dorsiflexion contracture. We found the transfer to be quite effective in improving wrist dorsiflexion, although there was often a significant loss of active palmar flexion postoperatively. The patient therefore should have good digital extension (with the wrist extended passively above neutral) to be considered for the transfer.

  6. Acute calcific tendinitis of the flexor carpi ulnaris causing acute compressive neuropathy of the ulnar nerve: a case report.

    Science.gov (United States)

    Yasen, Sam

    2012-12-01

    This study reports a case of acute calcific tendinitis of the flexor carpi ulnaris in a 64-year-old woman. She presented with symptoms of acute ulnar nerve compression mimicking a volar compartment syndrome. Owing to rapidly progressive symptoms, emergency surgical exploration was carried out. Intra-operatively a large mass of calcium phosphate carbonate was noted in association with the flexor carpi ulnaris near its insertion at the wrist compressing the ulnar nerve and artery in Guyon's canal. Postoperatively the patient had complete resolution of symptoms. Conservative management with non-steroidal anti-inflammatory drugs, rest, splinting, and steroid therapy is recommended for acute calcific tendinitis, but this case suggests a role for surgical treatment when there is acute neural compression and severe pain.

  7. The extensor carpi ulnaris pseudolesion: evaluation with microCT, histology, and MRI

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    Ali, Sayed; Cunningham, Ryan; Mohamed, Feroze [Temple University Hospital, Department of Radiology, Philadelphia, PA (United States); Amin, Mamta; Popoff, Steven N.; Barbe, Mary F. [Temple University School of Medicine, Department of Anatomy, Philadelphia, PA (United States)

    2015-12-15

    To determine if magic angle plays a role in apparent central increased signal intensity of the distal extensor carpi ulnaris tendon (ECU) on MRI, to see if histologic findings of tendon degeneration are associated with increased T1 or T2 tendon signal on MR imaging, and to determine the prevalence of the ECU ''pseudolesion''. A standard 3 Tesla protocol was utilized to scan ten cadaveric wrists. A 40 mm length of 10 ECU and four extensor carpi radialis brevis (ECRB) tendons were immersion fixed before microCT scanning. Staining with Alcian blue, Masson's trichrome and Safranin O was performed before light microscopy. Fifty clinical wrist MRIs were also reviewed for the presence of increased T1 and/or T2 signal. Central increased T1 and/or T2 signal was observed in 9 of 10 cadaveric ECU tendons, but not in ECRB tendons. MicroCT and histology showed inter-tendinous matrix between the two distal heads of the ECU. Increased mucoid degeneration correlated with increased MRI signal intensity. The tendon fibers were at a maximum of 8.39 to the longitudinal axis on microCT. Clinical MRIs showed increased T1 signal in 6 %, increased T2 signal in 8 %, increased T1 and T2 signal in 80 %, and 6 % showing no increased signal. Central increased T1 and/or T2 signal in the ECU tendon indicates the presence of normal inter-tendinous ground substance, with increased proteoglycan content (mucoid degeneration) responsible for increased signal intensity. None of the fibers were shown on microCT to approach the magic angle. (orig.)

  8. Modification of the Sauvé-Kapandji procedure with extensor carpi ulnaris tenodesis.

    Science.gov (United States)

    Minami, A; Kato, H; Iwasaki, N

    2000-11-01

    The Sauvé-Kapandji procedure is a useful treatment option for osteoarthritis of the distal radioulnar joint. Recent reports of a painful unstable proximal ulnar stump prompted us to develop a method of stabilizing the proximal stump of the ulna during the Sauvé-Kapandji procedure by using a half-slip of the extensor carpi ulnaris. Thirteen osteoarthritic wrists (8 primary and 5 traumatic) in 8 men and 5 women with an average age of 50 years were treated by this method. The length of the follow-up periods averaged 36 months. Pain improved in all patients after surgery but pain was elicited over 1 ulnar stump by direct pressure. Both pronation/supination and flexion/extension had statistically significant improvement with the exception of flexion. Grip strength improved in all wrists after surgery. Postoperative x-rays improved alignment in both coronal and lateral planes. Stabilization of the proximal ulnar stump associated with Sauvé-Kapandji procedure is a useful procedure to prevent an unstable ulnar stump in the treatment of osteoarthritis of the distal radioulnar joint.

  9. Anatomical study of the musculus deltoideus and musculus flexor carpi ulnaris in 3 species of wild birds.

    Science.gov (United States)

    Canova, Marco; Bedoni, Carla; Harper, Valeria; Rambaldi, Anna Maria; Bombardi, Cristiano; Grandis, Annamaria

    2016-01-01

    Given the limited information regarding the anatomy of the thoracic limb in European avian species, we decided to investigate the related muscles in the grey heron (Ardea cinerea), in the eurasian buzzard (Buteo buteo), and in the common kestrel (Falco tinnunculus). Therefore we performed a stratigraphic dissection of the wing in 3 subjects. The pars major and minor of the musculus deltoideus, despite being roughly in line with those reported by other authors in other species, displayed unique features. Concerning the pars propatagialis of the musculus deltoideus, from what was observed in the grey heron, we believe this structure can contribute to maintain the propatagial tension. In this way vibrations of this structure, which could cause diminished lift, are avoided. Moreover the peculiarity evidenced in the distal insertion of the common kestrel could influence the control of the pronation-supination of the wing during hovering. With respect to the musculus flexor carpi ulnaris, we believe the presence of a sesamoid-like structure at the base tendon, found in the grey heron and in the eurasian buzzard, may help complete the articular surfaces of the elbow. This study shows interesting data on species not previously examined and provides a possible functional correlation between the peculiarity observed and the kind of flight of each species.

  10. Association between distal ulnar morphology and extensor carpi ulnaris tendon pathology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Connie Y.; Huang, Ambrose J.; Bredella, Miriam A.; Kattapuram, Susan V.; Torriani, Martin [General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts, Boston, MA (United States)

    2014-06-15

    The purpose of this study was to evaluate the association between distal ulnar morphology and extensor carpi ulnaris (ECU) tendon pathology. We retrospectively reviewed 71 adult wrist MRI studies with ECU tendon pathology (tenosynovitis, tendinopathy, or tear), and/or ECU subluxation. Subjects did not have a history of trauma, surgery, infection, or inflammatory arthritis. MRI studies from 46 subjects without ECU tendon pathology or subluxation were used as controls. The following morphological parameters of the distal ulna were measured independently by two readers: ulnar variance relative to radius, ulnar styloid process length, ECU groove depth and length. Subjects and controls were compared using Student's t test. Inter-observer agreement (ICC) was calculated. There was a significant correlation between negative ulnar variance and ECU tendon pathology (reader 1 [R1], P = 0.01; reader 2 [R2], P < 0.0001; R1 and R2 averaged data, P < 0.0001) and ECU tendon subluxation (P = 0.001; P = 0.0001; P < 0.0001). In subjects with ECU tendon subluxation there was also a trend toward a shorter length (P = 0.3; P <0.0001; P = 0.001) and a shallower ECU groove (P = 0.01; P = 0.03; P = 0.01; R1 and R2 averaged data with Bonferroni correction, P = 0.08). ECU groove depth (P = 0.6; P = 0.8; P = 0.9) and groove length (P = 0.1; P = 0.4; P = 0.7) showed no significant correlation with ECU tendon pathology, and length of the ulnar styloid process showed no significant correlation with ECU tendon pathology (P = 0.2; P = 0.3; P = 0.2) or subluxation (P = 0.4; P = 0.5; P = 0.5). Inter-observer agreement (ICC) was >0.64 for all parameters. Distal ulnar morphology may be associated with ECU tendon abnormalities. (orig.)

  11. Stabilization of the Proximal Ulnar Stump after the Darrach or Sauvé-Kapandji Procedure by Using the Extensor Carpi Ulnaris Tendon

    OpenAIRE

    Chu, Po-Jung; Lee, Hung-Maan; Hung, Sheng-Tsai; Shih, Jui-Tien

    2008-01-01

    The Darrach and Sauvé-Kapandji procedures are considered to be useful treatment options for distal radioulnar joint disorders. Postoperative instability of the proximal ulnar stump and radioulnar convergence, however, may cause further symptoms. From October 1999 to May 2002, a total of 19 wrists in 15 men and four women, with an average age of 48.3 years, were treated by stabilizing the proximal ulnar stump with a half-slip of the extensor carpi ulnaris tendon using modified Darrach and Sauv...

  12. Stabilization of the proximal ulnar stump after the Darrach or Sauvé-Kapandji procedure by using the extensor carpi ulnaris tendon.

    Science.gov (United States)

    Chu, Po-Jung; Lee, Hung-Maan; Hung, Sheng-Tsai; Shih, Jui-Tien

    2008-12-01

    The Darrach and Sauvé-Kapandji procedures are considered to be useful treatment options for distal radioulnar joint disorders. Postoperative instability of the proximal ulnar stump and radioulnar convergence, however, may cause further symptoms. From October 1999 to May 2002, a total of 19 wrists in 15 men and four women, with an average age of 48.3 years, were treated by stabilizing the proximal ulnar stump with a half-slip of the extensor carpi ulnaris tendon using modified Darrach and Sauvé-Kapandji procedures. The average follow-up period was 77 months (range, 62 to 91 months). No patient complained of symptoms due to instability of the proximal ulnar stump. Grip strength improved in all wrists after surgery. Postoperative X-rays, including loading X-rays, showed improved alignment in both coronal and lateral planes. We concluded that stabilization of the proximal ulnar stump with ECU tenodesis is an effective procedure for treating distal radioulnar joint disorder after the Darrach and Sauvé-Kapandji procedures.

  13. Reliability of In Vivo Determination of Forearm Muscle Volume Using 3.0 T Magnetic Resonance Imaging

    NARCIS (Netherlands)

    M.J.C. Smeulders; S. van den Berg; J. Oudeman; A.J. Nederveen; M. Kreulen; M. Maas

    2010-01-01

    Purpose: To apply magnetic resonance imaging (MRI) as a tool for quantifying muscle volume of forearm muscles feasibility and reliability of volume estimation of the flexor carpi ulnaris (FCU) and the extensor carpi ulnaris (ECU). Materials and Methods: Forearms of 10 subjects were scanned twice. Mu

  14. Anticipatory and Reactive Response to Falls: Muscle Synergy Activation of Forearm Muscles.

    Science.gov (United States)

    Couzens, Greg; Kerr, Graham

    2015-10-01

    We investigated the surface electromyogram response of six forearm muscles to falls onto the outstretched hand. The extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris, abductor pollicis longus, flexor carpi radialis and flexor carpi ulnaris muscles were sampled from eight volunteers who underwent ten self-initiated falls. All muscles initiated prior to impact. Co-contraction is the most obvious surface electromyogram feature. The predominant response is in the radial deviators. The surface electromyogram timing we recorded would appear to be a complex anticipatory response to falling modified by the effect on the forearm muscles following impact. The mitigation of the force of impact is probably more importantly through shoulder abduction and extension and elbow flexion rather than action of the forearm muscles.

  15. [An accessory muscle and additional variants of the forearm].

    Science.gov (United States)

    Arnold, G; Zech, M

    1977-01-01

    A report is given on an accessory muscle of the forearm. The muscle originates from the medial epicondyle and the fascia of the forearm and inserts into the pisiform bone and retinaculum. The accessory muscle has a great similarity with the flexor carpi ulnaris muscle.

  16. Anatomía arterial de los colgajos musculares de extensor carpi radialis longus y extensor carpi radialis brevis para su uso en transferencia muscular funcional libre Arterial anatomy of the extensor carpi radialis longus and extensor carpi radialis brevis muscle flaps related to its use in free functioning muscle transfer

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    A. Rodríguez Lorenzo

    2008-09-01

    ón anatómica del nervio radial con el pedículo del ECRL hace que no sea posible su transferencia como colgajo libre sin sacrificar la rama motora del nervio radial en la mayor parte de los casos.The arterial anatomy of the Extensor Carpi Radialis Longus and Brevis (ECRL, ECRB flaps is herein described in order to provide the vascular basis to be used as free muscle transfer for facial reanimation. We used 29 fresh above-elbow human arms injected by means of two diferent techniques.Latex-injection was performed in 18 arms and the modified lead oxide-gelatine injection technique was performed in 11 arms. The ECRL and ECRB with their pedicles were dissected, photodocumented and radiographied.The number, length and calibers of the muscle pedicles were recorded. The intramuscular vascular pattern and the relations of the main pedicles of the muscles with the radial nerve were also noted. Two vascular patterns were found following the Mathes and Nahai Classification of the Vascular Anatomy of the Muscles (number of pedicles and its dominance: Type I (37,9% of ECRL and 20,7% of ECRB dissections and Type II (62,1% of ECRL and 79,3% of ECRB dissections. The dominant pedicle for the ECRL (with an average caliber of 1,73 mm and an average length of pedicle of 32,32 mm is a branch of the radial recurrent artery in 100% of the dissections and the dominant pedicle for the ECRB (with an average caliber of 1,11 mm and an average length of pedicle of 27,77 mm a branch of the radial artery in 68,9% of the dissections and a branch of radial recurrent artery in 31,1% of the cases. As a conclusion, ECRL and ECRB muscle flaps present two types of vascular patterns: type I and type II.Type II pattern is the most common in our study. The anatomical features of both muscles (vascular basis,presence of an important fascial layer, contour and length of the muscle, make them reliable as free muscles flaps for facial reanimation, however, the relation between the dominant pedicle for the ECRL

  17. Comparison of EMG during passive stretching and shortening phases of each muscle for the investigation of parkinsonian rigidity.

    Science.gov (United States)

    Kwon, Yuri; Kim, Ji-Won; Kim, Ji-Sun; Koh, Seong-Beom; Eom, Gwang-Moon; Lim, Tae-Hong

    2015-01-01

    The aim of this study was to test the hypothesis in the literature that torque resistance of parkinsonian rigidity is the difference between the independent contributions of stretched and shortened muscles. The hypothesis was tested using muscle-specific stretch-shortening (MSSS) EMG ratio in this study. Nineteen patients with idiopathic Parkinson's disease (PD) and 18 healthy subjects (the mean age comparable to that of patients) participated in this study. The EMG activity was measured in the four muscles involved in wrist joint movement, i.e. flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis and extensor carpi ulnaris. The passive flexion-extension movement with a range of ±30∘ was applied at wrist joint. Root mean squared (RMS) mean was calculated from the envelope of the EMG for each of stretching and shortening phases. MSSS EMG ratio was defined as the ratio of RMS EMG of stretching phase and RMS EMG of shortening phase of a single muscle, and it was calculated for each muscle. MSSS EMG ratios were smaller than one in all muscles. These results indicate that all wrist muscles generate greater mean EMG during shortening than during stretching. Therefore, the torque resistance of parkinsonian rigidity cannot be explained as the simple summation of independent antagonistic torque pair.

  18. Architectural properties of the neuromuscular compartments in selected forearm skeletal muscles.

    Science.gov (United States)

    Liu, An-Tang; Liu, Ben-Li; Lu, Li-Xuan; Chen, Gang; Yu, Da-Zhi; Zhu, Lie; Guo, Rong; Dang, Rui-Shan; Jiang, Hua

    2014-07-01

    The purposes f this study were to (i) explore the possibility of splitting the selected forearm muscles into separate compartments in human subjects; (ii) quantify the architectural properties of each neuromuscular compartment; and (iii) discuss the implication of these properties in split tendon transfer procedures. Twenty upper limbs from 10 fresh human cadavers were used in this study. Ten limbs of five cadavers were used for intramuscular nerve study by modified Sihler's staining technique, which confirmed the neuromuscular compartments. The other 10 limbs were included for architectural analysis of neuromuscular compartments. The architectural features of the compartments including muscle weight, muscle length, fiber length, pennation angle, and sarcomere length were determined. Physiological cross-sectional area and fiber length/muscle length ratio were calculated. Five of the selected forearm muscles were ideal candidates for splitting, including flexor carpi ulnaris, flexor carpi radials, extensor carpi radialis brevis, extensor carpi ulnaris and pronator teres. The humeral head of pronator teres contained the longest fiber length (6.23 ± 0.31 cm), and the radial compartment of extensor carpi ulnaris contained the shortest (2.90 ± 0.28 cm). The ulnar compartment of flexor carpi ulnaris had the largest physiological cross-sectional area (5.17 ± 0.59 cm(2)), and the ulnar head of pronator teres had the smallest (0.67 ± 0.06 cm(2)). Fiber length/muscle length ratios of the neuromuscular compartments were relatively low (average 0.27 ± 0.09, range 0.18-0.39) except for the ulnar head of pronator teres, which had the highest one (0.72 ± 0.05). Using modified Sihler's technique, this research demonstrated that each compartment of these selected forearm muscles has its own neurovascular supply after being split along its central tendon. Data of the architectural properties of each neuromuscular compartment provide insight into the 'design' of their

  19. Further insights into post-exercise effects on H-reflexes and motor evoked potentials of the flexor carpi radialis muscles.

    Science.gov (United States)

    Kato, Takashi; Takeda, Yusaku; Tsuji, Toshio; Kasai, Tatsuya

    2003-01-01

    The present study investigated the relative contribution of the cortical and spinal mechanisms for post-exercise excitability changes in human motoneurons. Seven healthy right-handed adults with no known neuromuscular disabilities performed an isometric voluntary wrist flexion at submaximum continuous exertion. After the subjects continued muscle contraction until volitional fatigue, the H-reflexes induced by an electric stimulation and motor evoked potentials (MEPs) induced by a transcranial magnetic stimulation (TMS) from a flexor carpi radialis (FCR) muscle were recorded 7 times every 20 s. The H-reflex was used to assess excitability changes at the spinal level, and the MEP was used to study excitability changes at the cortical level. Hreflexes showed a depression (30% of control value) soon after the cessation of wrist flexion and recovered with time thereafter. On the other hand, an early (short latency) MEP showed facilitation immediately after the cessation of wrist flexion (50% of control value) and thereafter decreased. A possible mechanism for the contradictory results of the 2 tests, in spite of focusing on the same motoneuron pool, might be the different test potential sizes between them. In addition, a late (long latency) MEP response appeared with increasing exercise. With regard to the occurrence of late MEP response, a central mechanism may be proposed to explain the origin-that is, neural pathways with a high threshold that do not participate under normal circumstances might respond to an emergency level of muscle exercise, probably reflecting central effects of fatigue.

  20. A Case of Reverse Palmaris Longus Muscle- An Additional Muscle in the Anterior Compartment of the Forearm

    Science.gov (United States)

    Bhat, Ashwini Lagadamane Sathynarayana; Gadahad, Mohandas Rao Kappettu

    2016-01-01

    It is uncommon to have additional muscles in the upper limb. Some of them may restrict the movements or compress the nerves and vessels, while others may go unnoticed. During the routine dissection for undergraduate medical students, we observed an additional muscle in the anterior compartment of the forearm in about 60-year-old male cadaver. The muscle had a prominent belly and a long tendon. Distally, it was attached to the flexor retinaculum by a short and thick tendon. Proximally, long tendon of the muscle passed between the flexor carpi ulnaris and palmaris longus and was attached to the common aponeurosis shared by the extensor carpi ulnaris and flexor digitorum profundus muscles. The additional muscle belly was supplied by a branch from the anterior interosseous nerve. The ulnar nerve and artery was passing deep to the fleshy belly of the muscle. The muscle reported here might compress the ulnar nerve and artery and may produce neurovascular symptoms. On the other hand, the tendon and fleshy belly of the muscle could be useful in muscle/tendon grafts. The observations made by us in the present case will supplement our knowledge of variations of the muscles in this region which could be useful for surgeons during the forearm and hand surgeries. PMID:27134851

  1. Electromyographical Study on Muscle Fatigue in Repetitive Forearm Tasks

    Institute of Scientific and Technical Information of China (English)

    DAI Wentao; ZHAO Xiaorong; WANG Zhenglun; YANG Lei

    2007-01-01

    The purpose of this study was to examine whether repetitive muscle tasks in low weight load might influence the fatigue of forearm muscles, and to identify ergonomic risk factors of forearm muscle fatigue in these tasks. Sixteen healthy male volunteers performed eight wrist extensions in different frequency, weight and angle loads while being instructed to keep a dominant upper limb posture as constant as possible. Surface electromyograph (sEMG) was recorded from right extensors digitorium (ED), flexor carpi radialis (FCR), flexor carpi ulnaris (FCU) and extensor carpi ulnaris (ECU) during the task performance. Our results showed that mean power frequency (MPF) and median frequency (MF) values of ED, FCR and FCU were significantly lower (P<0.05) at high frequency load level than at low load level. However, MPF and MF values of ED were significantly lower (P<0.01) in higher load groups of frequency, angle and weight than in lower load groups. These results indicated that the fatigue of muscles varied in the same task, and the number-one risk factor of ECU, ED and FCR was angle load.

  2. Facilitation from hand muscles innervated by the ulnar nerve to the extensor carpi radialis motoneurone pool in humans: a study with an electromyogram-averaging technique.

    Science.gov (United States)

    Suzuki, Katsuhiko; Ogawa, Keiichi; Sato, Toshiaki; Nakano, Haruki; Fujii, Hiromi; Shindo, Masaomi; Naito, Akira

    2012-10-01

    Effects of low-threshold afferents of hand muscles innervated by the ulnar nerve on an excitability of the extensor carpi radialis (ECR) motoneurone pool in humans were examined using an electromyogram-averaging (EMG-A) technique. Changes of EMG-A of ECR exhibiting 10% of the maximum contraction by electrical stimulation to the ulnar nerve at the wrist (ES-UN) and mechanical stimulation to the hypothenar muscles (MS-HTM) and first dorsal interosseus (MS-FDI) were evaluated in eight normal human subjects. The ES-UN with the intensity immediately below the motor threshold and MS-HTM and -FDI with the intensity below the threshold of the tendon(T)-reflex were delivered. Early and significant peaks in EMG-A were produced by ES-UN, MS-HTM, and MS-FDI in eight of eight subjects. The mean amplitudes of the peaks by ES-UN, MS-HTM, and MS-FDI were, respectively, 121.9%, 139.3%, and 149.9% of the control EMG (100%). The difference between latencies of the peaks by ES-UN and MS-HTM, and ES-UN and MS-FDI was almost equivalent to that of the Hoffmann(H)- and T-reflexes of HTM and FDI, respectively. The peaks by ES-UN, MS-HTM, and MS-FDI diminished with tonic vibration stimulation (TVS) to HTM and FDI, respectively. These findings suggest that group Ia afferents of the hand muscles facilitate the ECR motoneurone pool.

  3. Berengario da Carpi.

    Science.gov (United States)

    De Santo, N G; Bisaccia, C; De Santo, L S; De Santo, R M; Di Leo, V A; Papalia, T; Cirillo, M; Touwaide, A

    1999-01-01

    Berengario da Carpi was magister of anatomy and surgery at the University of Bologna from 1502 to 1527. Eustachio and Falloppia defined him as 'the restaurator of anatomy'. He was a great surgeon, anatomist and physician of illustrious patients including Lorenzo II dei Medici, Giovanni dalle Bande Nere, Galeazzo Pallavicini, Cardinal Colonna, and Alessandro Soderini. He had strong links to the intellectuals of his time (Forni, Bonamici, Manuzio, Pomponazzi) as well as with the Medici family. He was respected by the Popes Julius II, Leo X and Clement VII. His main contributions are the Isogogae Breves, De Fractura calvae sive cranei, and the illustrated Commentaria on the Anatomy of Mondino de Liucci, a textbook utilized for more than 200 years, which Berengario aimed to restore to its initial text. The Commentaria constitutes the material for the last part of this paper which concludes with a personal translation of some passages on 'The kidney', where the author gives poignant examples of experimental ingenuity.

  4. Determining physiological cross-sectional area of extensor carpi radialis longus and brevis as a whole and by regions using 3D computer muscle models created from digitized fiber bundle data.

    Science.gov (United States)

    Ravichandiran, Kajeandra; Ravichandiran, Mayoorendra; Oliver, Michele L; Singh, Karan S; McKee, Nancy H; Agur, Anne M R

    2009-09-01

    Architectural parameters and physiological cross-sectional area (PCSA) are important determinants of muscle function. Extensor carpi radialis longus (ECRL) and brevis (ECRB) are used in muscle transfers; however, their regional architectural differences have not been investigated. The aim of this study is to develop computational algorithms to quantify and compare architectural parameters (fiber bundle length, pennation angle, and volume) and PCSA of ECRL and ECRB. Fiber bundles distributed throughout the volume of ECRL (75+/-20) and ECRB (110+/-30) were digitized in eight formalin embalmed cadaveric specimens. The digitized data was reconstructed in Autodesk Maya with computational algorithms implemented in Python. The mean PCSA and fiber bundle length were significantly different between ECRL and ECRB (p < or = 0.05). Superficial ECRL had significantly longer fiber bundle length than the deep region, whereas the PCSA of superficial ECRB was significantly larger than the deep region. The regional quantification of architectural parameters and PCSA provides a framework for the exploration of partial tendon transfers of ECRL and ECRB.

  5. Effects of tendon and muscle belly dissection on muscular force transmission following tendon transfer in the rat

    NARCIS (Netherlands)

    Maas, H.; Huijing, P.A.J.B.M.

    2012-01-01

    The aim of the present study was to quantify to what extent the scar tissue formation following the transfer of flexor carpi ulnaris (FCU) to the distal tendon of extensor carpi radialis (ECR) affects the force transmission from transferred FCU in the rat. Five weeks after recovery from surgery (ten

  6. Median and ulnar nerve compression at the wrist caused by anomalous muscles.

    Science.gov (United States)

    De Smet, L

    2002-12-01

    Compression of the median and ulnar nerves at the wrist is frequently encountered. Carpal tunnel syndrome usually occurs without any obvious extrinsic cause; several cases have however been reported caused by anomalous or hypertrophic muscles. A survey of the literature shows that compression neuropathy of the median nerve has been reported in relation with anomalies affecting three muscles: the first (or second) lumbrical, the palmaris longus and its anatomic variants and the superficial flexor of the index finger. In the ulnar tunnel the situation is thoroughly different: so-called idiopathic ulnar tunnel syndrome is rare and an extrinsic compressing structure can usually be disclosed. Anomalous muscles belong to the palmaris longus/abductor digiti minimi group; the flexor carpi ulnaris is sometimes involved. One can suspect the presence of such an anomalous muscle when the compression syndrome concerns a patient who is not within the "usual" age group with symptoms initiated or aggravated by physical exercise.

  7. Characterization of focal muscle compression under impact loading

    Science.gov (United States)

    Butler, B. J.; Sory, D. R.; Nguyen, T.-T. N.; Proud, W. G.; Williams, A.; Brown, K. A.

    2017-01-01

    In modern wars over 70% of combat wounds are to the extremities. These injuries are characterized by disruption and contamination of the limb soft tissue envelope. The extent of this tissue trauma and contamination determine the outcome of the extremity injury. In military injury, common post-traumatic complications at amputation sites include heterotopic ossification (formation of bone in soft tissue), and severe soft tissue and bone infections. We are currently developing a model of soft tissue injury that recreates pathologies observed in combat injuries. Here we present characterization of a controlled focal compression of the rabbit flexor carpi ulnaris (FCU) muscle group. The FCU was previously identified as a suitable site for studying impact injury because its muscle belly can easily be mobilized from the underlying bone without disturbing anatomical alignment in the limb. We show how macroscopic changes in tissue organization, as visualized using optical microscopy, can be correlated with data from temporally resolved traces of loading conditions.

  8. Flexible adaptation to an artificial recurrent connection from muscle to peripheral nerve in man.

    Science.gov (United States)

    Kato, Kenji; Sasada, Syusaku; Nishimura, Yukio

    2016-02-01

    Controlling a neuroprosthesis requires learning a novel input-output transformation; however, how subjects incorporate this into limb control remains obscure. To elucidate the underling mechanisms, we investigated the motor adaptation process to a novel artificial recurrent connection (ARC) from a muscle to a peripheral nerve in healthy humans. In this paradigm, the ulnar nerve was electrically stimulated in proportion to the activation of the flexor carpi ulnaris (FCU), which is ulnar-innervated and monosynaptically innervated from Ia afferents of the FCU, defined as the "homonymous muscle," or the palmaris longus (PL), which is not innervated by the ulnar nerve and produces similar movement to the FCU, defined as the "synergist muscle." The ARC boosted the activity of the homonymous muscle and wrist joint movement during a visually guided reaching task. Participants could control muscle activity to utilize the ARC for the volitional control of wrist joint movement and then readapt to the absence of the ARC to either input muscle. Participants reduced homonymous muscle recruitment with practice, regardless of the input muscle. However, the adaptation process in the synergist muscle was dependent on the input muscle. The activity of the synergist muscle decreased when the input was the homonymous muscle, whereas it increased when it was the synergist muscle. This reorganization of the neuromotor map, which was maintained as an aftereffect of the ARC, was observed only when the input was the synergist muscle. These findings demonstrate that the ARC induced reorganization of neuromotor map in a targeted and sustainable manner.

  9. The development of an experimental model of contaminated muscle injury in rabbits.

    Science.gov (United States)

    Eardley, Will G P; Martin, Kevin R; Taylor, Chris; Kirkman, Emrys; Clasper, Jon C; Watts, Sarah A

    2012-12-01

    Extent of tissue trauma and contamination determine outcome in extremity injury. In contrast to fracture, osteomyelitis, and closed muscle injury studies, there are limited small animal models of extremity muscle trauma and contamination. To address this we developed a model of contaminated muscle injury in rabbits. Twenty-eight anesthetized New Zealand White rabbits underwent open controlled injury of the flexor carpi ulnaris (FCU). Twenty-two animals had subsequent contamination of the injured muscle with Staphylococcus aureus. All animals were sacrificed at 48 hours and the level of muscle injury and contamination determined by quantitative histological and microbiological analysis. A 1-kg mass dropped 300 mm onto the mobilized FCU resulted in localized necrosis of the muscle belly. Delivery of a mean challenge of 3.71 × 10(6) cfu/100 µL S aureus by droplet spread onto the injured muscle produced a muscle contamination of 8.79 × 10(6) cfu/g at 48 hours. Ipsilateral axillary lymph nodes demonstrated clinically significant activation. All animals had normal body temperature and hematological parameters throughout and blood and urinalysis culture at autopsy were negative for organisms. This model allows reproducible muscle injury and contamination with the organism ubiquitous to extremity wound infection at a level sufficient to allow quantitative assessment of subsequent wound care interventions without incurring systemic involvement.

  10. Distribution of different fibre types of M. extensor carpi radialis longus of the rat.

    Science.gov (United States)

    Rodrigues, A de C; Silva M dal, D; Pai, V D

    1994-12-01

    As revealed by the NADH-diaphorase and myosine ATPase, the M. extensor carpi radialis longus of the rat possesses at least 3 main kinds of fibres, with different distribution on the superficial and deep portions of the muscle. The superficial portion revealed that 67.68% are FG (fast-twitch-glycolytic) fibres, 14.72% are FOG (fast-twitch-oxidative) fibres and 17.60% are SO (slow-twitch-glycolytic) fibres. Already the deep portion revealed that 71.29% are SO (slow-twitch-glycolytic) fibres, 17.46% are FOG (fast-twitch-oxidative-glycolytic) fibres and 11.25% are FG (fast-twitch-glycolytic) fibres. The miosine ATPase reaction was used to demonstrate contracting characteristics. These findings suggest that the movements of fast contraction of the M. extensor carpi radialis longus are predominant.

  11. The influence of wrist posture on the time and frequency EMG signal measures of forearm muscles.

    Science.gov (United States)

    Roman-Liu, Danuta; Bartuzi, Paweł

    2013-03-01

    This study investigates how altering wrist posture influences the relationship between the time and frequency measures of the electromyography (EMG) signal of extensor digitorum communis (EDC) and flexor carpi ulnaris (FCU). Thirteen participants exerted handgrip force related to maximum voluntary contraction (MVC) in four tests: 20%MVC and 50%MVC in neutral wrist posture and 20%MVC in full wrist flexion and extension. EMG measurements from EDC and FCU were used to calculate normalized values of amplitude (nRMS) and mean and median frequency of the power spectrum (nMPF, nMF). During muscle shortening (wrist flexion for FCU and wrist extension for EDC) nRMS was approximately twofold higher than in neutral posture for FCU and fourfold for EDC. All measures obtained at 20%MVC in neutral posture were significantly different from 20%MVC in wrist flexion for FCU and 20%MVC in wrist extension for EDC (pMVC and 20%MVC at neutral posture (nRMS) were significant for both muscles, although in nMPF and nMF for EDC only. Muscle shortening changed the pattern of statistical significance when the time and frequency domain measures were compared, whereas muscle lengthening did not. It can be concluded that muscle shortening caused by altering wrist posture influences the relationship between the time and frequency measures in both muscles. This suggests that in studies using EMG in different wrist postures, changes in the relationship between the time and the frequency measures should be considered.

  12. The pattern of muscle involvement in ulnar neuropathy at the elbow

    Directory of Open Access Journals (Sweden)

    Dariush Eliaspour

    2012-01-01

    Full Text Available Objective: To determine the pattern of muscle involvement in patients with ulnar neuropathy at the elbow. Materials and Methods: This study evaluated all patients referred for upper limb electrodiagnostic study (EDX during 2007-2011 and included. patients with clinical signs and symptoms of ulnar neuropathy at the elbow. All patients had nerve conduction studies (NCS for ulnar neuropathy. Needle electromyography (EMG of four ulnar innervated muscles, flexor carpi ulnaris (FCU, flexor digitrom profoundus (FDP, first dorsal interosseous (FDI and abductor digiti minimi (ADM was evaluated. Results: During the study period 34 (23 males and 11 females patients were diagnosed with ulnar neuropathy at the elbow and three of them had bilateral involvement. Muscle involvement by EMG was as follows: FDI: 91.9%, ADM: 91.3%, FCU: 64.9% and FDP: 56.8%. Conclusion: In this study, EMG abnormalities of nerve damage were presented more commonly in the FCU muscle than in the FDP in patients with ulnar nerve lesion at the elbow.

  13. Predilection Muscles and Physical Condition of Raccoon Dogs (Nyctereutes procyonoides Experimentally Infected with Trichinella spiralis and Trichinella nativa

    Directory of Open Access Journals (Sweden)

    Helin H

    2001-12-01

    Full Text Available The predilection muscles of Trichinella spiralis and T. nativa were studied in 2 experimental groups of 6 raccoon dogs (Nyctereutes procyonoides, the third group serving as a control for clinical signs. The infection dose for both parasites was 1 larva/g body weight. After 12 weeks, the animals were euthanized and 13 sampling sites were analysed by the digestion method. Larvae were found in all sampled skeleton muscles of the infected animals, but not in the specimens from the heart or intestinal musculature. Both parasite species reproduced equally well in the raccoon dog. The median density of infection in positive tissues was 353 larvae per gram (lpg with T. spiralis and 343 lpg with T. nativa. All the infected animals had the highest larvae numbers in the carpal flexors (M. flexor carpi ulnaris. Also tongue and eye muscles had high infection levels. There were no significant differences in the predilection sites between these 2 parasite species. Trichinellosis increased the relative amount of fat, but not the body weight in the captive raccoon dogs. Thus, Trichinella as a muscle parasite might have catabolic effect on these animals.

  14. sEMG Feature Analysis on Forearm Muscle Fatigue During Isometric Contractions

    Institute of Scientific and Technical Information of China (English)

    明东; 王欣; 徐瑞; 邱爽; 赵欣; 綦宏志; 周鹏; 张力新; 万柏坤

    2014-01-01

    In order to detect and assess the muscle fatigue state with the surface electromyography (sEMG) character-istic parameters, this paper carried out a series of isometric contraction experiments to induce the fatigue on the fore-arm muscles from four subjects, and recorded the sEMG signals of the flexor carpi ulnaris. sEMG's median frequency (MDF) and mean frequency (MF) were extracted by short term Fourier transform (STFT), and the root mean square (RMS) of wavelet coefficients in the frequency band of 5-45 Hz was obtained by continuous wavelet transform (CWT). The results demonstrate that both MDF and MF show downward trends within 1 min;however, RMS shows an upward trend within the same time. The three parameters are closely correlated with absolute values of mean corre-lation coefficients greater than 0.8. It is suggested that the three parameters above can be used as reliable indicators to evaluate the level of muscle fatigue during isometric contractions.

  15. The Body Action Coding System II: Muscle activations during the perception and expression of emotion

    Directory of Open Access Journals (Sweden)

    Elisabeth M.J. Huis in 't Veld

    2014-09-01

    Full Text Available Research into the expression and perception of emotions has mostly focused on facial expressions. Recently, body postures have become increasingly important in research, but knowledge on muscle activity during the perception or expression of emotion is lacking. The current study continues the development of a Body Action Coding System (BACS, which was initiated in a previous study, and described the involvement of muscles in the neck, shoulders and arms during expression of fear and anger. The current study expands the BACS by assessing the activity patterns of three additional muscles. Surface electromyography of muscles in the neck (upper trapezius descendens, forearms (extensor carpi ulnaris, lower back (erector spinae longissimus and calves (peroneus longus were measured during active expression and passive viewing of fearful and angry body expressions. The muscles in the forearm were strongly active for anger expression and to a lesser extent for fear expression. In contrast, muscles in the calves were recruited slightly more for fearful expressions. It was also found that muscles automatically responded to the perception of emotion, without any overt movement. The observer’s forearms responded to the perception of fear, while the muscles used for leaning backwards were activated when faced with an angry adversary. Lastly, the calf responded immediately when a fearful person was seen, but responded slower to anger. There is increasing interest in developing systems that are able to create or recognize emotional body language for the development of avatars, robots, and online environments. To that end, multiple coding systems have been developed that can either interpret or create bodily expressions based on static postures, motion capture data or videos. However, the BACS is the first coding system based on muscle activity.

  16. The Body Action Coding System II: muscle activations during the perception and expression of emotion.

    Science.gov (United States)

    Huis In 't Veld, Elisabeth M J; van Boxtel, Geert J M; de Gelder, Beatrice

    2014-01-01

    Research into the expression and perception of emotions has mostly focused on facial expressions. Recently, body postures have become increasingly important in research, but knowledge on muscle activity during the perception or expression of emotion is lacking. The current study continues the development of a Body Action Coding System (BACS), which was initiated in a previous study, and described the involvement of muscles in the neck, shoulders and arms during expression of fear and anger. The current study expands the BACS by assessing the activity patterns of three additional muscles. Surface electromyography of muscles in the neck (upper trapezius descendens), forearms (extensor carpi ulnaris), lower back (erector spinae longissimus) and calves (peroneus longus) were measured during active expression and passive viewing of fearful and angry body expressions. The muscles in the forearm were strongly active for anger expression and to a lesser extent for fear expression. In contrast, muscles in the calves were recruited slightly more for fearful expressions. It was also found that muscles automatically responded to the perception of emotion, without any overt movement. The observer's forearms responded to the perception of fear, while the muscles used for leaning backwards were activated when faced with an angry adversary. Lastly, the calf responded immediately when a fearful person was seen, but responded slower to anger. There is increasing interest in developing systems that are able to create or recognize emotional body language for the development of avatars, robots, and online environments. To that end, multiple coding systems have been developed that can either interpret or create bodily expressions based on static postures, motion capture data or videos. However, the BACS is the first coding system based on muscle activity.

  17. A simple blind tenolysis for flexor carpi radialis tendinopathy

    NARCIS (Netherlands)

    Brink, Peter R G; Franssen, Bas B G M; Disseldorp, Dominique J G

    2015-01-01

    BACKGROUND: Flexor carpi radialis (FCR) tendinopathy is an entity with a chronic form (repetitiveness of work) and an acute form (acute overstretching of the wrist). Confirmation of this syndrome can be established by injection of a small amount of a local anesthetic in the sheet of the FCR at this

  18. Intramuscular Connective Tissue Differences in Spastic and Control Muscle: A Mechanical and Histological Study

    Science.gov (United States)

    de Bruin, Marije; Smeulders, Mark J.; Kreulen, Michiel; Huijing, Peter A.; Jaspers, Richard T

    2014-01-01

    Cerebral palsy (CP) of the spastic type is a neurological disorder characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks. Secondary to the spasticity, muscle adaptation is presumed to contribute to limitations in the passive range of joint motion. However, the mechanisms underlying these limitations are unknown. Using biopsies, we compared mechanical as well as histological properties of flexor carpi ulnaris muscle (FCU) from CP patients (n = 29) and healthy controls (n = 10). The sarcomere slack length (mean 2.5 µm, SEM 0.05) and slope of the normalized sarcomere length-tension characteristics of spastic fascicle segments and single myofibre segments were not different from those of control muscle. Fibre type distribution also showed no significant differences. Fibre size was significantly smaller (1933 µm2, SEM 190) in spastic muscle than in controls (2572 µm2, SEM 322). However, our statistical analyses indicate that the latter difference is likely to be explained by age, rather than by the affliction. Quantities of endomysial and perimysial networks within biopsies of control and spastic muscle were unchanged with one exception: a significant thickening of the tertiary perimysium (3-fold), i.e. the connective tissue reinforcement of neurovascular tissues penetrating the muscle. Note that this thickening in tertiary perimysium was shown in the majority of CP patients, however a small number of patients (n = 4 out of 23) did not have this feature. These results are taken as indications that enhanced myofascial loads on FCU is one among several factors contributing in a major way to the aetiology of limitation of movement at the wrist in CP and the characteristic wrist position of such patients. PMID:24977410

  19. Intramuscular connective tissue differences in spastic and control muscle: a mechanical and histological study.

    Directory of Open Access Journals (Sweden)

    Marije de Bruin

    Full Text Available Cerebral palsy (CP of the spastic type is a neurological disorder characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks. Secondary to the spasticity, muscle adaptation is presumed to contribute to limitations in the passive range of joint motion. However, the mechanisms underlying these limitations are unknown. Using biopsies, we compared mechanical as well as histological properties of flexor carpi ulnaris muscle (FCU from CP patients (n = 29 and healthy controls (n = 10. The sarcomere slack length (mean 2.5 µm, SEM 0.05 and slope of the normalized sarcomere length-tension characteristics of spastic fascicle segments and single myofibre segments were not different from those of control muscle. Fibre type distribution also showed no significant differences. Fibre size was significantly smaller (1933 µm2, SEM 190 in spastic muscle than in controls (2572 µm2, SEM 322. However, our statistical analyses indicate that the latter difference is likely to be explained by age, rather than by the affliction. Quantities of endomysial and perimysial networks within biopsies of control and spastic muscle were unchanged with one exception: a significant thickening of the tertiary perimysium (3-fold, i.e. the connective tissue reinforcement of neurovascular tissues penetrating the muscle. Note that this thickening in tertiary perimysium was shown in the majority of CP patients, however a small number of patients (n = 4 out of 23 did not have this feature. These results are taken as indications that enhanced myofascial loads on FCU is one among several factors contributing in a major way to the aetiology of limitation of movement at the wrist in CP and the characteristic wrist position of such patients.

  20. Intramuscular connective tissue differences in spastic and control muscle: a mechanical and histological study.

    Science.gov (United States)

    de Bruin, Marije; Smeulders, Mark J; Kreulen, Michiel; Huijing, Peter A; Jaspers, Richard T

    2014-01-01

    Cerebral palsy (CP) of the spastic type is a neurological disorder characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks. Secondary to the spasticity, muscle adaptation is presumed to contribute to limitations in the passive range of joint motion. However, the mechanisms underlying these limitations are unknown. Using biopsies, we compared mechanical as well as histological properties of flexor carpi ulnaris muscle (FCU) from CP patients (n = 29) and healthy controls (n = 10). The sarcomere slack length (mean 2.5 µm, SEM 0.05) and slope of the normalized sarcomere length-tension characteristics of spastic fascicle segments and single myofibre segments were not different from those of control muscle. Fibre type distribution also showed no significant differences. Fibre size was significantly smaller (1933 µm2, SEM 190) in spastic muscle than in controls (2572 µm2, SEM 322). However, our statistical analyses indicate that the latter difference is likely to be explained by age, rather than by the affliction. Quantities of endomysial and perimysial networks within biopsies of control and spastic muscle were unchanged with one exception: a significant thickening of the tertiary perimysium (3-fold), i.e. the connective tissue reinforcement of neurovascular tissues penetrating the muscle. Note that this thickening in tertiary perimysium was shown in the majority of CP patients, however a small number of patients (n = 4 out of 23) did not have this feature. These results are taken as indications that enhanced myofascial loads on FCU is one among several factors contributing in a major way to the aetiology of limitation of movement at the wrist in CP and the characteristic wrist position of such patients.

  1. Differences in Muscle Activity During Cable Resistance Training Are Influenced by Variations in Handle Types.

    Science.gov (United States)

    Rendos, Nicole K; Heredia Vargas, Héctor M; Alipio, Taislaine C; Regis, Rebeca C; Romero, Matthew A; Signorile, Joseph F

    2016-07-01

    Rendos, NK, Heredia Vargas, HM, Alipio, TC, Regis, RC, Romero, MA, and Signorile, JF. Differences in muscle activity during cable resistance training are influenced by variations in handle types. J Strength Cond Res 30(7): 2001-2009, 2016-There has been a recent resurgence in the use of cable machines for resistance training allowing movements that more effectively simulate daily activities and sports-specific movements. By necessity, these devices require a machine/human interface through some type of handle. Considerable data from material handling, industrial engineering, and exercise training studies indicate that handle qualities, especially size and shape, can significantly influence force production and muscular activity, particularly of the forearm muscles, which affect the critical link in activities that require object manipulation. The purpose for this study was to examine the influence of three different handle conditions: standard handle (StandH), ball handle with the cable between the index and middle fingers (BallIM), and ball handle with the cable between the middle and ring fingers (BallMR), on activity levels (rmsEMG) of the triceps brachii lateral and long heads (TriHLat, TriHLong), brachioradialis (BR), flexor carpi radialis (FCR), extensor carpi ulnaris, and extensor digitorum (ED) during eight repetitions of standing triceps pushdown performed from 90° to 0° elbow flexion at 1.5 s per contractile stage. Handle order was randomized. No significant differences were seen for triceps or BR rmsEMG across handle conditions; however, relative patterns of activation did vary for the forearm muscles by handle condition, with more coordinated activation levels for the FCR and ED during the ball handle conditions. In addition, the rmsEMG for the ED was significantly higher during the BallIM than any other condition and during the BallMR than the StandH. These results indicate that the use of ball handles with the cable passing between different fingers

  2. Modulation of forelimb and hindlimb muscle activity during quadrupedal tied-belt and split-belt locomotion in intact cats.

    Science.gov (United States)

    Frigon, A; Thibaudier, Y; Hurteau, M-F

    2015-04-02

    The modulation of the neural output to forelimb and hindlimb muscles when the left and right sides step at different speeds from one another in quadrupeds was assessed by obtaining electromyography (EMG) in seven intact adult cats during split-belt locomotion. To determine if changes in EMG during split-belt locomotion were modulated according to the speed of the belt the limb was stepping on, values were compared to those obtained during tied-belt locomotion (equal left-right speeds) at matched speeds. Cats were chronically implanted for EMG, which was obtained from six muscles: biceps brachii, triceps brachii, flexor carpi ulnaris, sartorius, vastus lateralis and medial gastrocnemius. During tied-belt locomotion, cats stepped from 0.4 to 1.0m/s in 0.1m/s increments whereas during split-belt locomotion, cats stepped with left-right speed differences of 0.1 to 0.4m/s in 0.1m/s increments. During tied-belt locomotion, EMG burst durations and mean EMG amplitudes of all muscles respectively decreased and increased with increasing speed. During split-belt locomotion, there was a clear differential modulation of the EMG patterns between flexors and extensors and between the slow and fast sides. Changes in the EMG pattern of some muscles could be explained by the speed of the belt the limb was stepping on, while in other muscles there were clear dissociations from tied-belt values at matched speeds. Therefore, results show that EMG patterns during split-belt locomotion are modulated to meet task requirements partly via signals related to the stepping speed of the homonymous limb and from the other limbs.

  3. Enthesopathy of the Extensor Carpi Radialis Brevis Origin: Effective Communication Strategies.

    Science.gov (United States)

    Drake, Matthew L; Ring, David C

    2016-06-01

    Enthesopathy of the extensor carpi radialis brevis origin, generally known as tennis elbow, is a common condition arising in middle-aged persons. The diagnosis is typically clear based on the patient interview and physical examination alone; therefore, imaging and other diagnostic tests are usually unnecessary. The natural history of the disorder is spontaneous resolution, but it can last for >1 year. The patient's attitude and circumstances, including stress, distress, and ineffective coping strategies, determine the intensity of the pain and the magnitude of the disability. Despite the best efforts of medical science, no treatments, invasive or noninvasive, have been proven to alter the natural history of the condition. Given the lack of disease-modifying treatments for enthesopathy of the extensor carpi radialis brevis origin, orthopaedic surgeons can benefit from learning effective communication strategies to help convey accurate information that is hopeful and enabling.

  4. I quarant'anni del Museo Monumento al deportato di Carpi

    Directory of Open Access Journals (Sweden)

    Elena Pirazzoli

    2014-03-01

    Full Text Available L'8 dicembre 2013, il Museo Monumento al deportato politico e razziale di Carpi ha festeggiato il quarantennale dall'inaugurazione, riaprendo al pubblico dopo un intervento di manutenzione profonda. Un museo che oggi, a quarant'anni dalla sua inaugurazione e addirittura a cinquanta dalla sua ideazione, ha uno straordinario valore di documento, testimoniando una precocissima fase di «museografia della memoria».

  5. Anatomical study on The Arm Greater Yang Small Intestine Meridian Muscle in Human

    Directory of Open Access Journals (Sweden)

    Kyoung-Sik, Park

    2004-06-01

    Full Text Available This study was carried to identify the component of Small Intestine Meridian Muscle in human, dividing the regional muscle group into outer, middle, and inner layer. the inner part of body surface were opened widely to demonstrate muscles, nerve, blood vessels and the others, displaying the inner structure of Small Intestine Meridian Muscle. We obtained the results as follows; 1. Small Intestine Meridian Muscle is composed of the muscle, nerve and blood vessels. 2. In human anatomy, it is present the difference between a term of nerve or blood vessels which control the muscle of Meridian Muscle and those which pass near by Meridian Muscle. 3. The inner composition of meridian muscle in human arm is as follows ; 1 Muscle ; Abd. digiti minimi muscle(SI-2, 3, 4, pisometacarpal lig.(SI-4, ext. retinaculum. ext. carpi ulnaris m. tendon.(SI-5, 6, ulnar collateral lig.(SI-5, ext. digiti minimi m. tendon(SI-6, ext. carpi ulnaris(SI-7, triceps brachii(SI-9, teres major(SI-9, deltoid(SI-10, infraspinatus(SI-10, 11, trapezius(Sl-12, 13, 14, 15, supraspinatus(SI-12, 13, lesser rhomboid(SI-14, erector spinae(SI-14, 15, levator scapular(SI-15, sternocleidomastoid(SI-16, 17, splenius capitis(SI-16, semispinalis capitis(SI-16, digasuicus(SI-17, zygomaticus major(Il-18, masseter(SI-18, auriculoris anterior(SI-19 2 Nerve ; Dorsal branch of ulnar nerve(SI-1, 2, 3, 4, 5, 6, br. of mod. antebrachial cutaneous n.(SI-6, 7, br. of post. antebrachial cutaneous n.(SI-6,7, br. of radial n.(SI-7, ulnar n.(SI-8, br. of axillary n.(SI-9, radial n.(SI-9, subscapular n. br.(SI-9, cutaneous n. br. from C7, 8(SI-10, 14, suprascapular n.(SI-10, 11, 12, 13, intercostal n. br. from T2(SI-11, lat. supraclavicular n. br.(SI-12, intercostal n. br. from C8, T1(SI-12, accessory n. br.(SI-12, 13, 14, 15, 16, 17, intercostal n. br. from T1,2(SI-13, dorsal scapular n.(SI-14, 15, cutaneous n. br. from C6, C7(SI-15, transverse cervical n.(SI-16, lesser occipital n. & great auricular n. from

  6. Neuromuscular partitioning in the extensor carpi radialis longus and brevis based on intramuscular nerve distribution patterns: A three-dimensional modeling study.

    Science.gov (United States)

    Ravichandiran, Mayoorendra; Ravichandiran, Nisanthini; Ravichandiran, Kajeandra; McKee, Nancy H; Richardson, Denyse; Oliver, Michele; Agur, Anne M

    2012-04-01

    Differential activation of specific regions within a skeletal muscle has been linked to the presence of neuromuscular compartments. However, few studies have investigated the extra- or intramuscular innervation throughout the muscle volume of extensor carpi radialis longus (ECRL) and brevis (ECRB). The aim of this study was to determine the presence of neuromuscular partitions in ECRL and ECRB based on the extra- and intramuscular innervation using three-dimensional modeling. The extra- and intramuscular nerve distribution was digitized and reconstructed in 3D in all the muscle volumes using Autodesk Maya in seven formalin embalmed cadaveric specimens (mean age, 75.7 ± 15.2 years). The intramuscular nerve distribution was modeled in all the muscle volumes. ECRL was found to have two neuromuscular compartments, superficial and deep. One branch from the radial nerve proper was found to innervate ECRL. This branch was divided into anterior and posterior branches to the superficial and deep compartments, respectively. Five innervation patterns were identified in ECRB with partitioning of the muscle belly into two, three, or four compartments, in a proximal to distal direction depending on the number of nerve branches entering the muscle belly. The ECRL and ECRB both demonstrated neuromuscular compartmentalization based on intramuscular innervation. According to the partitioning hypothesis, a muscle may be differentially activated depending on the required function of the muscle, thus allowing multifunctional muscles to contribute to a variety of movements. Therefore, the increased number of neuromuscular partitions in ECRB when compared with ECRL could be due to the need for more differential recruitment in the ECRB depending on force requirements.

  7. Fatigue effects on tracking performance and muscle activity

    NARCIS (Netherlands)

    Huysmans, M.A.; Hoozemans, M.J.M.; Beek, A.J. van der; Looze, M.P. de; Dieën, J.H. van

    2008-01-01

    It has been suggested that fatigue affects proprioception and consequently movement accuracy, the effects of which may be counteracted by increased muscle activity. To determine the effects of fatigue on tracking performance and muscle activity in the M. extensor carpi radialis (ECR), 11 female part

  8. High incidence and treatment of flexor carpi radialis tendinitis after trapeziectomy and abductor pollicis longus suspensionplasty for basal joint arthritis.

    Science.gov (United States)

    Low, T H; Hales, P F

    2014-10-01

    We reviewed the incidence and treatment of flexor carpi radialis tendinitis in 77 patients (81 thumbs) who had trapeziectomy and abductor pollicis longus suspensionplasty for thumb carpometacarpal joint arthritis. Eighteen patients, 20 wrists (25%) had flexor carpi radialis tendinitis. The onset was 2-10 months (mean 4.7) after surgery. Two cases had preceding trauma. Eight cases (40%) responded to splinting and steroid injection. Ten patients, 12 wrists (60%) underwent surgery after failing non-operative treatment. Eleven wrists had frayed or partially torn flexor carpi radialis tendon and one had a complete tendon rupture with pseudotendon formation. Flexor carpi radialis tenotomy and pseudotendon excision were performed. All operated patients obtained good pain relief initially post-operatively. However, the pain recurred in two patients after 8 months. One required a local steroid injection for localized tenderness at the site of the proximal tendon stump. The other patient required a revision operation for scaphotrapezoid impingement. Both obtained complete pain relief. Our study has shown a high incidence of flexor carpi radialis tendinitis following trapeziectomy and abductor pollicis longus suspensionplasty. Patients should be warned about this potential complication.

  9. Evaluation of pulsatile and nonpulsatile flow in capillaries of goat skeletal muscle using intravital microscopy.

    Science.gov (United States)

    Lee, J J; Tyml, K; Menkis, A H; Novick, R J; Mckenzie, F N

    1994-11-01

    It is commonly believed that pulsatile flow generated by the pumping action of the heart is dampened out by the time it reaches the microcirculation. In clinical practice, most of the cardiopulmonary bypass pumps and ventricular assist devices are nonpulsatile. To test the hypothesis that pulsatile flow generated by the heart does exist at the microvascular level, intravital microscopy of a large animal model (goat) was developed to visualize and to videorecord the surface microcirculation of the flexor carpi ulnaris muscle from the right forelimb. Density of perfused capillaries and red blood cell velocity in capillaries were measured in five goats during pulsatile perfusion provided by the heart and during a subsequent 3-hr period of nonpulsatile perfusion provided by a centrifugal ventricular assist device (Centrimed, Sarns 3M) that bypassed the heart. Throughout the experiment, the heart rate, innominate artery mean blood pressure, and flow remained unchanged. During the pulsatile regimen, velocities showed regular fluctuations that coincided with the period of the cardiac cycle (range of periods: 0.5-0.8 sec). The peak velocity amplitudes (range: 0.25-0.55 mm/sec) correlated directly with the amplitude of the pulse pressure. During the nonpulsatile regimen, no such correlations were seen. During pulsatile flow and during the 3-hr nonpulsatile period, capillary density remained stable at 24 capillaries/mm of test line but there were significant increases in red cell velocity, from 0.8 to 1.2 mm/sec (P < 0.05), and in coefficient of variation of velocity (used as an index of flow heterogeneity), from 19 to 34% (P < 0.05). We conclude that (1) pulsatility exists in the capillary bed and that it directly correlates with the pumping action of the heart and (2) nonpulsatile flow produced by the ventricular assist device does not cause an acute deterioration in microvascular perfusion. We interpret the increase in heterogeneity of flow as an early sign of

  10. Avulsion fracture of the extensor carpi radialis longus carpal insertion due to a basketball injury: case report and literature review.

    Science.gov (United States)

    Robert, N; Zbili, D; Bellity, J; Doursounian, L; Mauprivez, R

    2014-12-01

    Articular fractures of the base of the 2nd metacarpal involving the extensor carpi radialis longus insertion are unusual and poorly understood. There is no consensus as to how these fractures should be treated. We report the case of a 2nd metacarpal base fracture in a professional basketball player that was treated surgically with open reduction and internal fixation using cannulated screws. The management of this case is compared to similar cases in the literature.

  11. Treatise on skull fractures by Berengario da Carpi (1460-1530).

    Science.gov (United States)

    Mazzola, Riccardo F; Mazzola, Isabella C

    2009-11-01

    Jacopo Berengario was born in Carpi, a medieval city close to Modena (northern Italy), circa 1460. He studied medicine at Bologna University and, in 1489, graduated in philosophy and medicine. He was appointed lecturer in anatomy and surgery at the same university, a position that he maintained for 24 years. Between 1514 and 1523, Berengario published some important anatomic and surgical works, which gave considerable fame to him.Commentaria... supra Anatomiam Mundini (Commentary... on the Anatomy of Mondino), published in 1521, constitutes the first example of an illustrated anatomic textbook ever printed. The anatomic illustrations were intended for explaining the text. Artistically speaking, the plates are typical examples of the Renaissance period and worthy of the greatest consideration.De Fractura Calvae sive Cranei (On Fracture of the Calvaria or Cranium), published in Bologna in 1518, is the first treatise devoted to head injuries ever printed. It is a landmark in the development of cranial surgery that went through numerous editions. The text was prepared in 2 months and dedicated to Lorenzo de' Medici, Duke of Urbino, who experienced a skull injury in the occipital region. Berengario wanted to demonstrate to other physicians his knowledge of anatomy and his expertise on the brain and head traumas. The book includes the illustration of an entire surgical kit or a corpus instrumentorum for performing cranial operations, which appeared for the first time in a printed book. However, Berengario's highly commendable aim was to indicate to the reader the step-by-step procedure of craniotomy for management of skull fractures along with the sequential use of the previously presented instruments.

  12. Late ulnar paralysis. Study of seventeen cases.

    Science.gov (United States)

    Mansat, M; Bonnevialle, P; Fine, X; Guiraud, B; Testut, M F

    1983-01-01

    Seventeen cases of late ulnar paralysis treated by neurolysis-transposition are reported. The clinical characteristics of these paralysis are emphasized. A very prolonged symptom free interval, a rapid onset and a severe involvement. The ulnar transposition was most often done subcutaneously. Cubitus valgus and definite nerve compression proximal to the arcade of the flexor carpi ulnaris muscle are almost always present. The results as regards the neuropathy are notable: no patient is completely cured and only half are improved. An anatomical study of the nerve path shows the essential role, in the compression of the nerve, of the muscular arcade of the flexor carpi ulnaris muscle which acts in a way similar to the bridge of a violin. Hence, opening it longitudinally is the principal procedure of the neurolysis. This should be routine before the first signs of neuropathy occur in an elbow whose axis is out of alignment as a sequela of a childhood injury.

  13. [Late ulnar paralysis. Study of a series of 17 cases].

    Science.gov (United States)

    Mansat, M; Bonnevialle, P; Fine, X; Guiraud, B; Testut, M F

    1984-02-16

    Seventeen cases of late ulnar paralysis treated by neurolysis-transposition are reported. The clinical characteristics of these paralyses are emphasized: very prolonged symptom free interval, rapid onset and severe involvement. Ulnar transposition was most often done subcutaneously. Cubitus valgus and definite nerve compression proximal to the arcade of the flexor carpi ulnaris muscle are almost always present. The results as regards the neuropathy are undependable: no patient is completely cured and only half are improved. An anatomical study of the nerve path shows the essential role, in the compression of the nerve, of the muscular arcade of the flexor carpi ulnaris muscle which acts in a way similar to the bridge of a violin. Hence, opening it longitudinally is the principal step of neurolysis. This should be routine before the first signs of neuropathy occur in an elbow whose axis is out of alignment as a sequela of a childhood injury.

  14. Ischemia causes muscle fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D. M.

    2001-01-01

    The purpose of this investigation was to determine whether ischemia, which reduces oxygenation in the extensor carpi radialis (ECR) muscle, causes a reduction in muscle force production. In eight subjects, muscle oxygenation (TO2) of the right ECR was measured noninvasively and continuously using near infrared spectroscopy (NIRS) while muscle twitch force was elicited by transcutaneous electrical stimulation (1 Hz, 0.1 ms). Baseline measurements of blood volume, muscle oxygenation and twitch force were recorded continuously, then a tourniquet on the upper arm was inflated to one of five different pressure levels: 20, 40, 60 mm Hg (randomized order) and diastolic (69 +/- 9.8 mm Hg) and systolic (106 +/- 12.8 mm Hg) blood pressures. Each pressure level was maintained for 3-5 min, and was followed by a recovery period sufficient to allow measurements to return to baseline. For each respective tourniquet pressure level, mean TO2 decreased from resting baseline (100% TO2) to 99 +/- 1.2% (SEM), 96 +/- 1.9%, 93 +/- 2.8%, 90 +/- 2.5%, and 86 +/- 2.7%, and mean twitch force decreased from resting baseline (100% force) to 99 +/- 0.7% (SEM), 96 +/- 2.7%, 93 +/- 3.1%, 88 +/- 3.2%, and 86 +/- 2.6%. Muscle oxygenation and twitch force at 60 mm Hg tourniquet compression and above were significantly lower (P < 0.05) than baseline value. Reduced twitch force was correlated in a dose-dependent manner with reduced muscle oxygenation (r = 0.78, P < 0.001). Although the correlation does not prove causation, the results indicate that ischemia leading to a 7% or greater reduction in muscle oxygenation causes decreased muscle force production in the forearm extensor muscle. Thus, ischemia associated with a modest decline in TO2 causes muscle fatigue.

  15. Ischemia causes muscle fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D. M.

    2001-01-01

    The purpose of this investigation was to determine whether ischemia, which reduces oxygenation in the extensor carpi radialis (ECR) muscle, causes a reduction in muscle force production. In eight subjects, muscle oxygenation (TO2) of the right ECR was measured noninvasively and continuously using near infrared spectroscopy (NIRS) while muscle twitch force was elicited by transcutaneous electrical stimulation (1 Hz, 0.1 ms). Baseline measurements of blood volume, muscle oxygenation and twitch force were recorded continuously, then a tourniquet on the upper arm was inflated to one of five different pressure levels: 20, 40, 60 mm Hg (randomized order) and diastolic (69 +/- 9.8 mm Hg) and systolic (106 +/- 12.8 mm Hg) blood pressures. Each pressure level was maintained for 3-5 min, and was followed by a recovery period sufficient to allow measurements to return to baseline. For each respective tourniquet pressure level, mean TO2 decreased from resting baseline (100% TO2) to 99 +/- 1.2% (SEM), 96 +/- 1.9%, 93 +/- 2.8%, 90 +/- 2.5%, and 86 +/- 2.7%, and mean twitch force decreased from resting baseline (100% force) to 99 +/- 0.7% (SEM), 96 +/- 2.7%, 93 +/- 3.1%, 88 +/- 3.2%, and 86 +/- 2.6%. Muscle oxygenation and twitch force at 60 mm Hg tourniquet compression and above were significantly lower (P ischemia leading to a 7% or greater reduction in muscle oxygenation causes decreased muscle force production in the forearm extensor muscle. Thus, ischemia associated with a modest decline in TO2 causes muscle fatigue.

  16. Warner-Bratzler shear evaluations of 40 bovine muscles.

    Science.gov (United States)

    Belew, J B; Brooks, J C; McKenna, D R; Savell, J W

    2003-08-01

    Forty muscles from each of 20 beef carcass sides were used to perform Warner-Bratzler shear (WBS) force determinations for within and among muscle effects. The M. triceps brachii differed (P psoas major, and M. semimembranosus all had significant location effects. Muscles were allocated into "very tender," "tender," "intermediate" or "tough" categories. Those muscles considered "very tender" (WBS iliacus, M. psoas major, M. serratus ventralis, M. biceps brachii, M. obliquus internus abdominis, and M. vastus medius. Muscles considered "tender" (3.2 kg 4.6 kg) were the M. extensor carpi radialis, M. trapezius, M. brachialis, M. pectoralis profundus, and M. flexor digitorum superficialis (hind limb). The diaphragm muscle was the most tender (WBS=2.03 kg), and the M. flexor digitorum superficialis was the toughest (WBS=7.74 kg). Tenderness, as measured by WBS, varied among and within bovine muscles, and knowledge of this variation allows for more appropriate use for specific purposes in the marketplace.

  17. Nuevos puñales de remaches de bronce procedentes de La Mesa de Carpió (Villagonzalo de Tormes, Salamanca

    Directory of Open Access Journals (Sweden)

    Pedro Javier CRUZ SÁNCHEZ

    2009-12-01

    Full Text Available RESUMEN: La aparición en las siembras de La Mesa de Carpió (Villagonzalo de Tormes, Salamanca de un nutrido lote de acabados metálicos encuadrados en la Edad del Bronce, entre ellos el par de cuchillos de roblones que analizamos, así como una serie de evidencias relacionadas con una actividad fundidora a pequeña escala, dan pie a plantear algunas hipótesis sobre una presunta jerarquía de poblamiento durante el Bronce Final en el valle medio del Tormes, cuyo centro capitalizador, sede de una emergente élite social, se encontraría en la propia Mesa de Carpió.ABSTRACT: The come out of a considerable amount of metalwork in La Mesa de Carpió fields belonging to Bronze Age (such as that couple of flat-rivetted bronze-daggers which are the object of our study, in addition to a serie of evidences in relationship with a small-scale bronze metalwork; it helps to set up some thoughts about an hypothetical hierarchy of settlements, during the Late Bronze Age in the Tormes middle valley. The main centre, head of an emerging social elite, would be placed in La Mesa de Carpios itself.

  18. Forearm muscle oxygenation decreases with low levels of voluntary contraction

    Science.gov (United States)

    Murthy, G.; Kahan, N. J.; Hargens, A. R.; Rempel, D. M.

    1997-01-01

    The purpose of our investigation was to determine if the near infrared spectroscopy technique was sensitive to changes in tissue oxygenation at low levels of isometric contraction in the extensor carpi radialis brevis muscle. Nine subjects were seated with the right arm abducted to 45 degrees, elbow flexed to 85 degrees, forearm pronated 45 degrees, and wrist and forearm supported on an armrest throughout the protocol. Altered tissue oxygenation was measured noninvasively with near infrared spectroscopy. The near infrared spectroscopy probe was placed over the extensor carpi radialis brevis of the subject's right forearm and secured with an elastic wrap. After 1 minute of baseline measurements taken with the muscle relaxed, four different loads were applied just proximal to the metacarpophalangeal joint such that the subjects isometrically contracted the extensor carpi radialis brevis at 5, 10, 15, and 50% of the maximum voluntary contraction for 1 minute each. A 3-minute recovery period followed each level of contraction. At the end of the protocol, with the probe still in place, a value for ischemic tissue oxygenation was obtained for each subject. This value was considered the physiological zero and hence 0% tissue oxygenation. Mean tissue oxygenation (+/-SE) decreased from resting baseline (100% tissue oxygenation) to 89 +/- 4, 81 +/- 8, 78 +/- 8, and 47 +/- 8% at 5, 10, 15, and 50% of the maximum voluntary contraction, respectively. Tissue oxygenation levels at 10, 15, and 50% of the maximum voluntary contraction were significantly lower (p muscle contraction and that near infrared spectroscopy is a sensitive technique for detecting deoxygenation noninvasively at low levels of forearm muscle contraction. Our findings have important implications in occupational medicine because oxygen depletion induced by low levels of muscle contraction may be directly linked to muscle fatigue.

  19. A variation of the palmaris profundus muscle

    Directory of Open Access Journals (Sweden)

    Stark ME

    2010-02-01

    Full Text Available During routine anatomical dissection of the anterior compartment of the forearm region, a tendinous-musculo-tendinous muscle was found on the right forearm originating from the medial aspect of the radial shaft and inserting into the palmar aponeurosis. The muscle coursed deep to pronator teres muscle, parallel and lateral to the flexor digitorum superficialis muscle and deep to the tendon of the flexor carpi radialis. Distally, the muscle tendon coursed under the flexor retinaculum and it was invested with the median nerve by a common fascial sheath. The muscle was found in the presence of an intact palmaris longus muscle. Because of its attachments and course, the muscle was classified as a palmaris profundus muscle. Several subtypes of palmaris profundus muscles have been reported. To our knowledge this is the first case of a palmaris profundus with a tendon originating from the medial aspect of the radial diaphysis, a muscular portion and a distal tendon inserting in the palmar aponeurosis. Anatomical variations of muscles in the flexor compartment of the forearm may have functional, diagnostic, and surgical implications.

  20. Muscle relaxation of the foot reduces corticospinal excitability of hand muscles and enhances intracortical inhibition

    Directory of Open Access Journals (Sweden)

    Kouki eKato

    2016-05-01

    Full Text Available The object of this study was to clarify the effects of foot muscle relaxation on activity in the primary motor cortex of the hand area. Subjects were asked to volitionally relax the right foot from sustained contraction of either the dorsiflexor (tibialis anterior; TA relaxation or plantarflexor (soleus; SOL relaxation in response to an auditory stimulus. Single- and paired-pulse transcranial magnetic stimulation (TMS was delivered to the hand area of the left primary motor cortex at different time intervals before and after the onset of TA or SOL relaxation. Motor evoked potentials (MEPs were recorded from the right extensor carpi radialis (ECR and flexor carpi radialis (FCR. MEP amplitudes of ECR and FCR caused by single-pulse TMS temporarily decreased after TA and SOL relaxation onset, respectively, as compared with those of the resting control. Furthermore, short-interval intracortical inhibition (SICI of ECR evaluated with paired-pulse TMS temporarily increased after TA relaxation onset. Our findings indicate that muscle relaxation of the dorsiflexor reduced corticospinal excitability of the ipsilateral hand muscles. This is most likely caused by an increase in intracortical inhibition.

  1. Cerebellar brain inhibition in the target and surround muscles during voluntary tonic activation.

    Science.gov (United States)

    Panyakaew, Pattamon; Cho, Hyun Joo; Srivanitchapoom, Prachaya; Popa, Traian; Wu, Tianxia; Hallett, Mark

    2016-04-01

    Motor surround inhibition is the neural mechanism that selectively favours the contraction of target muscles and inhibits nearby muscles to prevent unwanted movements. This inhibition was previously reported at the onset of a movement, but not during a tonic contraction. Cerebellar brain inhibition (CBI) is reduced in active muscles during tonic activation; however, it has not been studied in the surround muscles. CBI was evaluated in the first dorsal interosseus (FDI) muscle as the target muscle, and the abductor digiti minimi, flexor carpi radialis and extensor carpi radialis muscles as surround muscles, during rest and tonic activation of the FDI muscle in 21 subjects. Cerebellar stimulation was performed under magnetic resonance imaging-guided neuronavigation targeting lobule VIII of the cerebellar hemisphere. Stimulus intensities for cerebellar stimulation were based on the resting motor cortex threshold (RMT) and adjusted for the depth difference between the cerebellar and motor cortices. We used 90-120% of the adjusted RMT as the conditioning stimulus intensity during rest. The intensity that generated the best CBI at rest in the FDI muscle was selected for use during tonic activation. During selective tonic activation of the FDI muscle, CBI was significantly reduced only for the FDI muscle, and not for the surround muscles. Unconditioned motor evoked potential sizes were increased in all muscles during FDI muscle tonic activation as compared with rest, despite background electromyography activity increasing only for the FDI muscle. Our study suggests that the cerebellum may play an important role in selective tonic finger movement by reducing its inhibition in the motor cortex only for the relevant agonist muscle.

  2. Bifurcated Bicipital Aponeurosis Giving Origin to Flexor and Extensor Muscles of the Forearm – A Case Report

    OpenAIRE

    Nayak, Satheesha B; Swamy, Ravindra S.; Shetty, Prakashchandra; Maloor, Prasad A; Dsouza, Melanie R

    2016-01-01

    Bicipital aponeurosis is usually attached to the antebrachial fascia on the medial side of forearm and to posterior border of ulna assisting in the supination of the forearm along with biceps brachii muscle. Variations in the bicipital aponeurosis may lead to neurovascular compression as reported earlier. In the present case, the bicipital aponeurosis had two slips i.e. medial and lateral. Medial slip gave origin to some fibers of pronator teres and flexor carpi radialis and the lateral slip ...

  3. Epifascial accessory palmaris longus muscle.

    Science.gov (United States)

    Tiengo, Cesare; Macchi, Veronica; Stecco, Carla; Bassetto, Franco; De Caro, Raffaele

    2006-09-01

    In hand reconstructive surgery the palmaris longus muscle is one of the most utilized donor site for tendon reconstruction procedures. However, its anatomic position is variable and anatomic variations may be responsible for median nerve compression. We report the case of a 40-year-old, right-handed woman, who presented with numbness and paresthesias in the palm and in the flexor aspect of the first, second, and third fingers of her right hand for the preceding 5 months, coinciding with increase of office work (typing). The clinical examination and radiological investigations (ultrasound and magnetic resonance) revealed a subcutaneous mass (15 mm x 2.3 mm x 6 cm), with a lenticular shape and definite edges at the level of the volar aspect of the distal third of the forearm. The fine-needle aspiration biopsy revealed the presence of striated muscle fibers. During surgery, a muscle belly was found in the epifascial plane. This muscle originated from subcutaneous septa in the middle forearm and inserted on to the superficial palmar aponeurosis with fine short tendon fibers. Exposure of the antebrachial fascia did not reveal any area of weakness or muscle herniation. The palmaris longus tendon, flexor digitorum superficialis tendons, and flexor carpi radialis tendon showed usual topography under the antebrachial fascia. The accessory muscle was excised and histology revealed unremarkable striated muscle fibers, limited by a thin connective sheath. The presence of an accessory palmaris longus (APL) located in the epifascial plane could be ascribed to an unusual migration of myoblasts during the morphogenesis. Although extremely rare, APL is worth bearing in mind as a possible cause of median nerve compression and etiology of a volar mass in the distal forearm.

  4. Different motor learning effects on excitability changes of motor cortex in muscle contraction state.

    Science.gov (United States)

    Sugawara, Kenichi; Tanabe, Shigeo; Suzuki, Tomotaka; Higashi, Toshio

    2013-09-01

    We aimed to investigate whether motor learning induces different excitability changes in the human motor cortex (M1) between two different muscle contraction states (before voluntary contraction [static] or during voluntary contraction [dynamic]). For the same, using motor evoked potentials (MEPs) obtained by transcranial magnetic stimulation (TMS), we compared excitability changes during these two states after pinch-grip motor skill learning. The participants performed a force output tracking task by pinch grip on a computer screen. TMS was applied prior to the pinch grip (static) and after initiation of voluntary contraction (dynamic). MEPs of the following muscles were recorded: first dorsal interosseous (FDI), thenar muscle (Thenar), flexor carpi radialis (FCR), and extensor carpi radialis (ECR) muscles. During both the states, motor skill training led to significant improvement of motor performance. During the static state, MEPs of the FDI muscle were significantly facilitated after motor learning; however, during the dynamic state, MEPs of the FDI, Thenar, and FCR muscles were significantly decreased. Based on the results of this study, we concluded that excitability changes in the human M1 are differentially influenced during different voluntary contraction states (static and dynamic) after motor learning.

  5. A comparison of surgeon's postural muscle activity during robotic-assisted and laparoscopic rectal surgery.

    Science.gov (United States)

    Szeto, Grace P Y; Poon, Jensen T C; Law, Wai-Lun

    2013-09-01

    This study compared the muscular activity in the surgeon's neck and upper limbs during robotic-assisted laparoscopic (R-Lap) surgery and conventional laparoscopic (C-Lap) surgery. Two surgeons performed the same procedure of R-Lap and C-Lap low anterior resection, and real-time surface electromyography was recorded in bilateral cervical erector spinae, upper trapezius (UT) and anterior deltoid muscles for over 60 min in each procedure. In one surgeon, forearm muscle activities were also recorded during robotic surgery. Similar levels of cervical muscle activity were demonstrated in both types of surgery. One surgeon showed much higher activity in the left UT muscle during robotic surgery. In the second surgeon, C-Lap was associated with much higher levels of muscle activity in both UT muscles. This may be related to the bilateral abducted arm posture required in maneuvering the laparoscopic instruments. In the forearm region, the "ulnaris" muscles for wrist flexion and extension bilaterally showed high amplitudes during robotic-assisted surgery. Robotic-assisted surgery seemed to demand a higher level of muscle work in the forearm region while greater efforts of shoulder muscles were involved during laparoscopic surgery. There are also individual variations in postural habits and motor control that can affect the muscle activation patterns. This study demonstrated a method of objectively examining the surgeon's physical workload during real-time surgery in the operating theatre, and further research should explore the surgeon's workload in a larger group of surgeons performing different surgical procedures.

  6. Digital image analysis of striated skeletal muscle tissue injury during reperfusion after induced ischemia

    Science.gov (United States)

    Rosero Salazar, Doris Haydee; Salazar Monsalve, Liliana

    2015-01-01

    Conditions such as surgical procedures or vascular diseases produce arterial ischemia and reperfusion injuries, which generate changes in peripheral tissues and organs, for instance, in striated skeletal muscle. To determine such changes, we conducted an experimental method in which 42 male Wistar rat were selected, to be undergone to tourniquet application on the right forelimb and left hind limb, to induce ischemia during one and three hours, followed by reperfusion periods starting at one hour and it was prolonged up to 32 days. Extensor carpi radialis longus and soleus respectively, were obtained to be processed for histochemical and morphometric analysis. By means of image processing and detection of regions of interest, variations of areas occupied by muscle fibers and intramuscular extracellular matrix (IM-ECM) throughout reperfusion were observed. In extensor carpi radialis longus, results shown reduction in the area occupied by muscle fibers; this change is significant between one hour and three hours ischemia followed by 16 hours, 48 hours and 32 days reperfusión (p˂0.005). To compare only periods of reperfusión that continued to three hours ischemia, were found significant differences, as well. For area occupied by IM-ECM, were identified increments in extensor carpi radialis longus by three hours ischemia and eight to 16 days reperfusion; in soleus, was observed difference by one hour ischemia with 42 hours reperfusion, and three hours ischemia followed by four days reperfusion (p˂0.005). Skeletal muscle develops adaptive changes in longer reperfusion, to deal with induced injury. Descriptions beyond 32 days reperfusion, can determine recovering normal pattern.

  7. Upper limb muscle imbalance in tennis elbow: a functional and electromyographic assessment.

    Science.gov (United States)

    Alizadehkhaiyat, Omid; Fisher, Anthony C; Kemp, Graham J; Vishwanathan, Karthik; Frostick, Simon P

    2007-12-01

    The purpose of this study was to investigate strength, fatigability, and activity of upper limb musculature to elucidate the role of muscular imbalance in the pathophysiology of tennis elbow. Sixteen patients clinically diagnosed with tennis elbow, recruited from a university hospital upper limb orthopedic clinic, were compared with 16 control subjects with no history of upper limb musculoskeletal problem, recruited from university students and staff. Muscle strength was measured for grip, metacarpophalangeal, wrist, and shoulder on both sides. Electromyographic activity (RMS amplitude) and fatigue characteristics (median frequency slope) of five forearm and two shoulder muscles were measured during isometric contraction at 50% maximum voluntary contraction. All strength measurements showed dominance difference in C, but none in TE. In tennis elbow compared to controls, hand/wrist and shoulder strength and extensor carpi radialis (ECR) activity were reduced (p imbalance among forearm muscles (reduced extensor carpi radialis activity) in tennis elbow, probably due to protective pain-related inhibition, could lead to a widespread upper limb muscle imbalance.

  8. Hand movements classification for myoelectric control system using adaptive resonance theory.

    Science.gov (United States)

    Jahani Fariman, H; Ahmad, Siti A; Hamiruce Marhaban, M; Alijan Ghasab, M; Chappell, Paul H

    2016-03-01

    This research proposes an exploratory study of a simple, accurate, and computationally efficient movement classification technique for prosthetic hand application. Surface myoelectric signals were acquired from the four muscles, namely, flexor carpi ulnaris, extensor carpi radialis, biceps brachii, and triceps brachii, of four normal-limb subjects. The signals were segmented, and the features were extracted with a new combined time-domain feature extraction method. Fuzzy C-means clustering method and scatter plot were used to evaluate the performance of the proposed multi-feature versus Hudgins' multi-feature. The movements were classified with a hybrid Adaptive Resonance Theory-based neural network. Comparative results indicate that the proposed hybrid classifier not only has good classification accuracy (89.09%) but also a significantly improved computation time.

  9. [Experience in using xeomin in the treatment of arm and hand spasticity in the early rehabilitation phase of stroke].

    Science.gov (United States)

    Kostenko, E V; Petrova, L V; Ganzhula, P A; Lisenker, L N; Otcheskaia, O V; Khozova, A A; Boĭko, A N

    2012-01-01

    To reduce arm and hand spasticity, 28 patients in the early rehabilitation phase of ischemic hemisphere stroke received injections of the botulinum toxin A preparation xeomin in the content of complex rehabilitation programs. The following muscles: m. biceps brachii, m. flexor digitorum profundus, m. flexor digitorum superficialis, m. flexor carpi ulnaris, m. flexor carpi radialis were injected according to standard scheme. The total dose of drug was 200U in moderate (2-3 scores on the Ashworth scale) and 300U in marked (3-4 scores on the Ashworth scale) spasticity. Efficacy and safety of treatment was assessed at baseline and 2, 4, 8, 12, 16 weeks after injections. Xeomin significantly (prehabilitation efficiency. The treatment with xeomin was safe, no serious side-effects were found.

  10. Changes of muscular load with aging in the motion of pulling up disposable diapers.

    Science.gov (United States)

    Yoto, Tsuyoshi Yi; Sakuragawa, Satoshi; Suzuki, Taka-aki; Tamura, Hisae; Yamaki, Rumi; Fujioka, Yoshihisa; Katsuura, Tetsuo

    2010-01-01

    To elucidate how aging affects the muscular load required for pulling up pants-style disposable diapers, and why some elderly people cannot pull up the rear of their disposable diapers well, we evaluated the electromyogram (EMG) of 8 young subjects (21.5+/-1.5 years) and 7 elderly subjects (71.6+/-6.1 years). EMG was measured for four muscles--biceps brachii, deltoid, brachioradialis, and flexor carpi ulnaris. We evaluated the muscular load during a series of motions for pulling a disposable diaper up at the front and the rear of the body using an EMG-Video Synchronous Split Method. The analysis revealed that the front and the rear integral EMG of elderly subjects were both significantly larger than those of young subjects for all four muscles. For the deltoid and flexor carpi ulnaris muscles, the maximum amplitude of EMG when pulling up the rear of the disposable diapers was significantly larger in the elderly subjects than the young ones. These results suggest that the muscular load involved in pulling up the rear of disposable diapers may increase due to changes in body habitus caused by aging. Since muscular strength decreases with age, it seems likely that the elderly individuals will eventually be unable to pull up the rear of their diapers.

  11. Anatomical variation of radial wrist extensor muscles: a study in cadavers

    Directory of Open Access Journals (Sweden)

    Soubhagya Ranjan Nayak

    2008-01-01

    Full Text Available OBJECTIVE: The tendons of the extensor carpi radialis longus and brevis muscles are quite useful in tendon transfer, such as in correction of finger clawing and restoration of thumb opposition. Knowledge of additional radial wrist extensor muscle bellies with independent tendons is useful in the above-mentioned surgical procedures. METHODS: The skin, subcutaneous tissue, and antebrachial fascia of 48 (24 on the right side and 24 on left side male upper limb forearms were dissected. The following aspects were then analyzed: (a the presence of additional muscle bellies of radial wrist extensors, (b the origin and insertion of the additional muscle, and (c measurements of the muscle bellies and their tendons. RESULTS: Five out of 48 upper limbs (10.41% had additional radial wrist extensors; this occurred in 3 out of 24 left upper limbs (12.5% and 2 out of 24 right upper limbs (8.3%. In one of the right upper limbs, two additional muscles were found. The length and width of each additional muscle belly and its tendon ranged between 2 - 15cm by 0.35 - 6.4cm and 2.8 - 20.8cm by 0.2 0.5cm, respectively. The additional radial wrist extensor tendons in our study basically originated either from the extensor carpi radialis longus or brevis muscles and were inserted at the base of the 2nd or 3rd metacarpal bone. CONCLUSION: The present study will inform surgeons about the different varieties of additional radial wrist extensors and the frequency of their occurrence.

  12. Stenosing tenosynovitis

    OpenAIRE

    Vuillemin, V.; Guerini, H.; Bard, H; Morvan, G.

    2012-01-01

    Tenosynovitis refers to an inflammatory condition involving the synovial sheath of a tendon. Stenosing tenosynovitis is a peculiar entity caused by multiple factors, including local anatomy, mechanical factors, and hormonal factors. The main forms include de Quervain tendinopathy; trigger finger (stenosing tenosynovitis involving the flexor digitorum tendons); stenosing tenosynovitis of the extensor carpi ulnaris, extensor carpi radialis, or extensor comunis tendons; stenosing tenosynovitis o...

  13. Origins and branchings of the brachial plexus of the gray brocket deer Mazama gouazoubira (Artiodactyla: Cervidae

    Directory of Open Access Journals (Sweden)

    Lucélia Gonçalves Vieira

    2013-03-01

    Full Text Available The brachial plexus is a set of nerves originated in the cervicothoracic medular region which innervates the thoracic limb and its surroundings. Its study in different species is important not only as a source of morphological knowledge, but also because it facilitates the diagnosis of neuromuscular disorders resulting from various pathologies. This study aimed to describe the origins and branchings of the brachial plexus of Mazama gouazoubira. Three specimens were used, belonging to the scientific collection of the Laboratory for Teaching and Research on Wild Animals of Universidade Federal de Uberlandia (UFU; they were fixed in 3.7% formaldehyde and dissected. In M. gouazoubira, the brachial plexus resulted from connections between the branches of the three last cervical spinal nerves, C6, C7, C8, and the first thoracic one, T1, and it had as derivations the nerves suprascapular, cranial and caudal subscapular, axillary, musculocutaneous, median, ulnar, radial, pectoral, thoracodorsal, long thoracic and lateral thoracic. The muscles innervated by the brachial plexus nerves were the supraspinatus, infraspinatus, subscapularis, teres major, teres minor, deltoid, cleidobrachial, coracobrachialis, biceps brachialis, brachial, triceps brachialis, anconeus, flexor digitorum superficialis, flexor digitorum profundus, flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis, lateral ulnar, extensor carpi obliquus, extensor digitorum, superficial pectoral, deep pectoral, ventral serratus, and external oblique abdominal.

  14. An analysis of motor unit firing pattern during sustained low force contraction in fatigued muscle.

    Science.gov (United States)

    Olsen, H B; Christensen, H; Søgaard, K

    2001-01-01

    In the present study motor unit (MU) firing pattern was analysed during long-term static contraction in order to see if fatigue would induce rotation of activity between different MU. Surface as well as intramuscular EMG were obtained from ten subjects during a sustained hand lift for 5 minutes after performance of a 30% MVC fatiguing contraction of the extensor carpi radialis muscle. A newly developed decomposition program constituted a powerful tool to obtain detailed knowledge of long term activity pattern of MU during low force contractions. Although the muscle was highly fatigued the majority of MU showed a continuous firing pattern after recruitment and no clear incidences of rotation were found for any of the subjects. Therefore, long term, low force contractions, as performed during many occupational work tasks, may involve continuous activation of the low threshold MU and this could have mechanical as well as metabolic implications for these muscle fibers.

  15. Muscle Disorders

    Science.gov (United States)

    Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even ...

  16. Muscle Cramps

    Science.gov (United States)

    Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They often occur ... minutes. It is a very common muscle problem. Muscle cramps can be caused by nerves that malfunction. Sometimes ...

  17. Modification of motor cortex excitability during muscle relaxation in motor learning.

    Science.gov (United States)

    Sugawara, Kenichi; Tanabe, Shigeo; Suzuki, Tomotaka; Saitoh, Kei; Higashi, Toshio

    2016-01-01

    We postulated that gradual muscle relaxation during motor learning would dynamically change activity in the primary motor cortex (M1) and modify short-interval intracortical inhibition (SICI). Thus, we compared changes in M1 excitability both pre and post motor learning during gradual muscle relaxation. Thirteen healthy participants were asked to gradually relax their muscles from an isometric right wrist extension (30% maximum voluntary contraction; MVC) using a tracking task for motor learning. Single or paired transcranial magnetic stimulation (TMS) was applied at either 20% or 80% of the downward force output during muscle release from 30% MVC, and we compared the effects of motor learning immediately after the 1st and 10th blocks. Motor-evoked potentials (MEPs) from the extensor and flexor carpi radialis (ECR and FCR) were then measured and compared to evaluate their relationship before and after motor learning. In both muscles and each downward force output, motor cortex excitability during muscle relaxation was significantly increased following motor learning. In the ECR, the SICI in the 10th block was significantly increased during the 80% waveform decline compared to the SICI in the 1st block. In the FCR, the SICI also exhibited a greater inhibitory effect when muscle relaxation was terminated following motor learning. During motor training, acquisition of the ability to control muscle relaxation increased the SICI in both the ECR and FCR during motor termination. This finding aids in our understanding of the cortical mechanisms that underlie muscle relaxation during motor learning.

  18. Choosing the Optimal Trigger Point for Analysis of Movements after Stroke Based on Magnetoencephalographic Recordings

    Directory of Open Access Journals (Sweden)

    Guido Waldmann

    2010-01-01

    Full Text Available The aim of this study was to select the optimal procedure for analysing motor fields (MF and motor evoked fields (MEF measured from brain injured patients. Behavioural pretests with patients have shown that most of them cannot stand measurements longer than 30 minutes and they also prefer to move the hand with rather short breaks between movements. Therefore, we were unable to measure the motor field (MF optimally. Furthermore, we planned to use MEF to monitor cortical plasticity in a motor rehabilitation procedure. Classically, the MF analysis refers to rather long epochs around the movement onset (M-onset. We shortened the analysis epoch down to a range from 1000 milliseconds before until 500 milliseconds after M-onset to fulfil the needs of the patients. Additionally, we recorded the muscular activity (EMG by surface electrodes on the extensor carpi ulnaris and flexor carpi ulnaris muscles. Magnetoencephalographic (MEG data were recorded from 9 healthy subjects, who executed horizontally brisk extension and flexion in the right wrist. Significantly higher MF dipole strength was found in data based on EMG-onset than in M-onset based data. There was no difference in MEF I dipole strength between the two trigger latencies. In conclusion, we recommend averaging in respect to the EMG-onset for the analysis of both components MF as well as MEF.

  19. Skeletal muscle

    Science.gov (United States)

    There are approximately 650-850 muscles in the human body these include skeletal (striated), smooth and cardiac muscle. The approximation is based on what some anatomists consider separate muscle or muscle systems. Muscles are classified based on their anatomy (striated vs. smooth) and if they are v...

  20. Muscle Deoxygenation Causes Muscle Fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D.

    1999-01-01

    Muscle fatigue is a common musculoskeletal disorder in the work place, and may be a harbinger for more disabling cumulative trauma disorders. Although the cause of fatigue is multifactorial, reduced blood flow and muscle oxygenation may be the primary factor in causing muscle fatigue during low intensity muscle exertion. Muscle fatigue is defined as a reduction in muscle force production, and also occurs among astronauts who are subjected to postural constraints while performing lengthy, repetitive tasks. The objectives of this research are to: 1) develop an objective tool to study the role of decreased muscle oxygenation on muscle force production, and 2) to evaluate muscle fatigue during prolonged glovebox work.

  1. Muscle disorder

    Science.gov (United States)

    Myopathic changes; Myopathy; Muscle problem ... Blood tests sometimes show abnormally high muscle enzymes. If a muscle disorder might also affect other family members, genetic testing may be done. When someone has symptoms and signs ...

  2. Bifurcated Bicipital Aponeurosis Giving Origin to Flexor and Extensor Muscles of the Forearm - A Case Report.

    Science.gov (United States)

    Nayak, Satheesha B; Swamy, Ravindra S; Shetty, Prakashchandra; Maloor, Prasad A; Dsouza, Melanie R

    2016-02-01

    Bicipital aponeurosis is usually attached to the antebrachial fascia on the medial side of forearm and to posterior border of ulna assisting in the supination of the forearm along with biceps brachii muscle. Variations in the bicipital aponeurosis may lead to neurovascular compression as reported earlier. In the present case, the bicipital aponeurosis had two slips i.e. medial and lateral. Medial slip gave origin to some fibers of pronator teres and flexor carpi radialis and the lateral slip gave origin to some fibers of brachioradialis. Such unusual slips of bicipital aponeurosis may distribute the stress concentration and may work in different directions affecting the supination of forearm by biceps brachii muscle and bicipital aponeurosis.

  3. Effects of vibratory stimulations on maximal voluntary isometric contraction from delayed onset muscle soreness.

    Science.gov (United States)

    Koh, Hyung-Woo; Cho, Sung-Hyoun; Kim, Cheol-Yong; Cho, Byung-Jun; Kim, Jin-Woo; Bo, Kak Hwang

    2013-09-01

    [Purpose] The aim of this study was to investigate the effect of vibratory stimulation on maximal voluntary isometric contraction (MVIC) from delayed onset muscle soreness (DOMS). [Subjects] Sixty healthy adults participated in this study. The exclusion criteria were orthopedic or neurologic disease. [Methods] The researchers induced DOMS in the musculus extensor carpi radialis longus of each participant. Subjects in the control group received no treatment. The ultrasound group received ultrasound treatment (intensity, 1.0 W/cm(2;) frequency 1 MHz; time, 10 minutes). The vibration group received vibration stimulation (frequency, 20 MHz; time, 10 minutes). Maximal voluntary isometric contraction (MVIC) was recorded at baseline, immediately after exercise, and 24, 48, and 72 hours after exercise. [Results] MVIC measurements showed statistically significant differences in the vibration group compared with the control group. [Conclusion] Vibratory stimulation had a positive effect on recovery of muscle function from DOMS.

  4. Reversal of TMS-induced motor twitch by training is associated with a reduction in excitability of the antagonist muscle

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    Fregni Felipe

    2011-08-01

    Full Text Available Abstract Background A single session of isolated repetitive movements of the thumb can alter the response to transcranial magnetic stimulation (TMS, such that the related muscle twitch measured post-training occurs in the trained direction. This response is attributed to transient excitability changes in primary motor cortex (M1 that form the early part of learning. We investigated; (1 whether this phenomenon might occur for movements at the wrist, and (2 how specific TMS activation patterns of opposing muscles underlie the practice-induced change in direction. Methods We used single-pulse suprathreshold TMS over the M1 forearm area, to evoke wrist movements in 20 healthy subjects. We measured the preferential direction of the TMS-induced twitch in both the sagittal and coronal plane using an optical goniometer fixed to the dorsum of the wrist, and recorded electromyographic (EMG activity from the flexor carpi radialis (FCR and extensor carpi radialis (ECR muscles. Subjects performed gentle voluntary movements, in the direction opposite to the initial twitch for 5 minutes at 0.2 Hz. We collected motor evoked potentials (MEPs elicited by TMS at baseline and for 10 minutes after training. Results Repetitive motor training was sufficient for TMS to evoke movements in the practiced direction opposite to the original twitch. For most subjects the effect of the newly-acquired direction was retained for at least 10 minutes before reverting to the original. Importantly, the direction change of the movement was associated with a significant decrease in MEP amplitude of the antagonist to the trained muscle, rather than an increase in MEP amplitude of the trained muscle. Conclusions These results demonstrate for the first time that a TMS-twitch direction change following a simple practice paradigm may result from reduced corticospinal drive to muscles antagonizing the trained direction. Such findings may have implications for training paradigms in

  5. Treatment of cubital tunnel syndrome with ulnar nerve anterior submuscular transposition and medial epicondyle muscle group in situ reconstruction via a bone tunnel%尺神经肌下前置肱骨内上髁肌群经骨道原位重建治疗肘管综合征

    Institute of Scientific and Technical Information of China (English)

    张小路; 林其仁

    2014-01-01

    Objective To investigate the clinical effectiveness of treating moderate to severe cubital tunnel syndrome with ulnar nerve decompression,anterior submuscular transposition and medial epicondyle muscle group in situ reconstruction via a bone tunnel.Methods The clinical data of 45 cases of moderate to severe cubital tunnel syndrome diagnosed between January 2005 and October 2012 were analyzed.The ulnar nerve was decompressed and its perfnsion by the superior ulnar collateral artery was observed under the surgical microscope intraoperatively.After ulnar nerve was transposed anteriorly,the detached medial epicondyle muscle group was reconstructed in situ through a bone tuunel under direct view.The size of the new ulnar nerve tunnel and mobility of the ulnar nerve were observed.Postoperative recovery was follow-up including pain,sensation,muscular atrophy recovery,claw hand,grip strength,wrist flexion and forearm pronation.Results All 45 cases were follow-up for 6 to 18 months.Intraoperative microscopic observation showed good ulnar nerve perfusion by the superior ulnar collateral artery.Reattachment of the medial epicondyle muscle group was secure.The newly formed cubital tunnel could allow an 8 mm dilator without tension in elbow full extension position.Ulnar nerve could glide freely upon elbow flexion and extension.According to the cubital tunnel syndrome function evaluation standard suggested by Gu Yudong,the results were graded as excellent in 20 cases,good in 17 cases,and fair in 8 cases.The overall excellent and good rate was 82.22%.Wrist flexion and forearm pronation force recovered to preoperative level in all the patients 3 months after the operation.Conclusion Including superior ulnar collateral artery in the anterior transposition of the ulnar nerve provides good blood supply to the nerve and benefits nerve recovery.In situ reconstruction of the medial epicondyle muscle group through a bone tunnel puts the ulnar nerve anderneath flexor carpi ulnaris and

  6. Ultrasound of the elbow with emphasis on detailed assessment of ligaments, tendons, and nerves

    Energy Technology Data Exchange (ETDEWEB)

    De Maeseneer, Michel, E-mail: Michel.demaeseneer@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Brigido, Monica Kalume, E-mail: Mbrigido@med.umich.edu [Department of Radiology, University of Michigan, Ann Arbor, MI (United States); Antic, Marijana, E-mail: Misscroa@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Lenchik, Leon, E-mail: Llenchik@wakehealth.edu [Department of Radiology, Wake Forest University, Winston-Salem, NC (United States); Milants, Annemieke, E-mail: Annemieke.Milants@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Vereecke, Evie, E-mail: Evie.Vereecke@kuleuven-kulak.be [Department of Anatomy, KULAK, Katholieke Universiteit Leuven, Campus Kortrijk, Kortrijk (Belgium); Jager, Tjeerd [Aalsters Stedelijk Ziekenhuis, Aalst (Belgium); Shahabpour, Maryam, E-mail: Maryam.Shahabpour@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium)

    2015-04-15

    Highlights: •Medial and lateral tendons: the different muscles forming these tendons can be followed up to the insertion. The imaging anatomy is reviewed. •Medial and lateral ligaments: the anatomy is complex and specialized imaging planes and arm positions are necessary for accurate assessment. •Biceps tendon: the anatomy of the distal biceps and lacertus fibrosus are discussed and illustrated with cadaveric correlation. •US imaging of the nerves about the elbow and visualization of the possible compression points is discussed. -- Abstract: The high resolution and dynamic capability of ultrasound make it an excellent tool for assessment of superficial structures. The ligaments, tendons, and nerves about the elbow can be fully evaluated with ultrasound. The medial collateral ligament consists of an anterior and posterior band that can easily be identified. The lateral ligament complex consists of the radial collateral ligament, ulnar insertion of the annular ligament, and lateral ulnar collateral ligament, easily identified with specialized probe positioning. The lateral ulnar collateral ligament can best be seen in the cobra position. On ultrasound medial elbow tendons can be followed nearly up to their common insertion. The pronator teres, flexor carpi radialis, palmaris longus, and flexor digitorum superficialis can be identified. The laterally located brachioradialis and extensor carpi radialis longus insert on the supracondylar ridge. The other lateral tendons can be followed up to their common insertion on the lateral epicondyle. The extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi, and extensor carpi ulnaris can be differentiated. The distal biceps tendon is commonly bifid. For a complete assessment of the distal biceps tendon specialized views are necessary. These include an anterior axial approach, medial and lateral approach, and cobra position. In the cubital tunnel the ulnar nerve is covered by the ligament of Osborne

  7. Muscle fatigue based evaluation of bicycle design.

    Science.gov (United States)

    Balasubramanian, V; Jagannath, M; Adalarasu, K

    2014-03-01

    Bicycling posture leads to considerable discomfort and a variety of chronic injuries. This necessitates a proper bicycle design to avoid injuries and thereby enhance rider comfort. The objective of this study was to investigate the muscle activity during cycling on three different bicycle designs, i.e., rigid frame (RF), suspension (SU) and sports (SP) using surface electromyography (sEMG). Twelve male volunteers participated in this study. sEMG signals were acquired bilaterally from extensor carpi radialis (ECR), trapezius medial (TM), latissimus dorsi medial (LDM) and erector spinae (ES), during 30 min of cycling on each bicycle and after cycling. Time domain (RMS) and frequency domain (MPF) parameters were extracted from acquired sEMG signals. From the sEMG study, it was found that the fatigue in right LDM and ES were significantly (p bicycle. This was corroborated by a psychophysical assessment based on RBG pain scale. The study also showed that there was a significantly lesser fatigue with the SU bicycle than the RF and SP bicycles.

  8. A rare variant of the ulnar artery with important clinical implications: a case report

    Directory of Open Access Journals (Sweden)

    Casal Diogo

    2012-11-01

    Full Text Available Abstract Background Variations in the major arteries of the upper limb are estimated to be present in up to one fifth of people, and may have significant clinical implications. Case presentation During routine cadaveric dissection of a 69-year-old fresh female cadaver, a superficial brachioulnar artery with an aberrant path was found bilaterally. The superficial brachioulnar artery originated at midarm level from the brachial artery, pierced the brachial fascia immediately proximal to the elbow, crossed superficial to the muscles that originated from the medial epicondyle, and ran over the pronator teres muscle in a doubling of the antebrachial fascia. It then dipped into the forearm fascia, in the gap between the flexor carpi radialis and the palmaris longus. Subsequently, it ran deep to the palmaris longus muscle belly, and superficially to the flexor digitorum superficialis muscle, reaching the gap between the latter and the flexor carpi ulnaris muscle, where it assumed is usual position lateral to the ulnar nerve. Conclusion As far as the authors could determine, this variant of the superficial brachioulnar artery has only been described twice before in the literature. The existence of such a variant is of particular clinical significance, as these arteries are more susceptible to trauma, and can be easily confused with superficial veins during medical and surgical procedures, potentially leading to iatrogenic distal limb ischemia.

  9. Bifurcated Bicipital Aponeurosis Giving Origin to Flexor and Extensor Muscles of the Forearm – A Case Report

    Science.gov (United States)

    Nayak, Satheesha B; Shetty, Prakashchandra; Maloor, Prasad A; Dsouza, Melanie R

    2016-01-01

    Bicipital aponeurosis is usually attached to the antebrachial fascia on the medial side of forearm and to posterior border of ulna assisting in the supination of the forearm along with biceps brachii muscle. Variations in the bicipital aponeurosis may lead to neurovascular compression as reported earlier. In the present case, the bicipital aponeurosis had two slips i.e. medial and lateral. Medial slip gave origin to some fibers of pronator teres and flexor carpi radialis and the lateral slip gave origin to some fibers of brachioradialis. Such unusual slips of bicipital aponeurosis may distribute the stress concentration and may work in different directions affecting the supination of forearm by biceps brachii muscle and bicipital aponeurosis. PMID:27042440

  10. Muscle biopsy

    Science.gov (United States)

    ... Inflammatory diseases of muscle (such as polymyositis or dermatomyositis ) Diseases of the connective tissue and blood vessels ( ... disease that involves inflammation and a skin rash ( dermatomyositis ) Inherited muscle disorder ( Duchenne muscular dystrophy ) Inflammation of ...

  11. Modeling Muscles

    Science.gov (United States)

    Goodwyn, Lauren; Salm, Sarah

    2007-01-01

    Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…

  12. The Effect of Radial Extracorporeal Shock Wave Stimulation on Upper Limb Spasticity in Chronic Stroke Patients: A Single-Blind, Randomized, Placebo-Controlled Study.

    Science.gov (United States)

    Dymarek, Robert; Taradaj, Jakub; Rosińczuk, Joanna

    2016-08-01

    The main purpose of this study was to determine the clinical, electrophysiological and thermal effects of radial extracorporeal shock wave (rESW) stimulation on upper limb muscles affected by spasticity in patients with chronic stroke. Patients included in the study were randomly assigned into the following two groups: 30 patients stimulated with active rESW (A); and 30 patients stimulated with placebo rESW (B). All patients were analyzed using the Modified Ashworth Scale (MAS) to test the spasticity levels of the elbow (E), radio carpal (RC) and fingers (FF) joints; surface electromyography (sEMG) was performed for the resting bioelectrical activity registration of the flexor carpi radialis (FCR) and flexor carpi ulnaris (FCU) muscles; and infrared thermal imaging (IRT) was used to assess the temperature distributions of the carpal flexor muscles (CFM). All assessments were performed at baseline (t0), immediately after rESW (t1) as well as 1 and 24 h following its finalization (t2 and t3). Patients treated with active rESW showed a statistically significant reduction in the MAS score for the RC joint at t1 and for the FF joints at t1, t2 and t3 (p  0.05). Applications of rESW demonstrating positive effects at reducing the level of spastic hypertonia of the upper limb muscles in patients with chronic stroke. ESW treatments should be considered as a potential anti-spastic effect to regulate vasculature.

  13. Temporal modulations of agonist and antagonist muscle activities accompanying improved performance of ballistic movements.

    Science.gov (United States)

    Liang, Nan; Yamashita, Takamasa; Ni, Zhen; Takahashi, Makoto; Murakami, Tsuneji; Yahagi, Susumu; Kasai, Tatsuya

    2008-02-01

    Although many studies have examined performance improvements of ballistic movement through practice, it is still unclear how performance advances while maintaining maximum velocity, and how the accompanying triphasic electromyographic (EMG) activity is modified. The present study focused on the changes in triphasic EMG activity, i.e., the first agonist burst (AG1), the second agonist burst (AG2), and the antagonist burst (ANT), that accompanied decreases in movement time and error. Twelve healthy volunteers performed 100 ballistic wrist flexion movements in ten 10-trial sessions under the instruction to "maintain maximum velocity throughout the experiment and to stop the limb at the target as fast and accurately as possible". Kinematic parameters (position and velocity) and triphasic EMG activities from the agonist (flexor carpi radialis) and antagonist (extensor carpi radialis) muscles were recorded. Comparison of the results obtained from the first and the last 10 trials, revealed that movement time, movement error, and variability of amplitudes reduced with practice, and that maximum velocity and time to maximum velocity remained constant. EMG activities showed that AG1 and AG2 durations were reduced, whereas ANT duration did not change. Additionally, ANT and AG2 latencies were reduced. Integrated EMG of AG1 was significantly reduced as well. Analysis of the alpha angle (an index of the rate of recruitment of the motoneurons) showed that there was no change in either AG1 or AG2. Correlation analysis of alpha angles between these two bursts further revealed that the close relationship of AG1 and AG2 was kept constant through practice. These findings led to the conclusion that performance improvement in ballistic movement is mainly due to the temporal modulations of agonist and antagonist muscle activities when maximum velocity is kept constant. Presumably, a specific strategy is consistently applied during practice.

  14. The Paley ulnarization of the carpus with ulnar shortening osteotomy for treatment of radial club hand

    Directory of Open Access Journals (Sweden)

    Paley Dror

    2017-01-01

    Full Text Available Recurrent deformity from centralization and radialization led to the development in 1999 of a new technique by the author called ulnarization. This method is performed through a volar approach in a vascular and physeal sparing fashion. It biomechanically balances the muscle forces on the wrist by dorsally transferring the flexor carpi ulnaris (FCU from a deforming to a corrective force. The previous problems of a prominent bump from the ulnar head and ulnar deviation instability were solved by acutely shortening the diaphysis and by temporarily fixing the station of the carpus to the ulnar head at the level of the scaphoid. This is the first report of this modified Paley ulnarization method, which the author considers a significant improvement over his original procedure.

  15. The Paley ulnarization of the carpus with ulnar shortening osteotomy for treatment of radial club hand

    Science.gov (United States)

    Paley, Dror

    2017-01-01

    Recurrent deformity from centralization and radialization led to the development in 1999 of a new technique by the author called ulnarization. This method is performed through a volar approach in a vascular and physeal sparing fashion. It biomechanically balances the muscle forces on the wrist by dorsally transferring the flexor carpi ulnaris (FCU) from a deforming to a corrective force. The previous problems of a prominent bump from the ulnar head and ulnar deviation instability were solved by acutely shortening the diaphysis and by temporarily fixing the station of the carpus to the ulnar head at the level of the scaphoid. This is the first report of this modified Paley ulnarization method, which the author considers a significant improvement over his original procedure. PMID:28120747

  16. Long-lasting modulation of human motor cortex following prolonged transcutaneous electrical nerve stimulation (TENS) of forearm muscles: evidence of reciprocal inhibition and facilitation.

    Science.gov (United States)

    Tinazzi, Michele; Zarattini, Stefano; Valeriani, Massimiliano; Romito, Silvia; Farina, Simona; Moretto, Giuseppe; Smania, Nicola; Fiaschi, Antonio; Abbruzzese, Giovanni

    2005-03-01

    Several lines of evidence indicate that motor cortex excitability can be modulated by manipulation of afferent inputs, like peripheral electrical stimulation. Most studies in humans mainly dealt with the effects of prolonged low-frequency peripheral nerve stimulation on motor cortical excitability, despite its being known from animal studies that high-frequency stimulation can also result in changes of the cortical excitability. To investigate the possible effects of high-frequency peripheral stimulation on motor cortical excitability we recorded motor-evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) of the left motor cortex from the right flexor carpi radialis (FCR), extensor carpi radialis (ECR), and first dorsal interosseous (FDI) in normal subjects, before and after transcutaneous electrical nerve stimulation (TENS) of 30 min duration applied over the FCR. The amplitude of MEPs from the FRC was significantly reduced from 10 to 35 min after TENS while the amplitude of MEPs from ECR was increased. No effects were observed in the FDI muscle. Indices of peripheral nerve (M-wave) and spinal cord excitability (H waves) did not change throughout the experiment. Electrical stimulation of the lateral antebrachial cutaneous nerve has no significant effect on motor cortex excitability. These findings suggest that TENS of forearm muscles can induce transient reciprocal inhibitory and facilitatory changes in corticomotoneuronal excitability of forearm flexor and extensor muscles lasting several minutes. These changes probably may occur at cortical site and seem to be mainly dependent on stimulation of muscle afferents. These findings might eventually lead to practical applications in rehabilitation, especially in those syndromes in which the excitatory and inhibitory balance between agonist and antagonist is severely impaired, such as spasticity and dystonia.

  17. Changes in contractile properties by androgen hormones in sexually dimorphic muscles of male frogs (Xenopus laevis).

    Science.gov (United States)

    Regnier, M; Herrera, A A

    1993-02-01

    1. Male frogs (Xenopus laevis) were castrated then given either empty or testosterone-filled implants to produce animals with low or high levels of circulating testosterone. Eight weeks later the contractile properties of an androgen-sensitive forelimb flexor, the flexor carpi radialis muscle (FCR), were measured in vitro. Another forelimb flexor muscle, the coracoradialis, and a hindlimb muscle, the iliofibularis, were analysed similarly. 2. Plasma testosterone levels were 0.9 +/- 0.3 ng/ml (+/- S.E.M.) in castrated frogs with blank implants (C) and 61.3 +/- 4.7 ng/ml in castrates with testosterone implants (CT). Unoperated males, sampled at various times of the year, ranged between 10.8 and 51.0 ng/ml. 3. With direct electrical stimulation of the FCR, contraction time of the isometric twitch was not affected by testosterone levels. Relaxation times were affected, however. Half- and 90% relaxation times were 27 and 42% longer, respectively, for CT compared to C muscles. 4. Testosterone also had no effect on the contraction time of twitches elicited by stimulation of the FCR nerve. Half- and 90% relaxation times were 51 and 76% longer, respectively, for CT compared to C muscles. 5. Tetanus tension, elicited by direct stimulation of the FCR at 50 Hz, was 86% greater in CT compared to C muscles. The average cross-sectional area of FCR muscle fibres was 84% greater in CT muscles. These results implied that testosterone treatment had no effect on specific muscle tension. 6. Stimulation of the FCR nerve at 50 Hz resulted in 53% less tension than the same stimulus applied directly to CT muscles. In C muscles the difference was only 14%. This suggested that testosterone treatment reduced synaptic efficacy. 7. In CT muscles, direct or nerve stimulation of fibres in the shoulder region of the FCR elicited twitches that contracted and relaxed more slowly than fibres in the elbow region. In C muscles there was no difference in contraction or relaxation time between fibres in

  18. Muscle atrophy

    Science.gov (United States)

    ... a single nerve, such as carpal tunnel syndrome Guillain-Barre syndrome Nerve damage caused by injury, diabetes, toxins, ... chap 421. Read More Amyotrophic lateral sclerosis (ALS) Guillain-Barré syndrome Hypotonia Muscle cramps Muscular dystrophy Polio Review ...

  19. EMG discharge patterns during human grip movement are task-dependent and not modulated by muscle contraction modes: a transcranial magnetic stimulation (TMS) study.

    Science.gov (United States)

    Anson, J G; Hasegawa, Y; Kasai, T; Latash, M L; Yahagi, S

    2002-05-03

    Our previous study revealed that, during tonic muscle contraction, remarkable functional differences among intrinsic and extrinsic muscles were observed during two different grip movements, i.e., precision and power grips. To verify whether this evidence is true even under the phasic muscle contraction, magnetic stimulation was delivered over the left scalp while a normal human subject performed phasic precision or power grip responses of the right-hand fingers in a simple reaction time (SRT) paradigm. Magnetic stimulation delivered during the latent period revealed different cortico-motoneuronal excitations between the two grip responses. In particular, the contributions of extensor carpi radialis (ECR) muscle were definitely different between the two grip responses, although motor-evoked potentials (MEPs) of first dorsal interosseous (FDI) prior to, and after EMG onset of movement initiation, were not different. These results were similar to previous results obtained during tonic muscle contraction. Thus, we have concluded that the task-dependent EMG discharge pattern in finger manipulation could not be modulated by muscle contraction modes.

  20. Muscle strain (image)

    Science.gov (United States)

    A muscle strain is the stretching or tearing of muscle fibers. A muscle strain can be caused by sports, exercise, a ... something that is too heavy. Symptoms of a muscle strain include pain, tightness, swelling, tenderness, and the ...

  1. Muscular forearm activation in hand-grip tasks with superimposition of mechanical vibrations.

    Science.gov (United States)

    Fattorini, L; Tirabasso, A; Lunghi, A; Di Giovanni, R; Sacco, F; Marchetti, E

    2016-02-01

    The purpose of this paper is to evaluate the muscular activation of the forearm, with or without vibration stimuli at different frequencies while performing a grip tasks of 45s at various level of exerted force. In 16 individuals, 9 females and 7 males, the surface electromyogram (EMG) of extensor carpi radialis longus and the flexor carpi ulnari muscles were assessed. At a short latency from onset EMG, RMS and the level of MU synchronization were assessed to evaluate the muscular adaptations. Whilst a trend of decay of EMG Median frequency (MDFd) was employed as an index of muscular fatigue. Muscular tasks consists of the grip of an instrumented handle at a force level of 20%, 30%, 40%, 60% of the maximum voluntary force. Vibration was supplied by a shaker to the hand in mono-frequential waves at 20, 30, 33 and 40Hz. In relation to EMG, RMS and MU synchronization, the muscular activation does not seem to change with the superimposition of the mechanical vibrations, on the contrary a lower MDFd was observed at 33Hz than in absence of vibration. This suggests an early muscular fatigue induced by vibration due to the fact that 33Hz is a resonance frequency for the hand-arm system.

  2. Surgical correction of ulnar deviation deformity of the wrist in patients with birth brachial plexus palsy sequelae.

    Science.gov (United States)

    Bhardwaj, Praveen; Parekh, Harshil; Venkatramani, Hari; Raja Sabapathy, S

    2015-01-01

    Ulnar deviation deformity of the wrist in patients with birth brachial plexus palsy is an important cosmetic concern among the patients and their relatives; especially in the patients who have recovered the basic limb functions. Though there is ample literature available regarding the management of the shoulder deformity there is paucity of literature regarding management of wrist ulnar deviation deformity. We report our experience with correction of this deformity in five cases with isolated ulnar deviation deformity without forearm rotational deformity or weakness of the wrist muscles. All the patients underwent extensor carpi ulnaris (ECU) to extensor carpi radialis longus (ECRL) tendon transfer. At a minimum of 18 months follow-up all the patients and their families were satisfied with the cosmetic appearance of the limb. Correction of the deformity improves the appearance of the limb, improves self-confidence of the child, and allows them to integrate well into the society. Interestingly, the patients expressed improvement in their grip strength and overall hand function after this surgery. The notable functions which improved were easy reach of the hand-to-mouth for feeding and easy handling of the things requiring bimanual activities. Although the main aim of this operation was to correct the appearance of the hand it was found to be also functionally useful by the patients and hence we are encouraged to report it for wider use. The results were maintained during the follow-up period of as long as 47 months.

  3. Equine postanesthetic forelimb lameness: intracompartmental muscle pressure changes and biochemical patterns.

    Science.gov (United States)

    Lindsay, W A; McDonell, W; Bignell, W

    1980-12-01

    Intracompartmental muscle pressures were recorded from the right and left forelimbs (extensor carpi radialis, triceps brachii) of healthy horses maintained in left lateral recumbency while under deep halothane anesthesia for 180 to 240 minutes. Cardiac output, blood pressure, blood gases, and acid-base status were monitored throughout the anesthesia, and electrolyte levels (Ca2+, P+, K+, Cl-, Na+) and enzyme activities (aspartate aminotransferase (AST), creatine phosphokinase (CPK), and blood lactate) were monitored for 7 days. Postanesthetic forelimb lameness was produced in 5 of the 6 horses with this prolonged anesthetic regime. This lameness was associated with muscle plaque formation and clinical signs which were similar to the forelimb lameness sometimes seen in horses after surgical anesthesia. Plasma protein, serum calcium, plasma sodium, and blood urea nitrogen concentrations did not change, whereas significantly increased hematocrit, plasma potassium, and serum inorganic phosphate values were seen at the end of anesthesia, along with a decrease in plasma chloride values. Blood lactate, serum AST, and serum CPK activities were significantly high in the postanesthetic period, although the sequence of the changes differed. Intracompartmental muscle pressures were higher in the left forelimb adjacent to the floor (contact limb), and in the instance of the triceps of the contact limb, the pressures were sufficiently high (greater than 30 mm of Hg) that they may have compromised capillary blood flow. However, these high intracompartmental muscle pressures did not persist when positional changes of the horses were introduced at the end of the anesthetic period. There was no correlation between the severity of postanesthetic lameness and any of the measured values. The results demonstrate an experimentally induced postanesthetic lameness which was primarily related to the development of a myositis. Although the causative factors of this myositis may be multiple

  4. Shoulder and forearm oxygenation and myoelectric activity in patients with work-related muscle pain and healthy subjects.

    Science.gov (United States)

    Elcadi, Guilherme H; Forsman, Mikael; Aasa, Ulrika; Fahlstrom, Martin; Crenshaw, Albert G

    2013-05-01

    We tested hypotheses of (a) reduced oxygen usage, oxygen recovery, blood flow and oxygen consumption; and (b) increased muscle activity for patients diagnosed with work-related muscle pain (WRMP) in comparison to healthy controls. Oxygenation was measured with near infrared spectroscopy (NIRS), and muscle activity with EMG for the extensor carpi radialis (ECR) and trapezius descendens (TD) muscles. Eighteen patients with diffuse neck-shoulder-arm pain and 17 controls (matched in age and sex) were equipped with NIRS and EMG probes. After determining an individual's maximum voluntary contraction (MVC) force, short-term (20 s) isometric contractions for the ECR and TD of 10, 30, 50 and 70 % MVC generated ∆StO₂ and StO₂% recovery (Rslope) from NIRS, and RMS%max from EMG signals. In addition, upper arm venous (VO) and arterial (AO) occlusions generated slopes of total hemoglobin (HbTslope) and deoxyhemoglobin (HHbslope) for the resting ECR as surrogates of blood flow and oxygen consumption, respectively. Mixed model analyses, t tests, and Mann-Whitney test were used to assess differences between groups. There was no significant difference in MVC between groups for either muscle. Also, ∆StO₂%, Rslope for either muscle, and ECR-HbTslope were not different between groups, thus our hypotheses of reduced oxygen use, recovery, and blood flow for patients were not confirmed. However, patients had a significantly lower ECR-HHbslope confirming our hypothesis of reduced consumption. Further, there was no difference in RMS%max during contractions meaning that the hypothesis of increased activity for patients was not confirmed. When taking into account the number of NIRS variables studied, differences we found between our patient group and healthy controls (i.e., in forearm oxygen consumption and shoulder oxygen saturation level) may be considered modest. Overall our findings may have been impacted by the fact that our patients and controls were similar in muscle strength

  5. Comparison of an intermittent and continuous forearm muscles fatigue protocol with motorcycle riders and control group.

    Science.gov (United States)

    Marina, M; Torrado, P; Busquets, A; Ríos, J G; Angulo-Barroso, R

    2013-02-01

    Motorcycle races' long duration justify the study of forearm muscles fatigue, especially knowing the frequently associated forearm discomfort pathology. Moreover, while continuous fatigue protocols yield unequivocal results, EMG outcomes from an intermittent protocol are quite controversial. This study examined the forearm muscle fatigue patterns produced during these two protocols, comparing riders with a control group, and relating maximal voluntary contraction with EMG parameters (amplitude - NRMS and median frequency - NMF) of both protocols to the forearm discomfort among motorcycle riders. Twenty riders and 39 controls performed in separate days both protocols simulating the braking gesture and posture of a rider. EMG of flexor digitorum superficialis (FS) and carpi radialis (CR) were monitored. CR revealed more differences among protocols and groups compared to FS. The greater CR activation in riders could be interpreted as a neuromotor strategy to improve braking precision. When FS fatigue increased, the control group progressively shift toward a bigger CR activation, adopting an intermuscular activation pattern closer to riders. Despite the absence of NMF decrement throughout the intermittent protocol, which suggest that we should have shorten the recovery times from the actual 1 min, the superior number of rounds performed by the riders proved that this protocol discriminates better riders against controls and is more related to forearm discomfort.

  6. Muscle disease.

    Science.gov (United States)

    Tsao, Chang-Yong

    2014-02-01

    On the basis of strong research evidence, Duchenne muscular dystrophy (DMD), the most common severe childhood form of muscular dystrophy, is an X-linked recessive disorder caused by out-of-frame mutations of the dystrophin gene. Thus, it is classified asa dystrophinopathy. The disease onset is before age 5 years. Patients with DMD present with progressive symmetrical limb-girdle muscle weakness and become wheelchair dependent after age 12 years. (2)(3). On the basis of some research evidence,cardiomyopathy and congestive heart failure are usually seen in the late teens in patients with DMD. Progressive scoliosis and respiratory in sufficiency often develop once wheelchair dependency occurs. Respiratory failure and cardiomyopathy are common causes of death, and few survive beyond the third decade of life. (2)(3)(4)(5)(6)(7). On the basis of some research evidence, prednisone at 0.75 mg/kg daily (maximum dose, 40 mg/d) or deflazacort at 0.9 mg/kg daily (maximum dose, 39 mg/d), a derivative of prednisolone (not available in the United States), as a single morning dose is recommended for DMD patients older than 5 years, which may prolong independent walking from a few months to 2 years. (2)(3)(16)(17). Based on some research evidence, treatment with angiotensin-converting enzyme inhibitors, b-blockers, and diuretics has been reported to be beneficial in DMD patients with cardiac abnormalities. (2)(3)(5)(18). Based on expert opinion, children with muscle weakness and increased serum creatine kinase levels may be associated with either genetic or acquired muscle disorders (Tables 1 and 3). (14)(15)

  7. [Kocher approach to the elbow and its options].

    Science.gov (United States)

    Bartoníček, J; Naňka, O; Tuček, M

    2015-10-01

    The original Kocher approach was published several times in the 18921907 period. It extends in the interval between the extensor carpi ulnaris and the anconeus and consists in subperiostal release of the lateral collateral ligament (LCL), joint capsule and origin of extensors at the lateral epicondyle and their retraction anteriorly, and a similar release of the anconeus from the distal humerus and its reflection posteriorly. This provides an extensive approach to the elbow. Today this approach is described in the textbooks in various modifications that have little in common with the original description except for the fact that dissection is made in the so called Kocher interval between the extensor carpi ulnaris and the anconeus. Therefore it is often called a limited Kocher approach.The study describes our modification of the Kocher approach that we use primarily in fractures of the head and neck of the radius, in certain fractures of the distal humerus, and also in irreducible dislocations and certain fracture-dislocations of the elbow.The incision is made along the line connecting the lateral epicondyle of the humerus and the border between the proximal and middle thirds of the ulna. The incision is pulled open and the strong, white opalescent common extensor fascia incised in order to identify the interval between the extensor carpi ulnaris and the anconeus. The two muscles are separated by thin vascularized fatty connective tissue which is split in order to expose a typical tendon reinforcing the upper half of the anterior margin of the anconeus. In this phase it is beneficial to detach the origin of the extensor carpi ulnaris from the lateral epicondyle. It facilitates retraction of the extensor carpi ulnaris anteriorly and of the anconeus slightly posteriorly. In contrast with the original Kocher approach, we do not release the anconeus from the lateral epicondyle of the humerus.The muscles are retracted to expose the anterolateral surface of the joint

  8. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  9. Muscle strain treatment

    Science.gov (United States)

    Treatment - muscle strain ... Question: How do you treat a muscle strain ? Answer: Rest the strained muscle and apply ice for the first few days after the injury. Anti-inflammatory medicines or acetaminophen ( ...

  10. Muscle Weakness

    Science.gov (United States)

    Al Kaissi, Ali; Ryabykh, Sergey; Ochirova, Polina; Kenis, Vladimir; Hofstätter, Jochen G.; Grill, Franz; Ganger, Rudolf; Kircher, Susanne Gerit

    2017-01-01

    Marked ligamentous hyperlaxity and muscle weakness/wasting associated with awkward gait are the main deficits confused with the diagnosis of myopathy. Seven children (6 boys and 1 girl with an average age of 8 years) were referred to our department because of diverse forms of skeletal abnormalities. No definitive diagnosis was made, and all underwent a series of sophisticated investigations in other institutes in favor of myopathy. We applied our methodology through the clinical and radiographic phenotypes followed by targeted genotypic confirmation. Three children (2 boys and 1 girl) were compatible with the diagnosis of progressive pseudorheumatoid chondrodysplasia. The genetic mutation was correlated with the WISP 3 gene actively expressed by articular chondrocytes and located on chromosome 6. Klinefelter syndrome was the diagnosis in 2 boys. Karyotyping confirmed 47,XXY (aneuploidy of Klinefelter syndrome). And 2 boys were finally diagnosed with Morquio syndrome (MPS type IV A) as both showed missense mutations in the N-acetylgalactosamine-sulfate sulfatase gene. Misdiagnosis can lead to the initiation of a long list of sophisticated investigations. PMID:28210640

  11. Reconditioning aging muscles.

    Science.gov (United States)

    Kraus, H

    1978-06-01

    Weakness or stiffness of key posture muscles can cause much of the disability seen in elderly patients. Too much tension and too little exercise greatly increase the natural loss of muscular fitness with age. A systematic program of exercise, stressing relaxation and stretching of tight muscles and strenghthening of weak muscles, can improve physical fitness. The program must be tailored to the patient, starting with relaxation and gentle limbering exercises and proceeding ultimately to vigorous muscle-stretching exercises. Muscle aches and pain from tension and muscle imbalance are to be expected. Relaxation relieves tension pain, and strengthening weak muscles and stretching tight muscles will correct muscle imbalance. To prevent acute muscle spasm, the patient should avoid excessive exertion and increase exercise intensity gradually.

  12. Short-Term Plasticity in a Monosynaptic Reflex Pathway to Forearm Muscles after Continuous Robot-Assisted Passive Stepping.

    Science.gov (United States)

    Nakajima, Tsuyoshi; Kamibayashi, Kiyotaka; Kitamura, Taku; Komiyama, Tomoyoshi; Zehr, E Paul; Nakazawa, Kimitaka

    2016-01-01

    Both active and passive rhythmic limb movements reduce the amplitude of spinal cord Hoffmann (H-) reflexes in muscles of moving and distant limbs. This could have clinical utility in remote modulation of the pathologically hyperactive reflexes found in spasticity after stroke or spinal cord injury. However, such clinical translation is currently hampered by a lack of critical information regarding the minimum or effective duration of passive movement needed for modulating spinal cord excitability. We therefore investigated the H-reflex modulation in the flexor carpi radialis (FCR) muscle during and after various durations (5, 10, 15, and 30 min) of passive stepping in 11 neurologically normal subjects. Passive stepping was performed by a robotic gait trainer system (Lokomat(®)) while a single pulse of electrical stimulation to the median nerve elicited H-reflexes in the FCR. The amplitude of the FCR H-reflex was significantly suppressed during passive stepping. Although 30 min of passive stepping was sufficient to elicit a persistent H-reflex suppression that lasted up to 15 min, 5 min of passive stepping was not. The duration of H-reflex suppression correlated with that of the stepping. These findings suggest that the accumulation of stepping-related afferent feedback from the leg plays a role in generating short-term interlimb plasticity in the circuitry of the FCR H-reflex.

  13. Short-term plasticity in a monosynaptic reflex pathway to forearm muscles after continuous robot-assisted passive stepping

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Nakajima

    2016-07-01

    Full Text Available Both active and passive rhythmic limb movements reduce the amplitude of spinal cord Hoffmann (H- reflexes in muscles of moving and distant limbs. This could have clinical utility in remote modulation of the pathologically hyperactive reflexes found in spasticity after stroke or spinal cord injury. However, such clinical translation is currently hampered by a lack of critical information regarding the minimum or effective duration of passive movement needed for modulating spinal cord excitability. We therefore investigated the H-reflex modulation in the flexor carpi radialis (FCR muscle during and after various durations (5, 10, 15, and 30 min of passive stepping in 11 neurologically normal subjects. Passive stepping was performed by a robotic gait trainer system (Lokomat® while a single pulse of electrical stimulation to the median nerve elicited H-reflexes in the FCR. The amplitude of the FCR H-reflex was significantly suppressed during passive stepping. Although 30 minutes of passive stepping was sufficient to elicit a persistent H-reflex suppression that lasted up to 15 minutes, 5 minutes of passive stepping was not. The duration of H-reflex suppression correlated with that of the stepping. These findings suggest that the accumulation of stepping-related afferent feedback from the leg plays a role in generating short-term interlimb plasticity in the circuitry of the FCR H-reflex.

  14. Motor cortical plasticity in extrinsic hand muscles is determined by the resting thresholds of overlapping representations.

    Science.gov (United States)

    Mirdamadi, J L; Suzuki, L Y; Meehan, S K

    2016-10-01

    Knowledge of the properties that govern the effectiveness of transcranial magnetic stimulation (TMS) interventions is critical to clinical application. Extrapolation to clinical populations has been limited by high inter-subject variability and a focus on intrinsic muscles of the hand in healthy populations. Therefore, the current study assessed variability of continuous theta burst stimulation (cTBS), a patterned TMS protocol, across an agonist-antagonist pair of extrinsic muscles of the hand. Secondarily, we assessed whether concurrent agonist contraction could enhance the efficacy of cTBS. Motor evoked potentials (MEP) were simultaneously recorded from the agonist flexor (FCR) and antagonist extensor (ECR) carpi radialis before and after cTBS over the FCR hotspot. cTBS was delivered with the FCR relaxed (cTBS-Relax) or during isometric wrist flexion (cTBS-Contract). cTBS-Relax suppressed FCR MEPs evoked from the FCR hotspot. However, the extent of FCR MEP suppression was strongly correlated with the relative difference between FCR and ECR resting motor thresholds. cTBS-Contract decreased FCR suppression but increased suppression of ECR MEPs elicited from the FCR hotspot. The magnitude of ECR MEP suppression following cTBS-Contract was independent of the threshold-amplitude relationships observed with cTBS-Relax. Contraction alone had no effect confirming the effect of cTBS-Contract was driven by the interaction between neuromuscular activity and cTBS. Interactions across muscle representations should be taken into account when predicting cTBS outcomes in healthy and clinical populations. Contraction during cTBS may be a useful means of focusing aftereffects when differences in baseline excitability across overlapping agonist-antagonist cortical representations may mitigate the inhibitory effect of cTBS.

  15. Hormonal and neuromuscular responses to mechanical vibration applied to upper extremity muscles.

    Directory of Open Access Journals (Sweden)

    Riccardo Di Giminiani

    Full Text Available OBJECTIVE: To investigate the acute residual hormonal and neuromuscular responses exhibited following a single session of mechanical vibration applied to the upper extremities among different acceleration loads. METHODS: Thirty male students were randomly assigned to a high vibration group (HVG, a low vibration group (LVG, or a control group (CG. A randomized double-blind, controlled-parallel study design was employed. The measurements and interventions were performed at the Laboratory of Biomechanics of the University of L'Aquila. The HVG and LVG participants were exposed to a series of 20 trials ×10 s of synchronous whole-body vibration (WBV with a 10-s pause between each trial and a 4-min pause after the first 10 trials. The CG participants assumed an isometric push-up position without WBV. The outcome measures were growth hormone (GH, testosterone, maximal voluntary isometric contraction during bench-press, maximal voluntary isometric contraction during handgrip, and electromyography root-mean-square (EMGrms muscle activity (pectoralis major [PM], triceps brachii [TB], anterior deltoid [DE], and flexor carpi radialis [FCR]. RESULTS: The GH increased significantly over time only in the HVG (P = 0.003. Additionally, the testosterone levels changed significantly over time in the LVG (P = 0.011 and the HVG (P = 0.001. MVC during bench press decreased significantly in the LVG (P = 0.001 and the HVG (P = 0.002. In the HVG, the EMGrms decreased significantly in the TB (P = 0.006 muscle. In the LVG, the EMGrms decreased significantly in the DE (P = 0.009 and FCR (P = 0.006 muscles. CONCLUSION: Synchronous WBV acutely increased GH and testosterone serum concentrations and decreased the MVC and their respective maximal EMGrms activities, which indicated a possible central fatigue effect. Interestingly, only the GH response was dependent on the acceleration with respect to the subjects' responsiveness.

  16. Effects of a novel forced intensive strengthening technique on muscle size and upper extremity function in a patient with chronic stroke.

    Science.gov (United States)

    Jeong, Hee-Won; Chon, Seung-Chul

    2015-11-01

    [Purpose] This research demonstrated a forced intensive strength technique as a novel treatment for muscle power and function in the affected upper extremity muscle to determine the clinical feasibility with respect to upper extremity performance in a stroke hemiparesis. [Subject and Methods] The subject was a patient with chronic stroke who was dependent on others for performing the functional activities of his affected upper extremity. The technique incorporates a comprehensive approach of forced, intensive, and strength-inducing activities to enhance morphological changes associated with motor learning of the upper extremity. The forced intensive strength technique consisted of a 6-week course of sessions lasting 60 minutes per day, five times a week. [Results] After the 6-week intervention, the difference between relaxation and contraction of the affected extensor carpi radialis muscle increased from 0.28 to 0.63 cm(2), and that of the affected triceps brachii muscle increased from 0.30 to 0.90 cm(2). The results of clinical tests including the modified Ashworth scale (MAS; from 1+ to 1), muscle strength (from 15 to 32 kg), the manual function test (MFT; scores of 16/32 to 27/32 score), the Fugl-Meyer assessment (FMA; scores of 29/66 to 49/66 score), and the Jebsen-Taylor hand function test (JTHFT; from 38/60 to 19/60 sec) were improved. [Conclusion] Our results suggest that the forced intensive strength technique may have a beneficial effect on the muscle size of the upper extremity and motor function in patients with chronic stroke.

  17. Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-Inspired Robotic Hand for Prosthetic Applications.

    Science.gov (United States)

    Fani, Simone; Bianchi, Matteo; Jain, Sonal; Pimenta Neto, José Simões; Boege, Scott; Grioli, Giorgio; Bicchi, Antonio; Santello, Marco

    2016-01-01

    Myoelectric artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human likeness of prosthesis movements, a goal which is being pursued by research on social and human-robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed so as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an underactuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e., flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography-to-position mapping ensured the

  18. Muscle strain injuries.

    Science.gov (United States)

    Garrett, W E

    1996-01-01

    One of the most common injuries seen in the office of the practicing physician is the muscle strain. Until recently, little data were available on the basic science and clinical application of this basic science for the treatment and prevention of muscle strains. Studies in the last 10 years represent action taken on the direction of investigation into muscle strain injuries from the laboratory and clinical fronts. Findings from the laboratory indicate that certain muscles are susceptible to strain injury (muscles that cross multiple joints or have complex architecture). These muscles have a strain threshold for both passive and active injury. Strain injury is not the result of muscle contraction alone, rather, strains are the result of excessive stretch or stretch while the muscle is being activated. When the muscle tears, the damage is localized very near the muscle-tendon junction. After injury, the muscle is weaker and at risk for further injury. The force output of the muscle returns over the following days as the muscle undertakes a predictable progression toward tissue healing. Current imaging studies have been used clinically to document the site of injury to the muscle-tendon junction. The commonly injured muscles have been described and include the hamstring, the rectus femoris, gastrocnemius, and adductor longus muscles. Injuries inconsistent with involvement of a single muscle-tendon junction proved to be at tendinous origins rather than within the muscle belly. Important information has also been provided regarding injuries with poor prognosis, which are potentially repairable surgically, including injuries to the rectus femoris muscle, the hamstring origin, and the abdominal wall. Data important to the management of common muscle injuries have been published. The risks of reinjury have been documented. The early efficacy and potential for long-term risks of nonsteroidal antiinflammatory agents have been shown. New data can also be applied to the field

  19. The anatomy and ontogeny of the head, neck, pectoral, and upper limb muscles of Lemur catta and Propithecus coquereli (primates): discussion on the parallelism between ontogeny and phylogeny and implications for evolutionary and developmental biology.

    Science.gov (United States)

    Diogo, Rui; Molnar, Julia L; Smith, Timothy D

    2014-08-01

    Most anatomical studies of primates focus on skeletal tissues, but muscular anatomy can provide valuable information about phylogeny, functional specializations, and evolution. Herein, we present the first detailed description of the head, neck, pectoral, and upper limb muscles of the fetal lemuriforms Lemur catta (Lemuridae) and Propithecus coquereli (Indriidae). These two species belong to the suborder Strepsirrhini, which is often presumed to possess some plesiomorphic anatomical features within primates. We compare the muscular anatomy of the fetuses with that of infants and adults and discuss the evolutionary and developmental implications. The fetal anatomy reflects a phylogenetically more plesiomorphic condition in nine of the muscles we studied and a more derived condition in only two, supporting a parallel between ontogeny and phylogeny. The derived exceptions concern muscles with additional insertions in the fetus which are lost in adults of the same species, that is, flexor carpi radialis inserts on metacarpal III and levator claviculae inserts on the clavicle. Interestingly, these two muscles are involved in movements of the pectoral girdle and upper limb, which are mainly important for activities in later stages of life, such as locomotion and prey capture, rather than activities in fetal life. Accordingly, our findings suggest that some exceptions to the "ontogeny parallels phylogeny" rule are probably driven more by ontogenetic constraints than by adaptive plasticity.

  20. Obturator internus muscle strains

    Directory of Open Access Journals (Sweden)

    Caoimhe Byrne, MB BCh, BAO

    2017-03-01

    Full Text Available We report 2 cases of obturator internus muscle strains. The injuries occurred in young male athletes involved in kicking sports. Case 1 details an acute obturator internus muscle strain with associated adductor longus strain. Case 2 details an overuse injury of the bilateral obturator internus muscles. In each case, magnetic resonance imaging played a crucial role in accurate diagnosis.

  1. ANATOMICAL VARIATION OF PALMARIS LONGUS: TENDINOUS ORIGIN AND FLESHY INSERTION

    Directory of Open Access Journals (Sweden)

    Buddhadeb Ghosh

    2015-03-01

    Full Text Available A tendinous origin and fleshy insertion of palmaris longus muscle was observed in the left forearm during routine dissection which was performed on adult male cadaver in the department of Anatomy, Dr. Rajendra Prasad Government Medical College. It was having long tendinous origin from the medial epicondyle of the humerus and the surrounding deep fascia. It was fusiform at the lower middle of the forearm. The fleshy muscular insertion was noted to the flexor retinaculum and few muscular fibers interdigitate with flexor carpi ulnaris muscle and palmar aponeurosis. The length of tendon was 19 inches and fleshy muscular length was 11inches. The median nerve and ulnar nerve was covered by this fleshy insertion. This palmaris longus variation is helpful for the surgeon and the radiologist, orthopaedic, plastic surgeon during any diagnosis of the forearm because this fleshy part of muscle can compress the median nerve and ulnar nerve or it can be mistaken as a tumor or ganglion during radiological or clinical examination.

  2. Optical characterization of muscle

    Science.gov (United States)

    Oliveira, Luís; Lage, Armindo; Pais Clemente, Manuel; Tuchin, Valery V.

    2012-03-01

    Optical characterization and internal structure of biological tissues is highly important for biomedical optics. In particular for optical clearing processes, such information is of vital importance to understand the mechanisms involved through the variation of the refractive indices of tissue components. The skeletal muscle presents a fibrous structure with an internal arrangement of muscle fiber cords surrounded by interstitial fluid that is responsible for strong light scattering. To determine the refractive index of muscle components we have used a simple method of measuring tissue mass and refractive index during dehydration. After performing measurements for natural and ten dehydration states of the muscle samples, we have determined the dependence between the refractive index of the muscle and its water content. Also, we have joined our measurements with some values reported in literature to perform some calculations that have permitted to determine the refractive index of the dried muscle fibers and their corresponding volume percentage inside the natural muscle.

  3. Stenosing tenosynovitis.

    Science.gov (United States)

    Vuillemin, V; Guerini, H; Bard, H; Morvan, G

    2012-02-01

    Tenosynovitis refers to an inflammatory condition involving the synovial sheath of a tendon. Stenosing tenosynovitis is a peculiar entity caused by multiple factors, including local anatomy, mechanical factors, and hormonal factors. The main forms include de Quervain tendinopathy; trigger finger (stenosing tenosynovitis involving the flexor digitorum tendons); stenosing tenosynovitis of the extensor carpi ulnaris, extensor carpi radialis, or extensor comunis tendons; stenosing tenosynovitis of the flexor hallucis tendon; and stenosing tenosynovitis of the peroneal tendons. The cardinal finding on ultrasonography is the presence of a thickened retinaculum or pulley that constricts the osseofibrous tunnel through which the tendon runs.

  4. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    Directory of Open Access Journals (Sweden)

    Matthew Emerson Randolph

    2015-10-01

    Full Text Available The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies, such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some muscular dystrophies. The biology of muscle stem cells varies depending on their embryologic origins and the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease.

  5. Muscle glycogenolysis during exercise

    DEFF Research Database (Denmark)

    Richter, Erik; Ruderman, N B; Gavras, H

    1982-01-01

    The interaction of epinephrine and contractions on muscle metabolism was studied in the isolated perfused rat hindquarter. Subtetanic contractions (180/min) through 20 min elicited glycogenolysis and increased phosphorylase a activity. In the soleus, a slow-twitch red muscle, these effects were...... transient, but when epinephrine at a physiological concentration (2.4 X 10(-8) M) was added to the perfusate, glycogenolysis and phosphorylase activity were sustained throughout contractions. At this high frequency of contractions, the effect of epinephrine was much smaller in the fast-twitch red fibers...... and not significant in the fast-twitch white fibers of the gastrocnemius muscle. However, during less frequent contractions (30/min) epinephrine increased glycogenolysis and phosphorylase a activity in fast-twitch muscle. The data suggest that epinephrine and muscle contractions exert a dual control of muscle...

  6. Proteomics of Skeletal Muscle

    DEFF Research Database (Denmark)

    Deshmukh, Atul

    2016-01-01

    Skeletal muscle is the largest tissue in the human body and plays an important role in locomotion and whole body metabolism. It accounts for ~80% of insulin stimulated glucose disposal. Skeletal muscle insulin resistance, a primary feature of Type 2 diabetes, is caused by a decreased ability...... of muscle to respond to circulating insulin. Physical exercise improves insulin sensitivity and whole body metabolism and remains one of the most promising interventions for the prevention of Type 2 diabetes. Insulin resistance and exercise adaptations in skeletal muscle might be a cause, or consequence...

  7. Accessory piriformis muscle

    Directory of Open Access Journals (Sweden)

    Sedat Develi

    2017-03-01

    Full Text Available Piriformis muscle originates from facies pelvica of sacrum and inserts on the trochanter major. It is one of the lateral rotator muscles of the hip and a landmark point in the gluteal region since n. ischiadicus descends to the thigh by passing close to the muscle. This contiguity may be associated with the irritation of the nerve which is known as piriformis syndrome. A rare anatomic variation of the muscle which observed on 74 years old male cadaver is discussed in this case report. [Cukurova Med J 2017; 42(1.000: 182-183

  8. MUSCLE INJURIES IN ATHLETES.

    Science.gov (United States)

    Barroso, Guilherme Campos; Thiele, Edilson Schwansee

    2011-01-01

    This article had the aim of demonstrating the physiology, diagnosis and treatment of muscle injuries, focusing on athletes and their demands and expectations. Muscle injuries are among the most common complaints in orthopedic practice, occurring both among athletes and among non-athletes. These injuries present a challenge for specialists, due to the slow recovery, during which time athletes are unable to take part in training and competitions, and due to frequent sequelae and recurrences of the injuries. Most muscle injuries (between 10% and 55% of all injuries) occur during sports activities. The muscles most commonly affected are the ischiotibial, quadriceps and gastrocnemius. These muscles go across two joints and are more subject to acceleration and deceleration forces. The treatment for muscle injuries varies from conservative treatment to surgery. New procedures are being used, like the hyperbaric chamber and the use of growth factors. However, there is still a high rate of injury recurrence. Muscle injury continues to be a topic of much controversy. New treatments are being researched and developed, but prevention through muscle strengthening, stretching exercises and muscle balance continues to be the best "treatment".

  9. Guyon tunnel syndrome secondary to excessive healing tissue in a child: a case report

    Directory of Open Access Journals (Sweden)

    Sevinç Teoman

    2008-05-01

    Full Text Available Abstract We describe a case of an 8-year-old boy who developed a combined motor and sensory neuropathy of the distal ulnar nerve, after sustaining a superficial injury to the right flexor carpi ulnaris tendon at the level of the distal wrist crease. Guyon's canal syndrome is a very rare entity during childhood. We have noted only one prior description of this syndrome in the pediatric age group in a review of the English literature.

  10. Skeletal muscle development and regeneration.

    NARCIS (Netherlands)

    Grefte, S.; Kuijpers-Jagtman, A.M.; Torensma, R.; Hoff, J.W. Von den

    2007-01-01

    In the late stages of muscle development, a unique cell population emerges that is a key player in postnatal muscle growth and muscle regeneration. The location of these cells next to the muscle fibers triggers their designation as satellite cells. During the healing of injured muscle tissue, satell

  11. Development of a Compact Wireless Laplacian Electrode Module for Electromyograms and Its Human Interface Applications

    Directory of Open Access Journals (Sweden)

    Akira Ichikawa

    2013-02-01

    Full Text Available In this study, we developed a compact wireless Laplacian electrode module for electromyograms (EMGs. One of the advantages of the Laplacian electrode configuration is that EMGs obtained with it are expected to be sensitive to the firing of the muscle directly beneath the measurement site. The performance of the developed electrode module was investigated in two human interface applications: character-input interface and detection of finger movement during finger Braille typing. In the former application, the electrode module was combined with an EMG-mouse click converter circuit. In the latter, four electrode modules were used for detection of finger movements during finger Braille typing. Investigation on the character-input interface indicated that characters could be input stably by contraction of (a the masseter, (b trapezius, (c anterior tibialis and (d flexor carpi ulnaris muscles. This wide applicability is desirable when the interface is applied to persons with physical disabilities because the disability differs one to another. The investigation also demonstrated that the electrode module can work properly without any skin preparation. Finger movement detection experiments showed that each finger movement was more clearly detectable when comparing to EMGs recorded with conventional electrodes, suggesting that the Laplacian electrode module is more suitable for detecting the timing of finger movement during typing. This could be because the Laplacian configuration enables us to record EMGs just beneath the electrode. These results demonstrate the advantages of the Laplacian electrode module.

  12. Use of quantitative intra-operative electrodiagnosis during partial ulnar nerve transfer to restore elbow flexion: the treatment of eight patients following a brachial plexus injury.

    Science.gov (United States)

    Suzuki, O; Sunagawa, T; Yokota, K; Nakashima, Y; Shinomiya, R; Nakanishi, K; Ochi, M

    2011-03-01

    The transfer of part of the ulnar nerve to the musculocutaneous nerve, first described by Oberlin, can restore flexion of the elbow following brachial plexus injury. In this study we evaluated the additional benefits and effectiveness of quantitative electrodiagnosis to select a donor fascicle. Eight patients who had undergone transfer of a simple fascicle of the ulnar nerve to the motor branch of the musculocutaneous nerve were evaluated. In two early patients electrodiagnosis had not been used. In the remaining six patients, however, all fascicles of the ulnar nerve were separated and electrodiagnosis was performed after stimulation with a commercially available electromyographic system. In these procedures, recording electrodes were placed in flexor carpi ulnaris and the first dorsal interosseous. A single fascicle in the flexor carpi ulnaris in which a high amplitude had been recorded was selected as a donor and transferred to the musculocutaneous nerve. In the two patients who had not undergone electrodiagnosis, the recovery of biceps proved insufficient for normal use. Conversely, in the six patients in whom quantitative electrodiagnosis was used, elbow flexion recovered to an M4 level. Quantitative intra-operative electrodiagnosis is an effective method of selecting a favourable donor fascicle during the Oberlin procedure. Moreover, fascicles showing a high-amplitude in reading flexor carpi ulnaris are donor nerves that can restore normal elbow flexion without intrinsic loss.

  13. Muscle phosphorylase kinase deficiency

    DEFF Research Database (Denmark)

    Preisler, N; Orngreen, M C; Echaniz-Laguna, A;

    2012-01-01

    To examine metabolism during exercise in 2 patients with muscle phosphorylase kinase (PHK) deficiency and to further define the phenotype of this rare glycogen storage disease (GSD).......To examine metabolism during exercise in 2 patients with muscle phosphorylase kinase (PHK) deficiency and to further define the phenotype of this rare glycogen storage disease (GSD)....

  14. Turning Marrow into Muscle

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ In unexpected testimony2 to the versatility3 of the body's cells,researchers have found they can make bone marrow cells turn into muscle, causing mice with muscular dystrophy4 to produce correctly working muscle cells. The experiment suggests that a form of bone marrow transplant- - a well established surgical procedure5- - could in principle treat patients with a variety of diseases.

  15. Muscles, exercise and obesity

    DEFF Research Database (Denmark)

    Pedersen, Bente K; Febbraio, Mark A

    2012-01-01

    During the past decade, skeletal muscle has been identified as a secretory organ. Accordingly, we have suggested that cytokines and other peptides that are produced, expressed and released by muscle fibres and exert either autocrine, paracrine or endocrine effects should be classified as myokines...

  16. Muscle contraction and force

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline; Risbo, Jens; Pierzynowski, Stefan G.

    2008-01-01

    Muscle contraction studies often focus solely on myofibres and the proteins known to be involved in the processes of sarcomere shortening and cross-bridge cycling, but skeletal muscle also comprises a very elaborate ancillary network of capillaries, which not only play a vital role in terms...... contributor to force transfer within muscular tissue....

  17. Onion artificial muscles

    Science.gov (United States)

    Chen, Chien-Chun; Shih, Wen-Pin; Chang, Pei-Zen; Lai, Hsi-Mei; Chang, Shing-Yun; Huang, Pin-Chun; Jeng, Huai-An

    2015-05-01

    Artificial muscles are soft actuators with the capability of either bending or contraction/elongation subjected to external stimulation. However, there are currently no artificial muscles that can accomplish these actions simultaneously. We found that the single layered, latticed microstructure of onion epidermal cells after acid treatment became elastic and could simultaneously stretch and bend when an electric field was applied. By modulating the magnitude of the voltage, the artificial muscle made of onion epidermal cells would deflect in opposing directions while either contracting or elongating. At voltages of 0-50 V, the artificial muscle elongated and had a maximum deflection of -30 μm; at voltages of 50-1000 V, the artificial muscle contracted and deflected 1.0 mm. The maximum force response is 20 μN at 1000 V.

  18. Muscle as a secretory organ

    DEFF Research Database (Denmark)

    Pedersen, Bente K

    2013-01-01

    Skeletal muscle is the largest organ in the body. Skeletal muscles are primarily characterized by their mechanical activity required for posture, movement, and breathing, which depends on muscle fiber contractions. However, skeletal muscle is not just a component in our locomotor system. Recent...... proteins produced by skeletal muscle are dependent upon contraction. Therefore, it is likely that myokines may contribute in the mediation of the health benefits of exercise....... evidence has identified skeletal muscle as a secretory organ. We have suggested that cytokines and other peptides that are produced, expressed, and released by muscle fibers and exert either autocrine, paracrine, or endocrine effects should be classified as "myokines." The muscle secretome consists...

  19. A muscle model for hybrid muscle activation

    Directory of Open Access Journals (Sweden)

    Klauer Christian

    2015-09-01

    Full Text Available To develop model-based control strategies for Functional Electrical Stimulation (FES in order to support weak voluntary muscle contractions, a hybrid model for describing joint motions induced by concurrent voluntary-and FES induced muscle activation is proposed. It is based on a Hammerstein model – as commonly used in feedback controlled FES – and exemplarily applied to describe the shoulder abduction joint angle. Main component of a Hammerstein muscle model is usually a static input nonlinearity depending on the stimulation intensity. To additionally incorporate voluntary contributions, we extended the static non-linearity by a second input describing the intensity of the voluntary contribution that is estimated by electromyography (EMG measurements – even during active FES. An Artificial Neural Network (ANN is used to describe the static input non-linearity. The output of the ANN drives a second-order linear dynamical system that describes the combined muscle activation and joint angle dynamics. The tunable parameters are adapted to the individual subject by a system identification approach using previously recorded I/O-data. The model has been validated in two healthy subjects yielding RMS values for the joint angle error of 3.56° and 3.44°, respectively.

  20. Polymer artificial muscles

    Directory of Open Access Journals (Sweden)

    Tissaphern Mirfakhrai

    2007-04-01

    Full Text Available The various types of natural muscle are incredible material systems that enable the production of large deformations by repetitive molecular motions. Polymer artificial muscle technologies are being developed that produce similar strains and higher stresses using electrostatic forces, electrostriction, ion insertion, and molecular conformational changes. Materials used include elastomers, conducting polymers, ionically conducting polymers, and carbon nanotubes. The mechanisms, performance, and remaining challenges associated with these technologies are described. Initial applications are being developed, but further work by the materials community should help make these technologies applicable in a wide range of devices where muscle-like motion is desirable.

  1. Painful unilateral temporalis muscle enlargement: reactive masticatory muscle hypertrophy.

    Science.gov (United States)

    Katsetos, Christos D; Bianchi, Michael A; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2014-06-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptomatic improvement only after undergoing botulinum toxin injections. Muscle biopsy is key in the diagnosis of reactive masticatory muscle hypertrophy and its distinction from masticatory muscle myopathy (hypertrophic branchial myopathy) and other non-reactive causes of painful asymmetric temporalis muscle enlargement.

  2. Construction features and application of a new wrist-hand orthosis%一种新型腕手矫形器的结构特点及其使用

    Institute of Scientific and Technical Information of China (English)

    冉春风

    2008-01-01

    AIM: To introduce a new kind of wrist-hand orthosis.METHODS: The major frame of wrist-hand orthosis is composed of dorsal carpal guard plate and carpal bracket; while, a U-shaped anterior bracket is fixed on the anterior side of the major frame. Ferrules of index finger, middle finger, fourth finger and little finger respectively connect to dorsal carpal guard plate of the major frame via elastic brace; ferrule of thumb is fixed on one side of ferrule of index finger by using steel wires; an abduct elastic sleeve is designed on the lateral dorsal carpal guard plate of ferrule of little finger by using steel wires. According to experimental demands, wrist with the palms upward or downward puts into the major frame, which is composed of dorsal carpal guard plate and carpal bracket. The hand is anterior to the major frame; ferrules are located over rolling sleeve by forward and fingers are located below the rolling sleeve by forward; ferrules are respectively rang the index, middle, fourth and little fingers; ferrule of thumb is rang the thumb. Continuously, wrist rotates based on orthopaedic demands to realize various orthopaedic functions.RESULTS: The wrist-hand orthosis is used to help the hand maintain extension after extensor tendon injury operation in order to restrict active areas of fingers and promote healing of injured side. On the other hand, this new orthosis is also used to help wrist joint and digital joint maintain flexion after extensor tendon injury operation in order to improve flexion and extension of wrist joint, enlarge active area of flexion of wrist joint, enlarge drifting active area of radialis of wrist joint, and increase muscle strength of radial flexor muscle, ulnar flexor muscle, extensor carpi radialis muscle, extensor carpi ulnaris muscle, extensor carpi ulnaris muscle, flexor carpi ulnaris muscle, extensor digitorum communis muscle, superficial flexor muscle and deep flexor muscle.CONCLUSION: The wrist-hand orthosis refers to protection

  3. Muscle Cramp - A Common Pain

    Science.gov (United States)

    ... Osteopathic Manipulative Treatment Becoming a DO Video Library Muscle Cramp – A Common Pain Page Content Has a muscle ... body’s natural tendency toward self-healing. Causes of Muscle Cramps Muscle cramps can occur anywhere, anytime to anyone. “ ...

  4. Muscles and their myokines

    DEFF Research Database (Denmark)

    Pedersen, Bente Klarlund

    2011-01-01

    In the past, the role of physical activity as a life-style modulating factor has been considered as that of a tool to balance energy intake. Although it is important to avoid obesity, physical inactivity should be discussed in a much broader context. There is accumulating epidemiological evidence...... or endocrine effects should be classified as 'myokines'. Given that skeletal muscle is the largest organ in the human body, our discovery that contracting skeletal muscle secretes proteins sets a novel paradigm: skeletal muscle is an endocrine organ producing and releasing myokines, which work in a hormone...... that a physically active life plays an independent role in the protection against type 2 diabetes, cardiovascular diseases, cancer, dementia and even depression. For most of the last century, researchers sought a link between muscle contraction and humoral changes in the form of an 'exercise factor', which could...

  5. Healthy Muscles Matter

    Science.gov (United States)

    ... To help prevent sprains, strains, and other muscle injuries: Warm up and cool down . Before exercising or playing sports, warm-up exercises, such as stretching and light jogging, may make it less likely ...

  6. Muscle biopsy (image)

    Science.gov (United States)

    A muscle biopsy involves removal of a plug of tissue usually by a needle to be later used for examination. Sometimes ... there is a patchy condition expected an open biopsy may be used. Open biopsy involves a small ...

  7. Neurogenic muscle cramps.

    Science.gov (United States)

    Katzberg, Hans D

    2015-08-01

    Muscle cramps are sustained, painful contractions of muscle and are prevalent in patients with and without medical conditions. The objective of this review is to present updates on the mechanism, investigation and treatment of neurogenic muscle cramps. PubMed and Embase databases were queried between January 1980 and July 2014 for English-language human studies. The American Academy of Neurology classification of studies (classes I-IV) was used to assess levels of evidence. Mechanical disruption, ephaptic transmission, disruption of sensory afferents and persistent inward currents have been implicated in the pathogenesis of neurogenic cramps. Investigations are directed toward identifying physiological triggers or medical conditions predisposing to cramps. Although cramps can be self-limiting, disabling or sustained muscle cramps should prompt investigation for underlying medical conditions. Lifestyle modifications, treatment of underlying conditions, stretching, B-complex vitamins, diltiezam, mexiletine, carbamazepine, tetrahydrocannabinoid, leveteracitam and quinine sulfate have shown evidence for treatment.

  8. Muscle as a secretory organ.

    Science.gov (United States)

    Pedersen, Bente K

    2013-07-01

    Skeletal muscle is the largest organ in the body. Skeletal muscles are primarily characterized by their mechanical activity required for posture, movement, and breathing, which depends on muscle fiber contractions. However, skeletal muscle is not just a component in our locomotor system. Recent evidence has identified skeletal muscle as a secretory organ. We have suggested that cytokines and other peptides that are produced, expressed, and released by muscle fibers and exert either autocrine, paracrine, or endocrine effects should be classified as "myokines." The muscle secretome consists of several hundred secreted peptides. This finding provides a conceptual basis and a whole new paradigm for understanding how muscles communicate with other organs such as adipose tissue, liver, pancreas, bones, and brain. In addition, several myokines exert their effects within the muscle itself. Many proteins produced by skeletal muscle are dependent upon contraction. Therefore, it is likely that myokines may contribute in the mediation of the health benefits of exercise.

  9. A higher number of TMS-elicited MEP from a combined hotspot improves intra- and inter-session reliability of the upper limb muscles in healthy individuals.

    Science.gov (United States)

    Bastani, Andisheh; Jaberzadeh, Shapour

    2012-01-01

    We aimed to determine, using transcranial magnetic stimulation (TMS), the number of elicited motor evoked potentials (MEPs) that induces the highest intra- and inter-sessions reliability for the extensor carpi radialis (ECR) and first dorsal interosseus (FDI) muscles. Twelve healthy subjects participated in this study on two separate days. Single pulse magnetic stimuli were triggered with Magstim 200(2) to obtain MEPs from the muscles of interest, with the subjects in a relaxed position. Reliability of MEP responses was investigated in three blocks of 5, 10 and 15 trials. The intra- and inter-session reliability of the MEPs' amplitudes and latencies were assessed using intraclass correlation coefficients (ICCs). Repeated measures ANOVA and paired t-tests revealed no significant time effect in the MEP amplitude and latency measurements (P>0.05). The ICCs indicated high intra-session reliability in the MEPs' amplitudes for the ECR and FDI muscles (0.77 to 0.99, 0.90 to 0.99, respectively) and latency (0.80 to 1.00, 0.75 to 0.97, respectively). The MEPs' amplitudes also had high inter-session reliability (0.84 to 0.97, 0.88 to 0.93, respectively), as did their latency (0.80 to 0.90, 0.75 to 0.97, respectively). Highest intra- and inter-session reliability was achieved for blocks of 10 and 15 trials. Our data suggest that intra- and inter-session comparisons should be performed using at least 10 MEPs in "combined hotspot" stimulation technique to ensure highest reliability.

  10. A higher number of TMS-elicited MEP from a combined hotspot improves intra- and inter-session reliability of the upper limb muscles in healthy individuals.

    Directory of Open Access Journals (Sweden)

    Andisheh Bastani

    Full Text Available We aimed to determine, using transcranial magnetic stimulation (TMS, the number of elicited motor evoked potentials (MEPs that induces the highest intra- and inter-sessions reliability for the extensor carpi radialis (ECR and first dorsal interosseus (FDI muscles. Twelve healthy subjects participated in this study on two separate days. Single pulse magnetic stimuli were triggered with Magstim 200(2 to obtain MEPs from the muscles of interest, with the subjects in a relaxed position. Reliability of MEP responses was investigated in three blocks of 5, 10 and 15 trials. The intra- and inter-session reliability of the MEPs' amplitudes and latencies were assessed using intraclass correlation coefficients (ICCs. Repeated measures ANOVA and paired t-tests revealed no significant time effect in the MEP amplitude and latency measurements (P>0.05. The ICCs indicated high intra-session reliability in the MEPs' amplitudes for the ECR and FDI muscles (0.77 to 0.99, 0.90 to 0.99, respectively and latency (0.80 to 1.00, 0.75 to 0.97, respectively. The MEPs' amplitudes also had high inter-session reliability (0.84 to 0.97, 0.88 to 0.93, respectively, as did their latency (0.80 to 0.90, 0.75 to 0.97, respectively. Highest intra- and inter-session reliability was achieved for blocks of 10 and 15 trials. Our data suggest that intra- and inter-session comparisons should be performed using at least 10 MEPs in "combined hotspot" stimulation technique to ensure highest reliability.

  11. Changes in T2-weighted MRI of supinator muscle, pronator teres muscle, and extensor indicis muscle with manual muscle testing

    Science.gov (United States)

    Yoshida, Kazuya; Akiyama, Sumikazu; Takamori, Masayoshi; Otsuka, D. Eng, Hiroshi; Seo, Yoshiteru

    2017-01-01

    [Purpose] In order to detect muscle activity with manual muscle testing, T2-weighted magnetic resonance (T2w-MR) images were detected by a 0.2 T compact MRI system. [Subjects and Methods] The subjects were 3 adult males. Transverse T2-weighted multi-slice spin-echo images of the left forearm were measured by a 39 ms echo-time with a 2,000 ms repetition time, a 9.5 mm slice thickness, 1 accumulation and a total image acquisition time of 4 min 16 s. First, T2w-MR images in the resting condition were measured. Then, manipulative isometric contraction exercise (5 sec duration) to the supinator muscle, the pronator teres muscle or the extensor indicis muscle was performed using Borg’s rating of perceived exertion (RPE) scale of 15–17. The T2w-MR images were measured immediately after the exercise. [Results] T2w-MR image intensities increased significantly in the supinator muscle, the pronator teres muscle and the extensor indicis muscle after the exercise. However, the image intensities in the rest of the muscle did not change. [Conclusion] Using T2w-MR images, we could detect muscle activity in a deep muscle, the supinator muscle, and a small muscle, the extensor indicis muscle. These results also support the reliability of the manual muscle testing method. PMID:28356621

  12. Guyon's tunnel syndrome during pregnancy with concomitant anomalous arch of the ulnar nerve: a case report.

    Science.gov (United States)

    Janmohammadi, Nasser

    2014-01-01

    Numerous causes are reported for ulnar nerve compression at the wrist, known as Guyon's tunnel syndrome. In the present article, a patient with Guyon's tunnel syndrome during pregnancy concomitant with an anomaly of ulnar nerve is described. A 29-year-old Iranian woman presented with clinical features of Guyon's tunnel syndrome (pain and paresthesia in the fifth finger of the left hand and atrophy of the first dorsal interosseus muscle). Symptoms of the patient appeared during the third trimester of pregnancy. Electro diagnostic studies confirmed Guyon's tunnel syndrome. Surgical exploration revealed an anomalous arch of the ulnar nerve passing through the flexor carpi ulnaris (FCU) tendon. The anomalous arch of the ulnar nerve was released by resection of the segment of FCU tendon passing through the ulnar nerve arch. Therefore, in patients with Guyon's tunnel syndrome, the ulnar nerve anomaly should be kept in mind as a cause. Moreover, pregnancy may have a provocative effect on Guyon's tunnel syndrome similar to carpal tunnel syndrome (CTS).

  13. Guyon's tunnel syndrome during pregnancy with concomitant anomalous arch of the ulnar nerve: a case report.

    Directory of Open Access Journals (Sweden)

    Nasser Janmohammadi

    2014-07-01

    Full Text Available Numerous causes are reported for ulnar nerve compression at the wrist, known as Guyon's tunnel syndrome. In the present article, a patient with Guyon's tunnel syndrome during pregnancy concomitant with an anomaly of ulnar nerve is described. A 29-year-old Iranian woman presented with clinical features of Guyon's tunnel syndrome (pain and paresthesia in the fifth finger of the left hand and atrophy of the first dorsal interosseus muscle. Symptoms of the patient appeared during the third trimester of pregnancy. Electro diagnostic studies confirmed Guyon's tunnel syndrome. Surgical exploration revealed an anomalous arch of the ulnar nerve passing through the flexor carpi ulnaris (FCU tendon. The anomalous arch of the ulnar nerve was released by resection of the segment of FCU tendon passing through the ulnar nerve arch. Therefore, in patients with Guyon's tunnel syndrome, the ulnar nerve anomaly should be kept in mind as a cause. Moreover, pregnancy may have a provocative effect on Guyon's tunnel syndrome similar to carpal tunnel syndrome (CTS.

  14. A Beetle Flight Muscle Displays Leg Muscle Microstructure.

    Science.gov (United States)

    Shimomura, Toshiki; Iwamoto, Hiroyuki; Vo Doan, Tat Thang; Ishiwata, Shin'ichi; Sato, Hirotaka; Suzuki, Madoka

    2016-09-20

    In contrast to major flight muscles in the Mecynorrhina torquata beetle, the third axillary (3Ax) muscle is a minor flight muscle that uniquely displays a powerful mechanical function despite its considerably small volume, ∼1/50 that of a major flight muscle. The 3Ax muscle contracts relatively slowly, and in flight strongly pulls the beating wing to attenuate the stroke amplitude. This attenuation leads to left-right turning in flight or wing folding to cease flying. What enables this small muscle to be so powerful? To explore this question, we examined the microstructure of the 3Ax muscle using synchrotron x-ray diffraction, optical microscopy, and immunoblotting analysis. We found that the 3Ax muscle has long (∼5 μm) myofilaments and that the ratio of thick (myosin) filaments to thin (actin) filaments is 1:5 or 1:6. These characteristics are not observed in the major flight muscles, which have shorter myofilaments (∼3.5 μm) with a smaller ratio (1:3), and instead are more typical of a leg muscle. Furthermore, the flight-muscle-specific troponin isoform, TnH, is not expressed in the 3Ax muscle. Since such a microstructure is suitable for generating large tension, the 3Ax muscle is appropriately designed to pull the wing strongly despite its small volume.

  15. Foot muscles strengthener

    Directory of Open Access Journals (Sweden)

    Boris T. Glavač

    2012-04-01

    Full Text Available Previous experience in the correction of flat feet consisted of the use of insoles for shoes and exercises with toys, balls, rollers, inclined planes, etc. A device for strengthening foot muscles is designed for the correction of flat feet in children and, as its name suggests, for strengthening foot muscles in adults. The device is made of wood and metal, with a mechanism and technical solutions, enabling the implementation of specific exercises to activate muscles responsible for the formation of the foot arch. It is suitable for home use with controlled load quantities since it has calibrated springs. The device is patented with the Intellectual Property Office, Republic of Serbia, as a petty patent.

  16. Artificial muscles on heat

    Science.gov (United States)

    McKay, Thomas G.; Shin, Dong Ki; Percy, Steven; Knight, Chris; McGarry, Scott; Anderson, Iain A.

    2014-03-01

    Many devices and processes produce low grade waste heat. Some of these include combustion engines, electrical circuits, biological processes and industrial processes. To harvest this heat energy thermoelectric devices, using the Seebeck effect, are commonly used. However, these devices have limitations in efficiency, and usable voltage. This paper investigates the viability of a Stirling engine coupled to an artificial muscle energy harvester to efficiently convert heat energy into electrical energy. The results present the testing of the prototype generator which produced 200 μW when operating at 75°C. Pathways for improved performance are discussed which include optimising the electronic control of the artificial muscle, adjusting the mechanical properties of the artificial muscle to work optimally with the remainder of the system, good sealing, and tuning the resonance of the displacer to minimise the power required to drive it.

  17. Signaling in muscle contraction.

    Science.gov (United States)

    Kuo, Ivana Y; Ehrlich, Barbara E

    2015-02-02

    Signaling pathways regulate contraction of striated (skeletal and cardiac) and smooth muscle. Although these are similar, there are striking differences in the pathways that can be attributed to the distinct functional roles of the different muscle types. Muscles contract in response to depolarization, activation of G-protein-coupled receptors and other stimuli. The actomyosin fibers responsible for contraction require an increase in the cytosolic levels of calcium, which signaling pathways induce by promoting influx from extracellular sources or release from intracellular stores. Rises in cytosolic calcium stimulate numerous downstream calcium-dependent signaling pathways, which can also regulate contraction. Alterations to the signaling pathways that initiate and sustain contraction and relaxation occur as a consequence of exercise and pathophysiological conditions.

  18. Changes of muscle induced with injection of botulinum toxin type A in different period of time%A型肉毒毒素肌内注射后不同时间段肌肉改变的观察

    Institute of Scientific and Technical Information of China (English)

    汪灏; 李森恺; 杨明勇; 李养群; 李强; 王伊宁; 鲍世威

    2012-01-01

    Objective To study the changes of muscle being injected with botulinum toxin A in different period of time,helping for chemically denervated muscle transplantation.Methods Sixteen rabbits were divided into 4 groups.The extensor carpi radialis muscle in one side was chosen for experimental group with the opposite muscle for control group.Morphological changes,histological changes and electron microscopic changes of muscle being injected with botulinum toxin A were observed from the first week to the fouth week.Results The quantity of glycogen and mitochondria in the muscles reduced in the first week.But it was obvious in the third week.We also found some necrotic areas in the fouth week with the muscles restoring.Conclusions The effect of metabolism slowing down and the volume of muscle reducing after botulinum toxin A injection is obvious in third weeks.It could help us choose the best time of chemically denervated muscle transplantation.%目的 通过对A型肉毒毒素肌内注射后不同时间段肌肉的改变进行观察,了解肉毒毒素对肌肉的改变过程,并为化学去神经肌肉游离移植提供理论依据.方法 对16只活体兔桡侧腕伸肌进行肉毒毒素注射,分为4组(即1、2、3、4周组),每组4个肌肉,躯体对侧作为对比.分别在注射后1~4周进行大体观察,以及组织学和电镜观察.结果 药物注射后1周,肌内酶、糖原和线粒体都开始减少,体积的减少在3周左右明显,4周后肌酶的减少更加明显,并且内部区域有坏死灶,但体积较前有所恢复.结论 A型肉毒毒素肌内注射后可以减缓肌肉代谢和缩小肌肉体积,其中以第3周最为明显,可以为化学去神经肌肉游离移植的时间选择提供参考.

  19. Composition of Muscle Fiber Types in Rat Rotator Cuff Muscles.

    Science.gov (United States)

    Rui, Yongjun; Pan, Feng; Mi, Jingyi

    2016-10-01

    The rat is a suitable model to study human rotator cuff pathology owing to the similarities in morphological anatomy structure. However, few studies have reported the composition muscle fiber types of rotator cuff muscles in the rat. In this study, the myosin heavy chain (MyHC) isoforms were stained by immunofluorescence to show the muscle fiber types composition and distribution in rotator cuff muscles of the rat. It was found that rotator cuff muscles in the rat were of mixed fiber type composition. The majority of rotator cuff fibers labeled positively for MyHCII. Moreover, the rat rotator cuff muscles contained hybrid fibers. So, compared with human rotator cuff muscles composed partly of slow-twitch fibers, the majority of fast-twitch fibers in rat rotator cuff muscles should be considered when the rat model study focus on the pathological process of rotator cuff muscles after injury. Gaining greater insight into muscle fiber types in rotator cuff muscles of the rat may contribute to elucidate the mechanism of pathological change in rotator cuff muscles-related diseases. Anat Rec, 299:1397-1401, 2016. © 2016 Wiley Periodicals, Inc.

  20. Pelvic floor muscle training exercises

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003975.htm Pelvic floor muscle training exercises To use the sharing features on this page, please enable JavaScript. Pelvic floor muscle training exercises are a series of exercises ...

  1. Active vs. inactive muscle (image)

    Science.gov (United States)

    ... may lose 20 to 40 percent of their muscle -- and, along with it, their strength -- as they ... have found that a major reason people lose muscle is because they stop doing everyday activities that ...

  2. Anti-smooth muscle antibody

    Science.gov (United States)

    ... gov/ency/article/003531.htm Anti-smooth muscle antibody To use the sharing features on this page, please enable JavaScript. Anti-smooth muscle antibody is a blood test that detects the presence ...

  3. MRI appearance of muscle denervation

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, S. [University Hospital of Wales, Department of Radiology, Cardiff (United Kingdom); Venkatanarasimha, N.; Walsh, M.A.; Hughes, P.M. [Derriford Hospital, Department of Radiology, Plymouth (United Kingdom)

    2008-05-15

    Muscle denervation results from a variety of causes including trauma, neoplasia, neuropathies, infections, autoimmune processes and vasculitis. Traditionally, the diagnosis of muscle denervation was based on clinical examination and electromyography. Magnetic resonance imaging (MRI) offers a distinct advantage over electromyography, not only in diagnosing muscle denervation, but also in determining its aetiology. MRI demonstrates characteristic signal intensity patterns depending on the stage of muscle denervation. The acute and subacutely denervated muscle shows a high signal intensity pattern on fluid sensitive sequences and normal signal intensity on T1-weighted MRI images. In chronic denervation, muscle atrophy and fatty infiltration demonstrate high signal changes on T1-weighted sequences in association with volume loss. The purpose of this review is to summarise the MRI appearance of denervated muscle, with special emphasis on the signal intensity patterns in acute and subacute muscle denervation. (orig.)

  4. Calpains in muscle wasting.

    Science.gov (United States)

    Bartoli, Marc; Richard, Isabelle

    2005-10-01

    Calpains are intracellular nonlysosomal Ca(2+)-regulated cysteine proteases. They mediate regulatory cleavages of specific substrates in a large number of processes during the differentiation, life and death of the cell. The purpose of this review is to synthesize our current understanding of the participation of calpains in muscle atrophy. Muscle tissue expresses mainly three different calpains: the ubiquitous calpains and calpain 3. The participation of the ubiquitous calpains in the initial degradation of myofibrillar proteins occurring in muscle atrophy as well as in the necrosis process accompanying muscular dystrophies has been well characterized. Inactivating mutations in the calpain 3 gene are responsible for limb-girdle muscular dystrophy type 2A and calpain 3 has been found to be downregulated in different atrophic situations, suggesting that it has to be absent for the atrophy to occur. The fact that similar regulations of calpain activities occur during exercise as well as in atrophy led us to propose that the calpains control cytoskeletal modifications needed for muscle plasticity.

  5. Inflammatory muscle diseases

    Directory of Open Access Journals (Sweden)

    Mastaglia F

    2008-01-01

    Full Text Available The three major immune-mediated inflammatory myopathies, dermatomyositis (DM, polymyositis (PM and inclusion body myositis (IBM, each have their own distinctive clinical features, underlying pathogenetic mechanisms and patterns of muscle gene expression. In DM a complement-dependent humoral process thought to be initiated by antibodies to endothelial cells results in a microangiopathy with secondary ischemic changes in muscles. On the other hand, in PM and IBM there is a T-cell response with invasion of muscle fibers by CD8+ lymphocytes and perforin-mediated cytotoxic necrosis. In IBM degenerative changes are also a feature and comprise autophagia with rimmed vacuole formation and inclusions containing β-amyloid and other proteins whose accumulation may be linked to impaired proteasomal function. The relationship between the inflammatory and degenerative component remains unclear, as does the basis for the selective vulnerability of certain muscles and the resistance to conventional forms of immunotherapy in most cases of IBM. Patients with DM or PM usually respond to treatment with glucocorticoids and immunosuppressive agents but their use remains largely empirical. Intravenous immunoglobulin therapy can be used to achieve disease control in patients with severe weakness or dysphagia, or in patients with immunodeficiency, but its use is limited by expense. Emerging therapies for resistant cases include TNFα inhibitors (etanercept, infliximab and monoclonal antibodies (rituximab, alemtuzumab. However, experience with these therapies is still limited and there is a need for randomized trials to test their efficacy and establish guidelines for their use in clinical practice.

  6. Physics in muscle research.

    Science.gov (United States)

    Iwazumi, T

    2000-01-01

    Muscle is one of few organs whose performance can be measured by physical quantities. However, very few attempts have been made to apply theoretical physics to muscle. In this paper we will see how physical principles can be applied by taking advantage of unique properties of muscle structure. The first topic is to establish the stability conditions of sarcomere structure. The conclusions are then compared to some experimental facts. Next, we move on to the field theory fundamentals. The concept of energy density as a stress tensor is shown to be a powerful tool for the dielectric force theory to understand how proteins move under electric fields. By combining the structural stability theory and the dielectric force theory we arrive at a helical dipole array. We discuss the source of strong dipole fields and how the dipole strength could be controlled by Ca ions. The behavior of water and ions under electric fields is briefly discussed. The third topic is the mechanical stiffness of muscle in longitudinal and lateral directions. Some experimental data are shown and the physics of anisotropic stiffness is discussed. An appendix is provided to explain the pitfalls of experimenting with isolated components rather than organized structures (sarcomere).

  7. Metabolic Diseases of Muscle

    Science.gov (United States)

    ... inside the cells, pro- ducing energy (ATP) for muscle contraction and other cellular functions. In meta- bolic myopathies, ... after exercising. The exercise-induced cramps (actually sharp contractions that may seem to ... Muscular Dystrophy Association offers a vast array of services ...

  8. Electrical muscle stimulation for deep stabilizing muscles in abdominal wall.

    Science.gov (United States)

    Coghlan, Simon; Crowe, Louis; McCarthyPersson, Ulrik; Minogue, Conor; Caulfield, Brian

    2008-01-01

    Low back pain is associated with dysfunction in recruitment of muscles in the lumbopelvic region. Effective rehabilitation requires preferential activation of deep stabilizing muscle groups. This study was carried out in order to quantify the response of deep stabilizing muscles (transverses abdominis) and superficial muscle in the abdominal wall (external oblique) to electrical muscle stimulation (EMS). Results demonstrate that EMS can preferentially stimulate contractions in the deep stabilizers and may have significant potential as a therapeutic intervention in this area, pending further refinements to the technology.

  9. Nerve-muscle interactions during flight muscle development in Drosophila

    Science.gov (United States)

    Fernandes, J. J.; Keshishian, H.

    1998-01-01

    During Drosophila pupal metamorphosis, the motoneurons and muscles differentiate synchronously, providing an opportunity for extensive intercellular regulation during synapse formation. We examined the existence of such interactions by developmentally delaying or permanently eliminating synaptic partners during the formation of indirect flight muscles. When we experimentally delayed muscle development, we found that although adult-specific primary motoneuron branching still occurred, the higher order (synaptic) branching was suspended until the delayed muscle fibers reached a favourable developmental state. In reciprocal experiments we found that denervation caused a decrease in the myoblast pool. Furthermore, the formation of certain muscle fibers (dorsoventral muscles) was specifically blocked. Exceptions were the adult muscles that use larval muscle fibers as myoblast fusion targets (dorsal longitudinal muscles). However, when these muscles were experimentally compelled to develop without their larval precursors, they showed an absolute dependence on the motoneurons for their formation. These data show that the size of the myoblast pool and early events in fiber formation depend on the presence of the nerve, and that, conversely, peripheral arbor development and synaptogenesis is closely synchronized with the developmental state of the muscle.

  10. Iliopsoas muscle injury in dogs.

    Science.gov (United States)

    Cabon, Quentin; Bolliger, Christian

    2013-05-01

    The iliopsoas muscle is formed by the psoas major and iliacus muscles. Due to its length and diameter, the iliopsoas muscle is an important flexor and stabilizer of the hip joint and the vertebral column. Traumatic acute and chronic myopathies of the iliopsoas muscle are commonly diagnosed by digital palpation during the orthopedic examination. Clinical presentations range from gait abnormalities, lameness, and decreased hip joint extension to irreversible fibrotic contracture of the muscle. Rehabilitation of canine patients has to take into account the inciting cause, the severity of pathology and the presence of muscular imbalances.

  11. Muscle dysfunction in cancer patients

    DEFF Research Database (Denmark)

    Christensen, Jesper Frank; Jones, L W; Andersen, J L

    2014-01-01

    implications of muscle dysfunction in cancer patients. The efficacy of exercise training to prevent and/or mitigate cancer-related muscle dysfunction is also discussed. DESIGN: We identified 194 studies examining muscular outcomes in cancer patients by searching PubMed and EMBASE databases. RESULTS: Muscle......, be powered to evaluate clinical outcomes associated with improvements in muscle function, or be promoted in advanced stage settings, aiming to reverse cancer-related muscle dysfunction, and thus potentially improve time-to-progression, treatment toxicity and survival....

  12. The clinical surface anatomy anomalies of the palmaris longus muscle in the Black African population of Zimbabwe and a proposed new testing technique.

    Science.gov (United States)

    Gangata, Hope

    2009-03-01

    The presence of the palmaris longus muscle (PLM) is highly variable. Rates of absence vary from 0.6% in the Korean population to as high as 63.9% in the Turkish population. The tendon of PLM may be absent on one or both forearms, may have duplicated tendons on one forearm or may be laterally shifted to the extent that the tendon of the PLM lies superficial to that of flexor carpi radialis muscle. Among Black American populations, in which there is usually mixed ancestry, rates of absence are 3.5%. Only two studies have been performed on Black African populations: in Republic of Congo and Uganda, and each showed widely differing rates of absence of 3.0% and 14.6%, respectively. In this study, a total of 890 Black Zimbabwean subjects in Harare aged between 8 and 13 years, were examined for clinical surface anatomy anomalies of the tendon of PLM. The results showed that the tendon of the PLM was absent unilaterally in 0.9% of the population, and bilaterally absent in 0.6% with an overall rate of absence of 1.5%. Other variations noted were a laterally shifted PLM in 1.1% of subjects and duplicated tendons on one forearm, which was the least prevalent anomaly, in 0.2% of subjects. The author proposes a new technique to test the tendon of PLM, which combines resisted thumb abduction and resisted wrist flexion. The proposed technique capitalizes on the role of the PLM as an important abductor of the thumb.

  13. The effects of elbow support on muscle activity and comfort while typing%不同肘部支撑高度对打字时相关肌肉活动及舒适性的影响

    Institute of Scientific and Technical Information of China (English)

    杨锆; 胡海华; 刘加海; 陈岚岚

    2013-01-01

    Objective To observe the effect of elbow support on muscle activity and subjective feelings of comfort during typing.Methods Ten college students voluntarily participated in this experiment.They typed the same text using elbow supports of five different heights.The distance between their elbows and the desk was supported at 3 cm below,0 cm,and-3 cm and-6 cm above the desk.There was also an unsupported condition.Myoelectric readings were recorded from the right splenius,trapezius,biceps,extensor carpi radialis,flexor digitorum superficialis,flexor carpi radialis,and extensor digitorum muscles.Perceptions of comfort of the neck,shoulder,hand and forearm,and hand using the different supports were surveyed using a questionnaire.Results One way ANOVA shows that the height of the elbow significantly affects the activity of the trapezius,the extensor carpi radialis and the extensor digitorum muscles.Trapezius muscle activity was higher with 3 cm high elbow support than without support,and the value was smaller when using-6 cm elbow support.The activity of the carpi radialis longus extensor was least when using-6 cm and-3 cm elbow support,and greatest with 3 cm support.Extensor digitorum activity was least when using-3 cm high elbow support and again greatest with 3 cm support.The different elbow support heights had no significant relationship with comfort perceptions for any body part.Conclusion The height of elbow support can change the average myoelectric signals from muscles during typing,but there is no significant difference in the typist's perception of comfort.This could be due to a change of typing position and neuromuscular motion control mode in response to the height of elbow support.%目的 探讨肘部支撑高度对打字时相关肌肉活动及主观舒适性的影响.方法 选取10名在校大学生为受试者,分别在离桌面3 cm、0 cm、-3 cm、-6 cm及无支撑5种高度下进行打字,利用双极肌电记录系统采集受试者右侧头夹肌

  14. Muscle diseases: the muscular dystrophies.

    Science.gov (United States)

    McNally, Elizabeth M; Pytel, Peter

    2007-01-01

    Dystrophic muscle disease can occur at any age. Early- or childhood-onset muscular dystrophies may be associated with profound loss of muscle function, affecting ambulation, posture, and cardiac and respiratory function. Late-onset muscular dystrophies or myopathies may be mild and associated with slight weakness and an inability to increase muscle mass. The phenotype of muscular dystrophy is an endpoint that arises from a diverse set of genetic pathways. Genes associated with muscular dystrophies encode proteins of the plasma membrane and extracellular matrix, and the sarcomere and Z band, as well as nuclear membrane components. Because muscle has such distinctive structural and regenerative properties, many of the genes implicated in these disorders target pathways unique to muscle or more highly expressed in muscle. This chapter reviews the basic structural properties of muscle and genetic mechanisms that lead to myopathy and muscular dystrophies that affect all age groups.

  15. Dismorfia muscular Muscle dysmorphia

    Directory of Open Access Journals (Sweden)

    Sheila Seleri Marques Assunção

    2002-12-01

    Full Text Available Preocupações mórbidas com a imagem corporal eram tidas até recentemente como problemas eminentemente femininos. Atualmente estas preocupações também têm sido encontradas no sexo masculino. A dismorfia muscular é um subtipo do transtorno dismórfico corporal que ocorre principalmente em homens que, apesar da grande hipertrofia muscular, consideram-se pequenos e fracos. Além de estar associada a prejuízos sociais, ocupacionais, recreativos e em outras áreas do funcionamento do indivíduo, a dismorfia muscular é também um fator de risco para o abuso de esteróides anabolizantes. Este artigo aborda aspectos epidemiológicos, etiológicos e padrões clínicos da dismorfia muscular, além de tecer comentários sobre estratégias de tratamento para este transtorno.Morbid concern over body image was considered, until recently, a female issue. Nowadays, it has been viewed as a common male disorder. Muscle dysmorphia, a subtype of a body dysmorphic disorder, affects men who, despite having clear muscular hypertroph,y see themselves as frail and small. Besides being associated to major social, leisure and occupational dysfunction, muscle dysmorphia is also a risk factor for the abuse of steroids. This article describes epidemiological, etiological and clinical characteristics of muscle dysmorphia and comments on its treatment strategy.

  16. Creating an Artificial Muscle

    Science.gov (United States)

    Bohon, Katherine; Krause, Sonja

    1997-03-01

    Striated skeletal muscle responds to a nerve impulse in less than 100 ms. In the past, polymeric gels and conducting polymers have been investigated for use as artificial muscle. However, the main problem with these materials is their relatively slow response (>3 seconds). On the other hand, electrorheological (ER) fluids are materials that change from a liquid to a solid upon application of an electric field. These fluids have a response on the order of a millisecond. A novel approach to artificial muscle utilizing the fast time response of ER fluids and the elasticity of polymeric gels has been investigated. A commercial sample of a two-part poly(dimethyl siloxane) (PDMS) dielectric gel was used. The PDMS was cured around two flexible electrodes 5 mm apart while a mixture of PDMS with solvent was cured between the electrodes. The solvents were either silicone oil or an ER fluid composed of crosslinked poly(ethylene oxide) (PEO) particles in silicone oil. The mixtures investigated were 90/10, 60/40, 50/50, 40/60, 10/90 PDMS/solvent. Upon application of a 6.2 kV/cm DC electric field the gel was reversibly compressed. The time response of the gel was actuator has been created using the 60/40 PDMS/ER fluid mixture.

  17. [Delayed post effort muscle soreness].

    Science.gov (United States)

    Coudreuse, J M; Dupont, P; Nicol, C

    2004-08-01

    Muscle intolerance to exercise may result from different processes. Diagnosis involves confirming first the source of pain, then potential pathological myalgia. Delayed-onset muscle soreness (DOMS), commonly referred as tiredness, occurs frequently in sport. DOMS usually develops 12-48 h after intensive and/or unusual eccentric muscle action. Symptoms usually involve the quadriceps muscle group but may also affect the hamstring and triceps surae groups. The muscles are sensitive to palpation, contraction and passive stretch. Acidosis, muscle spasm and microlesions in both connective and muscle tissues may explain the symptoms. However, inflammation appears to be the most common explanation. Interestingly, there is strong evidence that the progression of the exercise-induced muscle injury proceeds no further in the absence of inflammation. Even though unpleasant, DOMS should not be considered as an indicator of muscle damage but, rather, a sign of the regenerative process, which is well known to contribute to the increased muscle mass. DOMS can be associated with decreased proprioception and range of motion, as well as maximal force and activation. DOMS disappears 2-10 days before complete functional recovery. This painless period is ripe for additional joint injuries. Similarly, if some treatments are well known to attenuate DOMS, none has been demonstrated to accelerate either structural or functional recovery. In terms of the role of the inflammatory process, these treatments might even delay overall recovery.

  18. Painful Unilateral Temporalis Muscle Enlargement: Reactive Masticatory Muscle Hypertrophy

    OpenAIRE

    Katsetos, Christos D.; Bianchi, Michael A.; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2013-01-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptoma...

  19. PDH regulation in skeletal muscle

    DEFF Research Database (Denmark)

    Kiilerich, Kristian

    is determined by the overall content / activity of the regulatory proteins PDH kinase (PDK), of which there are 4 isoforms, and PDH phosphatase (PDP), of which there are 2 isoforms. The overall aim of the PhD project was to elucidate 4 issues. 1: Role of muscle type in resting and exercise-induced PDH...... in arm than leg muscles during exercise in humans may be the result of lower PDH-E1? content and not a muscle type dependent difference in PDH regulation. Both low muscle glycogen and increased plasma FFA are associated with upregulation of PDK4 protein and less exercise-induced increase in PDHa activity...... in human skeletal muscle. It may be noted that the increased PDK4 protein associated with elevated plasma FFA occurs already 2 hours after different dietary intake. A week of physical inactivity (bed rest), leading to whole body glucose intolerance, does not affect muscle PDH-E1? content, or the exercise...

  20. Muscle dysfunction in male hypogonadism.

    Science.gov (United States)

    Chauhan, A K; Katiyar, B C; Misra, S; Thacker, A K; Singh, N K

    1986-05-01

    Twenty-eight consecutive male patients with primary and secondary hypogonadism (14 each) were evaluated clinically and electrophysiologically for muscle dysfunction. Although generalised muscle weakness was initially reported by only 9 patients, on direct questioning, it was recorded in 19. Objective weakness was found in 13 patients and it involved both the proximal and distal limb muscles. Quantitative electromyography showed evidence of myopathy in the proximal muscle in 25 patients, i.e., reduced MUP duration and amplitude with increased polyphasia in the deltoid and the gluteus maximus. There were no denervation potentials. None of the patients showed clinical neuropathy or NCV abnormalities. Thus, the profile of muscle involvement in hypogonadism closely simulates limb-girdle muscular dystrophy and other endocrine myopathies. The incidence of muscle involvement was higher in secondary hypogonadism. Diminished androgens in primary hypogonadism and diminished growth hormone in the secondary hypogonadism are probably responsible for the myopathy.

  1. Muscle strength in myasthenia gravis

    DEFF Research Database (Denmark)

    Cejvanovic, S; Vissing, J

    2014-01-01

    is related to disease duration or gender. The aim of this study was to quantify the strength of patients with MG and investigate whether it is related to disease duration. METHODS: Eight muscle groups were tested by manual muscle testing and with a hand-held dynamometer in 38 patients with generalized MG...... and 37 healthy age- and gender-matched controls. The disease duration was recorded and compared with strength measures. RESULTS: On average, muscle strength was decreased by 28% compared with controls (Pstrength measures in individual patients did not differ, suggesting that the muscle...... force reported was not subject to fatigue, but reflected fixed weakness. The male patients showed a greater reduction in muscle force in all eight muscle groups than women with MG (60% vs 77% of normal, Pstrength in shoulder abductors was most affected (51% vs 62...

  2. [Myoma of the breast muscle].

    Science.gov (United States)

    Peteiro, M C; Fernández-Redondo, V; Zulaica, A; Toribio, J

    1985-01-01

    A female patient presented with a tumoral lesion of the areola of the left breast; the lesion surrounded the nipple. Histopathologically there was proliferation of smooth muscle fibers of the middle and deep layers of the dermis; the papillary dermis was not affected. Myomas in this site do not present the typical characteristics of other kinds of leiomyomas, including those of the scrotum. Therefore, mamillary muscle myomas should not be considered authentic tumors, but rather smooth muscle hyperplasias.

  3. Muscle dysmorphia: current insights.

    Science.gov (United States)

    Tod, David; Edwards, Christian; Cranswick, Ieuan

    2016-01-01

    Since 1997, there has been increasing research focusing on muscle dysmorphia, a condition underpinned by people's beliefs that they have insufficient muscularity, in both the Western and non-Western medical and scientific communities. Much of this empirical interest has surveyed nonclinical samples, and there is limited understanding of people with the condition beyond knowledge about their characteristics. Much of the existing knowledge about people with the condition is unsurprising and inherent in the definition of the disorder, such as dissatisfaction with muscularity and adherence to muscle-building activities. Only recently have investigators started to explore questions beyond these limited tautological findings that may give rise to substantial knowledge advances, such as the examination of masculine and feminine norms. There is limited understanding of additional topics such as etiology, prevalence, nosology, prognosis, and treatment. Further, the evidence is largely based on a small number of unstandardized case reports and descriptive studies (involving small samples), which are largely confined to Western (North American, British, and Australian) males. Although much research has been undertaken since the term "muscle dysmorphia" entered the psychiatric lexicon in 1997, there remains tremendous scope for knowledge advancement. A primary task in the short term is for investigators to examine the extent to which the condition exists among well-defined populations to help determine the justification for research funding relative to other public health issues. A greater variety of research questions and designs may contribute to a broader and more robust knowledge base than currently exists. Future work will help clinicians assist a group of people whose quality of life and health are placed at risk by their muscular preoccupation.

  4. Nutritional interventions to preserve skeletal muscle mass

    NARCIS (Netherlands)

    Backx, Evelien M.P.

    2016-01-01

    Muscle mass is the main predictor for muscle strength and physical function. The amount of muscle mass can decline rapidly during periods of reduced physical activity or during periods of energy intake restriction. For athletes, it is important to maintain muscle mass, since the loss of muscle is as

  5. Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-inspired Robotic Hand for Prosthetic Applications

    Directory of Open Access Journals (Sweden)

    Simone Fani

    2016-10-01

    Full Text Available Myoelectric-artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human-likeness of prosthesis movements, a goal which is being pursued by research on social and human-robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed such as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an under-actuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e. flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography

  6. Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-Inspired Robotic Hand for Prosthetic Applications

    Science.gov (United States)

    Fani, Simone; Bianchi, Matteo; Jain, Sonal; Pimenta Neto, José Simões; Boege, Scott; Grioli, Giorgio; Bicchi, Antonio; Santello, Marco

    2016-01-01

    Myoelectric artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human likeness of prosthesis movements, a goal which is being pursued by research on social and human–robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed so as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an underactuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e., flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography-to-position mapping ensured

  7. Muscling out malaria

    DEFF Research Database (Denmark)

    Hughes, David Peter; Boomsma, Jacobus Jan

    2006-01-01

    of the pathogenic fungi concerned. There is a long history of using Metarhizium and Beauveria in insect biocontrol [6] with ‘Green Muscle', a broad consortium set up to control locusts using Metarhizium, as an excellent example (for more information, see http://www.sciencedirect.com/science?_ob=RedirectURL&_method=externObjLink&_locator=url......&_cdi=6081&_plusSign=%2B&_targetURL=http%253A%252F%252Fwww.lubilosa.org%252F ). Green Muscle developed from the initial conception that spores could be suspended in oil to facilitate germination in arid regions [7] , which made infecting mosquitoes feasible [4] . However, failures in biocontrol have been...... surveying as part of interdisciplinary programs, comparable to expeditions organised by the British Mycological Society ( http://www.sciencedirect.com/science?_ob=RedirectURL&_method=externObjLink&_locator=url&_cdi=6081&_plusSign=%2B&_targetURL=http%253A%252F%252Fwww.britmycolsoc.org.uk%252F [14] ). Finally...

  8. Elicitability of muscle cramps in different leg and foot muscles.

    Science.gov (United States)

    Minetto, Marco Alessandro; Botter, Alberto

    2009-10-01

    To explore the efficacy of muscle motor point stimulation in eliciting muscle cramps, 11 subjects underwent eight sessions of electrical stimulation of the following muscles bilaterally: abductor hallucis flexor hallucis brevis, and both heads of the gastrocnemius muscles. Bursts of 150 square wave stimuli (duration: 152 micros; current intensity: 30% supramaximal) were applied. The stimulation frequency was increased from 4 pulses per second (pps) at increments of 2 pps until a cramp was induced. The number of cramps that could be elicited was smaller in flexor hallucis brevis than in abductor hallucis (16 vs. 22 out of 22 trials each; P muscles have different cramp susceptibility, and the intermuscle variability in the elicitability profile for electrically induced cramps supports the use of the proposed method for cramp research.

  9. Building Muscles, Keeping Muscles: Protein Turnover During Space Flight

    Science.gov (United States)

    Ferrando, Arny; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

    2002-01-01

    As we age we lose muscle mass and strength. The problem is a matter of use it or lose it and more - a fact to which any active senior can attest. An imbalance in the natural cycle of protein turnover may be a contributing factor to decreased muscle mass. But the answer is not so simple, since aging is associated with changes in hormones, activity levels, nutrition, and often, disease. The human body constantly uses amino acids to build muscle protein, which then breaks down and must be replaced. When protein turnover gets out of balance, so that more protein breaks down than the body can replace, the result is muscle loss. This is not just the bane of aging, however. Severely burned people may have difficulty building new muscle long after the burned skin has been repaired. Answers to why we lose muscle mass and strength - and how doctors can fix it - may come from space. Astronauts usually eat a well-balanced diet and maintain an exercise routine to stay in top health. During long-duration flight, they exercise regularly to reduce the muscle loss that results from being in a near-weightless environment. Despite these precautions, astronauts lose muscle mass and strength during most missions. They quickly recover after returning to Earth - this is a temporary condition in an otherwise healthy population. Members of the STS-107 crew are participating in a study of the effects of space flight, hormone levels, and stress on protein turnover. When we are under stress, the body responds with a change in hormone levels. Researchers hypothesize that this stress-induced change in hormones along with the near-weightlessness might result in the body synthesizing less muscle protein, causing muscles to lose their strength and size. Astronauts, who must perform numerous duties in a confined and unusual environment, experience some stress during their flight, making them excellent candidates for testing the researchers' hypothesis.

  10. Aging changes in the bones - muscles - joints

    Science.gov (United States)

    ... because of changes in the muscle tissue and normal aging changes in the nervous system . Muscles may become rigid ... knee jerk or ankle jerk can occur. Some changes, such as a positive ... Involuntary movements (muscle tremors and fine movements called ...

  11. Infraspinatus muscle atrophy from suprascapular nerve compression.

    Science.gov (United States)

    Cordova, Christopher B; Owens, Brett D

    2014-02-01

    Muscle weakness without pain may signal a nerve compression injury. Because these injuries should be identified and treated early to prevent permanent muscle weakness and atrophy, providers should consider suprascapular nerve compression in patients with shoulder muscle weakness.

  12. Trichinella spiralis in human muscle (image)

    Science.gov (United States)

    This is the parasite Trichinella spiralis in human muscle tissue. The parasite is transmitted by eating undercooked ... produce large numbers of larvae that migrate into muscle tissue. The cysts may cause muscle pain and ...

  13. Sternalis muscle: a mystery still.

    Science.gov (United States)

    Loukas, Marios; Bowers, Maggi; Hullett, Joel

    2004-05-01

    Despite intensive anatomical research during the last century, anatomical structures or variations of these structures may still cause confusion or even iatrogenic injury. A matter of debate is the sternalis muscle. We present a review of the literature of the sternalis muscle with special emphasis on its clinical anatomy.

  14. Muscle ultrasound in neuromuscular disorders.

    NARCIS (Netherlands)

    Pillen, S.; Arts, I.M.P.; Zwarts, M.J.

    2008-01-01

    Muscle ultrasound is a useful tool in the diagnosis of neuromuscular disorders, as these disorders result in muscle atrophy and intramuscular fibrosis and fatty infiltration, which can be visualized with ultrasound. Several prospective studies have reported high sensitivities and specificities in th

  15. The Basis of Muscle Regeneration

    Directory of Open Access Journals (Sweden)

    Antonio Musarò

    2014-01-01

    Full Text Available Muscle regeneration recapitulates many aspects of embryonic myogenesis and is an important homeostatic process of the adult skeletal muscle, which, after development, retains the capacity to regenerate in response to appropriate stimuli, activating the muscle compartment of stem cells, namely, satellite cells, as well as other precursor cells. Moreover, significant evidence suggests that while stem cells represent an important determinant for tissue regeneration, a “qualified” environment is necessary to guarantee and achieve functional results. It is therefore plausible that the loss of control over these cell fate decisions could lead to a pathological transdifferentiation, leading to pathologic defects in the regenerative process. This review provides an overview about the general aspects of muscle development and discusses the cellular and molecular aspects that characterize the five interrelated and time-dependent phases of muscle regeneration, namely, degeneration, inflammation, regeneration, remodeling, and maturation/functional repair.

  16. Muscle regeneration in mitochondrial myopathies

    DEFF Research Database (Denmark)

    Krag, T O; Hauerslev, S; Jeppesen, T D;

    2013-01-01

    Mitochondrial myopathies cover a diverse group of disorders in which ragged red and COX-negative fibers are common findings on muscle morphology. In contrast, muscle degeneration and regeneration, typically found in muscular dystrophies, are not considered characteristic features of mitochondrial...... myopathies. We investigated regeneration in muscle biopsies from 61 genetically well-defined patients affected by mitochondrial myopathy. Our results show that the perturbed energy metabolism in mitochondrial myopathies causes ongoing muscle regeneration in a majority of patients, and some were even affected...... by a dystrophic morphology. The results add to the complexity of the pathogenesis underlying mitochondrial myopathies, and expand the knowledge about the impact of energy deficiency on another aspect of muscle structure and function....

  17. Complement activation promotes muscle inflammation during modified muscle use

    Science.gov (United States)

    Frenette, J.; Cai, B.; Tidball, J. G.

    2000-01-01

    Modified muscle use can result in muscle inflammation that is triggered by unidentified events. In the present investigation, we tested whether the activation of the complement system is a component of muscle inflammation that results from changes in muscle loading. Modified rat hindlimb muscle loading was achieved by removing weight-bearing from the hindlimbs for 10 days followed by reloading through normal ambulation. Experimental animals were injected with the recombinant, soluble complement receptor sCR1 to inhibit complement activation. Assays for complement C4 or factor B in sera showed that sCR1 produced large reductions in the capacity for activation of the complement system through both the classical and alternative pathways. Analysis of complement C4 concentration in serum in untreated animals showed that the classical pathway was activated during the first 2 hours of reloading. Analysis of factor B concentration in untreated animals showed activation of the alternative pathway at 6 hours of reloading. Administration of sCR1 significantly attenuated the invasion of neutrophils (-49%) and ED1(+) macrophages (-52%) that occurred in nontreated animals after 6 hours of reloading. The presence of sCR1 also reduced significantly the degree of edema by 22% as compared to untreated animals. Together, these data show that increased muscle loading activated the complement system which then briefly contributes to the early recruitment of inflammatory cells during modified muscle loading.

  18. Intermuscular pressure between synergistic muscles correlates with muscle force.

    Science.gov (United States)

    Reinhardt, Lars; Siebert, Tobias; Leichsenring, Kay; Blickhan, Reinhard; Böl, Markus

    2016-08-01

    The purpose of the study was to examine the relationship between muscle force generated during isometric contractions (i.e. at a constant muscle-tendon unit length) and the intermuscular (between adjacent muscles) pressure in synergistic muscles. Therefore, the pressure at the contact area of the gastrocnemius and plantaris muscle was measured synchronously to the force of the whole calf musculature in the rabbit species Oryctolagus cuniculus Similar results were obtained when using a conductive pressure sensor, or a fibre-optic pressure transducer connected to a water-filled balloon. Both methods revealed a strong linear relationship between force and pressure in the ascending limb of the force-length relationship. The shape of the measured force-time and pressure-time traces was almost identical for each contraction (r=0.97). Intermuscular pressure ranged between 100 and 700 mbar (70,000 Pa) for forces up to 287 N. These pressures are similar to previous (intramuscular) recordings within skeletal muscles of different vertebrate species. Furthermore, our results suggest that the rise in intermuscular pressure during contraction may reduce the force production in muscle packages (compartments).

  19. Skeletal muscle connective tissue

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline

      The connective tissue content of skeletal muscle is believed to be the major factor responsible for defining the eating quality of different meat cuts, although attempts to correlate quantifications based on traditional histological methods have not as yet been able to prove this relation....... Collagen, being the major protein in connective tissue, has been extensively investigated with regard to its relation to meat tenderness, but the results have been rather conflicting. Meat from older animals is tougher than that from younger animals, and changes in the properties of the collagen due...... that collagen plays a significant role in determining the tenderness of meat. What are we missing? Therefore, fundamental aspects of connective tissue research have been the centre of attention throughout this thesis. A holistic view has been applied, glancing at this complex tissue which has many facets...

  20. Development of Postural Muscles and Their Innervation

    Directory of Open Access Journals (Sweden)

    J. IJkema-Paassen

    2005-01-01

    Full Text Available Control of posture is a prerequisite for efficient motor performance. Posture depends on muscles capable of enduring contractions, whereas movements often require quick, forceful muscle actions. To serve these different goals, muscles contain fibers that meet these different tasks. Muscles with strong postural functions mainly consist of slow muscle fibers with a great resistance against fatigue. Flexor muscles in the leg and arm muscles are mainly composed of fast muscle fibers producing relatively large forces that are rapidly fatigable. Development of the neuromuscular system continues after birth. We discuss in the human baby and in animal experiments changes in muscle fiber properties, regression from polyneural into mononeural innervation, and developmental changes in the motoneurons of postural muscles during that period. The regression of poly-neural innervation in postural muscles and the development of dendrite bundles of their motoneurons seem to be linked to the transition from the immature into the adult-like patterns of moving and postural control.

  1. Muscle channelopathies and electrophysiological approach

    Directory of Open Access Journals (Sweden)

    Cherian Ajith

    2008-01-01

    Full Text Available Myotonic syndromes and periodic paralyses are rare disorders of skeletal muscle characterized mainly by muscle stiffness or episodic attacks of weakness. Familial forms are caused by mutation in genes coding for skeletal muscle voltage ionic channels. Familial periodic paralysis and nondystrophic myotonias are disorders of skeletal muscle excitability caused by mutations in genes coding for voltage-gated ion channels. These diseases are characterized by episodic failure of motor activity due to muscle weakness (paralysis or stiffness (myotonia. Clinical studies have identified two forms of periodic paralyses: hypokalemic periodic paralysis (hypoKPP and hyperkalemic periodic paralysis (hyperKPP, based on changes in serum potassium levels during the attacks, and three distinct forms of myotonias: paramyotonia congenita (PC, potassium-aggravated myotonia (PAM, and myotonia congenita (MC. PC and PAM have been linked to missense mutations in the SCN4A gene, which encodes α subunit of the voltage-gated sodium channel, whereas MC is caused by mutations in the chloride channel gene (CLCN1. Exercise is known to trigger, aggravate, or relieve symptoms. Therefore, exercise can be used as a functional test in electromyography to improve the diagnosis of these muscle disorders. Abnormal changes in the compound muscle action potential can be disclosed using different exercise tests. Five electromyographic (EMG patterns (I-V that may be used in clinical practice as guides for molecular diagnosis are discussed.

  2. Factors in delayed muscle soreness.

    Science.gov (United States)

    Abraham, W M

    1977-01-01

    The possible causes of delayed muscle soreness which occur 24 to 48 hr after exercise were examined from three different approaches, each designed to test an existing hypothesis. Surface electromyograms were used to evaluate the muscle spasm theory; the possibility of actual muscle cell damage was monitored by the presence of myoglobinuria, while the ratio of hydroxyproline/creatinine (OHP/Cr) in 24 hr urine collection was used as a marker for connective tissue involvement. In the first study, although all volunteers developed muscle soreness 24 and 48 hr after exercise, no change in the EMG activity of the sore muscles was observed. Myoglobin excretion was found in 88% of the subjects who developed soreness. However, in a second study, 92% of the subject who performed both moderate and heavy exercise but did not develop muscle soreness had myoglobinuria. In contrast, during a third experiment subjects on gelatin-free diets showed an increase (P less than .1) in the OHP/Cr between control (.020+/-.001) and 48 hr post-exercise (.002+/-.001, X+/-SE). Soreness resulted in all cases. When the OHP/Cr value is taken for the day of maximal soreness, the post-exercise mean increases to .024+/-.001 and the level of significance rises (P less than .005). These observations support the concept that exercise induced soreness may be related to disruption of the connective tissue elements in the muscle and/or their attachments.

  3. [Muscles and connective tissue: histology].

    Science.gov (United States)

    Delage, J-P

    2012-10-01

    Here, we give some comments about the DVD movies "Muscle Attitudes" from Endovivo productions, the movies up lighting some loss in the attention given to studies on the connective tissue, and especially them into muscles. The main characteristics of the different components in the intra-muscular connective tissue (perimysium, endomysium, epimysium) are shown here with special references to their ordered architecture and special references to their spatial distributions. This connective tissue is abundant into the muscles and is in continuity with the muscles in vicinity, with their tendons and their sheath, sticking the whole on skin. This connective tissue has also very abundant connections on the muscles fibres. It is then assumed that the connective tissue sticks every organs or cells of the locomotion system. Considering the elastic properties of the collagen fibres which are the most abundant component of connective tissue, it is possible to up light a panel of connective tissue associated functions such as the transmission of muscle contractions or the regulation of protein and energetic muscles metabolism.

  4. Posterior interosseous free flap: various types.

    Science.gov (United States)

    Park, J J; Kim, J S; Chung, J I

    1997-10-01

    The posterior interosseous artery is located in the intermuscular septum between the extensor carpi ulnaris and extensor digiti minimi muscles. The posterior interosseous artery is anatomically united through two main anastomoses: one proximal (at the level of the distal border of the supinator muscle) and one distal (at the most distal part of the interosseous space). In the distal part, the posterior interosseous artery joins the anterior interosseous artery to form the distal anastomosis between them. The posterior interosseous flap can be widely used as a reverse flow island flap because it is perfused by anastomoses between the anterior and the posterior interosseous arteries at the level of the wrist. The flap is not reliable whenever there is injury to the distal forearm or the wrist. To circumvent this limitation and to increase the versatility of this flap, we have refined its use as a direct flow free flap. The three types of free flaps used were (1) fasciocutaneous, (2) fasciocutaneous-fascia, and (3) fascia only. Described are 23 posterior interosseous free flaps: 13 fasciocutaneous flaps, 6 fasciocutaneous-fascial flaps, and 4 fascial flaps. There were 13 sensory flaps using the posterior antebrachial cutaneous nerve. The length and external diameter of the pedicle were measured in 35 cases. The length of the pedicle was on average 3.5 cm (range, 3.0 to 4.0 cm) and the external diameter of the artery averaged 2.2 mm (range, 2.0 to 2.5 mm). The hand was the recipient in 21 patients, and the foot in 2. All 23 flaps covered the defect successfully.

  5. Skeletal Muscle Na+ Channel Disorders

    Directory of Open Access Journals (Sweden)

    Dina eSimkin

    2011-10-01

    Full Text Available Five inherited human disorders affecting skeletal muscle contraction have been traced to mutations in the gene encoding the voltage-gated sodium channel Nav1.4. The main symptoms of these disorders are myotonia or periodic paralysis caused by changes in skeletal muscle fiber excitability. Symptoms of these disorders vary from mild or latent disease to incapacitating or even death in severe cases. As new human sodium channel mutations corresponding to disease states become discovered, the importance of understanding the role of the sodium channel in skeletal muscle function and disease state grows.

  6. Bigorexia: bodybuilding and muscle dysmorphia.

    Science.gov (United States)

    Mosley, Philip E

    2009-05-01

    Muscle dysmorphia is an emerging condition that primarily affects male bodybuilders. Such individuals obsess about being inadequately muscular. Compulsions include spending hours in the gym, squandering excessive amounts of money on ineffectual sports supplements, abnormal eating patterns or even substance abuse. In this essay, I illustrate the features of muscle dysmorphia by employing the first-person account of a male bodybuilder afflicted by this condition. I briefly outline the history of bodybuilding and examine whether the growth of this sport is linked to a growing concern with body image amongst males. I suggest that muscle dysmorphia may be a new expression of a common pathology shared with the eating disorders.

  7. Compensatory Hypertrophy of Skeletal Muscle: Contractile Characteristics

    Science.gov (United States)

    Ianuzzo, C. D.; Chen, V.

    1977-01-01

    Describes an experiment using rats that demonstrates contractile characteristics of normal and hypertrophied muscle. Compensatory hypertrophy of the plantaris muscle is induced by surgical removal of the synergistic gastrocnemium muscle. Includes methods for determination of contractile properties of normal and hypertrophied muscle and…

  8. Contractile Properties of Esophageal Striated Muscle: Comparison with Cardiac and Skeletal Muscles in Rats

    Directory of Open Access Journals (Sweden)

    Takahiko Shiina

    2010-01-01

    Full Text Available The external muscle layer of the mammalian esophagus consists of striated muscles. We investigated the contractile properties of esophageal striated muscle by comparison with those of skeletal and cardiac muscles. Electrical field stimulation with single pulses evoked twitch-like contractile responses in esophageal muscle, similar to those in skeletal muscle in duration and similar to those in cardiac muscle in amplitude. The contractions of esophageal muscle were not affected by an inhibitor of gap junctions. Contractile responses induced by high potassium or caffeine in esophageal muscle were analogous to those in skeletal muscle. High-frequency stimulation induced a transient summation of contractions followed by sustained contractions with amplitudes similar to those of twitch-like contractions, although a large summation was observed in skeletal muscle. The results demonstrate that esophageal muscle has properties similar but not identical to those of skeletal muscle and that some specific properties may be beneficial for esophageal peristalsis.

  9. Knitting and weaving artificial muscles

    Science.gov (United States)

    Maziz, Ali; Concas, Alessandro; Khaldi, Alexandre; Stålhand, Jonas; Persson, Nils-Krister; Jager, Edwin W. H.

    2017-01-01

    A need exists for artificial muscles that are silent, soft, and compliant, with performance characteristics similar to those of skeletal muscle, enabling natural interaction of assistive devices with humans. By combining one of humankind’s oldest technologies, textile processing, with electroactive polymers, we demonstrate here the feasibility of wearable, soft artificial muscles made by weaving and knitting, with tunable force and strain. These textile actuators were produced from cellulose yarns assembled into fabrics and coated with conducting polymers using a metal-free deposition. To increase the output force, we assembled yarns in parallel by weaving. The force scaled linearly with the number of yarns in the woven fabric. To amplify the strain, we knitted a stretchable fabric, exhibiting a 53-fold increase in strain. In addition, the textile construction added mechanical stability to the actuators. Textile processing permits scalable and rational production of wearable artificial muscles, and enables novel ways to design assistive devices. PMID:28138542

  10. Muscle glycogen stores and fatigue

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Westerblad, Håkan; Nielsen, Joachim

    2013-01-01

      Studies performed at the beginning of the last century revealed the importance of carbohydrate as a fuel during exercise, and the importance of muscle glycogen on performance has subsequently been confirmed in numerous studies. However, the link between glycogen depletion and impaired muscle...... function during fatigue is not well understood and a direct cause-and-effect relationship between glycogen and muscle function remains to be established. The use of electron microscopy has revealed that glycogen is not homogeneously distributed in skeletal muscle fibres, but rather localized in distinct...... pools. Furthermore, each glycogen granule has its own metabolic machinery with glycolytic enzymes and regulating proteins. One pool of such glycogenolytic complexes is localized within the myofibrils in close contact with key proteins involved in the excitation-contraction coupling and Ca2+ release from...

  11. Muscle Strength and Poststroke Hemiplegia

    DEFF Research Database (Denmark)

    Kristensen, Otto H; Stenager, Egon; Dalgas, Ulrik

    2017-01-01

    OBJECTIVES: To systematically review (1) psychometric properties of criterion isokinetic dynamometry testing of muscle strength in persons with poststroke hemiplegia (PPSH); and (2) literature that compares muscle strength in patients poststroke with that in healthy controls assessed by criterion...... isokinetic dynamometry. DATA SOURCES: A systematic literature search of 7 databases was performed. STUDY SELECTION: Included studies (1) enrolled participants with definite poststroke hemiplegia according to defined criteria; (2) assessed muscle strength or power by criterion isokinetic dynamometry; (3) had...... undergone peer review; and (4) were available in English or Danish. DATA EXTRACTION: The psychometric properties of isokinetic dynamometry were reviewed with respect to reliability, validity, and responsiveness. Furthermore, comparisons of strength between paretic, nonparetic, and comparable healthy muscles...

  12. Sports Hernia: Misdiagnosed Muscle Strain

    Science.gov (United States)

    ... next step in treatment. During surgery, the lower abdominal muscles and connective tissues are released and reattached. Some ... a Training Program Postdoctoral Training OPTI Clearinghouse OGME Development Physician Profiles Order Physician Credentialing Reports Professional Development ...

  13. Evaluation of muscle hyperactivity of the grimacing muscles by unilateral tight eyelid closure and stapedius muscle tone.

    Science.gov (United States)

    Shiba, Masato; Matsuo, Kiyoshi; Ban, Ryokuya; Nagai, Fumio

    2012-10-01

    Muscle hyperactivity of grimacing muscles, including the orbicularis oculi and corrugator supercilii muscles that cause crow's feet and a glabellar frown line with ageing, cannot be accurately evaluated by surface observation. In 71 subjects, this study investigated the extent to which grimacing muscles are innervated by the bilateral motor cortices, whether the corticofacial projection to the grimacing muscles affects the facially innervated stapedius muscle tone by measuring static compliance of the tympanic membrane, and whether unilateral tight eyelid closure with contraction of the grimacing muscles changes static compliance. Unilateral tight eyelid closure and its subsequent change in the contralateral vertical medial eyebrow position revealed that motor neurons of the orbicularis oculi and corrugator supercilii muscles were innervated by the bilateral motor cortices with weak-to-strong contralateral dominance. The orbicularis oculi, corrugator supercilii, and stapedius muscles innervated by the bilateral motor cortices had increased muscle hyperactivity, which lowered the vertical medial eyebrow position and decreased the static compliance of the tympanic membrane more than those innervated by the unilateral motor cortex. Unilateral enhanced tight eyelid closure with contraction of the grimacing muscles in certain subjects ipsilaterally decreased the static compliance with increased contraction of the stapedius muscle, which probably occurs to immobilise the tympanic membrane and protect the inner ear from loud sound. Evaluation of unilateral tight eyelid closure and the subsequent change in the contralateral vertical medial eyebrow position as well as a measurement of the static compliance for the stapedius muscle tone has revealed muscle hyperactivity of grimacing muscles.

  14. Simvastatin effects on skeletal muscle

    DEFF Research Database (Denmark)

    Larsen, Steen; Stride, Nis; Hey-Mogensen, Martin;

    2013-01-01

    Glucose tolerance and skeletal muscle coenzyme Q(10) (Q(10)) content, mitochondrial density, and mitochondrial oxidative phosphorylation (OXPHOS) capacity were measured in simvastatin-treated patients (n = 10) and in well-matched control subjects (n = 9).......Glucose tolerance and skeletal muscle coenzyme Q(10) (Q(10)) content, mitochondrial density, and mitochondrial oxidative phosphorylation (OXPHOS) capacity were measured in simvastatin-treated patients (n = 10) and in well-matched control subjects (n = 9)....

  15. Putting muscle in DNA methylation

    Institute of Scientific and Technical Information of China (English)

    James P Reddington; Richard R Meehan

    2011-01-01

    Over 25 years ago seminal experiments from the labs of Peter Jones and Harold Weintraub demonstrated that alteration in the DNA modification state underlie the myogenic conversion of fibroblast cell lines [1,2].This paved the way for the identification of myogenic helix-loop-helix (HLH) proteins in muscle differentiation,but the mechanism by which DNA methylation regulates muscle differentiation has remained elusive [3].

  16. Morphology of peroneus tertius muscle.

    Science.gov (United States)

    Joshi, S D; Joshi, S S; Athavale, S A

    2006-10-01

    Peroneus tertius (PT) muscle is peculiar to man, and man is the only member among the primates in whom this muscle occurs. The muscle is variable in its development and attachment. Because of functional demands of bipedal gait and plantigrade foot, part of extensor digitorum brevis (EDB) has migrated upwards into the leg from the dorsum of foot. PT is a muscle that evolution is rendering more important. In a total of 110 cadavers, extensor compartment of leg and dorsum of foot were dissected in both the lower limbs and extensor digitorum longus (EDL), and PT muscles were dissected and displayed. PT was found to be absent in 10.5% limbs, the incidence being greater on the right side. The remaining limbs in which the PT muscle was present had a very extensive origin from lower 3/4th of extensor surface of fibula (20% on right and in 17% on left), and the EDL was very much reduced in size. In approximately 12%, the tendon of PT was thick or even thicker than the tendon of EDL. In 4%, the tendon extended beyond fifth metatarsal up to metatarsophalangeal joint of fifth toe, and in 1.5%, it extended up to the proximal phalanx of little toe. In two cases (both on the right side), where PT was absent, it was replaced by a slip from lateral margin of EDL. We conclude that PT, which is preeminently human, is extending its purchase both proximally and distally.

  17. Muscle histochemistry in chronic alcoholism

    Directory of Open Access Journals (Sweden)

    M. L. Ferraz

    1989-06-01

    Full Text Available Twenty-two chronic acoholic patients were assessed by neurologic examination and muscle biopsy. The patients manifested proximal muscular weakness to a variable extent. One case presented as an acute bout of myopathy, according to the Manual Muscle Test, MMT. The most prominent histologic feature observed was muscle atrophy (95.3% better evidenced through the ATPase stain with the predominance of type II A fibers (71.4%. Lack of the mosaic pattern (type grouping seen in 76% of the cases and an important mitochondrial proliferation with intrasarcoplasmatic lipid accumulation in 63% of the patients. In case of acute presentation of muscle weakness the. pathological substrate is quite different, i.e. presence of myositis mainly interstitial characterized by lymphoplasmocytic infiltrate and several spots of necrosis like Zencker degeneration. Based on histologic criteria, our data suggest that: the main determinant of muscle weakness seen in chronic alcoholic patients is neurogenic in origin (alcoholic polineuropathy; the direct toxic action of ethanol under the skeletal muscle is closely related to the mitochondrial metabolism; the so-called acute alcoholic myopathy has probably viral etiology.

  18. Artificial muscle: facts and fiction.

    Science.gov (United States)

    Schaub, Marcus C

    2011-12-19

    Mechanical devices are sought to support insufficient or paralysed striated muscles including the failing heart. Nickel-titanium alloys (nitinol) present the following two properties: (i) super-elasticity, and (ii) the potential to assume different crystal structures depending on temperature and/or stress. Starting from the martensite state nitinol is able to resume the austenite form (state of low potential energy and high entropy) even against an external resistance. This one-way shape change is deployed in self-expanding vascular stents. Heating induces the force generating transformation from martensite to the austenite state while cooling induces relaxation back to the martensite state. This two-way shape change oscillating between the two states may be used in cyclically contracting support devices of silicon-coated nitinol wires. Such a contractile device sutured to the right atrium has been tested in vitro in a bench model and in vivo in sheep. The contraction properties of natural muscles, specifically of the myocardium, and the tight correlation with ATP production by oxidative phosphorylation in the mitochondria is briefly outlined. Force development by the nitinol device cannot be smoothly regulated as in natural muscle. Its mechanical impact is forced onto the natural muscle regardless of the actual condition with regard to metabolism and Ca2+-homeostasis. The development of artificial muscle on the basis of nitinol wires is still in its infancy. The nitinol artificial muscle will have to prove its viability in the various clinical settings.

  19. Satellite cells: the architects of skeletal muscle.

    Science.gov (United States)

    Chang, Natasha C; Rudnicki, Michael A

    2014-01-01

    The outstanding regenerative capacity of skeletal muscle is attributed to the resident muscle stem cell termed satellite cell. Satellite cells are essential for skeletal muscle regeneration as they ultimately provide the myogenic precursors that rebuild damaged muscle tissue. Satellite cells characteristically are a heterogeneous population of stem cells and committed progenitor cells. Delineation of cellular hierarchy and understanding how lineage fate choices are determined within the satellite cell population will be invaluable for the advancement of muscle regenerative therapies.

  20. Simple technique for maximal thoracic muscle harvest.

    Science.gov (United States)

    Marshall, M Blair; Kaiser, Larry R; Kucharczuk, John C

    2004-04-01

    We present a modification of technique for standard muscle flap harvest, the placement of cutaneous traction sutures. This technique allows for maximal dissection of the thoracic muscles even through minimal incisions. Through improved exposure and traction, complete dissection of the muscle bed can be performed and the tissue obtained maximized. Because more muscle bulk is obtained with this technique, the need for a second muscle may be prevented.

  1. Effect of acupuncture depth on muscle pain

    Directory of Open Access Journals (Sweden)

    Kitakoji Hiroshi

    2011-06-01

    Full Text Available Abstract Background While evidence supports efficacy of acupuncture and/or dry needling in treating musculoskeletal pain, it is unclear which needling method is most effective. This study aims to determine the effects of depth of needle penetration on muscle pain. Methods A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle, muscle group (depth of 10 mm: the extensor digital muscle and non-segmental group (depth of 10 mm: the anterior tibial muscle. Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise. Results Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle and muscle group (depth of 10 mm: the extensor digital muscle were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle was a significantly higher than control group; however, there was no significant difference between the control and other groups. Conclusion The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain.

  2. A comparative study of the modified Sauvé-Kapandji procedure for rheumatoid wrist with and without stabilization of the proximal ulnar stump.

    Science.gov (United States)

    Kawabata, A; Egi, T; Hashimoto, H; Masada, K; Saito, S

    2010-10-01

    We compared the clinical and radiological results of the modified Sauvé-Kapandji procedure for 41 of 86 operated rheumatoid wrists with (n=22) and without (n=19) stabilization of the proximal ulnar stump with a slip of half the extensor carpi ulnaris tendon. Gender, age, and follow-up period were similar in the two groups. We found no difference clinically or on radiographs between the two groups other than better early postoperative pain relief in those stabilized. Stabilization of the proximal ulnar stump may not be necessary in the modified Sauvé-Kapandji procedure for rheumatoid wrists.

  3. MR Imaging and US of the Wrist Tendons.

    Science.gov (United States)

    Plotkin, Benjamin; Sampath, Srihari C; Sampath, Srinath C; Motamedi, Kambiz

    2016-10-01

    The tendons of the wrist are commonly symptomatic. They can be injured, infected, or inflamed. Magnetic resonance imaging and ultrasonography are useful tools for evaluating the wrist. Pathologic conditions of the wrist tendons include de Quervain tenosynovitis, extensor carpi ulnaris tendinopathy, rheumatoid tenosynovitis, infectious synovitis, tendon tears, hydroxyapatite deposition disease, intersection syndrome, tenosynovial giant cell tumor, and fibroma of the tendon sheath. In this article, we review the normal appearance of the wrist tendons, discuss relevant anatomy, and give an overview of common pathologic conditions affecting the wrist tendons. Online supplemental material is available for this article. (©)RSNA, 2016.

  4. Laughing: a demanding exercise for trunk muscles.

    Science.gov (United States)

    Wagner, Heiko; Rehmes, Ulrich; Kohle, Daniel; Puta, Christian

    2014-01-01

    Social, psychological, and physiological studies have provided evidence indicating that laughter imposes an increased demand on trunk muscles. It was the aim of this study to quantify the activation of trunk muscles during laughter yoga in comparison with crunch and back lifting exercises regarding the mean trunk muscle activity. Muscular activity during laughter yoga exercises was measured by surface electromyography of 5 trunk muscles. The activation level of internal oblique muscle during laughter yoga is higher compared to the traditional exercises. The multifidus, erector spinae, and rectus abdominis muscles were nearly half activated during laughter yoga, while the activation of the external oblique muscle was comparable with the crunch and back lifting exercises. Our results indicate that laughter yoga has a positive effect on trunk muscle activation. Thus, laughter seems to be a good activator of trunk muscles, but further research is required whether laughter yoga is a good exercise to improve neuromuscular recruitment patterns for spine stability.

  5. Muscle pathology in juvenile dermatomyositis

    Directory of Open Access Journals (Sweden)

    Edenilson Eduardo Calore

    Full Text Available OBJECTIVE: To study muscle biopsies, using histochemistry, on ten children with infantile dermatomyositis. DESIGN: Series of ten patients (of whom eight patients had received treatment and two had not were submitted to muscle biopsy in order to diagnose possible inflammatory myopathy or to detect recurrences. PLACE OF DEVELOPMENT OF THE STUDY: Public Health Service of São Paulo State. PARTICIPANTS: children with clinical features of inflammatory myopathy. INTERVENTION: biopsies were performed on the vastus lateralis using local anesthetic. Histochemistry was performed according to standardized methods. RESULTS: Architectural changes of the muscle fibers, necrosis of variable intensity and accentuated evidence of regeneration were observed in patients who had not received treatment (2 cases and in one case where muscular weakness persisted in spite of corticosteroid therapy. Necrosis and regeneration were minimal or absent in cases treated for one year or more (4 cases. In 3 cases with clinical and laboratorial recurrences, muscle necrosis and architectural changes were detected. CONCLUSIONS: It was concluded that muscle biopsy could aid in diagnosing infantile dermatomyositis as well as in detecting recurrences even in cases without clinical activity of the disease.

  6. Laser therapy of muscle injuries.

    Science.gov (United States)

    Dawood, Munqith S; Al-Salihi, Anam Rasheed; Qasim, Amenah Wala'a

    2013-05-01

    Low-level lasers are used in general therapy and healing process due to their good photo-bio-stimulation effects. In this paper, the effects of diode laser and Nd:YAG laser on the healing process of practically managed skeletal muscle trauma has been successfully studied. Standard impact trauma was induced by using a specially designed mechanical device. The impacted muscle was left for 3 days for complete development of blunt trauma. After that it was irradiated by five laser sessions for 5 days. Two types of lasers were used; 785-nm diode laser and 1.064-nm Nd:YAG laser, both in continuous and pulsed modes. A special electronic circuit was designed and implemented to modulate the diode laser for this purpose. Tissue samples of crushed skeletal muscle have been dissected from the injured irradiated muscle then bio-chemically analyzed for the regeneration of contractile and collagenous proteins using Lowry assay for protein determination and Reddy and Enwemeka assay for hydroxyproline determination. The results showed that both lasers stimulate the regeneration capability of traumatized skeletal muscle. The diode laser in CW and pulsed modes showed better results than the Nd:YAG in accelerating the preservation of the normal tissue content of collagenous and contractile proteins beside controlling the regeneration of non-functional fibrous tissue. This study proved that the healing achieved by the laser treatment was faster than the control group by 15-20 days.

  7. Choosing a skeletal muscle relaxant.

    Science.gov (United States)

    See, Sharon; Ginzburg, Regina

    2008-08-01

    Skeletal muscle relaxants are widely used in treating musculoskeletal conditions. However, evidence of their effectiveness consists mainly of studies with poor methodologic design. In addition, these drugs have not been proven to be superior to acetaminophen or nonsteroidal anti-inflammatory drugs for low back pain. Systematic reviews and meta-analyses support using skeletal muscle relaxants for short-term relief of acute low back pain when nonsteroidal anti-inflammatory drugs or acetaminophen are not effective or tolerated. Comparison studies have not shown one skeletal muscle relaxant to be superior to another. Cyclobenzaprine is the most heavily studied and has been shown to be effective for various musculoskeletal conditions. The sedative properties of tizanidine and cyclobenzaprine may benefit patients with insomnia caused by severe muscle spasms. Methocarbamol and metaxalone are less sedating, although effectiveness evidence is limited. Adverse effects, particularly dizziness and drowsiness, are consistently reported with all skeletal muscle relaxants. The potential adverse effects should be communicated clearly to the patient. Because of limited comparable effectiveness data, choice of agent should be based on side-effect profile, patient preference, abuse potential, and possible drug interactions.

  8. Continuous Estimation of Wrist Torque from Surface EMG Signals Using Path-dependent Model

    Institute of Scientific and Technical Information of China (English)

    PAN Li-zhi; ZHANG Ding-guo; SHENG Xin-jun; ZHU Xiang-yang

    2014-01-01

    Continuous estimation of wrist torque from surface electromyography (EMG) signals has been studied by some research institutes. Hysteresis effect is a phenomenon in EMG force relationship. In this work, a path-dependent model based on hysteresis effect was used for continuously estimating wrist torque from surface EMG signals. The surface EMG signals of the flexor carpi ulnaris (FCU) and extensor carpi radialis (ECR) were collected along with wrist torque of flexion/extension degree-of-freedom. EMG signal of FCU was used to estimate the torque of wrist flexion and EMG signal of ECR to estimate the torque of wrist extension. The existence of hysteresis effect has been proven either during wrist flexion or extension on all subjects. And the estimation performance of path-dependent model is much better than the overall model. Thus, the path-dependent model is suitable to improve the wrist torque's estimation accuracy.

  9. CORRELATIONS BETWEEN MUSCLE MASS, MUSCLE STRENGTH, PHYSICAL PERFORMANCE, AND MUSCLE FATIGUE RESISTANCE IN COMMUNITY-DWELLING ELDERLY SUBJECTS

    Directory of Open Access Journals (Sweden)

    Elizabeth

    2016-03-01

    Full Text Available Objective: To determine the correlations between muscle mass, muscle strength, physical performance, and muscle fatigue resistance in community-dwelling elderly people in order to elucidate factors which contribute to elderly’s performance of daily activities. Methods: A cross-sectional study was conducted on community-dwelling elderly in Bandung from September to December 2014. One hundred and thirty elderly, 60 years old or above, were evaluated using bioelectrical impedance analysis to measure muscle mass; grip strength to measure muscle strength and muscle fatigue resistance; habitual gait speed to measure physical performance; and Global Physical Activity Questionnaire (GPAQ to assess physical activity. Results: There were significant positive correlations between muscle mass (r=0,27, p=0,0019, muscle strength (r=0,26, p=0,0024, and physical performance (r=0,32, p=0,0002 with muscle fatigue resistance. Physical performance has the highest correlation based on multiple regression test (p=0,0025. In association with muscle mass, the physical activity showed a significant positive correlation (r=0,42, p=0,0000. Sarcopenia was identified in 19 (14.61% of 130 subjects. Conclusions: It is suggested that muscle mass, muscle strength, and physical performance influence muscle fatigue resistance.

  10. Therapeutic effects of massage and electrotherapy on muscle tone, stiffness and muscle contraction following gastrocnemius muscle fatigue

    Science.gov (United States)

    Wang, Joong-San

    2017-01-01

    [Purpose] This study aimed to examine the effects of a combined intervention consisting of massage therapy and transcutaneous electrical nerve stimulation on gastrocnemius muscle fatigue, assessing whether the intervention improved muscle tone, stiffness, and muscle contraction. [Subjects and Methods] The subjects were 20 healthy males in their 20s who were equally divided into a transcutaneous electrical nerve stimulation group and a combined therapy group that received a combination of massage therapy and transcutaneous electrical nerve stimulation. Muscle fatigue was triggered on the gastrocnemius muscle, and the effects of intervention method on muscle tone, stiffness, and muscle contraction were examined over time. [Results] Lateral and medial gastrocnemius muscle tone and stiffness significantly increased and gastrocnemius muscle contraction significantly decreased in each group immediately after fatigue was triggered on the gastrocnemius muscle. There was no difference in the effects of the two intervention methods over time. [Conclusion] This study verified that a combined therapy of massage therapy and transcutaneous electrical nerve stimulation was able to be used effectively in improving muscle tone, stiffness, muscle contraction, thereby reducing gastrocnemius muscle fatigue. PMID:28210061

  11. Pelvic floor muscle rehabilitation using biofeedback.

    Science.gov (United States)

    Newman, Diane K

    2014-01-01

    Pelvic floor muscle exercises have been recommended for urinary incontinence since first described by obstetrician gynecologist Dr. Arnold Kegel more than six decades ago. These exercises are performed to strengthen pelvic floor muscles, provide urethral support to prevent urine leakage, and suppress urgency. In clinical urology practice, expert clinicians also teach patients how to relax the muscle to improve bladder emptying and relieve pelvic pain caused by muscle spasm. When treating lower urinary tract symptoms, an exercise training program combined with biofeedback therapy has been recommended as first-line treatment. This article provides clinical application of pelvic floor muscle rehabilitation using biofeedback as a technique to enhance pelvic floor muscle training.

  12. Muscle after spinal cord injury

    DEFF Research Database (Denmark)

    Biering-Sørensen, Bo; Kristensen, Ida Bruun; Kjaer, Michael;

    2009-01-01

    The morphological and contractile changes of muscles below the level of the lesion after spinal cord injury (SCI) are dramatic. In humans with SCI, a fiber-type transformation away from type I begins 4-7 months post-SCI and reaches a new steady state with predominantly fast glycolytic IIX fibers...... years after the injury. There is a progressive drop in the proportion of slow myosin heavy chain (MHC) isoform fibers and a rise in the proportion of fibers that coexpress both the fast and slow MHC isoforms. The oxidative enzymatic activity starts to decline after the first few months post-SCI. Muscles...... from individuals with chronic SCI show less resistance to fatigue, and the speed-related contractile properties change, becoming faster. These findings are also present in animals. Future studies should longitudinally examine changes in muscles from early SCI until steady state is reached in order...

  13. Torsional Carbon Nanotube Artificial Muscles

    Science.gov (United States)

    Foroughi, Javad; Spinks, Geoffrey M.; Wallace, Gordon G.; Oh, Jiyoung; Kozlov, Mikhail E.; Fang, Shaoli; Mirfakhrai, Tissaphern; Madden, John D. W.; Shin, Min Kyoon; Kim, Seon Jeong; Baughman, Ray H.

    2011-10-01

    Rotary motors of conventional design can be rather complex and are therefore difficult to miniaturize; previous carbon nanotube artificial muscles provide contraction and bending, but not rotation. We show that an electrolyte-filled twist-spun carbon nanotube yarn, much thinner than a human hair, functions as a torsional artificial muscle in a simple three-electrode electrochemical system, providing a reversible 15,000° rotation and 590 revolutions per minute. A hydrostatic actuation mechanism, as seen in muscular hydrostats in nature, explains the simultaneous occurrence of lengthwise contraction and torsional rotation during the yarn volume increase caused by electrochemical double-layer charge injection. The use of a torsional yarn muscle as a mixer for a fluidic chip is demonstrated.

  14. Repositioning forelimb superficialis muscles: tendon attachment and muscle activity enable active relocation of functional myofibers.

    Science.gov (United States)

    Huang, Alice H; Riordan, Timothy J; Wang, Lingyan; Eyal, Shai; Zelzer, Elazar; Brigande, John V; Schweitzer, Ronen

    2013-09-16

    The muscles that govern hand motion are composed of extrinsic muscles that reside within the forearm and intrinsic muscles that reside within the hand. We find that the extrinsic muscles of the flexor digitorum superficialis (FDS) first differentiate as intrinsic muscles within the hand and then relocate as myofibers to their final position in the arm. This remarkable translocation of differentiated myofibers across a joint is dependent on muscle contraction and muscle-tendon attachment. Interestingly, the intrinsic flexor digitorum brevis (FDB) muscles of the foot are identical to the FDS in tendon pattern and delayed developmental timing but undergo limited muscle translocation, providing strong support for evolutionary homology between the FDS and FDB muscles. We propose that the intrinsic FDB pattern represents the original tetrapod limb and that translocation of the muscles to form the FDS is a mammalian evolutionary addition.

  15. Relationship of Skeletal Muscle Development and Growth to Breast Muscle Myopathies: A Review.

    Science.gov (United States)

    Velleman, Sandra G

    2015-12-01

    Selection in meat-type birds has focused on growth rate, muscling, and feed conversion. These strategies have made substantial improvements but have affected muscle structure, repair mechanisms, and meat quality, especially in the breast muscle. The increase in muscle fiber diameters has reduced available connective tissue spacing, reduced blood supply, and altered muscle metabolism in the breast muscle. These changes have increased muscle fiber degeneration and necrosis but have limited muscle repair mechanisms mediated by the adult myoblast (satellite cell) population of cells, likely resulting in the onset of myopathies. This review focuses on muscle growth mechanisms and how changes in the cellular development of the breast muscle may be associated with breast muscle myopathies occurring in meat-type birds.

  16. Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients

    DEFF Research Database (Denmark)

    Suetta, Charlotte; Andersen, Jesper L; Dalgas, Ulrik;

    2008-01-01

    beneficial qualitative changes in muscle fiber morphology and muscle architecture in elderly postoperative patients. In contrast, rehabilitation regimes based on functional exercises and neuromuscular electrical stimulation had no effect. The present data emphasize the importance of resistance training...

  17. Spontaneous waves in muscle fibres

    Science.gov (United States)

    Günther, Stefan; Kruse, Karsten

    2007-11-01

    Mechanical oscillations are important for many cellular processes, e.g. the beating of cilia and flagella or the sensation of sound by hair cells. These dynamic states originate from spontaneous oscillations of molecular motors. A particularly clear example of such oscillations has been observed in muscle fibers under non-physiological conditions. In that case, motor oscillations lead to contraction waves along the fiber. By a macroscopic analysis of muscle fiber dynamics we find that the spontaneous waves involve non-hydrodynamic modes. A simple microscopic model of sarcomere dynamics highlights mechanical aspects of the motor dynamics and fits with the experimental observations.

  18. Muscle phosphoglycerate mutase deficiency revisited

    DEFF Research Database (Denmark)

    Naini, Ali; Toscano, Antonio; Musumeci, Olimpia;

    2009-01-01

    storage disease type X and novel mutations in the gene encoding the muscle subunit of PGAM (PGAM2). DESIGN: Clinical, pathological, biochemical, and molecular analyses. SETTING: Tertiary care university hospitals and academic institutions. Patients A 37-year-old Danish man of Pakistani origin who had...... PGAM deficiency, and molecular studies revealed 2 novel homozygous mutations, a nonsense mutation and a single nucleotide deletion. Pathological studies of muscle showed mild glycogen accumulation but prominent tubular aggregates in both patients. CONCLUSIONS: We found that glycogen storage disease...

  19. No Muscle Is an Island

    DEFF Research Database (Denmark)

    Kent, Jane A; Ørtenblad, Niels; Hogan, Michael C;

    2016-01-01

    Muscle fatigue has been studied with a variety approaches, tools and technologies. The foci of these studies have ranged tremendously, from molecules to the entire organism. Single cell and animal models have been used to gain mechanistic insight into the fatigue process. The theme of this review...... is the concept that the mechanisms of muscle fatigue do not occur in isolation in vivo: muscular work is supported by many complex physiological systems, any of which could fail during exercise and thus contribute to fatigue. To advance our overall understanding of fatigue, a combination of models and approaches...

  20. Muscle GLUT4 in cirrhosis

    DEFF Research Database (Denmark)

    Holland-Fischer, Peter; Andersen, Per Heden; Lund, Sten

    2007-01-01

    test and later a muscle biopsy. Levels of GLUT4 total protein and mRNA content were determined in muscle biopsies by polyclonal antibody labelling and RT-PCR, respectively. RESULTS: GLUT4 protein content in the cirrhosis group was not different from that of the controls, but at variance......: In cirrhosis GLUT4 protein content was quantitatively intact, while limiting glucose tolerance. This indicates loss of redundancy of the major glucose transport system, possibly related to the markedly decreased expression of its gene. Hyper-insulinemia may be a primary event. Our findings implicate...

  1. Muscle cramps in liver disease.

    Science.gov (United States)

    Mehta, Shivang S; Fallon, Michael B

    2013-11-01

    Muscle cramps are common in patients with liver disease and adversely influence quality of life. The exact mechanisms by which they occur remain unclear, although a number of pathophysiological events unique to liver disease may contribute. Clinical studies have identified alterations in 3 areas: nerve function, energy metabolism, and plasma volume/electrolytes. Treatments have focused on these particular areas with varied results. This review will focus on the clinical features of muscle cramps in patients with liver disease and review potential mechanisms and current therapies.

  2. Changes in muscle spindle firing in response to length changes of neighboring muscles.

    Science.gov (United States)

    Smilde, Hiltsje A; Vincent, Jake A; Baan, Guus C; Nardelli, Paul; Lodder, Johannes C; Mansvelder, Huibert D; Cope, Tim C; Maas, Huub

    2016-06-01

    Skeletal muscle force can be transmitted to the skeleton, not only via its tendons of origin and insertion but also through connective tissues linking the muscle belly to surrounding structures. Through such epimuscular myofascial connections, length changes of a muscle may cause length changes within an adjacent muscle and hence, affect muscle spindles. The aim of the present study was to investigate the effects of epimuscular myofascial forces on feedback from muscle spindles in triceps surae muscles of the rat. We hypothesized that within an intact muscle compartment, muscle spindles not only signal length changes of the muscle in which they are located but can also sense length changes that occur as a result of changing the length of synergistic muscles. Action potentials from single afferents were measured intra-axonally in response to ramp-hold release (RHR) stretches of an agonistic muscle at different lengths of its synergist, as well as in response to synergist RHRs. A decrease in force threshold was found for both soleus (SO) and lateral gastrocnemius afferents, along with an increase in length threshold for SO afferents. In addition, muscle spindle firing could be evoked by RHRs of the synergistic muscle. We conclude that muscle spindles not only signal length changes of the muscle in which they are located but also local length changes that occur as a result of changing the length and relative position of synergistic muscles.

  3. PLASTICITY OF SKELETAL MUSCLE STUDIED BY STEREOLOGY

    Directory of Open Access Journals (Sweden)

    Ida Eržen

    2011-05-01

    Full Text Available The present contribution provides an overview of stereological methods applied in the skeletal muscle research at the Institute of Anatomy of the Medical Faculty in Ljubljana. Interested in skeletal muscle plasticity we studied three different topics: (i expression of myosin heavy chain isoforms in slow and fast muscles under experimental conditions, (ii frequency of satellite cells in young and old human and rat muscles and (iii capillary supply of rat fast and slow muscles. We analysed the expression of myosin heavy chain isoforms within slow rat soleus and fast extensor digitorum longus muscles after (i homotopic and heterotopic transplantation of both muscles, (ii low frequency electrical stimulation of the fast muscle and (iii transposition of the fast nerve to the slow muscle. The models applied were able to turn the fast muscle into a completely slow muscle, but not vice versa. One of the indicators for the regenerative potential of skeletal muscles is its satellite cell pool. The estimated parameters, number of satellite cells per unit fibre length, corrected to the reference sarcomere length (Nsc/Lfib and number of satellite cells per number of nuclei (myonuclei and satellite cell nuclei (Nsc/Nnucl indicated that the frequency of M-cadherin stained satellite cells declines in healthy old human and rat muscles compared to young muscles. To access differences in capillary densities among slow and fast muscles and slow and fast muscle fibres, we have introduced Slicer and Fakir methods, and tested them on predominantly slow and fast rat muscles. Discussing three different topics that require different approach, the present paper reflects the three decades of the development of stereological methods: 2D analysis by simple point counting in the 70's, the disector in the 80's and virtual spatial probes in the 90's. In all methods the interactive computer assisted approach was utilised.

  4. Myofascial force transmission between antagonistic rat lower limb muscles: Effects of single muscle or muscle group lengthening

    NARCIS (Netherlands)

    Meijer, Hanneke J.M; Rijkelijkhuizen, Josina M.; Huijing, Peter A.

    2007-01-01

    Effects of lengthening of the whole group of anterior crural muscles (tibialis anterior and extensor hallucis longus muscles (TA + EHL) and extensor digitorum longus (EDL)) on myofascial interaction between synergistic EDL and TA + EHL muscles, and on myofascial force transmission between anterior c

  5. Muscle force recovery in relation to muscle oxygenation.

    Science.gov (United States)

    Ufland, Pierre; Lapole, Thomas; Ahmaidi, Said; Buchheit, Martin

    2012-09-01

    The aim of this study was to investigate the relative contribution of human muscle reoxygenation on force recovery following a maximal voluntary contraction (MVC). Ten athletes (22·9 ± 4·0 years) executed a plantar-flexion sequence including two repeated MVCs [i.e. a 30-s MVC (MVC(30)) followed by a 10-s MVC (MVC(10))] separated by 10, 30, 60, 120 or 300 s of passive recovery. A 10-min passive recovery period was allowed between each MVC sequence. This procedure was randomly repeated with two different recovery conditions: without (CON) or with (OCC) arterial occlusion of the medial gastrocnemius. During OCC, the occlusion was maintained from the end of MVC(30) to the end of MVC(10). Muscle oxygenation (Near-infrared spectroscopy, NIRS, [Hb(diff) ]) was continuously measured during all MVC sequences and expressed as a percentage of the maximal changes in optical density observed during MVC(30). Maximal Torque was analysed at the start of each contraction. Torque during each MVC(10) was expressed as a percentage of the Torque during the previous MVC(30). Torque recovery was complete within 300 s after MVC(30) during CON (MVC(10) = 101·8 ± 5·0%); 88·6 ± 8·9% of the Torque was recovered during OCC (P = 0·005). There was also a moderate correlation between absolute level of muscle oxygenation and Torque (r = 0·32 (90% CI, 0·09;0·52), P = 0·02). Present findings confirm the role of human muscle oxygenation in muscular force recovery during repeated-maximal efforts. However, the correlation between absolute muscle oxygenation and force level during recovery is only moderate, suggesting that other mechanisms are likely involved in the force recovery process.

  6. Force time-history affects fatigue accumulation during repetitive handgrip tasks.

    Science.gov (United States)

    Sonne, Michael W; Hodder, Joanne N; Wells, Ryan; Potvin, Jim R

    2015-02-01

    Muscle fatigue is associated with a higher risk of workplace injury, in particular during repetitive tasks. This study aimed to identify the effect of a complex force-time history (a task with multiple different submaximal effort levels) on fatigue accumulation and recovery during a handgrip task. We measured surface electromyography of the brachioradialis (BRD) and flexor carpi ulnaris (FCU) of ten right hand dominant females with no history of upper limb injury while they performed a complex submaximal visually targeted gripping task. The task consisted of 15%, 30%, 45%, 30%, and 15% maximum voluntary contraction (MVC) plateaus. Each plateau was held for 15s, followed by a 3s MVC and 3s of rest. The "pyramid" was repeated until fatigue criteria were met. Grip force, average EMG and mean power frequency (MnPF) for first cycle and fatigued last cycle, were compared. Post-plateau peak grip force was on average 20.5% MVC lower during the last cycle (pMVC after the first 15% MVC plateau (from baseline), by 5.3% MVC after the 30% MVC plateau and 6.8% MVC after the 45% MVC plateau. Further accumulation of fatigue after the second 30% MVC plateau however was minimal, only decreasing by 1.6% MVC. Recovery appeared to occur during the last 15% MVC plateau with an increase in post plateau grip force of 1.6% MVC. Interestingly, MnPF parameters confirmed significant fatigue accumulation during the back end of a force pyramid. We conclude that in a pattern of contractions with ascending, then descending force intensity, voluntary force recovery was present when the preceding force was of a lower intensity. These findings indicate preceding demands play a role in fatigue accumulation during complex tasks.

  7. Exercise-Induced Skeletal Muscle Damage.

    Science.gov (United States)

    Evans, William J.

    1987-01-01

    Eccentric exercise, in which the muscles exert force by lengthening, is associated with delayed onset muscle soreness. How soreness occurs, how recovery proceeds, and what precautions athletes should take are described. (Author/MT)

  8. Pharmacology of airway smooth muscle proliferation

    NARCIS (Netherlands)

    Gosens, Reinoud; Roscioni, Sara S.; Dekkers, Bart G. J.; Pera, Tonio; Schmidt, Martina; Schaafsma, Dedmer; Zaagsma, Johan; Meurs, Herman

    2008-01-01

    Airway smooth muscle thickening is a pathological feature that contributes significantly to airflow limitation and airway hyperresponsiveness in asthma. Ongoing research efforts aimed at identifying the mechanisms responsible for the increased airway smooth muscle mass have indicated that hyperplasi

  9. Scientists Create Clothing with 'Knitted' Muscle Power

    Science.gov (United States)

    ... 163272.html Scientists Create Clothing With 'Knitted' Muscle Power Fabric reacts to low voltage charge and could ... techniques that one day might help provide muscle power to disabled people or seniors who have trouble ...

  10. Magnetic resonance imaging of facial muscles

    Energy Technology Data Exchange (ETDEWEB)

    Farrugia, M.E. [Department of Clinical Neurology, University of Oxford, Radcliffe Infirmary, Oxford (United Kingdom)], E-mail: m.e.farrugia@doctors.org.uk; Bydder, G.M. [Department of Radiology, University of California, San Diego, CA 92103-8226 (United States); Francis, J.M.; Robson, M.D. [OCMR, Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford (United Kingdom)

    2007-11-15

    Facial and tongue muscles are commonly involved in patients with neuromuscular disorders. However, these muscles are not as easily accessible for biopsy and pathological examination as limb muscles. We have previously investigated myasthenia gravis patients with MuSK antibodies for facial and tongue muscle atrophy using different magnetic resonance imaging sequences, including ultrashort echo time techniques and image analysis tools that allowed us to obtain quantitative assessments of facial muscles. This imaging study had shown that facial muscle measurement is possible and that useful information can be obtained using a quantitative approach. In this paper we aim to review in detail the methods that we applied to our study, to enable clinicians to study these muscles within the domain of neuromuscular disease, oncological or head and neck specialties. Quantitative assessment of the facial musculature may be of value in improving the understanding of pathological processes occurring within facial muscles in certain neuromuscular disorders.

  11. Study on distribution of terminal branches of the facial nerve in mimetic muscles (orbicularis oculi muscle and orbicularis oris muscle).

    Science.gov (United States)

    Mitsukawa, Nobuyuki; Moriyama, Hiroshi; Shiozawa, Kei; Satoh, Kaneshige

    2014-01-01

    There have been many anatomical reports to date regarding the course of the facial nerve to the mimetic muscles. However, reports are relatively scarce on the detailed distribution of the terminal branches of the facial nerve to the mimetic muscles. In this study, we performed detailed examination of the terminal facial nerve branches to the mimetic muscles, particularly the branches terminating in the orbicularis oculi muscle and orbicularis oris muscle. Examination was performed on 25 Japanese adult autopsy cases, involving 25 hemifaces. The mean age was 87.4 years (range, 60-102 years). There were 12 men and 13 women (12 left hemifaces and 13 right hemifaces). In each case, the facial nerve was exposed through a preauricular skin incision. The main trunk of the facial nerve was dissected from the stylomastoid foramen. A microscope was used to dissect the terminal branches to the periphery and observe them. The course and distribution were examined for all terminal branches of the facial nerve. However, focus was placed on the course and distribution of the zygomatic branch, buccal branch, and mandibular branch to the orbicularis oculi muscle and orbicularis oris muscle. The temporal branch was distributed to the orbicularis oculi muscle in all cases and the marginal mandibular branch was distributed to the orbicularis oris muscle in all cases. The zygomatic branch was distributed to the orbicularis oculi muscle in all cases, but it was also distributed to the orbicularis oris muscle in 10 of 25 cases. The buccal branch was not distributed to the orbicularis oris muscle in 3 of 25 cases, and it was distributed to the orbicularis oculi muscle in 8 cases. There was no significant difference in the variations. The orbicularis oculi muscle and orbicularis oris muscle perform particularly important movements among the facial mimetic muscles. According to textbooks, the temporal branch and zygomatic branch innervate the orbicularis oculi muscle, and the buccal branch

  12. Intrafusal muscle fibre types in frog spindles.

    Science.gov (United States)

    Diwan, F H; Ito, F

    1989-04-01

    Muscle spindles from bullfrog semitendinosus, iliofibularis and sartorius muscles were examined with light and electron microscopy. Four types of intrafusal muscle fibre were identified according to their diameter, central nucleation and reticular zone arrangement: a large nuclear bag fibre, a medium nuclear bag fibre, and two types of small nuclear chain fibres with and without a reticular zone, respectively. It is suggested that they are comparable to the nuclear bag1, bag2 and chain fibres in mammalian muscle spindles.

  13. Mechanisms of exertional fatigue in muscle glycogenoses

    DEFF Research Database (Denmark)

    Vissing, John; Haller, Ronald G

    2012-01-01

    concentrations of extracellular potassium in exercising muscle and (3) exaggerated accumulation of ADP during exercise that may inhibit sodium-potassium and calcium-ATPases. Disorders of muscle glycogenolysis and glycolysis reveal the crucial role of these metabolic processes for supplying both anaerobic...... and aerobic energy for muscle contraction; and the pathological fatigue that occurs when glycogenolysis and/or glycolysis is blocked imply an important role for theses metabolic pathways in normal muscle fatigue....

  14. Exercise Promotes Healthy Aging of Skeletal Muscle

    DEFF Research Database (Denmark)

    Cartee, Gregory D; Hepple, Russell T; Bamman, Marcas M

    2016-01-01

    caused by diseases and lifestyle factors. Secondary aging can exacerbate deficits in mitochondrial function and muscle mass, concomitant with the development of skeletal muscle insulin resistance. Exercise opposes deleterious effects of secondary aging by preventing the decline in mitochondrial...... respiration, mitigating aging-related loss of muscle mass and enhancing insulin sensitivity. This review focuses on mechanisms by which exercise promotes "healthy aging" by inducing modifications in skeletal muscle....

  15. Mitochondrial signaling contributes to disuse muscle atrophy

    OpenAIRE

    Powers, Scott K.; Wiggs, Michael P.; Duarte, Jose A.; Zergeroglu, A. Murat; Demirel, Haydar A.

    2012-01-01

    It is well established that long durations of bed rest, limb immobilization, or reduced activity in respiratory muscles during mechanical ventilation results in skeletal muscle atrophy in humans and other animals. The idea that mitochondrial damage/dysfunction contributes to disuse muscle atrophy originated over 40 years ago. These early studies were largely descriptive and did not provide unequivocal evidence that mitochondria play a primary role in disuse muscle atrophy. However, recent exp...

  16. Muscle mechanics and neuromuscular control

    NARCIS (Netherlands)

    Hof, AL

    2003-01-01

    The purpose of this paper is to demonstrate that the properties of the mechanical system, especially muscle elasticity and limb mass, to a large degree determine force output and movement. This makes the control demands of the central nervous system simpler and more robust. In human triceps surae, a

  17. [Antisynthetase syndrome without muscle involvement].

    Science.gov (United States)

    Júdez Navarro, Enrique; Martínez Carretero, Myriam; Martínez Jiménez, Gonzalo Fidel

    2007-11-01

    Antisynthetase syndrome is a well defined syndrome characterized by the presence of interstitial lung disease in association with arthritis, miositis, mechanic's hands and Ruynaud's phenomenon in the presence of antisynthetase antibodies, especially Ac anti-Jo1. We described the case of a 68-year-old man with this syndrome in the absence of inflammatory muscle disease.

  18. Novel Analog For Muscle Deconditioning

    Science.gov (United States)

    Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd. Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Ploutz-Snyder, Robert; Bloomberg, Jacob

    2011-01-01

    Existing models (such as bed rest) of muscle deconditioning are cumbersome and expensive. We propose a new model utilizing a weighted suit to manipulate strength, power, or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre-and postflightastronaut performance data for the same tasks. Splineregression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/BW of 79 J/kg, isokineticknee extension (KE)/BW of 6 Nm/kg, and KE torque/BW of 1.9 Nm/kg.Conclusions: Laboratory manipulation of relative strength has promise as an appropriate analog for spaceflight-induced loss of muscle function, for predicting occupational task performance and establishing operationally relevant strength thresholds.

  19. Metabolic Adaptation to Muscle Ischemia

    Science.gov (United States)

    Cabrera, Marco E.; Coon, Jennifer E.; Kalhan, Satish C.; Radhakrishnan, Krishnan; Saidel, Gerald M.; Stanley, William C.

    2000-01-01

    Although all tissues in the body can adapt to varying physiological/pathological conditions, muscle is the most adaptable. To understand the significance of cellular events and their role in controlling metabolic adaptations in complex physiological systems, it is necessary to link cellular and system levels by means of mechanistic computational models. The main objective of this work is to improve understanding of the regulation of energy metabolism during skeletal/cardiac muscle ischemia by combining in vivo experiments and quantitative models of metabolism. Our main focus is to investigate factors affecting lactate metabolism (e.g., NADH/NAD) and the inter-regulation between carbohydrate and fatty acid metabolism during a reduction in regional blood flow. A mechanistic mathematical model of energy metabolism has been developed to link cellular metabolic processes and their control mechanisms to tissue (skeletal muscle) and organ (heart) physiological responses. We applied this model to simulate the relationship between tissue oxygenation, redox state, and lactate metabolism in skeletal muscle. The model was validated using human data from published occlusion studies. Currently, we are investigating the difference in the responses to sudden vs. gradual onset ischemia in swine by combining in vivo experimental studies with computational models of myocardial energy metabolism during normal and ischemic conditions.

  20. Classification of the intrafusal muscle fibres in the frog muscle spindle: histochemical and immunofluorescent studies.

    OpenAIRE

    Yoshimura, A; Fujitsuka, N; Sokabe, M; Naruse, K; Nomura, K; Diwan, F H; Ito, F

    1990-01-01

    Intrafusal muscle fibres from bull-frog semitendinosus, iliofibularis and sartorius muscles were classified into three types using the histochemical, immunofluorescent and morphological characteristics, with reference to the extrafusal muscle fibres, which were classified into five types in accordance with Rowlerson & Spurway (1988). Immunofluorescent reactions with antibodies against slow or fast myosins obtained from anterior or posterior latissimus dorsi muscles (ALD or PLD), respectively,...

  1. Quantitative muscle ultrasound and muscle force in healthy children: A 4-year follow-up study

    NARCIS (Netherlands)

    Jacobs, J.; Jansen, M; Janssen, H.; Raijmann, W.; Alfen, N. van; Pillen, S.

    2013-01-01

    INTRODUCTION: No longitudinal data on the normal development of muscle thickness (MT), quantitative muscle ultrasound echo intensity (EI), and muscle force (MF) in healthy children are yet available. METHODS: Reference values of MT, EI, and MF of 4 muscles from infancy to age 16 years were establish

  2. Muscle fatigue in fibromyalgia is in the brain, not in the muscles

    DEFF Research Database (Denmark)

    Bandak, Elisabeth; Amris, Kirstine; Bliddal, Henning

    2013-01-01

    To investigate relationships between perceived and objectively measured muscle fatigue during exhausting muscle contractions in women with fibromyalgia (FM) compared with healthy controls (HC).......To investigate relationships between perceived and objectively measured muscle fatigue during exhausting muscle contractions in women with fibromyalgia (FM) compared with healthy controls (HC)....

  3. Breast muscle tissue characteristics in growing broilers

    Science.gov (United States)

    Muscle cell development in broilers influences growth rate, breast meat yield, and meat quality. The objective of this study was to characterize muscle tissue changes in breast muscles from two commercial lines of broilers from 21 to 56 days of age. The experiment was designed as a 2×2×6 factorial...

  4. Intramuscular variation in fresh ham muscle color

    Science.gov (United States)

    This experiment was conducted to characterize a defect involving pale muscle tissue in the superficial, ventral portion of ham muscles, resulting in two-toned appearance of cured ham products. Biceps femoris muscles (n = 200), representing 3 production systems, were obtained from the ham-boning lin...

  5. Muscle strength in patients with chronic pain

    NARCIS (Netherlands)

    van Wilgen, C.P.; Akkerman, L.; Wieringa, J.; Dijkstra, P.U.

    2003-01-01

    Objective: To analyse the influence of chronic pain on muscle strength. Design: Muscle strength of patients with unilateral nonspecific chronic pain, in an upper or lower limb, were measured according to a standardized protocol using a hand-held dynamometer. Before and after muscle strength measurem

  6. Primary psoas muscle abscess in pregnancy.

    Science.gov (United States)

    Swanson, Amy; Lau, Kenneth K; Korman, Tony M; Kornman, Tony; Wallace, Euan M; Polyakov, Alex

    2008-12-01

    Primary iliacus-psoas muscle abscess formation is very uncommon during pregnancy. We present a case of a primary iliacus-psoas muscle abscess in pregnancy causing back pain with delayed diagnosis and treatment. Understanding the clinical presentation of iliacus-psoas muscle abscess helps with considering it in the differential diagnosis of back pain during pregnancy.

  7. Muscle MRI findings in facioscapulohumeral muscular dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Gerevini, Simonetta; Caliendo, Giandomenico; Falini, Andrea [IRCCS San Raffaele Scientific Institute, Neuroradiology Unit, Head and Neck Department, Milan (Italy); Scarlato, Marina; Previtali, Stefano Carlo [IRCCS San Raffaele Scientific Institute, Department of Neurology, INSPE and Division of Neuroscience, Milan (Italy); Maggi, Lorenzo; Pasanisi, Barbara; Morandi, Lucia [Fondazione IRCCS Istituto Neurologico ' ' Carlo Besta' ' , Neuromuscular Diseases and Neuroimmunology Unit, Milan (Italy); Cava, Mariangela [IRCCS San Raffaele Scientific Institute, Department of Radiology and Center for Experimental Imaging, Milan (Italy)

    2016-03-15

    Facioscapulohumeral muscular dystrophy (FSHD) is characterized by extremely variable degrees of facial, scapular and lower limb muscle involvement. Clinical and genetic determination can be difficult, as molecular analysis is not always definitive, and other similar muscle disorders may have overlapping clinical manifestations. Whole-body muscle MRI examination for fat infiltration, atrophy and oedema was performed to identify specific patterns of muscle involvement in FSHD patients (30 subjects), and compared to a group of control patients (23) affected by other myopathies (NFSHD). In FSHD patients, we detected a specific pattern of muscle fatty replacement and atrophy, particularly in upper girdle muscles. The most frequently affected muscles, including paucisymptomatic and severely affected FSHD patients, were trapezius, teres major and serratus anterior. Moreover, asymmetric muscle involvement was significantly higher in FSHD as compared to NFSHD patients. In conclusion, muscle MRI is very sensitive for identifying a specific pattern of involvement in FSHD patients and in detecting selective muscle involvement of non-clinically testable muscles. Muscle MRI constitutes a reliable tool for differentiating FSHD from other muscular dystrophies to direct diagnostic molecular analysis, as well as to investigate FSHD natural history and follow-up of the disease. (orig.)

  8. Bones, Muscles, and Joints: The Musculoskeletal System

    Science.gov (United States)

    ... decide to move, the motor cortex sends an electrical signal through the spinal cord and peripheral nerves to the muscles, causing them to contract. The motor cortex on the right side of the brain controls the muscles on the left side of the body and vice versa. The cerebellum coordinates the muscle ...

  9. Interleukin-6 myokine signaling in skeletal muscle

    DEFF Research Database (Denmark)

    Muñoz-Cánoves, Pura; Scheele, Camilla; Pedersen, Bente K

    2013-01-01

    been associated with stimulation of hypertrophic muscle growth and myogenesis through regulation of the proliferative capacity of muscle stem cells. Additional beneficial effects of IL-6 include regulation of energy metabolism, which is related to the capacity of actively contracting muscle...

  10. Effect of transcutaneous electrical muscle stimulation on postoperative muscle mass and protein synthesis

    DEFF Research Database (Denmark)

    Vinge, O; Edvardsen, L; Jensen, F

    1996-01-01

    In an experimental study, 13 patients undergoing major elective abdominal surgery were given postoperative transcutaneous electrical muscle stimulation (TEMS) to the quadriceps femoris muscle on one leg; the opposite leg served as control. Changes in cross-sectional area (CSA) and muscle protein...... muscle protein synthesis and muscle mass after abdominal surgery and should be evaluated in other catabolic states with muscle wasting....... synthesis were assessed by computed tomography and ribosome analysis of percutaneous muscle biopsies before surgery and on the sixth postoperative day. The percentage of polyribosomes in the ribosome suspension decreased significantly (P

  11. Anatomical study of the treatment of cubital tunnel syndrome by endoscope%内窥镜下微创治疗肘管综合征的相关解剖学研究

    Institute of Scientific and Technical Information of China (English)

    郭泉; 庄永青; 魏瑞鸿; 熊洪涛; 姜浩力; 张轩

    2016-01-01

    目的:为内窥镜下进行肘管尺神经减压并前移术提供临床应用解剖基础。方法10例新鲜尸体标本、20例临床病例传统手术中尺神经在臂部、前臂游离长度,尺神经第1肌支距离肱骨内上髁的距离、尺神经前移距离。在4例新鲜尸体标本上模拟手术。结果此术式尺神经前臂、臂部游离距离为(3.90±0.145)cm(3.64~4.23 cm)、(4.21±0.18)cm(3.80~4.53 cm),前移距离(1.49±0.05)cm(1.39~1.57 cm),尺神经第1肌支距离肱骨内上髁距离(2.18±0.38)cm(1.13~2.72cm)。此术式入路点、轴线、层面:肱骨内上髁与尺骨鹰嘴间长约2 cm纵行切口;肱骨内上髁与尺骨鹰嘴之间中点与豌豆骨连线上约7cm长的轴线,肱骨内上髁与尺骨鹰嘴之间中点与肱二头肌内侧肌间隔中点连线上长8cm的轴线;奥本斯韧带、前臂尺侧腕屈肌之间纤维弓形组织表面,臂部深筋膜表面。模拟手术成功。结论研究证实此术式可行,达预期效果。%Objective To provide clinical anatomy for the way of endoscopic anterior ulnar nerve subcutaneous transposition. Methods the length of ulnar nerve free in the forearm and the upper arm,the distance from the first motor branch to the flexor carpi ulnaris muscle tothe medial epicondyle were measured in ten fresh limbs from fresh cadavers and twenty patients. Simulative surgery were performed on four limbs from cadavers. Results In this surgery ,the length of ulnar nerve free in the forearm was(3.90 ± 0.145)cm (3.64~4.23 cm),free in the upper arm was(4.21±0.18)cm(3.80~4.53 cm),the first motor branch to the flexor carpi ulnaris muscle was(2.18 ± 0.38)cm(1.13~2.72 cm)away from the medial humoral epicondyle. In this surgery, the surgical incision was 2 cm longitudinal incision between the medial epicondyle and the olecranon, the forearm axis of the endoscopic operation was about 7 cm line on the line connecting the midpoint between the

  12. The relationship between exercise-induced muscle fatigue, arterial blood flow and muscle perfusion after 56 days local muscle unloading.

    Science.gov (United States)

    Weber, Tobias; Ducos, Michel; Mulder, Edwin; Beijer, Åsa; Herrera, Frankyn; Zange, Jochen; Degens, Hans; Bloch, Wilhelm; Rittweger, Jörn

    2014-05-01

    In the light of the dynamic nature of habitual plantar flexor activity, we utilized an incremental isokinetic exercise test (IIET) to assess the work-related power deficit (WoRPD) as a measure for exercise-induced muscle fatigue before and after prolonged calf muscle unloading and in relation to arterial blood flow and muscle perfusion. Eleven male subjects (31 ± 6 years) wore the HEPHAISTOS unloading orthosis unilaterally for 56 days. It allows habitual ambulation while greatly reducing plantar flexor activity and torque production. Endpoint measurements encompassed arterial blood flow, measured in the femoral artery using Doppler ultrasound, oxygenation of the soleus muscle assessed by near-infrared spectroscopy, lactate concentrations determined in capillary blood and muscle activity using soleus muscle surface electromyography. Furthermore, soleus muscle biopsies were taken to investigate morphological muscle changes. After the intervention, maximal isokinetic torque was reduced by 23·4 ± 8·2% (PBlood flow, tissue oxygenation, lactate concentrations and EMG median frequency kinematics during the exercise test were comparable before and after the intervention, whereas the increase of RMS in response to IIET was less following the intervention (P = 0·03). In conclusion, following submaximal isokinetic muscle work exercise-induced muscle fatigue is unaffected after prolonged local muscle unloading. The observation that arterial blood flow was maintained may underlie the unchanged fatigability.

  13. A Case Report of the Angiosarcoma Involving Epicranial Muscle and Fascia : Is the Occipitofrontalis Muscle Composed of Two Different Muscles?

    Science.gov (United States)

    Kim, Ho Kyun; Lee, Hui Joong

    2016-01-01

    The occipitofrontalis muscle is generally regarded as one muscle composed of two muscle bellies joined through the galea aponeurotica. However, two muscle bellies have different embryological origin, anatomical function and innervations. We report a case of angiosarcoma of the scalp in a 63-year-old man whose MR showed that the superficial fascia overlying the occipital belly becomes the temporoparietal fascia and ends at the superior end of the frontal belly. Beneath the superficial fascia, the occipital belly of the occipitofrontalis muscle becomes the galea aponeurotica and inserts into the underside of the frontal belly. The presented case report supported the concept of which the occipitofrontalis muscle appears to be composed of two anatomically different muscles.

  14. Muscle damage induced by electrical stimulation.

    Science.gov (United States)

    Nosaka, Kazunori; Aldayel, Abdulaziz; Jubeau, Marc; Chen, Trevor C

    2011-10-01

    Electrical stimulation (ES) induces muscle damage that is characterised by histological alterations of muscle fibres and connective tissue, increases in circulating creatine kinase (CK) activity, decreases in muscle strength and development of delayed onset muscle soreness (DOMS). Muscle damage is induced not only by eccentric contractions with ES but also by isometric contractions evoked by ES. Muscle damage profile following 40 isometric contractions of the knee extensors is similar between pulsed current (75 Hz, 400 μs) and alternating current (2.5 kHz delivered at 75 Hz, 400 μs) ES for similar force output. When comparing maximal voluntary and ES-evoked (75 Hz, 200 μs) 50 isometric contractions of the elbow flexors, ES results in greater decreases in maximal voluntary contraction strength, increases in plasma CK activity and DOMS. It appears that the magnitude of muscle damage induced by ES-evoked isometric contractions is comparable to that induced by maximal voluntary eccentric contractions, although the volume of affected muscles in ES is not as large as that of eccentric exercise-induced muscle damage. It seems likely that the muscle damage in ES is associated with high mechanical stress on the activated muscle fibres due to the specificity of motor unit recruitment (i.e., non-selective, synchronous and spatially fixed manner). The magnitude of muscle damage induced by ES is significantly reduced when the second ES bout is performed 2-4 weeks later. It is possible to attenuate the magnitude of muscle damage by "pre-conditioning" muscles, so that muscle damage should not limit the use of ES in training and rehabilitation.

  15. Functional morphology of the thoracolumbar transversospinal muscles.

    Science.gov (United States)

    Cornwall, Jon; Stringer, Mark D; Duxson, Marilyn

    2011-07-15

    STUDY DESIGN. A qualitative and semiquantitative study of the morphology of the human thoracolumbar transversospinal (TSP) muscles. OBJECTIVE. To further define the functional morphology of the thoracolumbar TSP muscles. SUMMARY OF BACKGROUND DATA. The TSP muscle group plays an important role in vertebral function but few studies have rigorously investigated their morphology throughout the thoracolumbar region and details on the location of motor endplates (MEPs) and fiber types are sparse. METHODS. Thoracolumbar TSP muscles were examined by microdissection in five cadavers (seven sides). MEPs were identified using acetylcholinesterase histochemistry in muscles between T5 and S4 unilaterally in two cadavers. The relative proportions of type I and type II skeletal muscle fibers were determined using immunohistochemistry on whole cross sections of every TSP muscle from one side of one cadaver (T5-S4). RESULTS.TSP morphology was homogeneous and consistent throughout the thoracolumbar region. Notable differences to standard descriptions included: (1) consistent attachments between muscles; (2) no discrete cleavage planes between muscles; and (3) attachment sites over the sacrum and to lumbar zygapophysial joints. Previously undescribed small muscles were found attaching to the medial sacrum. All TSP muscles were multipennate, with fibers arranged in parallel having one MEP per muscle fiber. Muscles were highly aerobic (mean proportion of type I fibers 89%), with the proportion of type I fibers decreasing caudally. A significantly greater proportion of type I fibers were found in the midthoracic compared to the low lumbar regions. CONCLUSION. The complex morphology of the TSP muscles indicates that they would be better classified as spinotransverse muscles. They are multipennate, highly aerobic, with fibers organized in parallel, an arrangement lending itself to "fine-tuning" of vertebral movements. Understanding their morphology has implications for investigation

  16. Bone marrow mesenchymal cells improve muscle function in a skeletal muscle re-injury model.

    Directory of Open Access Journals (Sweden)

    Bruno M Andrade

    Full Text Available Skeletal muscle injury is the most common problem in orthopedic and sports medicine, and severe injury leads to fibrosis and muscle dysfunction. Conventional treatment for successive muscle injury is currently controversial, although new therapies, like cell therapy, seem to be promise. We developed a model of successive injuries in rat to evaluate the therapeutic potential of bone marrow mesenchymal cells (BMMC injected directly into the injured muscle. Functional and histological assays were performed 14 and 28 days after the injury protocol by isometric tension recording and picrosirius/Hematoxilin & Eosin staining, respectively. We also evaluated the presence and the fate of BMMC on treated muscles; and muscle fiber regeneration. BMMC treatment increased maximal skeletal muscle contraction 14 and 28 days after muscle injury compared to non-treated group (4.5 ± 1.7 vs 2.5 ± 0.98 N/cm2, p<0.05 and 8.4 ± 2.3 vs. 5.7 ± 1.3 N/cm2, p<0.05 respectively. Furthermore, BMMC treatment increased muscle fiber cross-sectional area and the presence of mature muscle fiber 28 days after muscle injury. However, there was no difference in collagen deposition between groups. Immunoassays for cytoskeleton markers of skeletal and smooth muscle cells revealed an apparent integration of the BMMC within the muscle. These data suggest that BMMC transplantation accelerates and improves muscle function recovery in our extensive muscle re-injury model.

  17. Synchronous monitoring of muscle dynamics and muscle force for maximum isometric tetanus

    Science.gov (United States)

    Zakir Hossain, M.; Grill, Wolfgang

    2010-03-01

    Skeletal muscle is a classic example of a biological soft matter . At both macro and microscopic levels, skeletal muscle is exquisitely oriented for force generation and movement. In addition to the dynamics of contracting and relaxing muscle which can be monitored with ultrasound, variations in the muscle force are also expected to be monitored. To observe such force and sideways expansion variations synchronously for the skeletal muscle a novel detection scheme has been developed. As already introduced for the detection of sideways expansion variations of the muscle, ultrasonic transducers are mounted sideways on opposing positions of the monitored muscle. To detect variations of the muscle force, angle of pull of the monitored muscle has been restricted by the mechanical pull of the sonic force sensor. Under this condition, any variation in the time-of-flight (TOF) of the transmitted ultrasonic signals can be introduced by the variation of the path length between the transducers. The observed variations of the TOF are compared to the signals obtained by ultrasound monitoring for the muscle dynamics. The general behavior of the muscle dynamics and muscle force shows almost an identical concept. Since muscle force also relates the psychological boosting-up effects, the influence of boosting-up on muscle force and muscle dynamics can also be quantified form this study. Length-tension or force-length and force-velocity relationship can also be derived quantitatively with such monitoring.

  18. Emerin increase in regenerating muscle fibers

    Directory of Open Access Journals (Sweden)

    S Squarzoni

    2009-06-01

    Full Text Available The fate of emerin during skeletal muscle regeneration was investigated in an animal model by means of crush injury. Immunofluorescence, immunoblotting and mRNA analysis demonstrated that emerin level is increased in regenerating rat muscle fibers with respect to normal mature myofibers. This finding suggests an involvement of emerin during the muscle fiber regeneration process, in analogy with its reported involvement in muscle cell differentiation in vitro. The impairment of skeletal muscle physiological regeneration or reorganization could be a possible pathogenetic mechanism for Emery Dreifuss muscular dystrophy.

  19. New perspectives of studying gastrointestinal muscle function

    Institute of Scientific and Technical Information of China (English)

    Hans Gregersen; Donghua Liao

    2006-01-01

    The motor function of the gastrointestinal tract has primarily been studied using manometry and radiography,though more indirect tests have also been applied. Manometry and radiography do not provide detailed information about the muscle properties as can be assessed from studies of muscle properties in muscle strips in vitro. In recent years a technique based on impedance planimetric mEasurement of pressure-cross-sectional area relations in a distending bag has proven to provide more detailed information about the muscle function in vivo. This review shows examples of new muscle function analysis such as length-tension diagrams, forcevelocity curves and preload-afterload diagrams.

  20. Pathophysiology of muscle contractures in cerebral palsy.

    Science.gov (United States)

    Mathewson, Margie A; Lieber, Richard L

    2015-02-01

    Patients with cerebral palsy present with a variety of adaptations to muscle structure and function. These pathophysiologic symptoms include functional deficits such as decreased force production and range of motion, in addition to changes in muscle structure such as decreased muscle belly size, increased sarcomere length, and altered extracellular matrix structure and composition. On a cellular level, patients with cerebral palsy have fewer muscle stem cells, termed satellite cells, and altered gene expression. Understanding the nature of these changes may present opportunities for the development of new muscle treatment therapies.

  1. Procedural Options for Measuring Muscle Strength

    Directory of Open Access Journals (Sweden)

    Mindova S.

    2016-10-01

    Full Text Available The aim of the present study was to provide alternative means of measurement and evaluation of muscle strength in rehabilitation practice and diagnostics. In the last few years many electronic devices for evaluation of muscle strength have developed. Contemporary studies have shown that in addition to the standard manual muscle testing muscle strength can be assessed more objectively and analytically using electronic dynamometers and equipment. The strain gauges are used as a tool of precision in the industry that allows measurement of mechanical loads by dynamometers. By using these tools is possible to obtain continuous digital measurement and recording of muscle strength.

  2. Impact of weightlessness on muscle function

    Science.gov (United States)

    Tischler, M. E.; Slentz, M.

    1995-01-01

    The most studied skeletal muscles which depend on gravity, "antigravity" muscles, are located in the posterior portion of the legs. Antigravity muscles are characterized generally by a different fiber type composition than those which are considered nonpostural. The gravity-dependent function of the antigravity muscles makes them particularly sensitive to weightlessness (unweighting) resulting in a substantial loss of muscle protein, with a relatively greater loss of myofibrillar (structural) proteins. Accordingly alpha-actin mRNA decreases in muscle of rats exposed to microgravity. In the legs, the soleus seems particularly responsive to the lack of weight-bearing associated with space flight. The loss of muscle protein leads to a decreased cross-sectional area of muscle fibers, particularly of the slow-twitch, oxidative (SO) ones compared to fast-twitch glycolytic (FG) or oxidative-glycolytic (FOG) fibers. In some muscles, a shift in fiber composition from SO to FOG has been reported in the adaptation to spaceflight. Changes in muscle composition with spaceflight have been associated with decreased maximal isometric tension (Po) and increased maximal shortening velocity. In terms of fuel metabolism, results varied depending on the pathway considered. Glucose uptake, in the presence of insulin, and activities of glycolytic enzymes are increased by space flight. In contrast, oxidation of fatty acids may be diminished. Oxidation of pyruvate, activity of the citric acid cycle, and ketone metabolism in muscle seem to be unaffected by microgravity.

  3. Pathophysiology of muscle dysfunction in COPD.

    Science.gov (United States)

    Gea, Joaquim; Agustí, Alvar; Roca, Josep

    2013-05-01

    Muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD) and may involve both respiratory and locomotor (peripheral) muscles. The loss of strength and/or endurance in the former can lead to ventilatory insufficiency, whereas in the latter it limits exercise capacity and activities of daily life. Muscle dysfunction is the consequence of complex interactions between local and systemic factors, frequently coexisting in COPD patients. Pulmonary hyperinflation along with the increase in work of breathing that occur in COPD appear as the main contributing factors to respiratory muscle dysfunction. By contrast, deconditioning seems to play a key role in peripheral muscle dysfunction. However, additional systemic factors, including tobacco smoking, systemic inflammation, exercise, exacerbations, nutritional and gas exchange abnormalities, anabolic insufficiency, comorbidities and drugs, can also influence the function of both respiratory and peripheral muscles, by inducing modifications in their local microenvironment. Under all these circumstances, protein metabolism imbalance, oxidative stress, inflammatory events, as well as muscle injury may occur, determining the final structure and modulating the function of different muscle groups. Respiratory muscles show signs of injury as well as an increase in several elements involved in aerobic metabolism (proportion of type I fibers, capillary density, and aerobic enzyme activity) whereas limb muscles exhibit a loss of the same elements, injury, and a reduction in fiber size. In the present review we examine the current state of the art of the pathophysiology of muscle dysfunction in COPD.

  4. Kinetics of glucose transport in rat muscle

    DEFF Research Database (Denmark)

    Ploug, Thorkil; Galbo, H; Vinten, J

    1987-01-01

    The effects of insulin and prior muscle contractions, respectively, on 3-O-methylglucose (3-O-MG) transport in skeletal muscle were studied in the perfused rat hindquarter. Initial rates of entry of 3-O-MG in red gastrocnemius, soleus, and white gastrocnemius muscles as a function of perfusate 3-O...... muscles. The effects of both contractions and insulin were greater in red than in white muscles. In red but not in white muscles, maximum increases in Vmax elicited by contractions and by insulin were additive. Both insulin and contractions decreased the half-saturating substrate concentration for glucose...... transport (apparent Km) in all three muscles, in fast-twitch fibers from 70 to approximately 7 mM and in slow-twitch fibers from 12 to 7 mM. After contractions, reversal of contraction-induced glucose transport was monoexponential in red fibers, with a half-time of 7 and 15 min in slow- and fast...

  5. Skeletal muscle regeneration in cancer cachexia.

    Science.gov (United States)

    Bossola, Maurizio; Marzetti, Emanuele; Rosa, Fausto; Pacelli, Fabio

    2016-05-01

    Muscle wasting is the most important phenotypic and clinical feature of cancer cachexia, and the principal cause of impaired physical function, fatigue, and respiratory complications. Muscle loss has been attributed to a variable combination of reduced nutritional intake and an imbalance between anabolic and catabolic processes. It has been suggested that defective skeletal muscle regeneration may also contribute to muscle wasting in cancer patients. However, there is little in vitro or in vivo data available, in either animals or in humans, regarding skeletal muscle regeneration in cancer wasting. The aim of the present review is to define the role of skeletal muscle regeneration in the muscle wasting of cancer patients and to determine possible therapeutic implications.

  6. Satellite cells in human skeletal muscle plasticity.

    Science.gov (United States)

    Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

    2015-01-01

    Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  7. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    DEFF Research Database (Denmark)

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I

    2014-01-01

    Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial function. Therefore, this study examined mitochondrial respiratory rates in the smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscle. Cardiac......, skeletal, and smooth muscle was harvested from a total of 22 subjects (53±6 yrs) and mitochondrial respiration assessed in permeabilized fibers. Complex I+II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac, skeletal, to smooth muscle (54±1; 39±4; 15......±1 pmol•s(-1)•mg (-1), psmooth muscle (222±13; 115±2; 48±2 umol•g(-1)•min(-1), p

  8. Topographic study of the sphenomandibular muscle

    Directory of Open Access Journals (Sweden)

    Raulino Naves Borges

    2012-01-01

    Full Text Available The temporal muscle is housed in the fossa of the bone bearing its name – the temporal bone. Its origin, body, and insertion have been well studied, and it has been described as a muscle consisting of three bundles and responsible for various functions. The advancement of technology has allowed the observation of yet another muscle next to this bundle of fi bers and above the temporal muscle, namely the sphenomandibular muscle. The present study was designed to study the topography of the sphenomandibular muscle. Ten anatomical sets (fi ve cadavers were dissected with the intention of displaying the topography of the temporal and sphenomandibular muscles using the techniques of cutting and folding and conventional cross cuts. The folding of the structures and mapping of the muscles was carried out on four cadavers, analyzing their origins and describing their bodies and insertions. On another cadaver, cross-sectional (horizontal, 2 mm-thick slices were made in a sequential manner. We observed the topography of the muscle and its relationship with adjacent structures. The sphenomandibular muscle was found to be independent of the temporal muscle, for its origin is in the zygomatic-frontal complex, lateral to the orbit and overlaying the fi ber of the anterior bundle of the temporal muscle. Its body is separated from the body of the temporal muscle by a thin fascia and is inserted on an oblique line external to the mandible presenting, therefore, its origin, body, and insertion independent of the origin, body, and insertion of the temporal muscle.

  9. Intracellular acidosis enhances the excitability of working muscle.

    Science.gov (United States)

    Pedersen, Thomas H; Nielsen, Ole B; Lamb, Graham D; Stephenson, D George

    2004-08-20

    Intracellular acidification of skeletal muscles is commonly thought to contribute to muscle fatigue. However, intracellular acidosis also acts to preserve muscle excitability when muscles become depolarized, which occurs with working muscles. Here, we show that this process may be mediated by decreased chloride permeability, which enables action potentials to still be propagated along the internal network of tubules in a muscle fiber (the T system) despite muscle depolarization. These results implicate chloride ion channels in muscle function and emphasize that intracellular acidosis of muscle has protective effects during muscle fatigue.

  10. The Gradual Expansion Muscle Flap

    Science.gov (United States)

    2014-01-01

    defects can usu- ally be obtained with a rotational flap , larger size defects commonly require free tissue transfer. A number of techni- ques have...feasible.21,22 Because limb salvage situations occur in which rota- tional muscle coverage is inadequate and free flap coverage is less desirable, we...larger defects which previously would have required free tissue transfer. Surgical Technique The GEM flap for large soft tissue defects of the leg requires

  11. The role of passive muscle stiffness in symptoms of exercise-induced muscle damage.

    Science.gov (United States)

    McHugh, M P; Connolly, D A; Eston, R G; Kremenic, I J; Nicholas, S J; Gleim, G W

    1999-01-01

    We examined whether passive stiffness of an eccentrically exercising muscle group affects the subsequent symptoms of muscle damage. Passive hamstring muscle stiffness was measured during an instrumented straight-leg-raise stretch in 20 subjects (11 men and 9 women) who were subsequently classified as "stiff" (N = 7), "normal" (N = 6), or "compliant" (N = 7). Passive stiffness was 78% higher in the stiff subjects (36.2 +/- 3.3 N.m.rad(-1)) compared with the compliant subjects (20.3 +/- 1.8 N.m.rad(-1)). Subjects then performed six sets of 10 isokinetic (2.6 rad.s(-1)) submaximal (60% maximal voluntary contraction) eccentric actions of the hamstring muscle group. Symptoms of muscle damage were documented by changes in isometric hamstring muscle strength, pain, muscle tenderness, and creatine kinase activity on the following 3 days. Strength loss, pain, muscle tenderness, and creatine kinase activity were significantly greater in the stiff compared with the compliant subjects on the days after eccentric exercise. Greater symptoms of muscle damage in subjects with stiffer hamstring muscles are consistent with the sarcomere strain theory of muscle damage. The present study provides experimental evidence of an association between flexibility and muscle injury. Muscle stiffness and its clinical correlate, static flexibility, are risk factors for more severe symptoms of muscle damage after eccentric exercise.

  12. The effects of Juchumseogi and Juchumseo Jireugi motions of taekwondo on muscle activation of paraspinal muscles.

    Science.gov (United States)

    Baek, Jongmyeng; Lee, Jaeseok; Kim, Jonghyun; Kim, Jeonghun; Han, Dongwook; Byun, Sunghak

    2015-09-01

    [Purpose] The purpose of this study is to examine the effects of Juchumseogi and Juchumseo Jireugi motions on muscle activation of the paraspinal muscles. [Subjects] The subjects of this study were 20 healthy male students who listened to an explanation of the study methods and the purpose of the experiment, and agreed to participate in the study. [Methods] Muscle activation measurements of the paraspinal muscles at C3, T7, and L3 were taken while standing still and while performing Juchumseogi and Juchumseo Jireugi movements. The Juchumseogi and Juchumseo Jireugi motions were performed 3 times, and its mean value was used for analysis. [Results] The right and left muscle activation of paraspinal muscles induced by Juchumseogi and Juchumseo Jireugi motions in C3 and T7 were significantly higher than those induced by just standing. Muscle activation of paraspinal muscles induced by Juchumseo Jireugi motions in C3, T7, and L3 were significantly higher than those induced by Juchumseogi alone. The right and left muscle activation of paraspinal muscles induced by Juchumseo Jireugi motion in C3, T7, and L3 were significantly higher than those induced by standing and Juchumseogi alone. [Conclusion] This study demonstrated that Juchumseogi and Juchumseo Jireugi motions of Taekwondo could increase muscle activation of paraspinal muscles, and Juchumseo Jireugi motions were more effective for enhancing muscle activation of paraspinal muscles.

  13. Postinjection Muscle Fibrosis from Lupron

    Directory of Open Access Journals (Sweden)

    Erica Everest

    2015-01-01

    Full Text Available We describe the case of a 6.5-year-old girl with central precocious puberty (CPP, which signifies the onset of secondary sexual characteristics before the age of eight in females and the age of nine in males as a result of stimulation of the hypothalamic-pituitary-gonadal axis. Her case is likely related to her adoption, as children who are adopted internationally have much higher rates of CPP. She had left breast development at Tanner Stage 2, adult body odor, and mildly advanced bone age. In order to halt puberty and maximize adult height, she was prescribed a gonadotropin releasing hormone analog, the first line treatment for CPP. She was administered Lupron (leuprolide acetate Depot-Ped (3 months intramuscularly. After her second injection, she developed swelling and muscle pain at the injection site on her right thigh. She also reported an impaired ability to walk. She was diagnosed with muscle fibrosis. This is the first reported case of muscle fibrosis resulting from Lupron injection.

  14. Muscle Atrophy Reversed by Growth Factor Activation of Satellite Cells in a Mouse Muscle Atrophy Model

    DEFF Research Database (Denmark)

    Hauerslev, Simon; Vissing, John; Krag, Thomas O

    2014-01-01

    mechanism that may contribute to the progressive muscle wasting seen in severely affected patients with muscular dystrophy and significant on-going regeneration. This treatment could potentially be applied to many conditions that feature muscle wasting to increase muscle bulk and strength.......Muscular dystrophies comprise a large group of inherited disorders that lead to progressive muscle wasting. We wanted to investigate if targeting satellite cells can enhance muscle regeneration and thus increase muscle mass. We treated mice with hepatocyte growth factor and leukemia inhibitory...

  15. Engineering skeletal muscle tissue in bioreactor systems

    Institute of Scientific and Technical Information of China (English)

    An Yang; Li Dong

    2014-01-01

    Objective To give a concise review of the current state of the art in tissue engineering (TE) related to skeletal muscle and kinds of bioreactor environment.Data sources The review was based on data obtained from the published articles and guidelines.Study selection A total of 106 articles were selected from several hundred original articles or reviews.The content of selected articles is in accordance with our purpose and the authors are authorized scientists in the study of engineered muscle tissue in bioreactor.Results Skeletal muscle TE is a promising interdisciplinary field which aims at the reconstruction of skeletal muscle loss.Although numerous studies have indicated that engineering skeletal muscle tissue may be of great importance in medicine in the near future,this technique still represents a limited degree of success.Since tissue-engineered muscle constructs require an adequate connection to the vascular system for efficient transport of oxygen,carbon dioxide,nutrients and waste products.Moreover,functional and clinically applicable muscle constructs depend on adequate neuromuscular junctions with neural calls.Third,in order to engineer muscle tissue successfully,it may be beneficial to mimic the in vivo environment of muscle through association with adequate stimuli from bioreactors.Conclusion Vascular system and bioreactors are necessary for development and maintenance of engineered muscle in order to provide circulation within the construct.

  16. Space travel directly induces skeletal muscle atrophy

    Science.gov (United States)

    Vandenburgh, H.; Chromiak, J.; Shansky, J.; Del Tatto, M.; Lemaire, J.

    1999-01-01

    Space travel causes rapid and pronounced skeletal muscle wasting in humans that reduces their long-term flight capabilities. To develop effective countermeasures, the basis of this atrophy needs to be better understood. Space travel may cause muscle atrophy indirectly by altering circulating levels of factors such as growth hormone, glucocorticoids, and anabolic steroids and/or by a direct effect on the muscle fibers themselves. To determine whether skeletal muscle cells are directly affected by space travel, tissue-cultured avian skeletal muscle cells were tissue engineered into bioartificial muscles and flown in perfusion bioreactors for 9 to 10 days aboard the Space Transportation System (STS, i.e., Space Shuttle). Significant muscle fiber atrophy occurred due to a decrease in protein synthesis rates without alterations in protein degradation. Return of the muscle cells to Earth stimulated protein synthesis rates of both muscle-specific and extracellular matrix proteins relative to ground controls. These results show for the first time that skeletal muscle fibers are directly responsive to space travel and should be a target for countermeasure development.

  17. Muscle activity characterization by laser Doppler Myography

    Science.gov (United States)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Primo Tomasini, Enrico

    2013-09-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin.

  18. Redox control of skeletal muscle atrophy.

    Science.gov (United States)

    Powers, Scott K; Morton, Aaron B; Ahn, Bumsoo; Smuder, Ashley J

    2016-09-01

    Skeletal muscles comprise the largest organ system in the body and play an essential role in body movement, breathing, and glucose homeostasis. Skeletal muscle is also an important endocrine organ that contributes to the health of numerous body organs. Therefore, maintaining healthy skeletal muscles is important to support overall health of the body. Prolonged periods of muscle inactivity (e.g., bed rest or limb immobilization) or chronic inflammatory diseases (i.e., cancer, kidney failure, etc.) result in skeletal muscle atrophy. An excessive loss of muscle mass is associated with a poor prognosis in several diseases and significant muscle weakness impairs the quality of life. The skeletal muscle atrophy that occurs in response to inflammatory diseases or prolonged inactivity is often associated with both oxidative and nitrosative stress. In this report, we critically review the experimental evidence that provides support for a causative link between oxidants and muscle atrophy. More specifically, this review will debate the sources of oxidant production in skeletal muscle undergoing atrophy as well as provide a detailed discussion on how reactive oxygen species and reactive nitrogen species modulate the signaling pathways that regulate both protein synthesis and protein breakdown.

  19. Synchronous monitoring of muscle dynamics and electromyogram

    Science.gov (United States)

    Zakir Hossain, M.; Grill, Wolfgang

    2011-04-01

    A non-intrusive novel detection scheme has been implemented to detect the lateral muscle extension, force of the skeletal muscle and the motor action potential (EMG) synchronously. This allows the comparison of muscle dynamics and EMG signals as a basis for modeling and further studies to determine which architectural parameters are most sensitive to changes in muscle activity. For this purpose the transmission time for ultrasonic chirp signal in the frequency range of 100 kHz to 2.5 MHz passing through the muscle under observation and respective motor action potentials are recorded synchronously to monitor and quantify biomechanical parameters related to muscle performance. Additionally an ultrasonic force sensor has been employed for monitoring. Ultrasonic traducers are placed on the skin to monitor muscle expansion. Surface electrodes are placed suitably to pick up the potential for activation of the monitored muscle. Isometric contraction of the monitored muscle is ensured by restricting the joint motion with the ultrasonic force sensor. Synchronous monitoring was initiated by a software activated audio beep starting at zero time of the subsequent data acquisition interval. Computer controlled electronics are used to generate and detect the ultrasonic signals and monitor the EMG signals. Custom developed software and data analysis is employed to analyze and quantify the monitored data. Reaction time, nerve conduction speed, latent period between the on-set of EMG signals and muscle response, degree of muscle activation and muscle fatigue development, rate of energy expenditure and motor neuron recruitment rate in isometric contraction, and other relevant parameters relating to muscle performance have been quantified with high spatial and temporal resolution.

  20. Quantitative Muscle Ultrasonography in Carpal Tunnel Syndrome

    Science.gov (United States)

    2016-01-01

    Objective To assess the reliability of quantitative muscle ultrasonography (US) in healthy subjects and to evaluate the correlation between quantitative muscle US findings and electrodiagnostic study results in patients with carpal tunnel syndrome (CTS). The clinical significance of quantitative muscle US in CTS was also assessed. Methods Twenty patients with CTS and 20 age-matched healthy volunteers were recruited. All control and CTS subjects underwent a bilateral median and ulnar nerve conduction study (NCS) and quantitative muscle US. Transverse US images of the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) were obtained to measure muscle cross-sectional area (CSA), thickness, and echo intensity (EI). EI was determined using computer-assisted, grayscale analysis. Inter-rater and intra-rater reliability for quantitative muscle US in control subjects, and differences in muscle thickness, CSA, and EI between the CTS patient and control groups were analyzed. Relationships between quantitative US parameters and electrodiagnostic study results were evaluated. Results Quantitative muscle US had high inter-rater and intra-rater reliability in the control group. Muscle thickness and CSA were significantly decreased, and EI was significantly increased in the APB of the CTS group (all p<0.05). EI demonstrated a significant positive correlation with latency of the median motor and sensory NCS in CTS patients (p<0.05). Conclusion These findings suggest that quantitative muscle US parameters may be useful for detecting muscle changes in CTS. Further study involving patients with other neuromuscular diseases is needed to evaluate peripheral muscle change using quantitative muscle US. PMID:28119835

  1. [Masticatory muscles. Part III. Biomechanics of the masticatory muscles].

    Science.gov (United States)

    Koolstra, J H

    1997-08-01

    The masticatory muscles are able to produce forces. These forces may cause movements of the lower jaw. Furthermore, they can be applied by the teeth for the generation of bite or chewing forces. During these kind of processes the temporomandibular joints will be loaded also. The interaction between forces and movements in the masticatory system is complex but obeys the relatively simple laws of mechanics. By application of these laws the development of joint loading, force patterns and movements during masticatory function and dysfunction can be understood. This is illustrated by a few examples of both statical and dynamical masticatory performance.

  2. THREE INTERMITTENT SESSIONS OF CRYOTHERAPY REDUCE THE SECONDARY MUSCLE INJURY IN SKELETAL MUSCLE OF RAT

    Directory of Open Access Journals (Sweden)

    Nuno M. L. Oliveira

    2006-06-01

    Full Text Available Although cryotherapy associated to compression is recommended as immediate treatment after muscle injury, the effect of intermittent sessions of these procedures in the area of secondary muscle injury is not established. This study examined the effect of three sessions of cryotherapy (30 min of ice pack each 2h and muscle compression (sand pack in the muscle-injured area. Twenty-four Wistar rats (312 ± 20g were evaluated. In three groups, the middle belly of tibialis anterior (TA muscle was injured by a frozen iron bar and received one of the following treatments: a three sessions of cryotherapy; b three sessions of compression; c not treated. An uninjured group received sessions of cryotherapy. Frozen muscles were cross- sectioned (10 µm and stained for the measurement of injured and uninjured muscle area. Injured muscles submitted to cryotherapy showed the smallest injured area (29.83 ± 6.6%, compared to compressed (39.2 ± 2.8%, p= 0.003 and untreated muscles (41.74 ± 4.0%, p = 0.0008. No difference was found between injured compressed and injured untreated muscles. In conclusion, three intermittent sessions of cryotherapy applied immediately after muscle damage was able to reduce the secondary muscle injury, while only the muscle compression did not provide the same effectiveness

  3. Neural control of muscle relaxation in echinoderms.

    Science.gov (United States)

    Elphick, M R; Melarange, R

    2001-03-01

    Smooth muscle relaxation in vertebrates is regulated by a variety of neuronal signalling molecules, including neuropeptides and nitric oxide (NO). The physiology of muscle relaxation in echinoderms is of particular interest because these animals are evolutionarily more closely related to the vertebrates than to the majority of invertebrate phyla. However, whilst in vertebrates there is a clear structural and functional distinction between visceral smooth muscle and skeletal striated muscle, this does not apply to echinoderms, in which the majority of muscles, whether associated with the body wall skeleton and its appendages or with visceral organs, are made up of non-striated fibres. The mechanisms by which the nervous system controls muscle relaxation in echinoderms were, until recently, unknown. Using the cardiac stomach of the starfish Asterias rubens as a model, it has been established that the NO-cGMP signalling pathway mediates relaxation. NO also causes relaxation of sea urchin tube feet, and NO may therefore function as a 'universal' muscle relaxant in echinoderms. The first neuropeptides to be identified in echinoderms were two related peptides isolated from Asterias rubens known as SALMFamide-1 (S1) and SALMFamide-2 (S2). Both S1 and S2 cause relaxation of the starfish cardiac stomach, but with S2 being approximately ten times more potent than S1. SALMFamide neuropeptides have also been isolated from sea cucumbers, in which they cause relaxation of both gut and body wall muscle. Therefore, like NO, SALMFamides may also function as 'universal' muscle relaxants in echinoderms. The mechanisms by which SALMFamides cause relaxation of echinoderm muscle are not known, but several candidate signal transduction pathways are discussed here. The SALMFamides do not, however, appear to act by promoting release of NO, and muscle relaxation in echinoderms is therefore probably regulated by at least two neuronal signalling systems acting in parallel. Recently, other

  4. Lactate and force production in skeletal muscle

    DEFF Research Database (Denmark)

    Kristensen, Michael; Albertsen, Janni; Rentsch, Maria;

    2005-01-01

    Lactic acid accumulation is generally believed to be involved in muscle fatigue. However, one study reported that in rat soleus muscle (in vitro), with force depressed by high external K+ concentrations a subsequent incubation with lactic acid restores force and thereby protects against fatigue....... However, incubation with 20 mm lactic acid reduces the pH gradient across the sarcolemma, whereas the gradient is increased during muscle activity. Furthermore, unlike active muscle the Na+-K+ pump is not activated. We therefore hypothesized that lactic acid does not protect against fatigue in active...... muscle. Three incubation solutions were used: 20 mm Na-lactate (which acidifies internal pH), 12 mm Na-lactate +8 mm lactic acid (which mimics the pH changes during muscle activity), and 20 mm lactic acid (which acidifies external pH more than internal pH). All three solutions improved force in K...

  5. Increased skeletal muscle capillarization enhances insulin sensitivity

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Laub, Lasse; Vedel, Kenneth;

    2014-01-01

    Increased skeletal muscle capillarization is associated with improved glucose tolerance and insulin sensitivity. However, a possible causal relationship has not previously been identified. We therefore investigated whether increased skeletal muscle capillarization increases insulin sensitivity....... Skeletal muscle specific angiogenesis was induced by adding the α1-adrenergic receptor antagonist Prazosin to the drinking water of Sprague Dawley rats (n=33) while 34 rats served as controls. Insulin sensitivity was measured ≥40 h after termination of the 3-week Prazosin treatment, which ensured......-body insulin sensitivity increased by ~24% and insulin-stimulated skeletal muscle 2-deoxy-[(3)H]-Glucose disposal increased by ~30% concomitant with a ~20% increase in skeletal muscle capillarization. Adipose tissue insulin sensitivity was not affected by the treatment. Insulin-stimulated muscle glucose uptake...

  6. Muscle biopsy findings in inflammatory myopathies.

    Science.gov (United States)

    Dalakas, Marinos C

    2002-11-01

    The inflammatory myopathies encompass a heterogeneous group of acquired muscle diseases characterized clinically, by muscle weakness, and histologically, by inflammatory infiltrates within the skeletal muscles. The group of these myopathies comprise three major and discrete subsets: polymyositis (PM), dermatomyositis (DM), and inclusion body myositis (IBM). Each subset retains its characteristic clinical, immunopathologic, and morphologic features regardless of whether it occurs separately or in connection with other systemic diseases. Although the diagnosis of these disorders is based on the combination of clinical examination, electromyographic data, serum muscle enzyme levels, various autoantibodies, and the muscle biopsy findings, the muscle biopsy offers the most definitive diagnostic information in the majority of the cases. This article summarizes the main histologic features that characterize PM, DM, or IBM and emphasizes the main pitfalls associated with interpretation of the biopsies.

  7. [Molecular mechanisms of skeletal muscle hypertrophy].

    Science.gov (United States)

    Astratenkova, I V; Rogozkin, V A

    2014-06-01

    Enzymes Akt, AMPK, mTOR, S6K and PGC-1a coactivator take part in skeletal muscles in the regulation of synthesis of proteins. The expression of these proteins is regulated by growth factors, hormones, nutrients, mechanical loading and leads to an increase in muscle mass and skeletal muscle hypertrophy. The review presents the results of studies published in the past four years, which expand knowledge on the effects of various factors on protein synthesis in skeletal muscle. The attention is focused on the achievements that reveal and clarify the signaling pathways involved in the regulation of protein synthesis in skeletal muscle. The central place is taken by mTOR enzyme which controls and regulates the main stages of the cascade of reactions of muscle proteins providing synthesis in the conditions of human life. coactivator PGC-1a.

  8. The exercised skeletal muscle: a review

    Directory of Open Access Journals (Sweden)

    Marina Marini

    2010-09-01

    Full Text Available The skeletal muscle is the second more plastic tissue of the body - second to the nervous tissue only. In fact, both physical activity and inactivity contribute to modify the skeletal muscle, by continuous signaling through nerve impulses, mechanical stimuli and humoral clues. In turn, the skeletal muscle sends signals to the body, thus contributing to its homeostasis. We'll review here the contribute of physical exercise to the shaping of skeletal muscle, to the adaptation of its mass and function to the different needs imposed by different physical activities and to the attainment of the health benefits associated with active skeletal muscles. Focus will primarily be on the molecular pathways and on gene regulation that result in skeletal muscle adaptation to exercise.

  9. Cytokines: muscle protein and amino acid metabolism

    DEFF Research Database (Denmark)

    van Hall, Gerrit

    2012-01-01

    raises TNF-α and IL-6 to moderate levels, has only identified IL-6 as a potent cytokine, decreasing systemic amino acid levels and muscle protein metabolism. The marked decrease in circulatory and muscle amino acid concentrations was observed with a concomitant reduction in both the rates of muscle...... protein synthesis and breakdown, that is, reduced turnover with a minor increase in net muscle degradation. Very similar observations have been made in models of acute inflammation, induced by high-dose endotoxin injection. However, these changes were suggested not to be attributed to a direct effect...... of IL-6 on the regulation of muscle protein metabolism but indirectly via IL-6 reducing amino acid availability. SUMMARY: Recent studies suggest that the best described cytokines TNF-α and IL-6 are unlikely to be the major direct mediators of muscle protein loss in inflammatory diseases. However...

  10. Radioisotope scanning in inflammatory muscle disease

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M.B.; Swift, T.R.; Spies, S.M.

    1976-06-01

    Fourteen whole-body rectilinear bone scans using technetium 99m-polyphosphate were done in nine patients with well-documented inflammatory myopathy (either polymyositis or dermatomyositis). In all nine patients the scans showed evidence of increased muscle labeling. Muscle uptake was markedly increased in one patient, moderately increased in two patients, and minimally increased in six patients. The degree of muscle labeling correlated with the severity of the muscle weakness at the time the scan was done. In four patients, who received high-dose corticosteroid treatment, muscle uptake was decreased following therapy. These findings suggest that radioisotope scanning may be useful in the diagnosis and management of patients with inflammatory muscle diseases.

  11. Traumatic avulsion of extraocular muscles: case reports

    Directory of Open Access Journals (Sweden)

    Nilza Minguini

    2013-04-01

    Full Text Available We described the clinical, surgical details and results (motor and sensory of the retrieving procedure of traumatically avulsed muscles in three patients with no previous history of strabismus or diplopia seen in the Department of Ophthalmology, State University of Campinas, Brazil. The slipped muscle portion was reinserted at the original insertion and under the remaining stump, which was sutured over the reinserted muscle. For all three cases there was recovery of single binocular vision and stereopsis.

  12. Intrafusal muscle fibre types in frog spindles.

    OpenAIRE

    Diwan, F H; Ito, F

    1989-01-01

    Muscle spindles from bullfrog semitendinosus, iliofibularis and sartorius muscles were examined with light and electron microscopy. Four types of intrafusal muscle fibre were identified according to their diameter, central nucleation and reticular zone arrangement: a large nuclear bag fibre, a medium nuclear bag fibre, and two types of small nuclear chain fibres with and without a reticular zone, respectively. It is suggested that they are comparable to the nuclear bag1, bag2 and chain fibres...

  13. A Depolarizing Electrogenic Pump in Frog Muscle

    Science.gov (United States)

    1975-08-01

    mw copy AFRRI SR75-20 AUGUST 1975 AFRRI SCIENTIFIC REPORT O ■ to A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. Geduldig D. R...Academy of Sciences - National Research Council. AFRRI SR75-20 August 1975 A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. GEDULDIG* D. R...INTRODUCTION When Na-enriched frog muscles are bathed in Na- and K-free saline, the small amount of potassium which could accumulate outside of the membrane

  14. Airway Epithelium Stimulates Smooth Muscle Proliferation

    OpenAIRE

    Malavia, Nikita K.; Raub, Christopher B.; Mahon, Sari B.; Brenner, Matthew; Reynold A Panettieri; George, Steven C.

    2009-01-01

    Communication between the airway epithelium and stroma is evident during embryogenesis, and both epithelial shedding and increased smooth muscle proliferation are features of airway remodeling. Hence, we hypothesized that after injury the airway epithelium could modulate airway smooth muscle proliferation. Fully differentiated primary normal human bronchial epithelial (NHBE) cells at an air–liquid interface were co-cultured with serum-deprived normal primary human airway smooth muscle cells (...

  15. Perceived Muscle Soreness in Recreational Female Runners

    OpenAIRE

    Burnett, D; Smith, K; Smeltzer, C.; Young, K.; Burns, S

    2010-01-01

    The purpose of this study was to determine if rating of perceived exertion correlated with perceived muscle soreness during delayed onset muscle soreness (DOMS) in female runners. This study examined the pre and post running economy measures and perceived muscle soreness before and after a 30-min downhill run (DHR) at −15% grade and 70% of the subjects predetermined maximum oxygen uptake (VO2 peak). Six female recreational runners (mean age = 24.5) performed level running at 65%, 75%, and 85%...

  16. The transduction properties of intercostal muscle mechanoreceptors

    Directory of Open Access Journals (Sweden)

    Johnson Richard D

    2002-10-01

    Full Text Available Abstract Background Intercostal muscles are richly innervated by mechanoreceptors. In vivo studies of cat intercostal muscle have shown that there are 3 populations of intercostal muscle mechanoreceptors: primary muscle spindles (1°, secondary muscle spindles (2° and Golgi tendon organs (GTO. The purpose of this study was to determine the mechanical transduction properties of intercostal muscle mechanoreceptors in response to controlled length and velocity displacements of the intercostal space. Mechanoreceptors, recorded from dorsal root fibers, were localized within an isolated intercostal muscle space (ICS. Changes in ICS displacement and the velocity of ICS displacement were independently controlled with an electromagnetic motor. ICS velocity (0.5 – 100 μm/msec to a displacement of 2,000 μm and displacement (50–2,000 μm at a constant velocity of 10 μm/msec parameters encompassed the full range of rib motion. Results Both 1° and 2° muscle spindles were found evenly distributed within the ICS. GTOs were localized along the rib borders. The 1° spindles had the greatest discharge frequency in response to displacement amplitude followed by the 2° afferents and GTOs. The 1° muscle spindles also possessed the greatest discharge frequency in response to graded velocity changes, 3.0 spikes·sec-1/μm·msec-1. GTOs had a velocity response of 2.4 spikes·sec-1/μm·msec-1 followed by 2° muscle spindles at 0.6 spikes·sec-1/μm·msec-1. Conclusion The results of this study provide a systematic description of the mechanosenitivity of the 3 types of intercostal muscle mechanoreceptors. These mechanoreceptors have discharge properties that transduce the magnitude and velocity of intercostal muscle length.

  17. Role of Smooth Muscle in Intestinal Inflammation

    Directory of Open Access Journals (Sweden)

    Stephen M Collins

    1996-01-01

    Full Text Available The notion that smooth muscle function is altered in inflammation is prompted by clinical observations of altered motility in patients with inflammatory bowel disease (IBD. While altered motility may reflect inflammation-induced changes in intrinsic or extrinsic nerves to the gut, changes in gut hormone release and changes in muscle function, recent studies have provided in vitro evidence of altered muscle contractility in muscle resected from patients with ulcerative colitis or Crohn’s disease. In addition, the observation that smooth muscle cells are more numerous and prominent in the strictured bowel of IBD patients compared with controls suggests that inflammation may alter the growth of intestinal smooth muscle. Thus, inflammation is associated with changes in smooth muscle growth and contractility that, in turn, contribute to important symptoms of IBD including diarrhea (from altered motility and pain (via either altered motility or stricture formation. The involvement of smooth muscle in this context may be as an innocent bystander, where cells and products of the inflammatory process induce alterations in muscle contractility and growth. However, it is likely that intestinal muscle cells play a more active role in the inflammatory process via the elaboration of mediators and trophic factors, including cytokines, and via the production of collagen. The concept of muscle cells as active participants in the intestinal inflammatory process is a new concept that is under intense study. This report summarizes current knowledge as it relates to these two aspects of altered muscle function (growth and contractility in the inflamed intestine, and will focus on mechanisms underlying these changes, based on data obtained from animal models of intestinal inflammation.

  18. Impaired muscle glycogen resynthesis after a marathon is not caused by decreased muscle GLUT-4 content

    DEFF Research Database (Denmark)

    Asp, S; Rohde, T; Richter, Erik

    1997-01-01

    -race levels 7 days after the race. We conclude that the total GLUT-4 protein content is unaltered in the lateral gastrocnemius after a competitive marathon and that the slow recovery of muscle glycogen after the race apparently involves factors other than changes in the total content of this protein.......Our purpose was to investigate whether the slow rate of muscle glycogen resynthesis after a competitive marathon is associated with a decrease in the total muscle content of the muscle glucose transporter (GLUT-4). Seven well-trained marathon runners participated in the study, and muscle biopsies...... were obtained from the lateral head of the gastrocnemius muscle before, immediately after, and 1, 2, and 7 days after the marathon, as were venous blood samples. Muscle GLUT-4 content was unaltered over the experimental period. Muscle glycogen concentration was 758 +/- 53 mmol/kg dry weight before...

  19. Magnetic stimulation of muscle evokes cerebral potentials in assessment of paraspinal muscle spasm.

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Objectlve: To assess the muscle spasm by magnetic stimulation of muscle evokes cerebral potentials (MMSEP). Methods: Paraspinal MMSEP and function assessment was recorded in detail before and after treat-

  20. Direct optical activation of skeletal muscle fibres efficiently controls muscle contraction and attenuates denervation atrophy.

    Science.gov (United States)

    Magown, Philippe; Shettar, Basavaraj; Zhang, Ying; Rafuse, Victor F

    2015-10-13

    Neural prostheses can restore meaningful function to paralysed muscles by electrically stimulating innervating motor axons, but fail when muscles are completely denervated, as seen in amyotrophic lateral sclerosis, or after a peripheral nerve or spinal cord injury. Here we show that channelrhodopsin-2 is expressed within the sarcolemma and T-tubules of skeletal muscle fibres in transgenic mice. This expression pattern allows for optical control of muscle contraction with comparable forces to nerve stimulation. Force can be controlled by varying light pulse intensity, duration or frequency. Light-stimulated muscle fibres depolarize proportionally to light intensity and duration. Denervated triceps surae muscles transcutaneously stimulated optically on a daily basis for 10 days show a significant attenuation in atrophy resulting in significantly greater contractile forces compared with chronically denervated muscles. Together, this study shows that channelrhodopsin-2/H134R can be used to restore function to permanently denervated muscles and reduce pathophysiological changes associated with denervation pathologies.

  1. Conduction velocity of antigravity muscle action potentials.

    Science.gov (United States)

    Christova, L; Kosarov, D; Christova, P

    1992-01-01

    The conduction velocity of the impulses along the muscle fibers is one of the parameters of the extraterritorial potentials of the motor units allowing for the evaluation of the functional state of the muscles. There are no data about the conduction velocities of antigravity muscleaction potentials. In this paper we offer a method for measuring conduction velocity of potentials of single MUs and the averaged potentials of the interference electromiogram (IEMG) lead-off by surface electrodes from mm. sternocleidomastoideus, trapezius, deltoideus (caput laterale) and vastus medialis. The measured mean values of the conduction velocity of antigravity muscles potentials can be used for testing the functional state of the muscles.

  2. Cellular and molecular mechanisms of muscle atrophy

    Directory of Open Access Journals (Sweden)

    Paolo Bonaldo

    2013-01-01

    Full Text Available Skeletal muscle is a plastic organ that is maintained by multiple pathways regulating cell and protein turnover. During muscle atrophy, proteolytic systems are activated, and contractile proteins and organelles are removed, resulting in the shrinkage of muscle fibers. Excessive loss of muscle mass is associated with poor prognosis in several diseases, including myopathies and muscular dystrophies, as well as in systemic disorders such as cancer, diabetes, sepsis and heart failure. Muscle loss also occurs during aging. In this paper, we review the key mechanisms that regulate the turnover of contractile proteins and organelles in muscle tissue, and discuss how impairments in these mechanisms can contribute to muscle atrophy. We also discuss how protein synthesis and degradation are coordinately regulated by signaling pathways that are influenced by mechanical stress, physical activity, and the availability of nutrients and growth factors. Understanding how these pathways regulate muscle mass will provide new therapeutic targets for the prevention and treatment of muscle atrophy in metabolic and neuromuscular diseases.

  3. Protein oxidation in muscle foods: A review

    DEFF Research Database (Denmark)

    Lund, Marianne; Heinonen, Marina; Baron, Caroline P.

    2011-01-01

    insight into the reactions involved in the oxidative modifications undergone by muscle proteins. Moreover, a variety of products derived from oxidized muscle proteins, including cross-links and carbonyls, have been identified. The impact of oxidation on protein functionality and on specific meat quality...... and consequences of Pox in muscle foods. The efficiency of different anti-oxidant strategies against the oxidation of muscle proteins is also reported.......Protein oxidation in living tissues is known to play an essential role in the pathogenesis of relevant degenerative diseases, whereas the occurrence and impact of protein oxidation (Pox) in food systems have been ignored for decades. Currently, the increasing interest among food scientists...

  4. Muscle relaxant use during intraoperative neurophysiologic monitoring.

    Science.gov (United States)

    Sloan, Tod B

    2013-02-01

    Neuromuscular blocking agents have generally been avoided during intraoperative neurophysiological monitoring (IOM) where muscle responses to nerve stimulation or transcranial stimulation are monitored. However, a variety of studies and clinical experience indicate partial neuromuscular blockade is compatible with monitoring in some patients. This review presents these experiences after reviewing the currently used agents and the methods used to assess the blockade. A review was conducted of the published literature regarding neuromuscular blockade during IOM. A variety of articles have been published that give insight into the use of partial pharmacological paralysis during monitoring. Responses have been recorded from facial muscles, vocalis muscles, and peripheral nerve muscles from transcranial or neural stimulation with neuromuscular blockade measured in the muscle tested or in the thenar muscles from ulnar nerve stimulation. Preconditioning of the nervous system with tetanic or sensory stimulation has been used. In patients without neuromuscular pathology intraoperative monitoring using peripheral muscle responses from neural stimulation is possible with partial neuromuscular blockade. Monitoring of muscle responses from cranial nerve stimulation may require a higher degree of stimulation and less neuromuscular blockade. The role of tetanic or sensory conditioning of the nervous system is not fully characterized. The impact of neuromuscular pathology or the effect of partial blockade on monitoring muscle responses from spontaneous neural activity or mechanical nerve stimulation has not been described.

  5. The number and choice of muscles impact the results of muscle synergy analyses

    Directory of Open Access Journals (Sweden)

    Katherine Muterspaugh Steele

    2013-08-01

    Full Text Available One theory for how humans control movement is that muscles are activated in weighted groups or synergies. Studies have shown that electromyography (EMG from a variety of tasks can be described by a low-dimensional space thought to reflect synergies. These studies use algorithms, such as nonnegative matrix factorization, to identify synergies from EMG. Due to experimental constraints, EMG can rarely be taken from all muscles involved in a task. However, it is unclear if the choice of muscles included in the analysis impacts estimated synergies. The aim of our study was to evaluate the impact of the number and choice of muscles on synergy analyses. We used a musculoskeletal model to calculate muscle activations required to perform an isometric upper-extremity task. Synergies calculated from the activations from the musculoskeletal model were similar to a prior experimental study. To evaluate the impact of the number of muscles included in the analysis, we randomly selected subsets of between 5 and 29 muscles and compared the similarity of the synergies calculated from each subset to a master set of synergies calculated from all muscles. We determined that the structure of synergies is dependent upon the number and choice of muscles included in the analysis. When five muscles were included in the analysis, the similarity of the synergies to the master set was only 0.57 ± 0.54; however, the similarity improved to over 0.8 with more than ten muscles. We identified two methods, selecting dominant muscles from the master set or selecting muscles with the largest maximum isometric force, which significantly improved similarity to the master set and can help guide future experimental design. Analyses that included a small subset of muscles also over-estimated the variance accounted for (VAF by the synergies compared to an analysis with all muscles. Thus, researchers should use caution using VAF to evaluate synergies when EMG is measured from a small

  6. Muscle fibre types in the external eye muscles of the pigeon, Columba livia.

    OpenAIRE

    McVean, A; Stelling, J; Rowlerson, A.

    1987-01-01

    Fibre typing with antisera raised against specific myosin types from muscles of known physiological properties were used to characterise the fibre types within the oculorotatory muscles of pigeons. Fibres reacting strongly to antiserum anti-ALD (specific for tonic fibre myosin) were found lying along the global margin of the muscle and also in a layer lying immediately beneath a discrete band of fibres running along the orbital margin. These fibres resembled those of the skeletal muscle ALD i...

  7. Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

    Science.gov (United States)

    Farrell, E. R.; Fernandes, J.; Keshishian, H.

    1996-01-01

    In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

  8. Relative activity of respiratory muscles during prescribed inspiratory muscle training in healthy people

    OpenAIRE

    Jung, Ju-hyeon; Kim, Nan-soo

    2016-01-01

    [Purpose] This study aimed to determine the effects of different intensities of inspiratory muscle training on the relative respiratory muscle activity in healthy adults. [Subjects and Methods] Thirteen healthy male volunteers were instructed to perform inspiratory muscle training (0%, 40%, 60%, and 80% maximal inspiratory pressure) on the basis of their individual intensities. The inspiratory muscle training was performed in random order of intensities. Surface electromyography data were col...

  9. Increased fatigue resistance of respiratory muscles during exercise after respiratory muscle endurance training

    OpenAIRE

    Verges, S; Lenherr, O; Haner, A C; Schulz, C.; Spengler, C M

    2007-01-01

    Respiratory muscle fatigue develops during exhaustive exercise and can limit exercise performance. Respiratory muscle training, in turn, can increase exercise performance. We investigated whether respiratory muscle endurance training (RMT) reduces exercise-induced inspiratory and expiratory muscle fatigue. Twenty-one healthy, male volunteers performed twenty 30-min sessions of either normocapnic hyperpnoea (n = 13) or sham training (CON, n = 8) over 4-5 wk. Before and after training, subjects...

  10. Chronic Stimulation-Induced Changes in the Rodent Thyroarytenoid Muscle

    Science.gov (United States)

    McMullen, Colleen A.; Butterfield, Timothy A.; Dietrich, Maria; Andreatta, Richard D.; Andrade, Francisco H.; Fry, Lisa; Stemple, Joseph C.

    2011-01-01

    Purpose: Therapies for certain voice disorders purport principles of skeletal muscle rehabilitation to increase muscle mass, strength, and endurance. However, applicability of limb muscle rehabilitation to the laryngeal muscles has not been tested. In this study, the authors examined the feasibility of the rat thyroarytenoid muscle to remodel as a…

  11. Whole-body magnetic resonance imaging in skeletal muscle disease.

    Science.gov (United States)

    Shelly, Martin J; Bolster, Ferdia; Foran, Paul; Crosbie, Ian; Kavanagh, Eoin C; Eustace, Stephen J

    2010-03-01

    The evaluation of muscle diseases has traditionally integrated clinical with biochemical findings, occasionally resorting to muscle biopsy. This article reviews the role and imaging appearances of muscle diseases at MRI, specifically emphasising the role of WBMRI in global assessment of muscle abnormality, and in particular its role in determining distribution and extent of muscle abnormality.

  12. Muscle insulin sensitivity and glucose metabolism are controlled by the intrinsic muscle clock

    DEFF Research Database (Denmark)

    Dyar, Kenneth A.; Ciciliot, Stefano; Wright, Lauren E.;

    2014-01-01

    Circadian rhythms control metabolism and energy homeostasis, but the role of the skeletal muscle clock has never been explored. We generated conditional and inducible mouse lines with muscle-specific ablation of the core clock gene Bmal1. Skeletal muscles from these mice showed impaired insulin-s...

  13. Improved identification of dystonic cervical muscles via abnormal muscle activity during isometric contractions

    NARCIS (Netherlands)

    De Bruijn, E.; Nijmeijer, S. W. R.; Forbes, P. A.; Koelman, J. H. T. M.; van der Helm, F. C. T.; Tijssen, M. A. J.; Happee, R.

    2015-01-01

    Background: The preferred treatment for cervical dystonia (CD) is injection of botulinum toxin in the dystonic muscles. Unfortunately, in the absence of reliable diagnostic methods it can be difficult to discriminate dystonic muscles from healthy muscles acting in compensation. We investigated if dy

  14. Improved identification of dystonic cervical muscles via abnormal muscle activity during isometric contractions

    NARCIS (Netherlands)

    De Bruijn, E; Nijmeijer, S W R; Forbes, P A; Koelman, J H T M; van der Helm, F C T; Tijssen, M A J; Happee, R

    2015-01-01

    BACKGROUND: The preferred treatment for cervical dystonia (CD) is injection of botulinum toxin in the dystonic muscles. Unfortunately, in the absence of reliable diagnostic methods it can be difficult to discriminate dystonic muscles from healthy muscles acting in compensation. We investigated if dy

  15. Muscle mechanics; the effect of stretch and shortening on skeletal muscle force

    NARCIS (Netherlands)

    Meijer, Kenneth

    1998-01-01

    The aim of the present thesis was to study systematically the impact of history dependent effects in intact muscles. For this purpose, experiments were performed on in situ medial gastrocnemius (GM) and soleus (SOL) muscles of the rat. Furthermore, mathematical muscle models were developed that desc

  16. Regulation of skeletal muscle oxidative capacity and muscle mass by SIRT3

    Science.gov (United States)

    We have previously reported that the expression of mitochondrial deacetylase SIRT3 is high in the slow oxidative muscle and that the expression of muscle SIRT3 level is increased by dietary restriction or exercise training. To explore the function of SIRT3 in skeletal muscle, we report here the esta...

  17. Effect of muscle acidity on muscle metabolism and fatigue during intense exercise in man

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Madsen, K.; Kiens, Bente;

    1996-01-01

    (kg wet weight)-1 min-1). The rate of muscle glycogen breakdown was the same in C and HL (8.1 +/- 1.2 vs. 8.2 +/- 1.0 mmol (kg wet weight)-1 min-1). 5. The present data suggest that elevated muscle acidity does not reduce muscle glycogenolysis/glycolysis and is not the only cause of fatigue during...

  18. Muscle fiber and motor unit behavior in the longest human skeletal muscle.

    Science.gov (United States)

    Harris, A John; Duxson, Marilyn J; Butler, Jane E; Hodges, Paul W; Taylor, Janet L; Gandevia, Simon C

    2005-09-14

    The sartorius muscle is the longest muscle in the human body. It is strap-like, up to 600 mm in length, and contains five to seven neurovascular compartments, each with a neuromuscular endplate zone. Some of its fibers terminate intrafascicularly, whereas others may run the full length of the muscle. To assess the location and timing of activation within motor units of this long muscle, we recorded electromyographic potentials from multiple intramuscular electrodes along sartorius muscle during steady voluntary contraction and analyzed their activity with spike-triggered averaging from a needle electrode inserted near the proximal end of the muscle. Approximately 30% of sartorius motor units included muscle fibers that ran the full length of the muscle, conducting action potentials at 3.9 +/- 0.1 m/s. Most motor units were innervated within a single muscle endplate zone that was not necessarily near the midpoint of the fiber. As a consequence, action potentials reached the distal end of a unit as late as 100 ms after initiation at an endplate zone. Thus, contractile activity is not synchronized along the length of single sartorius fibers. We postulate that lateral transmission of force from fiber to endomysium and a wide distribution of motor unit endplates along the muscle are critical for the efficient transmission of force from sarcomere to tendon and for the prevention of muscle injury caused by overextension of inactive regions of muscle fibers.

  19. Objective Evaluation of Muscle Strength in Infants with Hypotonia and Muscle Weakness

    Science.gov (United States)

    Reus, Linda; van Vlimmeren, Leo A.; Staal, J. Bart; Janssen, Anjo J. W. M.; Otten, Barto J.; Pelzer, Ben J.; Nijhuis-van der Sanden, Maria W. G.

    2013-01-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17…

  20. Comparison between muscle activation measured by electromyography and muscle thickness measured using ultrasonography for effective muscle assessment.

    Science.gov (United States)

    Kim, Chang-Yong; Choi, Jong-Duk; Kim, Suhn-Yeop; Oh, Duck-Won; Kim, Jin-Kyung; Park, Ji-Whan

    2014-10-01

    In this study, we aimed to compare the intrarater reliability and validity of muscle thickness measured using ultrasonography (US) and muscle activity via electromyography (EMG) during manual muscle testing (MMT) of the external oblique (EO) and lumbar multifidus (MF) muscles. The study subjects were 30 healthy individuals who underwent MMT at different grades. EMG was used to measure the muscle activity in terms of ratio to maximum voluntary contraction (MVC) and root mean square (RMS) metrics. US was used to measure the raw muscle thickness, the ratio of muscle thickness at MVC, and the ratio of muscle thickness at rest. One examiner performed measurements on each subject in 3 trials. The intrarater reliabilities of the % MVC RMS and raw RMS metrics for EMG and the % MVC thickness metrics for US were excellent (ICC=0.81-0.98). There was a significant difference between all the grades measured using the % MVC thickness metric (pEMG measurement methods than with the others (r=0.51-0.61). Our findings suggest that the % MVC thickness determined by US was the most sensitive of all methods for assessing the MMT grade.

  1. In Graves' disease, increased muscle tension and reduced elasticity of affected muscles is primarily caused by active muscle contraction

    NARCIS (Netherlands)

    H.J. Simonsz (Huib); G. Kommerell (Guntram)

    1989-01-01

    textabstractIn three patients with Graves' disease of recent onset, length-tension diagrams were made during surgery for squint under eyedrop anesthesia, while the other eye looked ahead, into the field of action, or out of the field of action of the muscle that was measured. The affected muscles we

  2. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    Science.gov (United States)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-01-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature (P < 0.05). This result indicated that repeated local muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  3. Bilateral Tensor Fasciae Suralis Muscles in a Cadaver with Unilateral Accessory Flexor Digitorum Longus Muscle

    Directory of Open Access Journals (Sweden)

    Logan S. W. Bale

    2017-01-01

    Full Text Available Muscle variants are routinely encountered in the dissection laboratory and in clinical practice and therefore anatomists and clinicians need to be aware of their existence. Here we describe two different accessory muscles identified while performing educational dissection of a 51-year-old male cadaver. Tensor fasciae suralis, a rare muscle variant, was identified bilaterally and accessory flexor digitorum longus, a more common muscle variant, was present unilaterally. Tensor fasciae suralis and accessory flexor digitorum longus are clinically relevant muscle variants. To our knowledge, the coexistence of tensor fasciae suralis and accessory flexor digitorum longus in the same individual has not been reported in either cadaveric or imaging studies.

  4. Pericranial muscle dysfunction in primary headache and its correction

    Directory of Open Access Journals (Sweden)

    Vera Valentinovna Osipova

    2010-01-01

    comorbid association, and the involvement of muscle tension in the pathophysiology of TTN. Approaches to treating muscle tension in patients with primary headache disorders are discussed and a role of myorelaxants in the correction of muscle dysfunction is emphasized.

  5. Proteomic signature of muscle atrophy in rainbow trout

    Science.gov (United States)

    Muscle deterioration arises as a physiological response to elevated energetic demands of fish sexual maturation and spawning. Previously, we used this model to characterize the transcriptomic mechanisms associated with muscle degradation in fish and identified potential biological markers of muscle...

  6. Genetics Home Reference: myostatin-related muscle hypertrophy

    Science.gov (United States)

    ... Conditions myostatin-related muscle hypertrophy myostatin-related muscle hypertrophy Enable Javascript to view the expand/collapse boxes. ... Open All Close All Description Myostatin-related muscle hypertrophy is a rare condition characterized by reduced body ...

  7. Regulation of Metabolic Signaling in Human Skeletal Muscle

    DEFF Research Database (Denmark)

    Albers, Peter Hjorth

    sensitivity in type I muscle fibers possibly reflects a superior effect of insulin on metabolic signaling compared to type II muscle fibers. This was investigated in the present thesis by examining muscle biopsies from lean and obese healthy subjects as well as patients with type 2 diabetes. From these muscle...... enzymes. Skeletal muscle consists of thousands of muscle fibers. These fibers can roughly be classified into type I and type II muscle fibers. The overall aim of this PhD thesis was to investigate the effect of insulin and exercise on human muscle fiber type specific metabolic signaling. The importance...... of human type I muscle fibers is illustrated by the finding of a positive correlation between the relative distribution of type I fibers in the muscle and whole-body insulin sensitivity. This suggests, that type I muscle fibers are more insulin sensitive than type II muscle fibers. Improved insulin...

  8. The Human Skeletal Muscle Proteome Project

    DEFF Research Database (Denmark)

    Gonzalez-Freire, Marta; Semba, Richard D.; Ubaida-Mohien, Ceereena

    2017-01-01

    Skeletal muscle is a large organ that accounts for up to half the total mass of the human body. A progressive decline in muscle mass and strength occurs with ageing and in some individuals configures the syndrome of ‘sarcopenia’, a condition that impairs mobility, challenges autonomy, and is a ri...

  9. Autonomic Modification of Intestinal Smooth Muscle Contractility

    Science.gov (United States)

    Montgomery, Laura E. A.; Tansey, Etain A.; Johnson, Chris D.; Roe, Sean M.; Quinn, Joe G.

    2016-01-01

    Intestinal smooth muscle contracts rhythmically in the absence of nerve and hormonal stimulation because of the activity of pacemaker cells between and within the muscle layers. This means that the autonomic nervous system modifies rather than initiates intestinal contractions. The practical described here gives students an opportunity to observe…

  10. Regulation of skeletal muscle glycogenolysis during exercise

    DEFF Research Database (Denmark)

    Hargreaves, M; Richter, Erik

    1988-01-01

    Muscle-glycogen breakdown during exercise is influenced by both local and systemic factors. Contractions per se increase glycogenolysis via a calcium-induced, transient increase in the activity of phosphorylase a, and probably also via increased concentrations of Pi. In fast-twitch muscle, increa...

  11. Sleeve Muscle Actuator: Concept and Prototype Demonstration

    Institute of Scientific and Technical Information of China (English)

    Tad Driver; Xiangrong Shen

    2013-01-01

    This paper presents the concept and prototype demonstration results of a new sleeve muscle actuator,which provides a significantly improved performance through a fundamental structural change to the traditional pneumatic muscle.Specifically,the sleeve muscle incorporates a cylindrical insert to the center of the pneumatic muscle,and thus eliminates the central portion of the intemal volume.Through the analysis of the actuation mechanism,it is shown that the sleeve muscle is able to provide a consistent increase of force capacity over the entire range of motion.Furthermore,the sleeve muscle provides a significant energy saving effect,as a result of the reduced internal volume as well as the enhance force capacity.To demonstrate this new concept,a sleeve muscle prototype was designed and fabricated.Experiments conducted on the prototype verified the improvement in the force capacity and demonstrated a significant energy saving effect (20%-37%).Finally,as the future work on this new concept,the paper presents a new robotic elbow design actuated with the proposed sleeve muscle.This unique design is expected to provide a highly compact and powerful actuation approach for robotic systems.

  12. Bio-inspired Hybrid Carbon Nanotube Muscles

    Science.gov (United States)

    Kim, Tae Hyeob; Kwon, Cheong Hoon; Lee, Changsun; An, Jieun; Phuong, Tam Thi Thanh; Park, Sun Hwa; Lima, Márcio D.; Baughman, Ray H.; Kang, Tong Mook; Kim, Seon Jeong

    2016-05-01

    There has been continuous progress in the development for biomedical engineering systems of hybrid muscle generated by combining skeletal muscle and artificial structure. The main factor affecting the actuation performance of hybrid muscle relies on the compatibility between living cells and their muscle scaffolds during cell culture. Here, we developed a hybrid muscle powered by C2C12 skeletal muscle cells based on the functionalized multi-walled carbon nanotubes (MWCNT) sheets coated with poly(3,4-ethylenedioxythiophene) (PEDOT) to achieve biomimetic actuation. This hydrophilic hybrid muscle is physically durable in solution and responds to electric field stimulation with flexible movement. Furthermore, the biomimetic actuation when controlled by electric field stimulation results in movement similar to that of the hornworm by patterned cell culture method. The contraction and relaxation behavior of the PEDOT/MWCNT-based hybrid muscle is similar to that of the single myotube movement, but has faster relaxation kinetics because of the shape-maintenance properties of the freestanding PEDOT/MWCNT sheets in solution. Our development provides the potential possibility for substantial innovation in the next generation of cell-based biohybrid microsystems.

  13. Sympathetic actions on the skeletal muscle.

    Science.gov (United States)

    Roatta, Silvestro; Farina, Dario

    2010-01-01

    The sympathetic nervous system (SNS) modulates several functions in skeletal muscle fibers, including metabolism, ionic transport across the membrane, and contractility. These actions, together with the sympathetic control of other organ systems, support intense motor activity. However, some SNS actions on skeletal muscles may not always be functionally advantageous. Implications for motor control and sport performance are discussed.

  14. Calpain 3 is important for muscle regeneration

    DEFF Research Database (Denmark)

    Hauerslev, Simon; Sveen, Marie-Louise; Duno, Morten;

    2012-01-01

    Limb girdle muscular dystrophy (LGMD) type 2A is caused by mutations in the CAPN3 gene and complete lack of functional calpain 3 leads to the most severe muscle wasting. Calpain 3 is suggested to be involved in maturation of contractile elements after muscle degeneration. The aim of this study...

  15. Neuromuscular imaging in inherited muscle diseases

    Energy Technology Data Exchange (ETDEWEB)

    Wattjes, Mike P. [VU University Medical Center, Department of Radiology, De Boelelaan 1117, HV, Amsterdam (Netherlands); Kley, Rudolf A. [Klinken Bergmannsheil, Ruhr-University, Department of Neurology, Neuromuscular Centre Ruhrgebiet, Bochum (Germany); Fischer, Dirk [University Hospital of Basel, Department of Neurology, Basel (Switzerland); University Children' s Hospital Basel, Department of Neuropaediatrics, Basel (Switzerland)

    2010-10-15

    Driven by increasing numbers of newly identified genetic defects and new insights into the field of inherited muscle diseases, neuromuscular imaging in general and magnetic resonance imaging (MRI) in particular are increasingly being used to characterise the severity and pattern of muscle involvement. Although muscle biopsy is still the gold standard for the establishment of the definitive diagnosis, muscular imaging is an important diagnostic tool for the detection and quantification of dystrophic changes during the clinical workup of patients with hereditary muscle diseases. MRI is frequently used to describe muscle involvement patterns, which aids in narrowing of the differential diagnosis and distinguishing between dystrophic and non-dystrophic diseases. Recent work has demonstrated the usefulness of muscle imaging for the detection of specific congenital myopathies, mainly for the identification of the underlying genetic defect in core and centronuclear myopathies. Muscle imaging demonstrates characteristic patterns, which can be helpful for the differentiation of individual limb girdle muscular dystrophies. The aim of this review is to give a comprehensive overview of current methods and applications as well as future perspectives in the field of neuromuscular imaging in inherited muscle diseases. We also provide diagnostic algorithms that might guide us through the differential diagnosis in hereditary myopathies. (orig.)

  16. Future perspectives: pathogenesis of chronic muscle pain.

    Science.gov (United States)

    Staud, Roland

    2007-06-01

    Chronic painful muscle conditions include non-inflammatory and inflammatory illnesses. This review is focused on chronic non-inflammatory pain conditions such as myofascial pain syndrome (MPS) and fibromyalgia syndrome (FM), and will not discuss metabolic, genetic or inflammatory muscle diseases such as McArdle's disease, muscular dystrophy, polymyositis, dermatomyositis, or inclusion body myositis.

  17. Return to sport after muscle injury.

    Science.gov (United States)

    Wong, Stephanie; Ning, Anne; Lee, Carlin; Feeley, Brian T

    2015-06-01

    Skeletal muscle injuries are among the most common sports-related injuries that result in time lost from practice and competition. The cellular response to muscle injury can often result in changes made to the muscle fibers as well as the surrounding extracellular matrix during repair. This can negatively affect the force and range of the injured muscle even after the patient's return to play. Diagnosis of skeletal muscle injury involves both history and physical examinations; imaging modalities including ultrasound and magnetic resonance imaging (MRI) can also be used to assess the extent of injury. Current research is investigating potential methods, including clinical factors and MRI, by which to predict a patient's return to sports. Overall, function of acutely injured muscles seems to improve with time. Current treatment methods for skeletal muscle injuries include injections of steroids, anesthetics, and platelet-rich plasma (PRP). Other proposed methods involve inhibitors of key players in fibrotic pathways, such as transforming growth factor (TGF)-ß and angiotensin II, as well as muscle-derived stem cells.

  18. Asymmetry of Muscle Strength in Elite Athletes

    Science.gov (United States)

    Drid, Patrik; Drapsin, Miodrag; Trivic, Tatjana; Lukac, Damir; Obadov, Slavko; Milosevic, Zoran

    2009-01-01

    "Study aim": To determine muscle strength variables in elite judoists and wrestlers since thigh muscle strength and bilaterally balanced flexor-to-extensor ratio minimise injury risk and are desirable for achieving sport successes. "Material and methods": Judoists, wrestlers and untrained subjects, 10 each, were subjected to isokinetic strength…

  19. Addison's disease presenting with muscle spasm.

    Science.gov (United States)

    Bhattacharjee, Rana; Sharma, A; Rays, A; Thakur, I; Sarkar, D; Mandal, B; Mookerjee, S K; Chatterjee, S K; Chowdhury, Pradip Roy

    2013-09-01

    Primary hypoadrenalism has various causes and protean manifestation. We report a young female patient who presented with severe muscle spasm as her primary complaint. On evaluation she was found to be a case of Addison's disease secondary to adrenal tuberculosis. Her muscle spasm disappeared rapidly with replacement dose of glucocorticoid.

  20. Muscle activation patterns in posttraumatic neck pain

    NARCIS (Netherlands)

    Nederhand, Marcus Johannes

    2003-01-01

    As an important consequence of our research, we question the relevance of the criteria of the WAD injury severity classification system. We showed that the musculoskeletal signs in WAD grade II are not characterized by muscle spasm, (i.e. increase of muscle activity), but rather by a decrease in mus

  1. Changes following denervation to the masseter muscle

    Institute of Scientific and Technical Information of China (English)

    Lei Zhang

    2008-01-01

    BACKGROUND: Masseter muscle nerve is often injured in mandible osteotomy. What changes in food intake and masseter muscle will be brought after masseter muscle nerve injury?OBJECTIVE: This study was designed to selectively establish animal models of denervated masseter muscle and investigate the effects of severing masseter muscular nerve on masseter muscle and animal's food intake. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the Laboratory Animal Center, Nanfang Hospital, Southern Medical University from September to November 2005. MATERIALS: A total of 50 healthy, adult, SPF-grade, New Zealand rabbits, of both genders, were used to develop an animal model of selectively denervated masseter muscle.METHODS: Five rabbits were randomly selected as normal controls. According to various mutilation methods, the remaining animals were randomly divided into 3 experimental groups, with 15 rabbits in each group: masseter muscular neural stem denervated, masseter muscular neural superior branch-denervated, and masseter muscular neural inferior branch-denervated groups. Self-control comparison was performed on each animal. The right masseter muscle served as the experimental side, and the left masseter muscle served as the control side. In each group, 3 time points (2, 8, and 24 weeks post-surgery) were allotted for observation. MAIN OUTCOME MEASURES: At the pre-set time points, masseter muscular thickness was measured with a Logic 500 color Doppler ultrasonic diagnostic apparatus. Masseter muscle tissue was resected for hematoxylin eosin staining. Masseter muscular fiber diameter and area were measured with an optical microscope. Masseter muscle tissue was sectioned and nicotinamide adenine dinucleotide tetrazolium oxidoreductase (NADH-TR) and adenosine triphosphatase staining were performed. Following staining, the sections were quantitatively analyzed using an IBAS200 image analyzer.RESULTS: Post-surgery food intake: No abnormal

  2. Noninvasive analysis of human neck muscle function

    Science.gov (United States)

    Conley, M. S.; Meyer, R. A.; Bloomberg, J. J.; Feeback, D. L.; Dudley, G. A.

    1995-01-01

    STUDY DESIGN. Muscle use evoked by exercise was determined by quantifying shifts in signal relaxation times of T2-weighted magnetic resonance images. Images were collected at rest and after exercise at each of two intensities (moderate and intense) for each of four head movements: 1) extension, 2) flexion, 3) rotation, and 4) lateral flexion. OBJECTIVE. This study examined the intensity and pattern of neck muscle use evoked by various movements of the head. The results will help elucidate the pathophysiology, and thus methods for treating disorders of the cervical musculoskeletal system. SUMMARY OF BACKGROUND DATA. Exercise-induced contrast shifts in T2 has been shown to indicate muscle use during the activity. The noninvasive nature of magnetic resonance imaging appears to make it an ideal approach for studying the function of the complex neuromuscular system of the neck. METHODS. The extent of T2 increase was examined to gauge how intensely nine different neck muscles or muscle pairs were used in seven subjects. The absolute and relative cross-sectional area of muscle showing a shift in signal relaxation was assessed to infer the pattern of use among and within individual neck muscles or muscle pairs. RESULTS. Signal relaxation increased with exercise intensity for each head movement. The absolute and relative cross-sectional area of muscle showing a shift in signal relaxation also increased with exercise load. Neck muscles or muscle pairs extensively used to perform each head movement were: extension--semispinalis capitis and cervicis and splenius capitis; flexion--sternocleidomastoid and longus capitis and colli; rotation--splenius capitis, levator scapulae, scalenus, semispinalis capitis ipsilateral to the rotation, and sternocleidomastoid contralateral; and lateral flexion--sternocleidomastoid CONCLUSION. The results of this study, in part, agree with the purported functions of neck muscles derived from anatomic location. This also was true for the few

  3. Association of muscle hardness with muscle tension dynamics: a physiological property.

    Science.gov (United States)

    Murayama, Mitsuyoshi; Watanabe, Kotaro; Kato, Ryoko; Uchiyama, Takanori; Yoneda, Tsugutake

    2012-01-01

    This study aimed to investigate the relationship between muscle hardness and muscle tension in terms of length-tension relationship. A frog gastrocnemius muscle sample was horizontally mounted on the base plate inside a chamber and was stretched from 100 to 150% of the pre-length, in 5% increments. After each step of muscle lengthening, electrical field stimulation for induction of tetanus was applied using platinum-plate electrodes positioned on either side of the muscle submerged in Ringer's solution. The measurement of muscle hardness, i.e., applying perpendicular distortion, was performed whilst maintaining the plateau of passive and tetanic tension. The relationship between normalised tension and normalised muscle hardness was evaluated. The length-hardness diagram could be created from the modification with the length-tension diagram. It is noteworthy that muscle hardness was proportional to passive and total tension. Regression analysis revealed a significant correlation between muscle hardness and passive and total tension, with a significant positive slope (passive tension: r = 0.986, P hardness depends on muscle tension in most ranges of muscle length in the length-tension diagram.

  4. Epigenetic regulation of muscle phenotype and adaptation: a potential role in COPD muscle dysfunction.

    Science.gov (United States)

    Barreiro, Esther; Sznajder, Jacob I

    2013-05-01

    Quadriceps muscle dysfunction occurs in one-third of patients with chronic obstructive pulmonary disease (COPD) in very early stages of their condition, even prior to the development of airway obstruction. Among several factors, deconditioning and muscle mass loss are the most relevant contributing factors leading to this dysfunction. Moreover, epigenetics, defined as the process whereby gene expression is regulated by heritable mechanisms that do not affect DNA sequence, could be involved in the susceptibility to muscle dysfunction, pathogenesis, and progression. Herein, we review the role of epigenetic mechanisms in muscle development and adaptation to environmental factors such as immobilization and exercise, and their implications in the pathophysiology and susceptibility to muscle dysfunction in COPD. The epigenetic modifications identified so far include DNA methylation, histone acetylation and methylation, and non-coding RNAs such as microRNAs (miRNAs). In the present review, we describe the specific contribution of epigenetic mechanisms to the regulation of embryonic myogenesis, muscle structure and metabolism, immobilization, and exercise, and in muscles of COPD patients. Events related to muscle development and regeneration and the response to exercise and immobilization are tightly regulated by epigenetic mechanisms. These environmental factors play a key role in the outcome of muscle mass and function as well as in the susceptibility to muscle dysfunction in COPD. Future research remains to be done to shed light on the specific target pathways of miRNA function and other epigenetic mechanisms in the susceptibility, pathogenesis, and progression of COPD muscle dysfunction.

  5. Muscle activation of paraspinal muscles in different types of high heels during standing.

    Science.gov (United States)

    Han, Dongwook

    2015-01-01

    [Purpose] This study researched the effects of different types of high heels on the muscles surrounding the cervical spine, the thoracic spine, and the lumbar spine by analyzing muscle activation of the paraspinal muscles during standing while wearing high heels. The high heels were all of the same height: 8 cm. [Subjects and Methods] The 28 subjects in this experiment were females in their 20s with a foot size of 225-230 mm and a normal gait pattern. To measure the muscle activation of the paraspinal muscles, EMG electrodes were attached on the paraspinal muscles around C6, T7, and L5. The muscle activation during standing while wearing 8-cm-high wedge heels, setback heels, and French heels was then measured. The measurements were performed 3 times each, and the mean value was used for analysis. [Results] The levels of muscle activation of the paraspinal muscles induced by standing on wedge heels, setback heels, and French heels in the cervical and lumbar areas were significantly higher than those induced by standing on bare feet. But there was no significant difference according to the heel types. [Conclusion] The height of the heels presented a greater variable than the width of the heels on the muscle activation of paraspinal muscles. Therefore, wearing high heels is not recommended for those who have pain or functional problems in the cervical and/or lumbar spine.

  6. Changes in Predicted Muscle Coordination with Subject-Specific Muscle Parameters for Individuals after Stroke

    Directory of Open Access Journals (Sweden)

    Brian A. Knarr

    2014-01-01

    Full Text Available Muscle weakness is commonly seen in individuals after stroke, characterized by lower forces during a maximal volitional contraction. Accurate quantification of muscle weakness is paramount when evaluating individual performance and response to after stroke rehabilitation. The objective of this study was to examine the effect of subject-specific muscle force and activation deficits on predicted muscle coordination when using musculoskeletal models for individuals after stroke. Maximum force generating ability and central activation ratio of the paretic plantar flexors, dorsiflexors, and quadriceps muscle groups were obtained using burst superimposition for four individuals after stroke with a range of walking speeds. Two models were created per subject: one with generic and one with subject-specific activation and maximum isometric force parameters. The inclusion of subject-specific muscle data resulted in changes in the model-predicted muscle forces and activations which agree with previously reported compensation patterns and match more closely the timing of electromyography for the plantar flexor and hamstring muscles. This was the first study to create musculoskeletal simulations of individuals after stroke with subject-specific muscle force and activation data. The results of this study suggest that subject-specific muscle force and activation data enhance the ability of musculoskeletal simulations to accurately predict muscle coordination in individuals after stroke.

  7. Action of obestatin in skeletal muscle repair: stem cell expansion, muscle growth, and microenvironment remodeling.

    Science.gov (United States)

    Gurriarán-Rodríguez, Uxía; Santos-Zas, Icía; González-Sánchez, Jessica; Beiroa, Daniel; Moresi, Viviana; Mosteiro, Carlos S; Lin, Wei; Viñuela, Juan E; Señarís, José; García-Caballero, Tomás; Casanueva, Felipe F; Nogueiras, Rubén; Gallego, Rosalía; Renaud, Jean-Marc; Adamo, Sergio; Pazos, Yolanda; Camiña, Jesús P

    2015-06-01

    The development of therapeutic strategies for skeletal muscle diseases, such as physical injuries and myopathies, depends on the knowledge of regulatory signals that control the myogenic process. The obestatin/GPR39 system operates as an autocrine signal in the regulation of skeletal myogenesis. Using a mouse model of skeletal muscle regeneration after injury and several cellular strategies, we explored the potential use of obestatin as a therapeutic agent for the treatment of trauma-induced muscle injuries. Our results evidenced that the overexpression of the preproghrelin, and thus obestatin, and GPR39 in skeletal muscle increased regeneration after muscle injury. More importantly, the intramuscular injection of obestatin significantly enhanced muscle regeneration by simulating satellite stem cell expansion as well as myofiber hypertrophy through a kinase hierarchy. Added to the myogenic action, the obestatin administration resulted in an increased expression of vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor 2 (VEGFR2) and the consequent microvascularization, with no effect on collagen deposition in skeletal muscle. Furthermore, the potential inhibition of myostatin during obestatin treatment might contribute to its myogenic action improving muscle growth and regeneration. Overall, our data demonstrate successful improvement of muscle regeneration, indicating obestatin is a potential therapeutic agent for skeletal muscle injury and would benefit other myopathies related to muscle regeneration.

  8. Normal and pathologically altered oculomotoric muscles in CT picture

    Energy Technology Data Exchange (ETDEWEB)

    Kvicala, V.; Balakova, H. (Karlova Univ., Prague (Czechoslovakia). Fakulta Vseobecneho Lekarstvi)

    1984-03-01

    Computerized tomography reliably visualizes oculomotoric muscles, particularly in coronary projection. 21 patients were examined where computerized tomography of the orbit showed disorders of oculomotoric muscles. Thyreoprivic ophthalmopathy (8 patients) was manifest by non-symmetric irregular thickening of muscles, whose density was unhomogeneously higher. In acromegaly (3 patients) the thickening of the muscles was less, affecting all muscles to a similar degree. Inflammatory and tumorous processes always affected only one oculomotoric muscle.

  9. The expression of HSP in human skeletal muscle. Effects of muscle fiber phenotype and training background

    DEFF Research Database (Denmark)

    Folkesson, Mattias; Mackey, Abigail L; Langberg, Henning;

    2013-01-01

    AIM: Exercise-induced adaptations of skeletal muscle are related to training mode and can be muscle fibre type specific. This study aimed to investigate heat shock protein expression in type I and type II muscle fibres in resting skeletal muscle of subjects with different training backgrounds...... HSPs in human skeletal muscle is influenced by muscle fibre phenotype. The fibre type specific expression of HSP70 is influenced by resistance and endurance training whereas those of αB-crystallin and HSP27 are influenced only by endurance training suggesting the existence of a training......-modality specific action on the adaptive processes including heat shock proteins in human skeletal muscle. This article is protected by copyright. All rights reserved....

  10. Muscle force estimation with surface EMG during dynamic muscle contractions: a wavelet and ANN based approach.

    Science.gov (United States)

    Bai, Fengjun; Chew, Chee-Meng

    2013-01-01

    Human muscle force estimation is important in biomechanics studies, sports and assistive devices fields. Therefore, it is essential to develop an efficient algorithm to estimate force exerted by muscles. The purpose of this study is to predict force/torque exerted by muscles under dynamic muscle contractions based on continuous wavelet transform (CWT) and artificial neural networks (ANN) approaches. Mean frequency (MF) of the surface electromyography (EMG) signals power spectrum was calculated from CWT. ANN models were trained to derive the MF-force relationships from the subset of EMG signals and the measured forces. Then we use the networks to predict the individual muscle forces for different muscle groups. Fourteen healthy subjects (10 males and 4 females) were voluntarily recruited in this study. EMG signals were collected from the biceps brachii, triceps, hamstring and quadriceps femoris muscles to evaluate the proposed method. Root mean square errors (RMSE) and correlation coefficients between the predicted forces and measured actual forces were calculated.

  11. Neural compensation, muscle load distribution and muscle function in control of biped models

    Science.gov (United States)

    Bavarian, B.

    Three aspects of the neuromuscular control of muscle actuators in biped movements were studied: neural compensation, muscle load distribution, and muscle function. A block diagram of a neural control circuit model of the control nervous system is presented. Based on this block diagram a circuit comprised of a dynamic compensator, an inverse plant, and pre-programmed reference trajectory generators is proposed for control of a general n-link biped model. This circuit is used to study the postural stability and point-to-point voluntary movement of a two-link planar biped with two pairs of muscle models. The muscle load distribution, relevant to functional electrical stimulation of paraplegic patients for restoration of limited motor function, is considered. A quantitative analysis of the local controllability of a two-link planar biped model incorporating six major muscles of the lower extremities is presented. A model of the muscle for the lower extremities is presented.

  12. Spontaneous calcium transients manifest in the regenerating muscle and are necessary for skeletal muscle replenishment.

    Science.gov (United States)

    Tu, Michelle Kim; Borodinsky, Laura Noemi

    2014-07-01

    Tissue regeneration entails replenishing of damaged cells, appropriate cell differentiation and inclusion of regenerated cells into functioning tissues. In adult humans, the capacity of the injured spinal cord and muscle to self-repair is limited. In contrast, the amphibian larva can regenerate its tail after amputation with complete recovery of muscle, notochord and spinal cord. The cellular and molecular mechanisms underlying this phenomenon are still unclear. Here we show that upon injury muscle cell precursors exhibit Ca(2+) transients that depend on Ca(2+) release from ryanodine receptor-operated stores. Blockade of these transients impairs muscle regeneration. Furthermore, inhibiting Ca(2+) transients in the regenerating tail prevents the activation and proliferation of muscle satellite cells, which results in deficient muscle replenishment. These findings suggest that Ca(2+)-mediated activity is critical for the early stages of muscle regeneration, which may lead to developing effective therapies for tissue repair.

  13. Muscle fibre type and aetiology of obesity.

    Science.gov (United States)

    Wade, A J; Marbut, M M; Round, J M

    1990-04-07

    Proportions of slow (type 1) muscle fibres of the vastus lateralis and percentage body fat were measured in 11 healthy sedentary men. The proportion of slow muscle fibres was inversely related to fatness; at least 40% of the variability in fatness may be related to variation in muscle fibre type. Metabolic evidence in 50 men, provided by the respiratory exchange ratio (RER) during cycle ergometry, indicated that fatter men (or, in the subset of 11 men, those with a low proportion of slow muscle fibres) combusted less fat during work at 100 W than did lean men (or those with a high proportion of slow fibres). The effects of fitness and of body size were excluded in the analysis. The evidence supports the hypothesis that muscle fibre type is an aetiological factor for obesity.

  14. Intraurethral Injection of Autologous Minced Skeletal Muscle

    DEFF Research Database (Denmark)

    Gräs, Søren; Klarskov, Niels; Lose, Gunnar

    2014-01-01

    PURPOSE: Intraurethral injection of in vitro expanded autologous skeletal muscle derived cells is a new regenerative therapy for stress urinary incontinence. We examined the efficacy and safety of a simpler alternative strategy using freshly harvested, minced autologous skeletal muscle tissue...... with its inherent content of regenerative cells. MATERIALS AND METHODS: A total of 20 and 15 women with uncomplicated and complicated stress urinary incontinence, respectively, received intraurethral injections of minced autologous skeletal muscle tissue and were followed for 1 year. Efficacy was assessed...... noted. CONCLUSIONS: Intraurethral injection of minced autologous muscle tissue is a simple surgical procedure that appears safe and moderately effective in women with uncomplicated stress urinary incontinence. It compares well to a more complicated regenerative strategy using in vitro expanded muscle...

  15. Exercise in muscle glycogen storage diseases

    DEFF Research Database (Denmark)

    Preisler, Nicolai Rasmus; Haller, Ronald G; Vissing, John

    2015-01-01

    Glycogen storage diseases (GSD) are inborn errors of glycogen or glucose metabolism. In the GSDs that affect muscle, the consequence of a block in skeletal muscle glycogen breakdown or glucose use, is an impairment of muscular performance and exercise intolerance, owing to 1) an increase in glyco......Glycogen storage diseases (GSD) are inborn errors of glycogen or glucose metabolism. In the GSDs that affect muscle, the consequence of a block in skeletal muscle glycogen breakdown or glucose use, is an impairment of muscular performance and exercise intolerance, owing to 1) an increase...... exercise program has the potential to improve general health and fitness and improve quality of life, if executed properly. In this review, we describe skeletal muscle substrate use during exercise in GSDs, and how blocks in metabolic pathways affect exercise tolerance in GSDs. We review the studies...

  16. Increased muscle glucose uptake during contractions

    DEFF Research Database (Denmark)

    Ploug, Thorkil; Galbo, H; Richter, E A

    1984-01-01

    We reinvestigated the prevailing concept that muscle contractions only elicit increased muscle glucose uptake in the presence of a so-called "permissive" concentration of insulin (Berger et al., Biochem. J. 146: 231-238, 1975; Vranic and Berger, Diabetes 28: 147-163, 1979). Hindquarters from rats...... in severe ketoacidosis were perfused with a perfusate containing insulin antiserum. After 60 min perfusion, electrical stimulation increased glucose uptake of the contracting muscles fivefold. Also, subsequent contractions increased glucose uptake in hindquarters from nondiabetic rats perfused for 1.5 h......-methylglucose uptake increased during contractions and glucose uptake was negative at rest and zero during contractions. An increase in muscle transport and uptake of glucose during contractions does not require the presence of insulin. Furthermore, glucose transport in contracting muscle may only increase if glycogen...

  17. Inflammation induced loss of skeletal muscle.

    Science.gov (United States)

    Londhe, Priya; Guttridge, Denis C

    2015-11-01

    Inflammation is an important contributor to the pathology of diseases implicated in skeletal muscle dysfunction. A number of diseases and disorders including inflammatory myopathies and Chronic Obstructive Pulmonary Disorder (COPD) are characterized by chronic inflammation or elevation of the inflammatory mediators. While these disease states exhibit different pathologies, all have in common the loss of skeletal muscle mass and a deregulated skeletal muscle physiology. Pro-inflammatory cytokines are key contributors to chronic inflammation found in many of these diseases. This section of the review focuses on some of the known inflammatory disorders like COPD, Rheumatoid Arthritis (RA) and inflammatory myopathies that display skeletal muscle atrophy and also provides the reader an overview of the mediators of inflammation, their signaling pathways, and mechanisms of action. This article is part of a Special Issue entitled "Muscle Bone Interactions".

  18. Experimental knee pain reduces muscle strength

    DEFF Research Database (Denmark)

    Henriksen, Marius; Rosager, Sara; Aaboe, Jens

    2011-01-01

    Pain is the principal symptom in knee pathologies and reduced muscle strength is a common observation among knee patients. However, the relationship between knee joint pain and muscle strength remains to be clarified. This study aimed at investigating the changes in knee muscle strength following...... experimental knee pain in healthy volunteers, and if these changes were associated with the pain intensities. In a crossover study, 18 healthy subjects were tested on 2 different days. Using an isokinetic dynamometer, maximal muscle strength in knee extension and flexion was measured at angular velocities 0....... Knee pain reduced the muscle strength by 5 to 15% compared to the control conditions (P strength was positively correlated to the pain intensity. Experimental knee pain significantly reduced knee extension...

  19. Human skeletal muscle releases leptin in vivo

    DEFF Research Database (Denmark)

    Wolsk, Emil; Grøndahl, Thomas Sahl; Pedersen, Bente Klarlund

    2012-01-01

    and adipose tissue leptin release in vivo. We recruited 16 healthy male human participants. Catheters were inserted into the femoral artery and vein draining skeletal muscle, as well as an epigastric vein draining the abdominal subcutaneous adipose tissue. By combining the veno-arterial differences in plasma......Leptin is considered an adipokine, however, cultured myocytes have also been found to release leptin. Therefore, as proof-of-concept we investigated if human skeletal muscle synthesized leptin by measuring leptin in skeletal muscle biopsies. Following this, we quantified human skeletal muscle...... leptin with measurements of blood flow, leptin release from both tissues was quantified. To induce changes in leptin, the participants were infused with either saline or adrenaline in normo-physiological concentrations. The presence of leptin in skeletal muscle was confirmed by western blotting. Leptin...

  20. Lactate oxidation in human skeletal muscle mitochondria

    DEFF Research Database (Denmark)

    Jacobs, Robert A; Meinild, Anne-Kristine; Nordsborg, Nikolai B

    2013-01-01

    Lactate is an important intermediate metabolite in human bioenergetics and is oxidized in many different tissues including the heart, brain, kidney, adipose tissue, liver, and skeletal muscle. The mechanism(s) explaining the metabolism of lactate in these tissues, however, remains unclear. Here, we...... analyze the ability of skeletal muscle to respire lactate by using an in situ mitochondrial preparation that leaves the native tubular reticulum and subcellular interactions of the organelle unaltered. Skeletal muscle biopsies were obtained from vastus lateralis muscle in 16 human subjects. Samples were...... of exogenous LDH failed to increase lactate-stimulated respiration (P = 1.0). The results further demonstrate that human skeletal muscle mitochondria cannot directly oxidize lactate within the mitochondrial matrix. Alternately, these data support previous claims that lactate is converted to pyruvate within...

  1. Muscle function and swimming in sharks.

    Science.gov (United States)

    Shadwick, R E; Goldbogen, J A

    2012-04-01

    The locomotor system in sharks has been investigated for many decades, starting with the earliest kinematic studies by Sir James Gray in the 1930s. Early work on axial muscle anatomy also included sharks, and the first demonstration of the functional significance of red and white muscle fibre types was made on spinal preparations in sharks. Nevertheless, studies on teleosts dominate the literature on fish swimming. The purpose of this article is to review the current knowledge of muscle function and swimming in sharks, by considering their morphological features related to swimming, the anatomy and physiology of the axial musculature, kinematics and muscle dynamics, and special features of warm-bodied lamnids. In addition, new data are presented on muscle activation in fast-starts. Finally, recent developments in tracking technology that provide insights into shark swimming performance in their natural environment are highlighted.

  2. Fish muscle: the exceptional case of Notothenioids.

    Science.gov (United States)

    Fernández, Daniel A; Calvo, Jorge

    2009-03-01

    Fish skeletal muscle is an excellent model for studying muscle structure and function, since it has a very well-structured arrangement with different fiber types segregated in the axial and pectoral fin muscles. The morphological and physiological characteristics of the different muscle fiber types have been studied in several teleost species. In fish muscle, fiber number and size varies with the species considered, limiting fish maximum final length due to constraints in metabolites and oxygen diffusion. In this work, we analyze some special characteristics of the skeletal muscle of the suborder Notothenioidei. They experienced an impressive radiation inside Antarctic waters, a stable and cold environment that could account for some of their special characteristics. The number of muscle fibers is very low, 12,700-164,000, in comparison to 550,000-1,200,000 in Salmo salar of similar sizes. The size of the fibers is very large, reaching 600 microm in diameter, while for example Salmo salar of similar sizes have fibers of 220 microm maximum diameter. Evolutionary adjustment in cell cycle length for working at low temperature has been shown in Harpagifer antarcticus (111 h at 0 degrees C), when compared to the closely related sub-Antarctic species Harpagifer bispinis (150 h at 5 degrees C). Maximum muscle fiber number decreases towards the more derived notothenioids, a trend that is more related to phylogeny than to geographical distribution (and hence water temperature), with values as low as 3,600 in Harpagifer bispinis. Mitochondria volume density in slow muscles of notothenioids is very high (reaching 0.56) and since maximal rates of substrate oxidation by mitochondria is not enhanced, at least in demersal notothenioids, volume density is the only means of overcoming thermal constraints on oxidative capacity. In brief, some characteristics of the muscles of notothenioids have an apparent phylogenetic component while others seem to be adaptations to low temperature.

  3. Effective force control by muscle synergies

    Directory of Open Access Journals (Sweden)

    Denise J Berger

    2014-04-01

    Full Text Available Muscle synergies have been proposed as a way for the central nervous system (CNS to simplify the generation of motor commands and they have been shown to explain a large fraction of the variation in the muscle patterns across a variety of conditions. However, whether human subjects are able to control forces and movements effectively with a small set of synergies has not been tested directly. Here we show that muscle synergies can be used to generate target forces in multiple directions with the same accuracy achieved using individual muscles. We recorded electromyographic (EMG activity from 13 arm muscles and isometric hand forces during a force reaching task in a virtual environment. From these data we estimated the force associated to each muscle by linear regression and we identified muscle synergies by non-negative matrix factorization. We compared trajectories of a virtual mass displaced by the force estimated using the entire set of recorded EMGs to trajectories obtained using 4 to 5 muscle synergies. While trajectories were similar, when feedback was provided according to force estimated from recorded EMGs (EMG-control on average trajectories generated with the synergies were less accurate. However, when feedback was provided according to recorded force (force-control we did not find significant differences in initial angle error and endpoint error. We then tested whether synergies could be used as effectively as individual muscles to control cursor movement in the force reaching task by providing feedback according to force estimated from the projection of the recorded EMGs into synergy space (synergy-control. Human subjects were able to perform the task immediately after switching from force-control to EMG-control and synergy-control and we found no differences between initial movement direction errors and endpoint errors in all control modes. These results indicate that muscle synergies provide an effective strategy for motor

  4. The origin of activity in the biceps brachii muscle during voluntary contractions of the contralateral elbow flexor muscles

    NARCIS (Netherlands)

    Zijdewind, Inge; Butler, Jane E.; Gandevia, Simon C.; Taylor, Janet L.

    2006-01-01

    During strong voluntary contractions, activity is not restricted to the target muscles. Other muscles, including contralateral muscles, often contract. We used transcranial magnetic stimulation (TMS) to analyse the origin of these unintended contralateral contractions (termed "associated" contractio

  5. Respiratory muscle training increases respiratory muscle strength and reduces respiratory complications after stroke: a systematic review

    Directory of Open Access Journals (Sweden)

    Kênia KP Menezes

    2016-07-01

    Full Text Available Question: After stroke, does respiratory muscle training increase respiratory muscle strength and/or endurance? Are any benefits carried over to activity and/or participation? Does it reduce respiratory complications? Design: Systematic review of randomised or quasi-randomised trials. Participants: Adults with respiratory muscle weakness following stroke. Intervention: Respiratory muscle training aimed at increasing inspiratory and/or expiratory muscle strength. Outcome measures: Five outcomes were of interest: respiratory muscle strength, respiratory muscle endurance, activity, participation and respiratory complications. Results: Five trials involving 263 participants were included. The mean PEDro score was 6.4 (range 3 to 8, showing moderate methodological quality. Random-effects meta-analyses showed that respiratory muscle training increased maximal inspiratory pressure by 7 cmH2O (95% CI 1 to 14 and maximal expiratory pressure by 13 cmH2O (95% CI 1 to 25; it also decreased the risk of respiratory complications (RR 0.38, 95% CI 0.15 to 0.96 compared with no/sham respiratory intervention. Whether these effects carry over to activity and participation remains uncertain. Conclusion: This systematic review provided evidence that respiratory muscle training is effective after stroke. Meta-analyses based on five trials indicated that 30 minutes of respiratory muscle training, five times per week, for 5 weeks can be expected to increase respiratory muscle strength in very weak individuals after stroke. In addition, respiratory muscle training is expected to reduce the risk of respiratory complications after stroke. Further studies are warranted to investigate whether the benefits are carried over to activity and participation. Registration: PROSPERO (CRD42015020683. [Menezes KKP, Nascimento LR, Ada L, Polese JC, Avelino PR, Teixeira-Salmela LF (2016 Respiratory muscle training increases respiratory muscle strength and reduces respiratory

  6. Evaluating Swallowing Muscles Essential for Hyolaryngeal Elevation by Using Muscle Functional Magnetic Resonance Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, William G., E-mail: bp1@bu.edu [Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts (United States); Hindson, David F. [Department of Radiology, Boston Medical Center, Boston, Massachusetts (United States); Langmore, Susan E. [Department of Otolaryngology, Boston Medical Center, Boston, Massachusetts (United States); Speech and Hearing Sciences, Boston University, Boston, Massachusetts (United States); Zumwalt, Ann C. [Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts (United States)

    2013-03-01

    Purpose: Reduced hyolaryngeal elevation, a critical event in swallowing, is associated with radiation therapy. Two muscle groups that suspend the hyoid, larynx, and pharynx have been proposed to elevate the hyolaryngeal complex: the suprahyoid and longitudinal pharyngeal muscles. Thought to assist both groups is the thyrohyoid, a muscle intrinsic to the hyolaryngeal complex. Intensity modulated radiation therapy guidelines designed to preserve structures important to swallowing currently exclude the suprahyoid and thyrohyoid muscles. This study used muscle functional magnetic resonance imaging (mfMRI) in normal healthy adults to determine whether both muscle groups are active in swallowing and to test therapeutic exercises thought to be specific to hyolaryngeal elevation. Methods and Materials: mfMRI data were acquired from 11 healthy subjects before and after normal swallowing and after swallowing exercise regimens (the Mendelsohn maneuver and effortful pitch glide). Whole-muscle transverse relaxation time (T2 signal, measured in milliseconds) profiles of 7 test muscles were used to evaluate the physiologic response of each muscle to each condition. Changes in effect size (using the Cohen d measure) of whole-muscle T2 profiles were used to determine which muscles underlie swallowing and swallowing exercises. Results: Post-swallowing effect size changes (where a d value of >0.20 indicates significant activity during swallowing) for the T2 signal profile of the thyrohyoid was a d value of 0.09; a d value of 0.40 for the mylohyoid, 0.80 for the geniohyoid, 0.04 for the anterior digastric, and 0.25 for the posterior digastric-stylohyoid in the suprahyoid muscle group; and d values of 0.47 for the palatopharyngeus and 0.28 for the stylopharyngeus muscles in the longitudinal pharyngeal muscle group. The Mendelsohn maneuver and effortful pitch glide swallowing exercises showed significant effect size changes for all muscles tested, except for the thyrohyoid. Conclusions

  7. Segmental fibre type composition of the rat iliopsoas muscle.

    Science.gov (United States)

    Vlahovic, Hrvoje; Bazdaric, Ksenija; Marijancic, Verner; Soic-Vranic, Tamara; Malnar, Daniela; Arbanas, Juraj

    2017-01-18

    The iliopsoas of the rat is composed of two muscles - the psoas major muscle and the iliacus muscle. The psoas major muscle arises from all the lumbar vertebrae and the iliacus muscle from the fifth and sixth lumbar vertebrae and ilium. Their common insertion point is the lesser trochanter of the femur, and their common action is the lateral rotation of the femur and flexion of the hip joint. Unlike humans, the rat is a quadruped and only occasionally rises up on its hind legs. Therefore, it is expected that the fibre type composition of the rat iliopsoas muscle will be different than that of humans. The iliopsoas muscle of the rat is generally considered to be a fast muscle. However, previous studies of the fibre type composition of the rat psoas muscle showed different results. Moreover, very little is known about the composition of the rat iliacus muscle. The aim of our study was to examine the fibre type composition of the rat iliopsoas muscle in order to better understand the complex function of the listed muscle. The psoas major muscle was examined segmentally at four different levels of its origin. Type I, IIA, IIB and IIX muscle fibres were typed using monoclonal antibodies for myosin heavy chain identification. The percentage of muscle fibre types and muscle fibre cross-sectional areas were calculated. In our study we showed that in the rat iliopsoas muscle both the iliacus and the psoas major muscles had a predominance of fast muscle fibre types, with the highest percentage of the fastest IIB muscle fibres. Also, the IIB muscle fibres showed the largest cross-sectional area (CSA) in both muscles. As well, the psoas major muscle showed segmental differences of fibre type composition. Our results showed changes in percentages, as well as the CSAs of muscle fibre types in cranio-caudal direction. The most significant changes were visible in type IIB muscle fibres, where there was a decrease of percentages and the CSAs from the cranial towards the caudal part

  8. Botulinum Toxin Injections: A Treatment for Muscle Spasms

    Science.gov (United States)

    ... Your Health Resources Drugs, Procedures & Devices Procedures & Devices Botulinum Toxin Injections: A Treatment for Muscle Spasms Botulinum Toxin Injections: A Treatment for Muscle Spasms Drugs, Procedures & ...

  9. Muscle cramping over the diagnosis.

    Science.gov (United States)

    Lally, David R; Moster, Mark L; Foroozan, Rod

    2014-01-01

    A 44-year-old man with hypogonadism and adrenal insufficiency presented with transient blurred vision and halos around lights. Visual acuity was 20/20 in both eyes, and he had mild bilateral optic disk edema. Brain imaging was unremarkable, and lumbar puncture showed an opening pressure of 28.5 cm H2O with elevated protein. He also complained of muscle cramping, and magnetic resonance imaging of the spine demonstrated a heterogenous bone marrow signal. Bone survey showed a mixed lytic and sclerotic lesion within the left femur that proved to be a plasmacytoma. Serum protein electrophoresis had a small IgA spike, and plasma vascular endothelial growth factor (VEGF) was elevated. He was diagnosed with POEMS syndrome and underwent radiation to the plasmacytoma. Two years later he had a stable neuro-ophthalmologic exam with no signs of multiple myeloma. POEMS syndrome is a rare paraneoplastic syndrome from a plasma cell dyscrasia that may cause optic disk edema.

  10. In vivo passive mechanical behaviour of muscle fascicles and tendons in human gastrocnemius muscle-tendon units.

    Science.gov (United States)

    Herbert, Robert D; Clarke, Jillian; Kwah, Li Khim; Diong, Joanna; Martin, Josh; Clarke, Elizabeth C; Bilston, Lynne E; Gandevia, Simon C

    2011-11-01

    Ultrasound imaging was used to measure the length of muscle fascicles in human gastrocnemius muscles while the muscle was passively lengthened and shortened by moving the ankle. In some subjects the muscle belly 'buckled' at short lengths. When the gastrocnemius muscle-tendon unit was passively lengthened from its shortest in vivo length by dorsiflexing the ankle, increases in muscle-tendon length were not initially accompanied by increases in muscle fascicle lengths (fascicle length remained constant), indicating muscle fascicles were slack at short muscle-tendon lengths. The muscle-tendon length at which slack is taken up differs among fascicles: some fascicles begin to lengthen at very short muscle-tendon lengths whereas other fascicles remain slack over a large range of muscle-tendon lengths. This suggests muscle fascicles are progressively 'recruited' and contribute sequentially to muscle-tendon stiffness during passive lengthening of the muscle-tendon unit. Even above their slack lengths muscle fascicles contribute only a small part (tendon length. The contribution of muscle fascicles to muscle-tendon length increases with muscle length. The novelty of this work is that it reveals a previously unrecognised phenomenon (buckling at short lengths), posits a new mechanism of passive mechanical properties of muscle (recruitment of muscle fascicles), and confirms with high-resolution measurements that the passive compliance of human gastrocnemius muscle-tendon units is due largely to the tendon. It would be interesting to investigate if adaptations of passive properties of muscles are associated with changes in the distribution of muscle lengths at which fascicles fall slack.

  11. How sex hormones promote skeletal muscle regeneration.

    Science.gov (United States)

    Velders, Martina; Diel, Patrick

    2013-11-01

    Skeletal muscle regeneration efficiency declines with age for both men and women. This decline impacts on functional capabilities in the elderly and limits their ability to engage in regular physical activity and to maintain independence. Aging is associated with a decline in sex hormone production. Therefore, elucidating the effects of sex hormone substitution on skeletal muscle homeostasis and regeneration after injury or disuse is highly relevant for the aging population, where sarcopenia affects more than 30 % of individuals over 60 years of age. While the anabolic effects of androgens are well known, the effects of estrogens on skeletal muscle anabolism have only been uncovered in recent times. Hence, the purpose of this review is to provide a mechanistic insight into the regulation of skeletal muscle regenerative processes by both androgens and estrogens. Animal studies using estrogen receptor (ER) antagonists and receptor subtype selective agonists have revealed that estrogens act through both genomic and non-genomic pathways to reduce leukocyte invasion and increase satellite cell numbers in regenerating skeletal muscle tissue. Although animal studies have been more conclusive than human studies in establishing a role for sex hormones in the attenuation of muscle damage, data from a number of recent well controlled human studies is presented to support the notion that hormonal therapies and exercise induce added positive effects on functional measures and lean tissue mass. Based on the fact that aging human skeletal muscle retains the ability to adapt to exercise with enhanced satellite cell activation, combining sex hormone therapies with exercise may induce additive effects on satellite cell accretion. There is evidence to suggest that there is a 'window of opportunity' after the onset of a hypogonadal state such as menopause, to initiate a hormonal therapy in order to achieve maximal benefits for skeletal muscle health. Novel receptor subtype selective

  12. The effect of tonic contraction of the finger muscle on the motor cortical representation of the contracting adjacent muscle.

    Science.gov (United States)

    Jono, Yasutomo; Chujo, Yuta; Nomura, Yoshifumi; Tani, Keisuke; Nikaido, Yasutaka; Hatanaka, Ryota; Hiraoka, Koichi

    2015-01-01

    This study examined the effect of tonic contraction of the finger muscle on the motor cortical representation of the contracting adjacent muscle. A representation map of the motor evoked potential (MEP) in the first dorsal interosseous (FDI) and abductor digiti minimi (ADM) muscles was obtained with the subject at rest or during tonic contraction of the ADM muscle while the FDI muscle was tonically contracted. The center of gravity (COG) of the MEP map in the FDI muscle shifted medially during contraction of the ADM muscle. Motor cortical excitability in the motor cortical representation of the FDI muscle that did not overlap with the motor cortical representation of the ADM muscle was suppressed, but motor cortical excitability in the motor cortical representation of the FDI muscle overlapping with the motor cortical representation of the ADM muscle was not suppressed during contraction of the ADM muscle. The motor cortical representation of the FDI muscle not overlapping with the motor cortical representation of the ADM muscle was located lateral to that of the FDI muscle that did overlap with the motor cortical representation of the ADM muscle. Medial shift of the COG of the motor cortical representation of the contracting finger muscle induced by tonic contraction of the adjacent finger muscle must be due to suppression of motor cortical excitability in the lateral part of the representation, which is not shared by the adjacent representation.

  13. Muscle Fibre Types, Ubiquinone Content and Exercise Capacity in Hypertension and Effort Angina

    DEFF Research Database (Denmark)

    Karlsson, Jan; Diamant, Bertil; Folkers, Karl;

    1991-01-01

    Farmakologi, hypertension, IHD, skeletal muscle fibre composition, muscle coenzyme Q10, ischaemic heart disease, effort angina, muscle fibre lesion, muscle ubiquinone......Farmakologi, hypertension, IHD, skeletal muscle fibre composition, muscle coenzyme Q10, ischaemic heart disease, effort angina, muscle fibre lesion, muscle ubiquinone...

  14. Skeletal muscle regeneration after damage by needle penetration and trauma.

    Science.gov (United States)

    McGeachie, J K

    2000-10-01

    Skeletal muscles actually surround the dento-alveolar area. However, most dentists would be unaware that they damage skeletal muscle during routine procedures. Simple puncturing of buccinator muscle during an inferior alveolar block kills thousands of fibres. What happens to muscle fibres following such trauma? Pathology texts suggest that skeletal muscle does not regenerate and is replaced by fibrous scar tissue. However, for some decades it has been recognized that muscle fibres do in fact regenerate. In the early 1960s the "satellite" cell was discovered, lying between the muscle cell membrane and the external lamina. After 30 years of intensive research it has been clearly demonstrated that satellite cells are reserve mesenchyme cells which, once the adjacent muscle fibres are damaged, proliferate and provide a new population of young muscle cells, called "myoblasts". Myoblasts rapidly produce muscle specific proteins and fuse together in long chains, called "myotubes", which mature into typical muscle fibres.

  15. Reduced short-interval intracortical inhibition after eccentric muscle damage in human elbow flexor muscles.

    Science.gov (United States)

    Pitman, Bradley M; Semmler, John G

    2012-09-01

    The purpose of this study was to use paired-pulse transcranial magnetic stimulation (TMS) to examine the effect of eccentric exercise on short-interval intracortical inhibition (SICI) after damage to elbow flexor muscles. Nine young (22.5 ± 0.6 yr; mean ± SD) male subjects performed maximal eccentric exercise of the elbow flexor muscles until maximal voluntary contraction (MVC) force was reduced by ∼40%. TMS was performed before, 2 h after, and 2 days after exercise under Rest and Active (5% MVC) conditions with motor-evoked potentials (MEPs) recorded from the biceps brachii (BB) muscle. Peripheral electrical stimulation of the brachial plexus was used to assess maximal M-waves, and paired-pulse TMS with a 3-ms interstimulus interval was used to assess changes in SICI at each time point. The eccentric exercise resulted in a 34% decline in strength (P muscle strength (27%, P muscle soreness (P muscle damage. When the test MEP amplitudes were matched between sessions, we found that SICI was reduced by 27% in resting and 23% in active BB muscle 2 h after exercise. SICI recovered 2 days after exercise when muscle pain and soreness were present, suggesting that delayed onset muscle soreness from eccentric exercise does not influence SICI. The change in SICI observed 2 h after exercise suggests that eccentric muscle damage has widespread effects throughout the motor system that likely includes changes in motor cortex.

  16. Observational Study on the Occurrence of Muscle Spindles in Human Digastric and Mylohyoideus Muscles

    Directory of Open Access Journals (Sweden)

    Daniele Saverino

    2014-01-01

    Full Text Available Although the occurrence of muscle spindles (MS is quite high in most skeletal muscles of humans, few MS, or even absence, have been reported in digastric and mylohyoideus muscles. Even if this condition is generally accepted and quoted in many papers and books, observational studies are scarce and based on histological sections of a low number of specimens. The aim of the present study is to confirm previous data, assessing MS number in a sample of digastric and mylohyoideus muscles. We investigated 11 digastric and 6 mylohyoideus muscles from 13 donors. Muscle samples were embedded in paraffin wax, cross-sectioned in a rostrocaudal direction, and stained using haematoxylin-eosin. A mean of 5.1 ± 1.1 (range 3–7 MS was found in digastric muscles and mean of 0.5 ± 0.8 (range 0–2 in mylohyoideus muscles. A significant difference (P<0.001 was found with the control sample, confirming the correctness of the histological procedure. Our results support general belief that the absolute number of spindles is sparse in digastric and mylohyoideus muscles. External forces, such as food resistance during chewing or gravity, do not counteract jaw-opening muscles. It is conceivable that this condition gives them a limited proprioceptive importance and a reduced need for having specific receptors as MS.

  17. Endurance training facilitates myoglobin desaturation during muscle contraction in rat skeletal muscle.

    Science.gov (United States)

    Takakura, Hisashi; Furuichi, Yasuro; Yamada, Tatsuya; Jue, Thomas; Ojino, Minoru; Hashimoto, Takeshi; Iwase, Satoshi; Hojo, Tatsuya; Izawa, Tetsuya; Masuda, Kazumi

    2015-03-24

    At onset of muscle contraction, myoglobin (Mb) immediately releases its bound O2 to the mitochondria. Accordingly, intracellular O2 tension (PmbO2) markedly declines in order to increase muscle O2 uptake (mVO2). However, whether the change in PmbO2 during muscle contraction modulates mVO2 and whether the O2 release rate from Mb increases in endurance-trained muscles remain unclear. The purpose of this study was, therefore, to determine the effect of endurance training on O2 saturation of Mb (SmbO2) and PmbO2 kinetics during muscle contraction. Male Wistar rats were subjected to a 4-week swimming training (Tr group; 6 days per week, 30 min × 4 sets per day) with a weight load of 2% body mass. After the training period, deoxygenated Mb kinetics during muscle contraction were measured using near-infrared spectroscopy under hemoglobin-free medium perfusion. In the Tr group, the VmO2peak significantly increased by 32%. Although the PmbO2 during muscle contraction did not affect the increased mVO2 in endurance-trained muscle, the O2 release rate from Mb increased because of the increased Mb concentration and faster decremental rate in SmbO2 at the maximal twitch tension. These results suggest that the Mb dynamics during muscle contraction are contributing factors to faster VO2 kinetics in endurance-trained muscle.

  18. Muscle Damage and Its Relationship with Muscle Fatigue During a Half-Iron Triathlon

    Science.gov (United States)

    Coso, Juan Del; González-Millán, Cristina; Salinero, Juan José; Abián-Vicén, Javier; Soriano, Lidón; Garde, Sergio; Pérez-González, Benito

    2012-01-01

    Background To investigate the cause/s of muscle fatigue experienced during a half-iron distance triathlon. Methodology/Principal Findings We recruited 25 trained triathletes (36±7 yr; 75.1±9.8 kg) for the study. Before and just after the race, jump height and leg muscle power output were measured during a countermovement jump on a force platform to determine leg muscle fatigue. Body weight, handgrip maximal force and blood and urine samples were also obtained before and after the race. Blood myoglobin and creatine kinase concentrations were determined as markers of muscle damage. Results Jump height (from 30.3±5.0 to 23.4±6.4 cm; P0.05) but significantly correlated with myoglobin concentration (r = 0.65; P<0.001) and creatine kinase concentration (r = 0.54; P<0.001). Conclusions/significance During a half-iron distance triathlon, the capacity of leg muscles to produce force was notably diminished while arm muscle force output remained unaffected. Leg muscle fatigue was correlated with blood markers of muscle damage suggesting that muscle breakdown is one of the most relevant sources of muscle fatigue during a triathlon. PMID:22900101

  19. Muscle damage and its relationship with muscle fatigue during a half-iron triathlon.

    Directory of Open Access Journals (Sweden)

    Juan Del Coso

    Full Text Available BACKGROUND: To investigate the cause/s of muscle fatigue experienced during a half-iron distance triathlon. METHODOLOGY/PRINCIPAL FINDINGS: We recruited 25 trained triathletes (36±7 yr; 75.1±9.8 kg for the study. Before and just after the race, jump height and leg muscle power output were measured during a countermovement jump on a force platform to determine leg muscle fatigue. Body weight, handgrip maximal force and blood and urine samples were also obtained before and after the race. Blood myoglobin and creatine kinase concentrations were determined as markers of muscle damage. RESULTS: Jump height (from 30.3±5.0 to 23.4±6.4 cm; P0.05 but significantly correlated with myoglobin concentration (r = 0.65; P<0.001 and creatine kinase concentration (r = 0.54; P<0.001. CONCLUSIONS/SIGNIFICANCE: During a half-iron distance triathlon, the capacity of leg muscles to produce force was notably diminished while arm muscle force output remained unaffected. Leg muscle fatigue was correlated with blood markers of muscle damage suggesting that muscle breakdown is one of the most relevant sources of muscle fatigue during a triathlon.

  20. GLUT-3 expression in human skeletal muscle

    Science.gov (United States)

    Stuart, C. A.; Wen, G.; Peng, B. H.; Popov, V. L.; Hudnall, S. D.; Campbell, G. A.

    2000-01-01

    Muscle biopsy homogenates contain GLUT-3 mRNA and protein. Before these studies, it was unclear where GLUT-3 was located in muscle tissue. In situ hybridization using a midmolecule probe demonstrated GLUT-3 within all muscle fibers. Fluorescent-tagged antibody reacting with affinity-purified antibody directed at the carboxy-terminus demonstrated GLUT-3 protein in all fibers. Slow-twitch muscle fibers, identified by NADH-tetrazolium reductase staining, possessed more GLUT-3 protein than fast-twitch fibers. Electron microscopy using affinity-purified primary antibody and gold particle-tagged second antibody showed that the majority of GLUT-3 was in association with triads and transverse tubules inside the fiber. Strong GLUT-3 signals were seen in association with the few nerves that traversed muscle sections. Electron microscopic evaluation of human peripheral nerve demonstrated GLUT-3 within the axon, with many of the particles related to mitochondria. GLUT-3 protein was found in myelin but not in Schwann cells. GLUT-1 protein was not present in nerve cells, axons, myelin, or Schwann cells but was seen at the surface of the peripheral nerve in the perineurium. These studies demonstrated that GLUT-3 mRNA and protein are expressed throughout normal human skeletal muscle, but the protein is predominantly found in the triads of slow-twitch muscle fibers.

  1. Single muscle fiber adaptations with marathon training.

    Science.gov (United States)

    Trappe, Scott; Harber, Matthew; Creer, Andrew; Gallagher, Philip; Slivka, Dustin; Minchev, Kiril; Whitsett, David

    2006-09-01

    The purpose of this investigation was to characterize the effects of marathon training on single muscle fiber contractile function in a group of recreational runners. Muscle biopsies were obtained from the gastrocnemius muscle of seven individuals (22 +/- 1 yr, 177 +/- 3 cm, and 68 +/- 2 kg) before, after 13 wk of run training, and after 3 wk of taper. Slow-twitch myosin heavy chain [(MHC) I] and fast-twitch (MHC IIa) muscle fibers were analyzed for size, strength (P(o)), speed (V(o)), and power. The run training program led to the successful completion of a marathon (range 3 h 56 min to 5 h 35 min). Oxygen uptake during submaximal running and citrate synthase activity were improved (P 60% increase (P twitch and fast-twitch muscle fiber size but that it maintained or improved the functional profile of these fibers. A taper period before the marathon further improved the functional profile of the muscle, which was targeted to the fast-twitch muscle fibers.

  2. Matrix metalloproteinase imbalance in muscle disuse atrophy.

    Science.gov (United States)

    Giannelli, G; De Marzo, A; Marinosci, F; Antonaci, S

    2005-01-01

    Muscle atrophy commonly occurs as a consequence of prolonged muscle inactivity, as observed after cast immobilization, bed rest or space flights. The molecular mechanisms responsible for muscle atrophy are still unknown, but a role has been proposed for altered permeability of the sarcolemma and of the surrounding connective tissue. Matrix metallo-proteinases (MMPs) are a family of enzymes with proteolytic activity toward a number of extracellular matrix (ECM) components; they are inhibited by tissue inhibitors of MMPs (TIMPs). In a rat tail-suspension experimental model, we show that after fourteen days of non-weight bearing there is increased expression of MMP-2 in the atrophic soleus and gastrocnemius and decreased expression of TIMP-2. In the same experimental model the expression of Collagen I and Collagen IV, two main ECM components present in the muscles, was reduced and unevenly distributed in unloaded animals. The difference was more evident in the soleus than in the gastrocnemius muscle. This suggests that muscle disuse induces a proteolytic imbalance, which could be responsible for the breakdown of basal lamina structures such as Collagen I and Collagen IV, and that this leads to an altered permeability with consequent atrophy. In conclusion, an MMP-2/TIMP-2 imbalance could have a role in the mechanism underlying muscle disuse atrophy; more studies are needed to expand our molecular knowledge on this issue and to explore the possibility of targeting the proteolytic imbalance with MMP inhibitors.

  3. Jaw adductor muscles across lepidosaurs: a reappraisal.

    Science.gov (United States)

    Daza, Juan Diego; Diogo, Rui; Johnston, Peter; Abdala, Virginia

    2011-10-01

    The exact homologies of tetrapod jaw muscles remain unresolved, and this provides a barrier for phylogenetic analysis and tracing character evolution. Here, lepidosaur jaw muscles are surveyed using direct examination of species from 23 families and published descriptions of species from 10 families. A revised nomenclature is applied according to proposed homologies with Latimeria. Among lepidosaurs, variation was found in many aspects of jaw muscle anatomy. The superficial layers mm. levator and retractor anguli oris (LAO and RAO) are present in Sphenodon but not all squamates. The external jaw adductor muscles universally present in lepidosaurs are homologous with the main adductor muscle, A2, of Latimeria and include four layers: superficialis (A2-SUP), medialis (A2-M), profundus (A2-PRO), and posterior (A2-PVM). The A2-SUP appears divided in Agamidae, Gekkota, Xantusiidae, and Varanidae. The A2-M is layered lateromedial in lizards but anteroposterior in snakes. The names pseudotemporalis (PS) and pterygomandibularis (PTM) are recommended for subdivisions of the internal adductors of reptiles and amphibians, because the homology of this muscle with the A3' and A3 ″ of Latimeria remains inconclusive. The intramandibularis of lepidosaurs and Latimeria (A-ω) are homologous. The distribution of six jaw muscle characters was found to plot more parsimoniously on phylogenies based on morphological rather than and molecular data. Character mapping indicates that Squamata presents reduction in the divisions of the A2-M, Scincoidea presents reduction or loss of LAO, and two apomorphic features are found for the Gekkota.

  4. Muscle dissatisfaction in young adult men

    Directory of Open Access Journals (Sweden)

    Bulik Cynthia M

    2006-04-01

    Full Text Available Abstract Backround Appearance concerns are of increasing importance in young men's lives. We investigated whether muscle dissatisfaction is associated with psychological symptoms, dietary supplement or anabolic steroid use, or physical activity in young men. Methods As a part of a questionnaire assessment of health-related behaviors in the population-based FinnTwin16 study, we assessed factors associated with muscle dissatisfaction in 1245 men aged 22–27 using logistic regression models. Results Of men, 30% experienced high muscle dissatisfaction, while 12% used supplements/steroids. Of highly muscle-dissatisfied men, 21.5% used supplements/steroids. Mean body mass index, waist circumference, or leisure aerobic activity index did not differ between individuals with high/low muscle dissatisfaction. Muscle dissatisfaction was significantly associated with a psychological and psychosomatic problems, alcohol and drug use, lower height satisfaction, sedentary lifestyle, poor subjective physical fitness, and lower life satisfaction. Conclusion Muscle dissatisfaction and supplement/steroid use are relatively common, and are associated with psychological distress and markers of sedentary lifestyle.

  5. The differentiation and morphogenesis of craniofacial muscles.

    Science.gov (United States)

    Noden, Drew M; Francis-West, Philippa

    2006-05-01

    Unraveling the complex tissue interactions necessary to generate the structural and functional diversity present among craniofacial muscles is challenging. These muscles initiate their development within a mesenchymal population bounded by the brain, pharyngeal endoderm, surface ectoderm, and neural crest cells. This set of spatial relations, and in particular the segmental properties of these adjacent tissues, are unique to the head. Additionally, the lack of early epithelialization in head mesoderm necessitates strategies for generating discrete myogenic foci that may differ from those operating in the trunk. Molecular data indeed indicate dissimilar methods of regulation, yet transplantation studies suggest that some head and trunk myogenic populations are interchangeable. The first goal of this review is to present key features of these diversities, identifying and comparing tissue and molecular interactions regulating myogenesis in the head and trunk. Our second focus is on the diverse morphogenetic movements exhibited by craniofacial muscles. Precursors of tongue muscles partly mimic migrations of appendicular myoblasts, whereas myoblasts destined to form extraocular muscles condense within paraxial mesoderm, then as large cohorts they cross the mesoderm:neural crest interface en route to periocular regions. Branchial muscle precursors exhibit yet another strategy, establishing contacts with neural crest populations before branchial arch formation and maintaining these relations through subsequent stages of morphogenesis. With many of the prerequisite stepping-stones in our knowledge of craniofacial myogenesis now in place, discovering the cellular and molecular interactions necessary to initiate and sustain the differentiation and morphogenesis of these neglected craniofacial muscles is now an attainable goal.

  6. Mathematical analysis of a muscle architecture model.

    Science.gov (United States)

    Navallas, Javier; Malanda, Armando; Gila, Luis; Rodríguez, Javier; Rodríguez, Ignacio

    2009-01-01

    Modeling of muscle architecture, which aims to recreate mathematically the physiological structure of the muscle fibers and motor units, is a powerful tool for understanding and modeling the mechanical and electrical behavior of the muscle. Most of the published models are presented in the form of algorithms, without mathematical analysis of mechanisms or outcomes of the model. Through the study of the muscle architecture model proposed by Stashuk, we present the analytical tools needed to better understand these models. We provide a statistical description for the spatial relations between motor units and muscle fibers. We are particularly concerned with two physiological quantities: the motor unit fiber number, which we expect to be proportional to the motor unit territory area; and the motor unit fiber density, which we expect to be constant for all motor units. Our results indicate that the Stashuk model is in good agreement with the physiological evidence in terms of the expectations outlined above. However, the resulting variance is very high. In addition, a considerable 'edge effect' is present in the outer zone of the muscle cross-section, making the properties of the motor units dependent on their location. This effect is relevant when motor unit territories and muscle cross-section are of similar size.

  7. Calcium's Role in Mechanotransduction during Muscle Development

    Directory of Open Access Journals (Sweden)

    Tatiana Benavides Damm

    2014-01-01

    Full Text Available Mechanotransduction is a process where cells sense their surroundings and convert the physical forces in their environment into an appropriate response. Calcium plays a crucial role in the translation of such forces to biochemical signals that control various biological processes fundamental in muscle development. The mechanical stimulation of muscle cells may for example result from stretch, electric and magnetic stimulation, shear stress, and altered gravity exposure. The response, mainly involving changes in intracellular calcium concentration then leads to a cascade of events by the activation of downstream signaling pathways. The key calcium-dependent pathways described here include the nuclear factor of activated T cells (NFAT and mitogen-activated protein kinase (MAPK activation. The subsequent effects in cellular homeostasis consist of cytoskeletal remodeling, cell cycle progression, growth, differentiation, and apoptosis, all necessary for healthy muscle development, repair, and regeneration. A deregulation from the normal process due to disuse, trauma, or disease can result in a clinical condition such as muscle atrophy, which entails a significant loss of muscle mass. In order to develop therapies against such diseased states, we need to better understand the relevance of calcium signaling and the downstream responses to mechanical forces in skeletal muscle. The purpose of this review is to discuss in detail how diverse mechanical stimuli cause changes in calcium homeostasis by affecting membrane channels and the intracellular stores, which in turn regulate multiple pathways that impart these effects and control the fate of muscle tissue.

  8. Activation and intermuscular coherence of distal arm muscles during proximal muscle contraction.

    Science.gov (United States)

    Lee, Sang Wook; Landers, Katlin; Harris-Love, Michelle L

    2014-03-01

    In the human upper extremity (UE), unintended effects of proximal muscle activation on muscles controlling the hand could be an important aspect of motor control due to the necessary coordination of distal and proximal segments during functional activities. This study aimed to elucidate the effects of concurrent activation of elbow muscles on the coordination between hand muscles performing a grip task. Eleven healthy subjects performed precision grip tasks while a constant extension or flexion moment was applied to their elbow joints, inducing a sustained submaximal contraction of elbow muscles to counter the applied torque. Activation of four hand muscles was measured during each task condition using surface electromyography (EMG). When concurrent activation of elbow muscles was induced, significant changes in the activation levels of the hand muscles were observed, with greater effects on the extrinsic finger extensor (23.2 % increase under 30 % elbow extensor activation; p = 0.003) than extrinsic finger flexor (14.2 % increase under 30 % elbow flexor activation; p = 0.130). Elbow muscle activation also induced involuntary changes in the intrinsic thumb flexor activation (44.6 % increase under 30 % elbow extensor activation; p = 0.005). EMG-EMG coherence analyses revealed that elbow muscle activation significantly reduced intermuscular coherence between distal muscle pairs, with its greatest effects on coherence in the β-band (13-25 Hz) (average of 17 % decrease under 30 % elbow flexor activation). The results of this study provide evidence for involuntary, muscle-specific interactions between distal and proximal UE muscles, which may contribute to UE motor performance in health and disease.

  9. Generalization of Muscle Strength Capacities as Assessed From Different Variables, Tests, and Muscle Groups.

    Science.gov (United States)

    Cuk, Ivan; Prebeg, Goran; Sreckovic, Sreten; Mirkov, Dragan M; Jaric, Slobodan

    2017-02-01

    Cuk, I, Prebeg, G, Sreckovic, S, Mirkov, DM, and Jaric, S. Generalization of muscle strength capacities as assessed from different variables, tests, and muscle groups. J Strength Cond Res 31(2): 305-312, 2017-The muscle strength capacities to exert force under various movement conditions have been indiscriminately assessed from various strength tests and variables applied on different muscles. We tested the hypotheses that the distinctive strength capacities would be revealed (H1) through different strength tests, and (H2) through different strength variables. Alternatively, (H3) all strength variables independent of the selected test could depict the same strength capacity of the tested muscle. Sixty subjects performed both the standard strength test and the test of alternating contractions of 6 pairs of antagonistic muscles acting in different leg and arm joints. The dependent variables obtained from each test and muscle were the maximum isometric force and the rate of force development. A confirmatory principle component analysis set to 2 factors explained 31.9% of the total variance. The factor loadings discerned between the tested arm and leg muscles, but not between the strength tests and variables. An exploratory analysis applied on the same data revealed 6 factors that explained 60.1% of the total variance. Again, the individual factors were mainly loaded by different tests and variables obtained from the same pair of antagonistic muscles. Therefore, a comprehensive assessment of the muscle strength capacity of the tested individual should be based on a single strength test and variable obtained from a number of different muscles, than on a single muscle tested through different tests and variables. The selected muscles should act in different limbs and joints, while the maximum isometric force should be the variable of choice.

  10. Muscle: Bone ratios in beef rib sections.

    Science.gov (United States)

    Dolezal, H G; Murphey, C E; Smith, G C; Carpenter, Z L; McCartor, M

    1982-01-01

    Thirty-eight steers and thirty heifers (14 to 17 months of age, from F(1) Hereford × Brahman cows bred to Angus or Hereford bulls), were either forage-fed for 123 days on millet-bermudagrass pasture or grain-fed for 90 days on a high-concentrate diet and were then commercially slaughtered. Warm carcass weights ranged from 167·8 kg to 324·3 kg. At 24 h post mortem, Texas Agricultural Experiment Station personnel (1) assigned scores or took measurements on each carcass for all factors used in yield grading and quality grading, (2) measured the length of hind leg (HL) and carcass length (CL) and (3) assigned a score for carcass muscling (MS) and, as appropriate, made an adjusted longissimus muscle area (ALA) evaluation. The 9th-10th-11th rib section from one side of each carcass was physically separated into longissimus muscle, fat, 'other soft tissue' and bone and ether extract determinations of the longissimus muscle and 'other soft tissue' components were made and used to adjust the yields of each of these components to a fat-free basis. Muscle to bone ratios ranged from 2·38 to 4·37. With both age and carcass weight held constant, diet, breed and sex explained only 35·8% of the variation in muscle to bone ratio. The best simple correlation with muscle to bone ratio was ALA/CL (r = ·59). Other measures significantly correlated with muscle to bone ratio included ALA (r = 0·55), MS (r = 0·50) and carcass weight (r = 0·49). Multiple regression analyses identified a three-variable subset comprised of ALA, carcass weight and CL which was related (P carcass measures useful for predicting muscle to bone ratio.

  11. [Muscle-related adverse effects of statins].

    Science.gov (United States)

    Pohjola-Sintonen, Sinikka; Julkunen, Heikki

    2014-01-01

    Adverse effects on muscles occur in approximately 5 to 10% of patients taking statins. Drug interactions, associated diseases, agedness, low body weight, high statin dose and hereditary factors increase the risk of adverse effects. In most cases the muscle effects are mild and disappear upon discontinuation of the medication. Rhabdomyolysis is a severe though rare complication that can possibly result in renal damage. A totally different muscle-related adverse effect, necrotizing myopathy, has recently been linked to the use of statins. Its characteristic feature is progression of the symptoms in spite of discontinuation of the statin.

  12. MR imaging findings in diabetic muscle infarction.

    Science.gov (United States)

    Bajaj, Gitanjali; Nicholas, Richard; Pandey, Tarun; Montgomery, Corey; Jambhekar, Kedar; Ram, Roopa

    2014-10-01

    Diabetic muscle infarction is a rare, often unrecognized complication seen in patients with poorly controlled Diabetes Mellitus. The diagnosis is often missed and leads to unnecessary invasive investigations and inappropriate treatment. The patients usually present with unilateral thigh pain and swelling. MRI typically demonstrates diffuse swelling and increased T2 signal intensity within the affected muscles. The condition is self-limiting and is treated conservatively with bed rest and analgesics. Recurrences have been reported in the same or contralateral limb. We report a case of diabetic muscle infarction with spontaneous resolution of symptoms and imaging abnormality with recurrence on the contralateral side.

  13. Sex hormones and skeletal muscle weakness

    DEFF Research Database (Denmark)

    Sipilä, Sarianna; Narici, Marco; Kjaer, Michael

    2013-01-01

    Human ageing is accompanied with deterioration in endocrine functions the most notable and well characterized of which being the decrease in the production of sex hormones. Current research literature suggests that low sex hormone concentration may be among the key mechanism for sarcopenia...... and muscle weakness. Within the European large scale MYOAGE project, the role of sex hormones, estrogens and testosterone, in causing the aging-related loss of muscle mass and function was further investigated. Hormone replacement therapy (HRT) in women is shown to diminish age-associated muscle loss, loss...

  14. Skeletal muscle metastasis from uterine leiomyosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, J.M.; Brennan, D.D.; Taylor, D.H.; Eustace, S.J. [Cappagh National Orthopaedic Hospital, Department of Radiology, Dublin (Ireland); Holloway, D.P.; O' Keane, J.C. [Cappagh National Orthopaedic Hospital, Department of Pathology, Dublin (Ireland); Hurson, B. [Cappagh National Orthopaedic Hospital, Department of Orthopaedics, Dublin (Ireland)

    2004-11-01

    A case of a 68-year-old woman who presented with a rapidly enlarging painful right thigh mass is presented. She had a known diagnosis of uterine leiomyosarcoma following a hysterectomy for dysfunctional uterine bleeding. She subsequently developed a single hepatic metastatic deposit that responded well to radiofrequency ablation. Whole-body MRI and MRA revealed a vascular mass in the sartorius muscle and a smaller adjacent mass in the gracilis muscle, proven to represent metastatic leiomyosarcoma of uterine origin. To our knowledge, metastatic uterine leiomyosarcoma to the skeletal muscle has not been described previously in the English medical literature. (orig.)

  15. Skeletal muscle metastasis from uterine leiomyosarcoma.

    Science.gov (United States)

    O'Brien, J M; Brennan, D D; Taylor, D H; Holloway, D P; Hurson, B; O'Keane, J C; Eustace, S J

    2004-11-01

    A case of a 68-year-old woman who presented with a rapidly enlarging painful right thigh mass is presented. She had a known diagnosis of uterine leiomyosarcoma following a hysterectomy for dysfunctional uterine bleeding. She subsequently developed a single hepatic metastatic deposit that responded well to radiofrequency ablation. Whole-body MRI and MRA revealed a vascular mass in the sartorius muscle and a smaller adjacent mass in the gracilis muscle, proven to represent metastatic leiomyosarcoma of uterine origin. To our knowledge, metastatic uterine leiomyosarcoma to the skeletal muscle has not been described previously in the English medical literature.

  16. Optimal Control of Isometric Muscle Dynamics

    Directory of Open Access Journals (Sweden)

    Robert Rockenfeller

    2015-03-01

    Full Text Available We use an indirect optimal control approach to calculate the optimal neural stimulation needed to obtain measured isometric muscle forces. The neural stimulation of the nerve system is hereby considered to be a control function (input of the system ’muscle’ that solely determines the muscle force (output. We use a well-established muscle model and experimental data of isometric contractions. The model consists of coupled activation and contraction dynamics described by ordinary differential equations. To validate our results, we perform a comparison with commercial optimal control software.

  17. Vasodilatory mechanisms in contracting skeletal muscle

    DEFF Research Database (Denmark)

    Clifford, Philip S.; Hellsten, Ylva

    2004-01-01

    Skeletal muscle blood flow is closely coupled to metabolic demand, and its regulation is believed to be mainly the result of the interplay of neural vasoconstrictor activity and locally derived vasoactive substances. Muscle blood flow is increased within the first second after a single contraction...... and stabilizes within 30 s during dynamic exercise under normal conditions. Vasodilator substances may be released from contracting skeletal muscle, vascular endothelium, or red blood cells. The importance of specific vasodilators is likely to vary over the time course of flow, from the initial rapid rise...

  18. Expression of interleukin-15 in human skeletal muscle effect of exercise and muscle fibre type composition

    DEFF Research Database (Denmark)

    Nielsen, Anders Rinnov; Mounier, Remi; Plomgaard, Peter

    2007-01-01

    of recovery without any changes in muscle IL-15 protein content or plasma IL-15 at any of the investigated time points. In conclusion, IL-15 mRNA level is enhanced in skeletal muscles dominated by type 2 fibres and resistance exercise induces increased muscular IL-15 mRNA levels. IL-15 mRNA levels in skeletal......The cytokine interleukin-15 (IL-15) has been demonstrated to have anabolic effects in cell culture systems. We tested the hypothesis that IL-15 is predominantly expressed by type 2 skeletal muscle fibres, and that resistance exercise regulates IL-15 expression in muscle. Triceps brachii, vastus...... lateralis quadriceps and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers (n = 14), because these muscles are characterized by having different fibre-type compositions. In addition, healthy, normally physically active male subjects (n = 8) not involved...

  19. Recycle of temporal muscle in combination with free muscle transfer in the treatment of facial paralysis.

    Science.gov (United States)

    Kurita, Masakazu; Takushima, Akihiko; Shiraishi, Tomohiro; Kinoshita, Mikio; Ozaki, Mine; Harii, Kiyonori

    2013-07-01

    We experienced three patients with long-standing unilateral complete facial paralysis who previously underwent temporalis muscle transfer to the cheek for smile reconstruction. All patients complained of insufficient and uncomfortable buccal motion synchronised with masticatory movements and incomplete eyelid closure with ptotic eyebrow. To attain a near-natural smile and reliable eyelid closure, temporalis muscle was displaced from the cheek to the eyelid, and a neurovascular free latissimus dorsi muscle was transferred for the replacement of cheek motion. As a result, cheek motion synchronised with the contralateral cheek upon smiling and sufficient eyelid closure were obtained in all cases. Smile reconstruction using the temporal muscle is an easy and a versatile way in general. However, spontaneous smile is not achieved and peculiar movement of the cheek while eating is conspicuous in some cases. Replacement with neurovascular free latissimus dorsi muscle and recycling previously used temporalis muscle for eyelid closure are considered to be valuable for such cases.

  20. Muscle Interstitial Cells: A Brief Field Guide to Non-satellite Cell Populations in Skeletal Muscle.

    Science.gov (United States)

    Tedesco, Francesco Saverio; Moyle, Louise A; Perdiguero, Eusebio

    2017-01-01

    Skeletal muscle regeneration is mainly enabled by a population of adult stem cells known as satellite cells. Satellite cells have been shown to be indispensable for adult skeletal muscle repair and regeneration. In the last two decades, other stem/progenitor cell populations resident in the skeletal muscle interstitium have been identified as "collaborators" of satellite cells during regeneration. They also appear to have a key role in replacing skeletal muscle with adipose, fibrous, or bone tissue in pathological conditions. Here, we review the role and known functions of these different interstitial skeletal muscle cell types and discuss their role in skeletal muscle tissue homeostasis, regeneration, and disease, including their therapeutic potential for cell transplantation protocols.

  1. Muscles within muscles: a tensiomyographic and histochemical analysis of the normal human vastus medialis longus and vastus medialis obliquus muscles.

    Science.gov (United States)

    Travnik, Ludvik; Djordjevič, Srdjan; Rozman, Sergej; Hribernik, Marija; Dahmane, Raja

    2013-06-01

    The aim of this study was to show the connection between structure (anatomical and histochemical) and function (muscle contraction properties) of vastus medialis obliquus (VMO) and vastus medialis longus (VML). The non-invasive tensiomyography (TMG) method was used to determine the contractile properties (contraction time; T(c)) of VML and VMO muscle, as a reflection of the ratio between the slow and fast fibers in two groups of nine young men. VML and VMO significantly (P knee, and to the VMO, which maintains the stable position of the patella in the femoral groove. Our results obtained by TMG provided additional evidence that muscle fibers within the segments of VM muscle were not homogenous with regard to their contractile properties, thereby confirming the histochemical results. T(c) can be attributed to the higher percentage of slow-twitch fibers - type 1. The statistically shorter T(c) (P ≤ 0.001) of VMO (22.8 ± 4.0 ms) compared with VML (26.7 ± 4.0 ms) in our study is consistent with previously found differences in histochemical, morphological and electrophysiological data. In conclusion, the results of this study provide evidence that the VML and VMO muscles are not only anatomically and histochemically different muscles, but also functionally different biological structures.

  2. Changes in muscle strength and morphology after muscle unloading in Special Forces missions

    DEFF Research Database (Denmark)

    Thorlund, J B; Jakobsen, O; Madsen, T

    2011-01-01

    ) and immediately after (post1) an 8-day simulated special support and reconnaissance (SSR) mission and after 3 h of active recovery (post2). Maximal muscle strength (MVC) and rate of force development (RFD) were measured along with maximal counter movement jump height (JH). Muscle biopsies were obtained from...... the vastus lateralis at pre and post1. Acute reductions were found in MVC (11%), JH (10%) and RFD (17-22%) after 8 days of muscle unloading (post1) (P...

  3. Muscle fibre types of the lumbrical, interossei, flexor, and extensor muscles moving the index finger.

    Science.gov (United States)

    Hwang, Kun; Huan, Fan; Kim, Dae Joong

    2013-09-01

    The aim of this study was to determine the fibre types of the muscles moving the index fingers in humans. Fifteen forearms of eight adult cadavers were used. The sampled muscles were the first lumbrical (LM), first volar interosseous (VI), first dorsal interosseus (DI), second flexor digitorum profundus (FDP), second flexor digitorum superficialis (FDS), and extensor digitorum (ED). Six micrometer thick sections were stained for fast muscle fibres. The procedure was performed by applying mouse monoclonal anti-skeletal myosin antibody (fast) and avidin-biotin peroxidase complex staining. Rectangular areas (0.38 mm × 0.38 mm) were photographed and the boundaries of the muscle areas were marked on the translucent film. The numbers and sizes of the muscle fibres in each part were evaluated by the image analyser program and calculated per unit area (1 mm(2)). The proportion of the fast fibres was significantly (p = 0.012) greater in the intrinsic muscles (55.7 ± 17.1%) than in the extrinsic muscles (45.9 ± 17.1%). Among the six muscles, the VI had a significantly higher portion (59.3%) of fast fibres than the FDS (40.6%) (p = 0.005) or the FDP (45.1%) (p = 0.023). The density of the non-fast fibres was significantly (p = 0.015) greater in the extrinsic muscles (539.2 ± 336.8/mm(2)) than in the intrinsic muscles (383.4 ± 230.4/mm2). Since the non-fast fibres represent less fatigable fibres, it is thought that the extrinsic muscles have higher durability against fatigue, and the intrinsic muscles, including the LM, should move faster than the FDS or FDP because the MP joint should be flexed before the IP joint to grip an object.

  4. Muscle carnosine loading by beta-alanine supplementation is more pronounced in trained vs. untrained muscles.

    Science.gov (United States)

    Bex, T; Chung, W; Baguet, A; Stegen, S; Stautemas, J; Achten, E; Derave, W

    2014-01-15

    Carnosine occurs in high concentrations in human skeletal muscle and assists working capacity during high-intensity exercise. Chronic beta-alanine (BA) supplementation has consistently been shown to augment muscle carnosine concentration, but the effect of training on the carnosine loading efficiency is poorly understood. The aim of the present study was to compare muscle carnosine loading between trained and untrained arm and leg muscles. In a first study (n = 17), reliability of carnosine quantification by proton magnetic resonance spectroscopy ((1)H-MRS) was evaluated in deltoid and triceps brachii muscles. In a second study, participants (n = 35; 10 nonathletes, 10 cyclists, 10 swimmers, and 5 kayakers) were supplemented with 6.4 g/day of slow-release BA for 23 days. Carnosine content was evaluated in soleus, gastrocnemius medialis, and deltoid muscles by (1)H-MRS. All the results are reported as arbitrary units. In the nonathletes, BA supplementation increased carnosine content by 47% in the arm and 33% in the leg muscles (not significant). In kayakers, the increase was more pronounced in arm (deltoid) vs. leg (soleus + gastrocnemius) muscles (0.089 vs. 0.049), whereas the reverse pattern was observed in cyclists (0.065 vs. 0.084). Swimmers had significantly higher increase in carnosine in both deltoid (0.107 vs. 0.065) and gastrocnemius muscle (0.082 vs. 0.051) compared with nonathletes. We showed that 1) carnosine content can be reliably measured by (1)H-MRS in deltoid muscle, 2) carnosine loading is equally effective in arm vs. leg muscles of nonathletes, and 3) carnosine loading is more pronounced in trained vs. untrained muscles.

  5. Muscle side population cells from dystrophic or injured muscle adopt a fibro-adipogenic fate.

    Directory of Open Access Journals (Sweden)

    Christopher M Penton

    Full Text Available Muscle side population (SP cells are rare multipotent stem cells that can participate in myogenesis and muscle regeneration upon transplantation. While they have been primarily studied for the development of cell-based therapies for Duchenne muscular dystrophy, little is known regarding their non-muscle lineage choices or whether the dystrophic muscle environment affects their ability to repair muscle. Unfortunately, the study of muscle SP cells has been challenged by their low abundance and the absence of specific SP cell markers. To address these issues, we developed culture conditions for the propagation and spontaneous multi-lineage differentiation of muscle SP cells. Using this approach, we show that SP cells from wild type muscle robustly differentiate into satellite cells and form myotubes without requiring co-culture with myogenic cells. Furthermore, this myogenic activity is associated with SP cells negative for immune (CD45 and vascular (CD31 markers but positive for Pax7, Sca1, and the mesenchymal progenitor marker PDGFRα. Additionally, our studies revealed that SP cells isolated from dystrophic or cardiotoxin-injured muscle fail to undergo myogenesis. Instead, these SP cells rapidly expand giving rise to fibroblast and adipocyte progenitors (FAPs and to their differentiated progeny, fibroblasts and adipocytes. Our findings indicate that muscle damage affects the lineage choices of muscle SP cells, promoting their differentiation along fibro-adipogenic lineages while inhibiting myogenesis. These results have implications for a possible role of muscle SP cells in fibrosis and fat deposition in muscular dystrophy. In addition, our studies provide a useful in vitro system to analyze SP cell biology in both normal and pathological conditions.

  6. Brain and muscle Arnt-like 1 promotes skeletal muscle regeneration through satellite cell expansion

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Somik [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Yin, Hongshan [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Department of Cardiovascular Medicine, Third Affiliated Hospital, Hebei Medical University, Shijiazhuang 050051, Hebei (China); Nam, Deokhwa [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Li, Yong [Department of Pediatric Surgery, Center for Stem Cell Research and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030 (United States); Ma, Ke, E-mail: kma@houstonmethodist.org [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States)

    2015-02-01

    Circadian clock is an evolutionarily conserved timing mechanism governing diverse biological processes and the skeletal muscle possesses intrinsic functional clocks. Interestingly, although the essential clock transcription activator, Brain and muscle Arnt-like 1 (Bmal1), participates in maintenance of muscle mass, little is known regarding its role in muscle growth and repair. In this report, we investigate the in vivo function of Bmal1 in skeletal muscle regeneration using two muscle injury models. Bmal1 is highly up-regulated by cardiotoxin injury, and its genetic ablation significantly impairs regeneration with markedly suppressed new myofiber formation and attenuated myogenic induction. A similarly defective regenerative response is observed in Bmal1-null mice as compared to wild-type controls upon freeze injury. Lack of satellite cell expansion accounts for the regeneration defect, as Bmal1{sup −/−} mice display significantly lower satellite cell number with nearly abolished induction of the satellite cell marker, Pax7. Furthermore, satellite cell-derived primary myoblasts devoid of Bmal1 display reduced growth and proliferation ex vivo. Collectively, our results demonstrate, for the first time, that Bmal1 is an integral component of the pro-myogenic response that is required for muscle repair. This mechanism may underlie its role in preserving adult muscle mass and could be targeted therapeutically to prevent muscle-wasting diseases. - Highlights: • Bmal1 is highly inducible by muscle injury and myogenic stimuli. • Genetic ablation of Bmal1 significantly impairs muscle regeneration. • Bmal1 promotes satellite cell expansion during muscle regeneration. • Bmal1-deficient primary myoblasts display attenuated growth and proliferation.

  7. Severe paraspinal muscle involvement in facioscapulohumeral muscular dystrophy

    DEFF Research Database (Denmark)

    Dahlqvist, Julia R; Vissing, Christoffer R; Thomsen, Carsten;

    2014-01-01

    OBJECTIVE: In this study, involvement of paraspinal muscles in 50 patients with facioscapulohumeral dystrophy (FSHD) was evaluated using MRI. METHODS: The Dixon MRI technique was used in this observational study to quantify muscle fat content of paraspinal and leg muscles. Muscle strength in the ...

  8. Research on the Dynamic Performance of Polyacrylonitrile Muscles

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The dynamic property of polyacrylonitrile (PAN) muscles was tested. The test results can help us to master PAN muscles' mechanical and chemical behaviors, which are indispensable for us to build dynamic model for the artificial muscle. Furthermore, here we provide an important experimental way to study gel muscles.

  9. Induction and modulation of referred muscle pain in humans

    DEFF Research Database (Denmark)

    Laursen, René Johannes

    Muscle pain is a major factor in many disorders such as injuries, degenerative diseases, and cancer. The mechanisms underlying muscle pain are not fully understood. A particular problem in muscle pain is the relationship between local and referred muscle pain. Experimental pain models are useful...

  10. [Mathematical anatomy: muscles according to Stensen].

    Science.gov (United States)

    Andrault, Raphaële

    2010-01-01

    In his Elementorum Myologiae Specimen, Steno geometrizes "the new fabric of muscles" and their movement of contraction, so as to refute the main contemporary hypothesis about the functioning of the muscles. This physiological refutation relies on an abstract representation of the muscular fibre as a parallelepiped of flesh transversally linked to the tendons. Those two features have been comprehensively studied. But the method used by Steno, as well as the way he has chosen to present his physiological results, have so far been neglected. Yet, Steno's work follows a true synthetic order, which he conceives as a tool to separate uncertain anatomical "elements" from the certain ones. We will show that the true understanding of this "more geometrico" order is the only way to avoid frequent misconceptions of the scientific aim pursued by Steno, which is neither to give a mathematical explanation of the functioning of the muscles, nor to reduce the muscles to some mathematical shapes.

  11. Zika Attacks Nerves, Muscles, Other Tissues

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_164010.html Zika Attacks Nerves, Muscles, Other Tissues Monkey study may ... 2017 (HealthDay News) -- Scientists have learned where the Zika virus attacks the body in monkeys. In their ...

  12. Carbohydrates, Muscle Glycogen, and Improved Performance.

    Science.gov (United States)

    Sherman, W. Mike

    1987-01-01

    One way to improve athletic performance without harming the athlete's health is diet manipulation. This article explores the relationship between muscular endurance and muscle glycogen and discusses a diet and training approach to competition. (Author/MT)

  13. Skeletal muscle as an immunogenic organ

    DEFF Research Database (Denmark)

    Nielsen, Søren; Pedersen, Bente Klarlund

    2008-01-01

    During the past few years, a possible link between skeletal muscle contractile activity and immune changes has been established. This concept is based on the finding that exercise provokes an increase in a number of cytokines. We have suggested that cytokines and other peptides that are produced......; expressed and released by muscle fibers and exert either paracrine or endocrine effects should be classified as 'myokines'. Human skeletal muscle has the capacity to express several myokines belonging to distinct different cytokine classes and contractile activity plays a role in regulating the expression...... of cytokines in skeletal muscle. In the present review, we focus on the myokines interleukin (IL)-6, IL-8 and IL-15 and their possible anti-inflammatory, immunoregulatory and metabolic roles....

  14. Advances and challenges in skeletal muscle angiogenesis

    DEFF Research Database (Denmark)

    Olfert, I Mark; Baum, Oliver; Hellsten, Ylva;

    2016-01-01

    during health, but poorly controlled in disease - resulting in either excessive capillary growth (pathological angiogenesis) or losses in capillarity (rarefaction). Given that skeletal muscle comprises nearly 40% of body mass in humans, skeletal muscle capillary density has a significant impact...... on metabolism, endocrine function, and locomotion, and is tightly regulated at many different levels. Skeletal muscle is also high adaptable, and thus one of the few organ systems which can be experimentally manipulated (e.g. by exercise) to study physiologic regulation of angiogenesis. This review will focus...... on 1) the methodological concerns that have arisen in determining skeletal muscle capillarity, and 2) highlight the concepts that are reshaping our understanding of the angio-adaptation process. We also summarize selected new findings (physical influences, molecular changes and ultrastructural...

  15. Masseter and medial pterygoid muscle hypertrophy.

    Science.gov (United States)

    Guruprasad, R; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-09-26

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination are important in differentiating this benign condition from parotid or dental pathology, they cannot necessarily exclude rare malignant lesion within the muscle. Advanced imaging modalities like CT and MRI are essential to confirm the diagnosis. Here the authors are reporting a unique case of masseter muscle hypertrophy along with medial pterygoid hypertrophy which was missed clinically but confirmed using CT and MRI.

  16. YAP-mediated mechanotransduction in skeletal muscle

    Directory of Open Access Journals (Sweden)

    Martina eFischer

    2016-02-01

    Full Text Available Skeletal muscle is not only translating chemical energy into mechanical work, it is also a highly adaptive and regenerative tissue whose architecture and functionality is determined by its mechanical and physical environment. Processing intra- and extracellular mechanical signaling cues contributes to the regulation of cell growth, survival, migration and differentiation. Yes-associated Protein (YAP, a transcriptional coactivator downstream of the Hippo pathway and its paralogue, the transcriptional co-activator with PDZ-binding motif (TAZ, were recently found to play a key role in mechanotransduction in various tissues including skeletal muscle. Furthermore, YAP/TAZ modulate myogenesis and muscle regeneration and abnormal YAP activity has been reported in muscular dystrophy and rhabdomyosarcoma. Here, we summarize the current knowledge of mechanosensing and -signaling in striated muscle. We highlight the role of YAP signaling and discuss the different routes and hypotheses of its regulation in the context of mechanotransduction.

  17. The benefits of coffee on skeletal muscle.

    Science.gov (United States)

    Dirks-Naylor, Amie J

    2015-12-15

    Coffee is consumed worldwide with greater than a billion cups of coffee ingested every day. Epidemiological studies have revealed an association of coffee consumption with reduced incidence of a variety of chronic diseases as well as all-cause mortality. Current research has primarily focused on the effects of coffee or its components on various organ systems such as the cardiovascular system, with relatively little attention on skeletal muscle. Summary of current literature suggests that coffee has beneficial effects on skeletal muscle. Coffee has been shown to induce autophagy, improve insulin sensitivity, stimulate glucose uptake, slow the progression of sarcopenia, and promote the regeneration of injured muscle. Much more research is needed to reveal the full scope of benefits that coffee consumption may exert on skeletal muscle structure and function.

  18. Stronger Muscles May Pump Up Your Memory

    Science.gov (United States)

    ... 161647.html Stronger Muscles May Pump Up Your Memory Seniors saw lasting changes from weight-lifting twice ... may boost brain function in people with mild memory and thinking problems, a new study finds. The ...

  19. Medicines to Treat Muscle Spasms and Pain

    Science.gov (United States)

    ... Reports recommends methocarbamoI or chlorzoxazone . For muscle spasticity :  Baclofen If baclofen does not work well for you, then Consumer Reports recommends tizanidine . Cyclobenzaprine and baclofen are both prescription medicines. Cyclobenzaprine costs $8 to $ ...

  20. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    2016-01-01

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies......, which aimed to investigate: 1) The development of a clinical method to evaluate and distinguish neural (reflex mediated stiffness) and non-neural (passive muscle stiffness) components of muscle stiffness in adults with CP by objective and reliable measurements 2) The association between increased......, and good correlation to measurements from a stationary dynamometer. The second part of the thesis discusses the finding of a significant correlation between gait function, reduced rate of force development (RFD), and increased passive muscle stiffness in adults with CP. Previously, the reflex...

  1. Pathogenesis of Insulin Resistance in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Muhammad A. Abdul-Ghani

    2010-01-01

    Full Text Available Insulin resistance in skeletal muscle is manifested by decreased insulin-stimulated glucose uptake and results from impaired insulin signaling and multiple post-receptor intracellular defects including impaired glucose transport, glucose phosphorylation, and reduced glucose oxidation and glycogen synthesis. Insulin resistance is a core defect in type 2 diabetes, it is also associated with obesity and the metabolic syndrome. Dysregulation of fatty acid metabolism plays a pivotal role in the pathogenesis of insulin resistance in skeletal muscle. Recent studies have reported a mitochondrial defect in oxidative phosphorylation in skeletal muscle in variety of insulin resistant states. In this review, we summarize the cellular and molecular defects that contribute to the development of insulin resistance in skeletal muscle.

  2. Caring for muscle spasticity or spasms

    Science.gov (United States)

    ... patientinstructions/000063.htm Caring for muscle spasticity or spasms To use the sharing features on this page, ... strength-building exercises are helpful as are playing sports and doing daily tasks. Talk with your health ...

  3. Human Muscle Fatigue Model in Dynamic Motions

    CERN Document Server

    Ma, Ruina; Bennis, Fouad; Ma, Liang

    2012-01-01

    Human muscle fatigue is considered to be one of the main reasons for Musculoskeletal Disorder (MSD). Recent models have been introduced to define muscle fatigue for static postures. However, the main drawbacks of these models are that the dynamic effect of the human and the external load are not taken into account. In this paper, each human joint is assumed to be controlled by two muscle groups to generate motions such as push/pull. The joint torques are computed using Lagrange's formulation to evaluate the dynamic factors of the muscle fatigue model. An experiment is defined to validate this assumption and the result for one person confirms its feasibility. The evaluation of this model can predict the fatigue and MSD risk in industry production quickly.

  4. Acute Muscle Stretching and Shoulder Position Sense

    OpenAIRE

    Björklund, Martin; Djupsjöbacka, Mats; Crenshaw, Albert G.

    2006-01-01

    Context: Stretching is common among athletes as a potential method for injury prevention. Stretching-induced changes in the muscle spindle properties are a suggested mechanism, which may imply reduced proprioception after stretching; however, little is known of this association.

  5. Rupture of pectoralis major muscle: review article

    Directory of Open Access Journals (Sweden)

    Guity MR

    2010-05-01

    Full Text Available "nBackground: Rupture of pectoralis major muscle is a very rare and often athletic injury. These days in our country this injury occurs more frequently. This could be due to increase in professional participation of amateur people in different types of sport, like body building and weight-lifting (especially bench-pressing without adequate preparation, training and taking necessary precautions. In this article, we have tried to review several aspects of complex anatomy of pectoralis major muscle, epidemiology, mechanism, clinical presentations, imaging modalities, surgical indications and techniques of its rupture. Complex and especial anatomy of pectoralis major muscle, in its humeral insertion particularly, have a major role of its vulnerability to sudden and eccentric contraction as the main mechanism of rupture. Also, restoration of this complex anatomy seems to be important during surgical repair to have normal function of the muscle again.

  6. Skeletal muscle glucose uptake during exercise

    DEFF Research Database (Denmark)

    Rose, Adam John; Richter, Erik A.

    2005-01-01

    The increase in skeletal muscle glucose uptake during exercise results from a coordinated increase in rates of glucose delivery (higher capillary perfusion), surface membrane glucose transport, and intracellular substrate flux through glycolysis. The mechanism behind the movement of GLUT4...

  7. Aspects of skeletal muscle modelling.

    Science.gov (United States)

    Epstein, Marcelo; Herzog, Walter

    2003-09-29

    The modelling of skeletal muscle raises a number of philosophical questions, particularly in the realm of the relationship between different possible levels of representation and explanation. After a brief incursion into this area, a list of desiderata is proposed as a guiding principle for the construction of a viable model, including: comprehensiveness, soundness, experimental consistency, predictive ability and refinability. Each of these principles is illustrated by means of simple examples. The presence of internal constraints, such as incompressibility, may lead to counterintuitive results. A one-panel example is exploited to advocate the use of the principle of virtual work as the ideal tool to deal with these situations. The question of stability in the descending limb of the force-length relation is addressed and a purely mechanical analogue is suggested. New experimental results confirm the assumption that fibre stiffness is positive even in the descending limb. The indeterminacy of the force-sharing problem is traditionally resolved by optimizing a, presumably, physically meaningful target function. After presenting some new results in this area, based on a separation theorem, it is suggested that a more fundamental approach to the problem is the abandoning of optimization criteria in favour of an explicit implementation of activation criteria.

  8. Clofibrate, calcium and cardiac muscle.

    Science.gov (United States)

    Fairhurst, A S; Wickie, G; Peabody, T

    1982-03-01

    The anti-hyperlipidemic drug clofibrate produces negative inotropic effects and arrythmias in isolated perfused rabbit heart Langendorff preparations. In electrically stimulated rat left atria, clofibrate produces negative inotropic effects, the speed of onset and extent of which are decreased by raising the Ca concentration of the bathing medium. Sensitivity of isolated rat atria to clofibrate is not increased when the tissues are stimulated under slow Ca channel conditions, in which the tissues are activated by either isoproterenol or dibutyryl cyclic AMP, although sensitivity to clofibrate is decreased when atria are exposed to increasing concentrations of norepinephrine. Increasing the stimulation frequency of isolated guinea-pig atria to produce a positive treppe also decreases the inhibitory effect of clofibrate, while in rat atria the typical negative treppe is altered towards a positive treppe in presence of clofibrate. The effects of paired electrical stimulation are not diminished by the drug, suggesting that Ca release from the sarcoplasmic reticulum is not affected by clofibrate, although the drug inhibits the rate of Ca uptake by isolated cardiac sarcoplasmic reticulum and mitochondria. These results suggest that clofibrate has multiple effects on Ca functions in cardiac muscle.

  9. Sternocleidomastoid Muscle Flap after Parotidectomy.

    Science.gov (United States)

    Nofal, Ahmad Abdel-Fattah; Mohamed, Morsi

    2015-10-01

    Introduction Most patients after either superficial or total parotidectomy develop facial deformity and Frey syndrome, which leads to a significant degree of patient dissatisfaction. Objective Assess the functional outcome and esthetic results of the superiorly based sternocleidomastoid muscle (SCM) flap after superficial or total parotidectomy. Methods A prospective cohort study for 11 patients subjected to parotidectomy using a partial-thickness superiorly based SCM flap. The functional outcome (Frey syndrome, facial nerve involvement, and ear lobule sensation) and the esthetic results were evaluated subjectively and objectively. Results Facial nerve palsy occurred in 5 cases (45%), and all of them recovered completely within 6 months. The Minor starch iodine test was positive in 3 patients (27%), although only 1 (9%) subjectively complained of gustatory sweating. The designed visual analog score completed by the patients themselves ranged from 0 to 3 with a mean of 1.55 ± 0.93; the scores from the blinded evaluators ranged from 1 to 3 with a mean 1.64 ± 0.67. Conclusion The partial-thickness superiorly based SCM flap offers a reasonable cosmetic option for reconstruction following either superficial or total parotidectomy by improving the facial deformity. The flap also lowers the incidence of Frey syndrome objectively and subjectively with no reported hazard of the spinal accessory nerve.

  10. Sternocleidomastoid Muscle Flap after Parotidectomy

    Directory of Open Access Journals (Sweden)

    Nofal, Ahmad Abdel-Fattah

    2015-04-01

    Full Text Available Introduction Most patients after either superficial or total parotidectomy develop facial deformity and Frey syndrome, which leads to a significant degree of patient dissatisfaction. Objective Assess the functional outcome and esthetic results of the superiorly based sternocleidomastoid muscle (SCM flap after superficial or total parotidectomy. Methods A prospective cohort study for 11 patients subjected to parotidectomy using a partial-thickness superiorly based SCM flap. The functional outcome (Frey syndrome, facial nerve involvement, and ear lobule sensation and the esthetic results were evaluated subjectively and objectively. Results Facial nerve palsy occurred in 5 cases (45%, and all of them recovered completely within 6 months. The Minor starch iodine test was positive in 3 patients (27%, although only 1 (9% subjectively complained of gustatory sweating. The designed visual analog score completed by the patients themselves ranged from 0 to 3 with a mean of 1.55 ± 0.93; the scores from the blinded evaluators ranged from 1 to 3 with a mean 1.64 ± 0.67. Conclusion The partial-thickness superiorly based SCM flap offers a reasonable cosmetic option for reconstruction following either superficial or total parotidectomy by improving the facial deformity. The flap also lowers the incidence of Frey syndrome objectively and subjectively with no reported hazard of the spinal accessory nerve.

  11. Muscle-specific expression of hypoxia-inducible factor in human skeletal muscle

    DEFF Research Database (Denmark)

    Mounier, Rémi; Pedersen, Bente Klarlund; Plomgaard, Peter

    2010-01-01

    from triceps brachii (characterized by a high proportion of type II fibres), from soleus (characterized by a high proportion of type I fibres) and from vastus lateralis (characterized by an equal proportion of type I and II fibres). The hypothesis was that type I muscle fibres would have lower HIF-1...... a significantly higher VEGF protein content than vastus lateralis and triceps muscle. In conclusion, we have shown that there are muscle-specific differences in HIF-1alpha and VEGF expression within human skeletal muscle at rest in normoxic conditions. Recent results, when combined with the findings described...

  12. MUSCLE ACTIVATION DURING LOW-INTENSITY MUSCLE CONTRACTIONS WITH VARYING LEVELS OF EXTERNAL LIMB COMPRESSION

    Directory of Open Access Journals (Sweden)

    Tomohiro Yasuda

    2008-12-01

    Full Text Available The purpose was to investigate muscle activation during low- intensity muscle contractions with various levels of external limb compression to reduce muscle perfusion/outflow. A series of unilateral elbow flexion muscle contractions (30 repetitive contractions followed by 3 sets x 15 contractions was performed at 20% of 1RM with varying levels of external compression (0 (without compression, 98, 121, and 147 mmHg external compression around the upper arm. Electromyography (EMG signals were recorded from surface electrodes placed on the biceps brachii muscle and analyzed for integrated EMG (iEMG. Maximal voluntary isometric contraction (MVC decreased similarly during the control (0 mmHg and 98 mmHg external compression bout (~18%; the decline in MVC with 121 and 147 mmHg external compression was significantly greater (~37%. Muscle activation increased progressively throughout the contraction bout with each level of external compression, but iEMG was significantly greater during 147 mmHg external compression. In conclusion, low-intensity muscle contractions performed with external compression of 147 mmHg appears to alter muscle perfusion/outflow leading to increased muscle activation without decrements in work performed during the contraction bout

  13. Selective innervation of foreign muscles following damage or removal of normal muscle targets.

    Science.gov (United States)

    Boss, V; Wigston, D J

    1992-08-22

    The restoration of a normal pattern of neural connectivity following nerve injury depends upon the selective reinnervation of appropriate postsynaptic targets. Previous studies suggest that, in the neuromuscular system, recognition between regenerating motoneurons and target muscles depends upon the positions of origin of the motoneurons and muscles. In axolotls, portions of the motor pools of adjacent muscles overlap. We found that, following removal of a pair of adjacent hindlimb muscles, anterior and posterior iliotibialis, many regenerating iliotibialis motor axons invaded foreign muscles. A more anterior foreign muscle, puboischiofemoralis internus, received greater innervation from anterior iliotibialis motoneurons, whereas a more posterior muscle, iliofibularis, received greater innervation from posterior iliotibialis motoneurons. Furthermore, anterior iliotibialis motoneurons that reinnervated puboischiofemoralis internus occupied the rostral portion of anterior iliotibialis motor pool, which overlaps that of puboischiofemoralis internus. Anterior iliotibialis motoneurons that reinnervated iliofibularis occupied the caudal portion of the anterior iliotibialis motor pool, which overlaps that of iliofibularis. When both anterior and posterior iliotibialis were damaged so that their myofibers were permanently destroyed, the rostrocaudal origins of the motoneurons that reinnervated them were virtually the same, suggesting that the motoneurons had difficulty distinguishing between the myofiberless iliotibialis muscles. However, some iliotibialis motoneurons invaded puboischiofemoralis internus instead of their myofiberless targets. Puboischiofemoralis internus received more innervation from the anterior iliotibialis motoneurons than the positionally less appropriate posterior iliotibialis motoneurons. These data are consistent with the hypothesis that selective reinnervation of muscle depends upon a system of recognition cues based on position.

  14. Association between Thigh Muscle Volume and Leg Muscle Power in Older Women.

    Directory of Open Access Journals (Sweden)

    Ulrich Lindemann

    Full Text Available The construct of sarcopenia is still discussed with regard to best appropriate measures of muscle volume and muscle function. The aim of this post-hoc analysis of a cross-sectional experimental study was to investigate and describe the hierarchy of the association between thigh muscle volume and measurements of functional performance in older women. Thigh muscle volume of 68 independently living older women (mean age 77.6 years was measured via magnetic resonance imaging. Isometric strength was assessed for leg extension in a movement laboratory in sitting position with the knee flexed at 90° and for hand grip. Maximum and habitual gait speed was measured on an electronic walk way. Leg muscle power was measured during single leg push and during sit-to-stand performance. Thigh muscle volume was associated with sit-to-stand performance power (r = 0.628, leg push power (r = 0.550, isometric quadriceps strength (r = 0.442, hand grip strength (r = 0.367, fast gait speed (r = 0.291, habitual gait speed (r = 0.256, body mass index (r = 0.411 and age (r = -0.392. Muscle power showed the highest association with thigh muscle volume in healthy older women. Sit-to-stand performance power showed an even higher association with thigh muscle volume compared to single leg push power.

  15. Mechanical tension and spontaneous muscle twitching precede the formation of cross-striated muscle in vivo.

    Science.gov (United States)

    Weitkunat, Manuela; Lindauer, Martina; Bausch, Andreas; Schnorrer, Frank

    2017-02-07

    Muscle forces are produced by repetitive stereotyped acto-myosin units called sarcomeres. Sarcomeres are chained into linear myofibrils spanning the entire muscle fiber. In mammalian body muscles, myofibrils are aligned laterally resulting in their typical cross-striated morphology. Despite this detailed textbook knowledge about the adult muscle structure, it is still unclear how cross-striated myofibrils are built in vivo Here, we investigate the morphogenesis of Drosophila abdominal muscles and establish them as in vivo model for cross-striated muscle development. Using live imaging, we find that long immature myofibrils lacking a periodic acto-myosin pattern are built simultaneously in the entire muscle fiber and then align laterally to mature cross-striated myofibrils. Interestingly, laser micro-lesion experiments demonstrate that mechanical tension precedes the formation of the immature myofibrils. Moreover, these immature myofibrils do generate spontaneous Ca(2+) dependent contractions in vivo, which when chemically blocked result in cross-striation defects. Together, these results suggest a myofibrillogenesis model, in which mechanical tension and spontaneous muscle twitchings synchronise the simultaneous self-organisation of different sarcomeric protein complexes to build highly regular cross-striated myofibrils spanning throughout large muscle fibers.

  16. Muscle fiber types composition and type identified endplate morphology of forepaw intrinsic muscles in the rat.

    Science.gov (United States)

    Pan, Feng; Mi, Jing-Yi; Zhang, Yan; Pan, Xiao-Yun; Rui, Yong-Jun

    2016-06-01

    The failure to accept reinnervation is considered to be one of the reasons for the poor motor functional recovery of intrinsic hand muscles (IHMs) after nerve injury. Rat could be a suitable model to be used in simulating motor function recovery of the IHMs after nerve injury as to the similarities in function and anatomy of the muscles between human and rat. However, few studies have reported the muscle fiber types composition and endplate morphologic characteristics of intrinsic forepaw muscles (IFMs) in the rat. In this study, the myosin heavy chain isoforms and acetylcholine receptors were stained by immunofluorescence to show the muscle fiber types composition and endplates on type-identified fibers of the lumbrical muscles (LMs), interosseus muscles (IMs), abductor digiti minimi (AM) and flexor pollicis brevis (FM) in rat forepaw. The majority of IFMs fibers were labeled positively for fast-switch fiber. However, the IMs were composed of only slow-switch fiber. With the exception of the IMs, the other IFMs had a part of hybrid fibers. Two-dimensional morphological characteristics of endplates on I and IIa muscle fiber had no significant differences among the IFMs. The LMs is the most suitable IFMs of rat to stimulate reinnervation of the IHMs after nerve injury. Gaining greater insight into the muscle fiber types composition and endplate morphology in the IFMs of rat may help understand the pathological and functional changes of IFMs in rat model stimulating reinnervation of IHMs after peripheral nerve injury.

  17. Relative activity of respiratory muscles during prescribed inspiratory muscle training in healthy people.

    Science.gov (United States)

    Jung, Ju-Hyeon; Kim, Nan-Soo

    2016-03-01

    [Purpose] This study aimed to determine the effects of different intensities of inspiratory muscle training on the relative respiratory muscle activity in healthy adults. [Subjects and Methods] Thirteen healthy male volunteers were instructed to perform inspiratory muscle training (0%, 40%, 60%, and 80% maximal inspiratory pressure) on the basis of their individual intensities. The inspiratory muscle training was performed in random order of intensities. Surface electromyography data were collected from the right-side diaphragm, external intercostal, and sternocleidomastoid, and pulmonary functions (forced expiratory volume in 1 s, forced vital capacity, and their ratio; peak expiratory flow; and maximal inspiratory pressure) were measured. [Results] Comparison of the relative activity of the diaphragm showed significant differences between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. Furthermore, significant differences were found in sternocleidomastoid relative activity between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. [Conclusion] During inspiratory muscle training in the clinic, the patients were assisted (verbally or through feedback) by therapists to avoid overactivation of their accessory muscles (sternocleidomastoid). This study recommends that inspiratory muscle training be performed at an accurate and appropriate intensity through the practice of proper deep breathing.

  18. Morphological analysis and muscle-associated gene expression during different muscle growth phases of Megalobrama amblycephala.

    Science.gov (United States)

    Zhu, K C; Yu, D H; Zhao, J K; Wang, W M; Wang, H L

    2015-01-01

    Skeletal muscle growth is regulated by both positive and negative factors, such as myogenic regulatory factors (MRFs) and myostatin (MSTN), and involves both hyperplasia and hypertrophy. In the present study, morphological changes during muscle development in Megalobrama amblycephala were characterized and gene expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) analysis in juvenile [60, 90, 120, and 180 days post-hatching (dph)] and adult fish. Our results show that during muscle development, the frequency of muscle fibers with a diameter muscles, with a concomitant increase in the frequency of >30 μm fibers in red muscle and >50 μm fibers in white muscle. At 90-120 dph, the ratio of hyperplastic to hypertrophic areas in red and white muscles increased, but later decreased at 120-180 dph. The effect of hypertrophy was significantly larger than hyperplasia during these phases. qRT-PCR indicated MRF and MSTN (MSTNa and MSTNb) genes had similar expression patterns that peaked at 120 dph, with the exception of MSTNa. This new information on the molecular regulation of muscle growth and rapid growth phases will be of value to the cultivation of M. amblycephala.

  19. Effects of inspiratory muscle training on balance ability and abdominal muscle thickness in chronic stroke patients.

    Science.gov (United States)

    Oh, Dongha; Kim, Gayeong; Lee, Wanhee; Shin, Mary Myong Sook

    2016-01-01

    [Purpose] This study evaluated the effects of inspiratory muscle training on pulmonary function, deep abdominal muscle thickness, and balance ability in stroke patients. [Subjects] Twenty-three stroke patients were randomly allocated to an experimental (n = 11) or control group (n = 12). [Methods] The experimental group received inspiratory muscle training-based abdominal muscle strengthening with conventional physical therapy; the control group received standard abdominal muscle strengthening with conventional physical therapy. Treatment was conducted 20 minutes per day, 3 times per week for 6 weeks. Pulmonary function testing was performed using an electronic spirometer. Deep abdominal muscle thickness was measured by ultrasonography. Balance was measured using the Berg balance scale. [Results] Forced vital capacity, forced expiratory volume in 1 second, deep abdominal muscle thickness, and Berg balance scale scores were significantly improved in the experimental group than in the control group. [Conclusion] Abdominal muscle strengthening accompanied by inspiratory muscle training is recommended to improve pulmonary function in stroke patients, and may also be used as a practical adjunct to conventional physical therapy.

  20. Myoglobin plasma level related to muscle mass and fiber composition: a clinical marker of muscle wasting?

    Science.gov (United States)

    Weber, Marc-André; Kinscherf, Ralf; Krakowski-Roosen, Holger; Aulmann, Michael; Renk, Hanna; Künkele, Annette; Edler, Lutz; Kauczor, Hans-Ulrich; Hildebrandt, Wulf

    2007-08-01

    Progressive muscle wasting is a central feature of cancer-related cachexia and has been recognized as a determinant of poor prognosis and quality of life. However, until now, no easily assessable clinical marker exists that allows to predict or to track muscle wasting. The present study evaluated the potential of myoglobin (MG) plasma levels to indicate wasting of large locomotor muscles and, moreover, to reflect the loss of MG-rich fiber types, which are most relevant for daily performance. In 17 cancer-cachectic patients (weight loss 22%) and 27 age- and gender-matched healthy controls, we determined plasma levels of MG and creatine kinase (CK), maximal quadriceps muscle cross-sectional area (CSA) by magnetic resonance imaging, muscle morphology and fiber composition in biopsies from the vastus lateralis muscle, body cell mass (BCM) by impedance technique as well as maximal oxygen uptake (VO(2)max). In cachectic patients, plasma MG, muscle CSA, BCM, and VO(2)max were 30-35% below control levels. MG showed a significant positive correlation to total muscle CSA (r = 0.65, p max as an important functional readout. CK plasma levels appear to be less reliable because prolonged increases are observed in even subclinical myopathies or after exercise. Notably, cancer-related muscle wasting was not associated with increases in plasma MG or CK in this study.

  1. Ouabain exacerbates botulinum neurotoxin-induced muscle paralysis via progression of muscle atrophy in mice.

    Science.gov (United States)

    Fujikawa, Ryu; Muroi, Yoshikage; Unno, Toshihiro; Ishii, Toshiaki

    2010-12-01

    Botulinum neurotoxin serotype A (BoNT/A) inhibits acetylcholine release at the neuromuscular junction in isolated muscles, and ouabain can partially block its effect. However, it is not clear whether ouabain attenuates BoNT/A-induced neuromuscular paralysis in vivo. In this work, we investigated the effects of ouabain on BoNT/A-induced neuromuscular paralysis in mice. Ouabain was administered to mice intraperitoneally immediately after a single injection of BoNT/A into skeletal muscle. The effects of ouabain on BoNT/A-induced muscle paralysis were assessed by quantitative monitoring of muscle tension and digit abduction via the digit abduction scoring (DAS) assay. A single administration of ouabain significantly prolonged BoNT/A-induced neuromuscular paralysis. Moreover, consecutive daily injection of ouabain exacerbated BoNT/A-induced neuromuscular paralysis, and led to a significant decrease in both twitch and tetanic forces as assayed in isolated BoNT/A-injected muscles. We next looked at the effects of ouabain on BoNT/A-induced muscle atrophy. Administration of ouabain led to a decrease in the myofibrillar cross-sectional area (CSAs) by 14 post-BoNT/A injection. In addition, repeated administration of ouabain increased mRNA expression levels of ubiquitin ligases, which are markers of muscle atrophy, in BoNT/A-injected muscle. These results suggest that ouabain exacerbates BoNT/A-induced neuromuscular paralysis via a marked progression of BoNT/A-induced muscle atrophy.

  2. A Relationship Between the EMG Silent Period and Muscle Fatigue of the Masticatory Muscle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T. H.; Cho, I. J.; Kim, S. H. [The University of Seoul, Seoul (Korea); Yang, D. J. [Samsung Electronics Co., Ltd., Seoul (Korea); Lee, J. [Samchok National University, Samchok (Korea)

    2001-05-01

    Silent period(SP) is transient stops of muscle activity that are induced by mechanical or electrical stimulus and the duration of silent period is a important parameter that have been associated with symptoms of masticatory dysfunction. Muscle fatigue is induced by sustained muscular contractions. It is associated with the external manifestations as the inability to maintain a desired force output, muscular tremor, and localized pain. Muscle fatigue is a parameter that have been measured or monitored the deterioration of a performance of muscles. On the study of relationship between SP and masticatory muscle fatigue, Nagasawa suggested that SP increase up to 3 min. from the beginning of clenching when the subjects performed sustained contractions at 50% maximum clenching level. In this paper, in order to evaluate a relationship between SP and muscle fatigue, 10 SPs per 1 minute are measured at 10%, 30%, 50% maximum clenching level. We used the median frequency in order to quantify the degree of muscle fatigue. However, the results shows that the duration of silent period was not significantly affected by differing levels of muscle fatigue. Therefore, we suggest that the SP is not increased or decreased as the results of muscle fatigue, also the origin of the SP generation mechanism is discussed. (author). 18 refs., 10 figs., 1 tab.

  3. Effect of VEGF on the Regenerative Capacity of Muscle Stem Cells in Dystrophic Skeletal Muscle

    Science.gov (United States)

    Deasy, Bridget M; Feduska, Joseph M; Payne, Thomas R; Li, Yong; Ambrosio, Fabrisia; Huard, Johnny

    2009-01-01

    We have isolated a population of muscle-derived stem cells (MDSCs) that, when compared with myoblasts, display an improved regeneration capacity, exhibit better cell survival, and improve myogenesis and angiogenesis. In addition, we and others have observed that the origin of the MDSCs may reside within the blood vessel walls (endothelial cells and pericytes). Here, we investigated the role of vascular endothelial growth factor (VEGF)–mediated angiogenesis in MDSC transplantation–based skeletal muscle regeneration in mdx mice (an animal model of muscular dystrophy). We studied MDSC and MDSC transduced to overexpress VEGF; no differences were observed in vitro in terms of phenotype or myogenic differentiation. However, after in vivo transplantation, we observe an increase in angiogenesis and endogenous muscle regeneration as well as a reduction in muscle fibrosis in muscles transplanted with VEGF-expressing cells when compared to control cells. In contrast, we observe a significant decrease in vascularization and an increase in fibrosis in the muscles transplanted with MDSCs expressing soluble forms-like tyrosine kinase 1 (sFlt1) (VEGF-specific antagonist) when compared to control MDSCs. Our results indicate that VEGF-expressing cells do not increase the number of dystrophin-positive fibers in the injected mdx muscle, when compared to the control MDSCs. Together the results suggest that the transplantation of VEGF-expressing MDSCs improved skeletal muscle repair through modulation of angiogenesis, regeneration and fibrosis in the injected mdx skeletal muscle. PMID:19603004

  4. Fiber architecture of canine abdominal muscles.

    Science.gov (United States)

    Boriek, Aladin M; Ortize, Jaime; Zhu, Deshen

    2002-02-01

    During respiration, abdominal muscles experience loads, not only in the muscle-fiber direction but also transverse to the fibers. We wondered whether the abdominal muscles exhibit a fiber architecture that is similar to the diaphragm muscle, and, therefore, we chose two adjacent muscles: the internal oblique (IO), with about the same muscle length as the diaphragm, and the transverse abdominis (TA), which is twice as long as the diaphragm. First, we used acetylcholinesterase staining to examine the distribution of neuromuscular junctions on both surfaces of the TA and IO muscles in six dogs. A maximum of four irregular bands of neuromuscular junctions crossed the IO, and as many as six bands crossed the TA, which is consistent with a discontinuous fiber architecture. In six additional dogs, we examined fiber architecture of these muscles by microdissecting 103 fascicles from the IO and 139 from the TA. Each fascicle contained between 20 and 30 muscle fibers. The mean length of nonspanning fibers (NSF) ranged from 2.8 +/- 0.3 cm in the IO to 4.3 +/- 0.5 cm in the TA, and the mean length of spanning fibers ranged from 4.3 +/- 0.5 cm in the IO to 7.6 +/- 1.4 cm in the TA. NSF accounted for 89.6 +/- 1.5% of all fibers dissected from the IO and 99.1 +/- 0.2% of all fibers dissected from the TA. The percentage of NSF with both ends tapered was 6.2 +/- 1.0 and 41.0 +/- 2.3% for IO and TA, respectively. These data show that fiber architecture in either IO or TA is discontinuous, with much more short-tapered fibers in the TA than in the IO. When abdominal muscles are submaximally activated, as during both normal expiration and maximal expiratory efforts, muscle force could be transmitted to the cell membrane and to the extracellular intramuscular connective tissue by shear linkage, presumably via structural transmembrane proteins.

  5. Muscle pain: animal and human experimental and clinical studies.

    Science.gov (United States)

    Marchettini, P

    1993-10-01

    The search for the identification of the sensory apparatus encoding muscle pain sensation in humans is recounted. Basic neurophysiologic animal studies, leading to a description of slowly conducting afferent from muscle and definition of high threshold polymodal muscle nociceptors, and pioneer psychophysic human studies together with recent microneurographic experiments in humans are described. The phenomena of muscle pain broad localization and distant referral are discussed, and clinical implications are extrapolated to interpret muscle pain as a localizing sign of mononeuropathy or radiculopathy. The identification of human muscle nociceptors has defined the scientific standard to test emerging clinical descriptions having muscle pain as a symptom.

  6. Position Control of Single Pneumatic Muscle Actuator

    Institute of Scientific and Technical Information of China (English)

    FAN Wei; PENG Guang-zheng; NING Ru-xin

    2005-01-01

    The PID, fuzzy, self-organized fuzzy and self-organized fuzzy-PID controllers are adopted in the position control of single pneumatic muscle actuator. Experiments show that the self-organized fuzzy-PID is obviously effective for the position control of single pneumatic muscle actuator, which can realize precision within 0.3 mm and withstand 18N variable load plus about 36N fixed load. It is relatively precise and robust.

  7. Heterogeneity of muscle activity during sedentary behavior.

    Science.gov (United States)

    Pesola, Arto J; Laukkanen, Arto; Tikkanen, Olli; Finni, Taija

    2016-11-01

    Replacing sitting by standing has been hypothesized to reduce the health risks of sitting, based on the assumption that muscles are passive during sitting and active during standing. Interventions have been more effective in overweight (OW) than in normal weight (NW) individuals, but subjects' muscle activities have not been quantified. This study compared quadriceps and hamstring muscle electromyographic (EMG) activity between 57 NW (body mass index (BMI) 22.5 ± 1.5 kg/m(2), female n = 36) and 27 OW (BMI 28.4 ± 2.9 kg/m(2), female n = 8) subjects during non-fatiguing standing (15 s, EMGstanding) and sitting (30 min). EMG amplitude was normalized to EMG measured during maximal isometric knee extension and flexion (% EMGMVC), and sitting muscle inactivity and bursts were determined using 4 thresholds (60% or 90% EMGstanding and 1% or 2% EMGMVC). Comparisons were adjusted for sex, age, knee extension strength, and the individual threshold. Standing EMG amplitude was 36% higher in OW (1.9% ± 1.5% EMGMVC) than in NW (1.4% ± 1.4% EMGMVC, P < 0.05) subjects. During sitting, muscles were inactive 89.8% ± 12.7% of the measurement time with 12.7 ± 14.2 bursts/min across all thresholds. On average, 6% more activity was recorded in NW than in OW individuals for 3 of the 4 thresholds (P < 0.05 for 60% or 90% EMGstanding and 1% EMGMVC). In conclusion, the OW group had higher muscle activity amplitude during standing but more muscle inactivity during sitting for 3/4 of the thresholds tested. Interventions should test whether the observed heterogeneity in muscle activity affects the potential to gain cardiometabolic benefits from replacing sitting with standing.

  8. Preservative solution for skeletal muscle biopsy samples

    Science.gov (United States)

    Kurt, Yasemin Gulcan; Kurt, Bulent; Ozcan, Omer; Topal, Turgut; Kilic, Abdullah; Muftuoglu, Tuba; Acikel, Cengizhan; Sener, Kenan; Sahiner, Fatih; Yigit, Nuri; Aydin, Ibrahim; Alay, Semih; Ekinci, Safak

    2015-01-01

    Context: Muscle biopsy samples must be frozen with liquid nitrogen immediately after excision and maintained at -80°C until analysis. Because of this requirement for tissue processing, patients with neuromuscular diseases often have to travel to centers with on-site muscle pathology laboratories for muscle biopsy sample excision to ensure that samples are properly preserved. Aim: Here, we developed a preservative solution and examined its protectiveness on striated muscle tissues for a minimum of the length of time that would be required to reach a specific muscle pathology laboratory. Materials and Methods: A preservative solution called Kurt-Ozcan (KO) solution was prepared. Eight healthy Sprague-Dawley rats were sacrificed; striated muscle tissue samples were collected and divided into six different groups. Muscle tissue samples were separated into groups for morphological, enzyme histochemical, molecular, and biochemical analysis. Statistical method used: Chi-square and Kruskal Wallis tests. Results: Samples kept in the KO and University of Wisconsin (UW) solutions exhibited very good morphological scores at 3, 6, and 18 hours, but artificial changes were observed at 24 hours. Similar findings were observed for the evaluated enzyme activities. There were no differences between the control group and the samples kept in the KO or UW solution at 3, 6, and 18 hours for morphological, enzyme histochemical, and biochemical features. The messenger ribonucleic acid (mRNA) of β-actin gene was protected up to 6 hours in the KO and UW solutions. Conclusion: The KO solution protects the morphological, enzyme histochemical, and biochemical features of striated muscle tissue of healthy rats for 18 hours and preserves the mRNA for 6 hours. PMID:26019417

  9. Preservative solution for skeletal muscle biopsy samples

    Directory of Open Access Journals (Sweden)

    Yasemin Gulcan Kurt

    2015-01-01

    Full Text Available Context : Muscle biopsy samples must be frozen with liquid nitrogen immediately after excision and maintained at -80 o C until analysis. Because of this requirement for tissue processing, patients with neuromuscular diseases often have to travel to centers with on-site muscle pathology laboratories for muscle biopsy sample excision to ensure that samples are properly preserved. Aim: Here, we developed a preservative solution and examined its protectiveness on striated muscle tissues for a minimum of the length of time that would be required to reach a specific muscle pathology laboratory. Materials and Methods: A preservative solution called Kurt-Ozcan (KO solution was prepared. Eight healthy Sprague-Dawley rats were sacrificed; striated muscle tissue samples were collected and divided into six different groups. Muscle tissue samples were separated into groups for morphological, enzyme histochemical, molecular, and biochemical analysis. Statistical method used: Chi-square and Kruskal Wallis tests. Results: Samples kept in the KO and University of Wisconsin (UW solutions exhibited very good morphological scores at 3, 6, and 18 hours, but artificial changes were observed at 24 hours. Similar findings were observed for the evaluated enzyme activities. There were no differences between the control group and the samples kept in the KO or UW solution at 3, 6, and 18 hours for morphological, enzyme histochemical, and biochemical features. The messenger ribonucleic acid (mRNA of β-actin gene was protected up to 6 hours in the KO and UW solutions. Conclusion: The KO solution protects the morphological, enzyme histochemical, and biochemical features of striated muscle tissue of healthy rats for 18 hours and preserves the mRNA for 6 hours.

  10. Heterotopic Ossification of the Quadratus Lumborum Muscle

    OpenAIRE

    Alport, Brie; Horne, David; Burbridge, Brent

    2014-01-01

    Heterotopic ossification is a benign process of mature laminar bone formation in the soft tissues. A synonymous term used to describe this pathology in muscle is myositis ossificans. The pathogenesis is unclear, but is likely multifactorial. The basic pathology is thought to be ectopic production of osseous tissue as part of a repair process in response to tissue injury. This report describes a case of heterotopic ossification of the quadratus lumborum muscle as an incidental finding. This ca...

  11. Muscle Giants: Molecular Scaffolds in Sarcomerogenesis

    OpenAIRE

    2009-01-01

    Myofibrillogenesis in striated muscles is a highly complex process that depends on the coordinated assembly and integration of a large number of contractile, cytoskeletal, and signaling proteins into regular arrays, the sarcomeres. It is also associated with the stereotypical assembly of the sarcoplasmic reticulum and the transverse tubules around each sarcomere. Three giant, muscle-specific proteins, titin (3–4 MDa), nebulin (600–800 kDa), and obscurin (~720–900 kDa), have been proposed to p...

  12. Robustness of muscle synergies during visuomotor adaptation

    Directory of Open Access Journals (Sweden)

    Reinhard eGentner

    2013-09-01

    Full Text Available During visuomotor adaptation a novel mapping between visual targets and motor commands is gradually acquired. How muscle activation patterns are affected by this process is an open question. We tested whether the structure of muscle synergies is preserved during adaptation to a visuomotor rotation. Eight subjects applied targeted isometric forces on a handle instrumented with a force transducer while electromyographic (EMG activity was recorded from 13 shoulder and elbow muscles. The recorded forces were mapped into horizontal displacements of a virtual sphere with simulated mass, elasticity, and damping. The task consisted of moving the sphere to a target at one of eight equally spaced directions. Subjects performed three baseline blocks of 32 trials, followed by six blocks with a 45° CW rotation applied to the planar force, and finally three wash-out blocks without the perturbation. The sphere position at 100 ms after movement onset revealed significant directional error at the beginning of the rotation, a gradual learning in subsequent blocks, and aftereffects at the beginning of the wash-out. The change in initial force direction was closely related to the change in directional tuning of the initial EMG activity of most muscles. Throughout the experiment muscle synergies extracted using a non-negative matrix factorization algorithm from the muscle patterns recorded during the baseline blocks could reconstruct the muscle patterns of all other blocks with an accuracy significantly higher than chance indicating structural robustness. In addition, the synergies extracted from individual blocks remained similar to the baseline synergies throughout the experiment. Thus synergy structure is robust during visuomotor adaptation suggesting that changes in muscle patterns are obtained by rotating the directional tuning of the synergy recruitment.

  13. Cryotherapy induces an increase in muscle stiffness.

    Science.gov (United States)

    Point, Maxime; Guilhem, Gaël; Hug, François; Nordez, Antoine; Frey, Alain; Lacourpaille, Lilian

    2017-03-06

    Although cold application (i.e., cryotherapy) may be useful to treat sports injuries and to prevent muscle damage, it is unclear whether it has adverse effects on muscle mechanical properties. This study aimed to determine the effect of air-pulsed cryotherapy on muscle stiffness estimated using ultrasound shear wave elastography. Myoelectrical activity, ankle passive torque, shear modulus (an index of stiffness) and muscle temperature of the gastrocnemius medialis were measured before, during an air-pulsed cryotherapy (-30°) treatment of 4 sets of 4 minutes with 1 min recovery in between, and during a 40-min post-cryotherapy period. Muscle temperature significantly decreased after the second set of treatment (10 min: 32.3 ± 2.5°C; P < 0.001), peaked at 29 min (27.9 ± 2.2°C; P < 0.001) and remained below baseline values at 60 minutes (29.5 ± 2.0°C; P < 0.001). Shear modulus increased by +11.5 ± 11.8% after the second set (10 min; P = 0.011), peaked at 30 min (+34.7 ± 42.6%; P < 0.001) and remained elevated until the end of the post-treatment period (+25.4 ± 17.1%; P < 0.001). These findings provide evidence that cryotherapy induces an increase in muscle stiffness. This acute change in muscle mechanical properties may lower the amount of stretch that the muscle tissue is able to sustain without subsequent injury. This should be considered when using cryotherapy in athletic practice. This article is protected by copyright. All rights reserved.

  14. [Myofascial pain syndrome--fascial muscle pain].

    Science.gov (United States)

    Partanen, Juhani; Ojala, Tuula; Arokoski, Jari P A

    2010-01-01

    Symptoms of myofascial pain syndrome, i.e. fascial muscle pain may occur in several areas of the body, particularly in the neck-shoulder region. The muscle pain symptom in the neck-shoulder region is commonly termed tension neck pain or nonspecific neck pain, but myofascial pain syndrome can also be distinguished into its own diagnosis. This review deals with the clinical picture of myofascial pain syndrome along with pathophysiological hypotheses and treatment options.

  15. Masseter and medial pterygoid muscle hypertrophy

    OpenAIRE

    R, Guruprasad; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-01-01

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination ar...

  16. Dengue: muscle biopsy findings in 15 patients

    OpenAIRE

    Malheiros,S. M. F.; A. S. B. Oliveira; Schmidt, B.; Camargo Lima, J. G. [UNIFESP; Gabbai, A A

    1993-01-01

    Dengue is known to produce a syndrome involving muscles, tendons and joints. The hallmark of this syndrome is severe myalgia but includes fever, cutaneous rash, and headache. The neuromuscular aspects of this infection are outlined only in isolated reports, and the muscle histopathological features during myalgia have not been described. In order to ascertain the actual neuromuscular involvement in dengue and better comprehend the histological nature of myalgia, we performed a clinical and ne...

  17. Craniomandibular disorders and masticatory muscle function.

    Science.gov (United States)

    Bakke, M; Möller, E

    1992-02-01

    The heading craniomandibular disorders covers a wide range of abnormal and pathologic conditions accompanied by orofacial pain and impaired mandibular function, the masticatory muscles and the temporomandibular joints being the structures most frequently involved. Prevalences of severe craniomandibular disorders accompanied by headache and facial pain urgently in need of treatment are 1-2% in children, about 5% in adolescents, and 5-15% in adults, with higher values in women than in men. With respect to physiology and ergonomics, masticatory muscles are comparable to other human skeletal muscles, e.g. of shoulder, neck and lower back. Therefore these muscles share pathogenesis, symptoms and signs of muscular disorders caused by prolonged, low-level static contractions or intermittent isometric contractions at higher levels. Since the same elements of performance in the masticatory muscles are influenced by occlusal factors, they link the development of muscular fatigue, discomfort and pain to the dental occlusion. Furthermore, changes of the occlusal surfaces, e.g. due to dental treatment, may influence the performance of the masticatory muscles, and consequently interfere with local muscular function.

  18. Skeletal muscle disorders of glycogenolysis and glycolysis.

    Science.gov (United States)

    Godfrey, Richard; Quinlivan, Ros

    2016-07-01

    Skeletal muscle disorders of glycogenolysis and glycolysis account for most of the conditions collectively termed glycogen storage diseases (GSDs). These disorders are rare (incidence 1 in 20,000-43,000 live births), and are caused by autosomal or X-linked recessive mutations that result in a specific enzyme deficiency, leading to the inability to utilize muscle glycogen as an energy substrate. McArdle disease (GSD V) is the most common of these disorders, and is caused by mutations in the gene encoding muscle glycogen phosphorylase. Symptoms of McArdle disease and most other related GSDs include exercise intolerance, muscle contracture, acute rhabdomyolysis, and risk of acute renal failure. Older patients may exhibit muscle wasting and weakness involving the paraspinal muscles and shoulder girdle. For patients with these conditions, engaging with exercise is likely to be beneficial. Diagnosis is frequently delayed owing to the rarity of the conditions and lack of access to appropriate investigations. A few randomized clinical trials have been conducted, some focusing on dietary modification, although the quality of the evidence is low and no specific recommendations can yet be made. The development of EUROMAC, an international registry for these disorders, should improve our knowledge of their natural histories and provide a platform for future clinical trials.

  19. Oxidative proteome alterations during skeletal muscle ageing

    Directory of Open Access Journals (Sweden)

    Sofia Lourenço dos Santos

    2015-08-01

    Full Text Available Sarcopenia corresponds to the degenerative loss of skeletal muscle mass, quality, and strength associated with ageing and leads to a progressive impairment of mobility and quality of life. However, the cellular and molecular mechanisms involved in this process are not completely understood. A hallmark of cellular and tissular ageing is the accumulation of oxidatively modified (carbonylated proteins, leading to a decreased quality of the cellular proteome that could directly impact on normal cellular functions. Although increased oxidative stress has been reported during skeletal muscle ageing, the oxidized protein targets, also referred as to the ‘oxi-proteome’ or ‘carbonylome’, have not been characterized yet. To better understand the mechanisms by which these damaged proteins build up and potentially affect muscle function, proteins targeted by these modifications have been identified in human rectus abdominis muscle obtained from young and old healthy donors using a bi-dimensional gel electrophoresis-based proteomic approach coupled with immunodetection of carbonylated proteins. Among evidenced protein spots, 17 were found as increased carbonylated in biopsies from old donors comparing to young counterparts. These proteins are involved in key cellular functions such as cellular morphology and transport, muscle contraction and energy metabolism. Importantly, impairment of these pathways has been described in skeletal muscle during ageing. Functional decline of these proteins due to irreversible oxidation may therefore impact directly on the above-mentioned pathways, hence contributing to the generation of the sarcopenic phenotype.

  20. Chemical modification of muscle protein in diabetes.

    Science.gov (United States)

    Alt, Nadja; Carson, James A; Alderson, Nathan L; Wang, Yuping; Nagai, Ryoji; Henle, Thomas; Thorpe, Suzanne R; Baynes, John W

    2004-05-15

    Levels of glycation (fructose-lysine, FL) and advanced glycoxidation and lipoxidation end-products (AGE/ALEs) were measured in total skeletal (gastrocnemius) muscle and myofibril protein and compared to levels of the same compounds in insoluble skin collagen of control and diabetic rats. Levels of FL in total muscle and myofibril protein were 3-5% the level of FL in skin collagen. The AGE/ALEs, N(epsilon)-(carboxymethyl)lysine (CML) and N(epsilon)-(carboxyethyl)lysine, were also significantly lower in total muscle and myofibril protein, approximately 25% of levels in skin collagen. The newly described sulfhydryl AGE/ALE, S-(carboxymethyl)cysteine (CMC), was also measured in muscle; levels of CMC were comparable to those of CML and increased similarly in response to diabetes. Although FL and AGE/ALEs increased in muscle protein in diabetes, the relative increase was less than that seen in skin collagen. These data indicate that muscle protein is partially protected against the increase in both glycation and AGE/ALE formation in diabetes.

  1. Highly extensible skeletal muscle in snakes.

    Science.gov (United States)

    Close, Matthew; Perni, Stefano; Franzini-Armstrong, Clara; Cundall, David

    2014-07-15

    Many snakes swallow large prey whole, and this process requires large displacements of the unfused tips of the mandibles and passive stretching of the soft tissues connecting them. Under these conditions, the intermandibular muscles are highly stretched but subsequently recover normal function. In the highly stretched condition we observed in snakes, sarcomere length (SL) increased 210% its resting value (SL0), and actin and myosin filaments no longer overlapped. Myofibrils fell out of register and triad alignment was disrupted. Following passive recovery, SLs returned to 82% SL0, creating a region of double-overlapping actin filaments. Recovery required recoil of intracellular titin filaments, elastic cytoskeletal components for realigning myofibrils, and muscle activation. Stretch of whole muscles exceeded that of sarcomeres as a result of extension of folded terminal tendon fibrils, stretching of extracellular elastin and independent slippage of muscle fibers. Snake intermandibular muscles thus provide a unique model of how basic components of vertebrate skeletal muscle can be modified to permit extreme extensibility.

  2. Wave biomechanics of the skeletal muscle

    Science.gov (United States)

    Rudenko, O. V.; Sarvazyan, A. P.

    2006-12-01

    Results of acoustic measurements in skeletal muscle are generalized. It is shown that assessment of the pathologies and functional condition of the muscular system is possible with the use of shear waves. The velocity of these waves in muscles is much smaller than the velocity of sound; therefore, a higher symmetry type is formed for them. In the presence of a preferential direction (along muscle fibers), it is characterized by only two rather than five (as in usual media with the same anisotropy) moduli of elasticity. A covariant form of the corresponding wave equation is presented. It is shown that dissipation properties of skeletal muscles can be controlled by contracting them isometrically. Pulsed loads (shocks) and vibrations are damped differently, depending on their frequency spectrum. Characteristic frequencies on the order of tens and hundreds of hertz are attenuated due to actin-myosin bridges association/dissociation dynamics in the contracted muscle. At higher (kilohertz) frequencies, when the muscle is tensed, viscosity of the tissue increases by a factor of several tens because of the increase in friction experienced by fibrillar structures as they move relative to the surrounding liquid; the tension of the fibers changes the hydrodynamic conditions of the flow around them. Finally, at higher frequencies, the attenuation is associated with the rheological properties of biological molecules, in particular, with their conformational dynamics in the wave field. Models that describe the controlled shock dissipation mechanisms are proposed. Corresponding solutions are found, including those that allow for nonlinear effects.

  3. Analysis of muscle fatigue in helicopter pilots.

    Science.gov (United States)

    Balasubramanian, Venkatesh; Dutt, Ashwani; Rai, Shobhit

    2011-11-01

    Helicopter pilots espouse ergonomically unfavourable postures and endure vibration which result in low back pain. The objective of this study was to investigate the effects of a helicopter flight on pilots back and shoulder muscles using surface Electromyography (sEMG) analysis. This study also correlates low back pain symptoms from Rehabilitation Bioengineering Group Pain Scale (RBGPS) questionnaire with muscle fatigue rates obtained. RBGPS was administered on 20 Coast Guard helicopter pilots. sEMG was acquired before and after flight from erector spinae and trapezius muscles in 8 of these 20 pilots. Statistical analysis of time and frequency domain parameters indicated significant fatigue in right trapezius muscle due to flying. Muscle fatigue correlated with average duration of flight (r² = 0.913), total service as pilot (r² = 0.825), pain (r² = 0.463) and total flying hours (r² = 0.507). However, muscle fatigue weakly correlated with Body Mass Index (BMI) (r² = 0.000144) and age (r² = 0.033).

  4. Dengue: muscle biopsy findings in 15 patients

    Directory of Open Access Journals (Sweden)

    S.M.F. Malheiros

    1993-06-01

    Full Text Available Dengue is known to produce a syndrome involving muscles, tendons and joints. The hallmark of this syndrome is severe myalgia but includes fever, cutaneous rash, and headache. The neuromuscular aspects of this infection are outlined only in isolated reports, and the muscle histopathological features during myalgia have not been described. In order to ascertain the actual neuromuscular involvement in dengue and better comprehend the histological nature of myalgia, we performed a clinical and neurological evaluation, a serum CPK level and a muscle biopsy (with histochemistry in 15 patients (4 males, median age 23 years (range 14-47 with classic dengue fever, serologically confirmed, during the bra-zilian dengue epidemics from September 1986 to March 1987. All patients had a history of fever, headache and severe myalgia. Upon examination 4 had a cutaneous rash, 3 had fever, and 3 a small hepatomegaly. The neurological examination was unremarkable in all and included a manual muscle test. CPK was mildly elevated in only 3 patients. Muscle biopsy revealed a light to moderate perivascular mononuclear infiltrate in 12 patients and lipid accumulation in 11. Mild mitochondrial proliferation was seen in 3, few central nuclei in 3, rare foci of myonecrosis in 3, and 2 patients had type grouping. Dengue in our patients, produced myalgia but no detectable muscle weakness or other neuromuscular involvement. The main histopathological correlation with myalgia seems to be a perivascular mononuclear infiltrate and lipid accumulation.

  5. An animal model for human masseter muscle: histochemical characterization of mouse, rat, rabbit, cat, dog, pig, and cow masseter muscle

    DEFF Research Database (Denmark)

    Tuxen, A; Kirkeby, S

    1990-01-01

    .4, type IM fibers react moderately, and type II fibers react strongly. Rat and mouse masseter muscles contained type II fibers only, as did some rabbit masseter muscles, whereas other rabbit masseter muscles possessed equal amounts of type I and II fibers. Cat and dog masseter muscles possessed both type...

  6. Assessment of isokinetic muscle function in Korea male volleyball athletes

    OpenAIRE

    Kim, Chang-Gyun; Jeoung, Bog Ja

    2016-01-01

    Volleyball players performed numerous repetitions of spike actions, which uses and requires strong and explosive force, and control of the muscles of the shoulder, lower back, and legs. Muscle imbalance is one of the main causes of sport injuries. The purpose of this study was to assess isokinetic muscle functions in male volleyball players. We thus aim to accurately evaluate their muscle functions, and identify the best training strategy to achieve optimal muscle strength balance in future t...

  7. Anatomic variation of the iliacus and psoas major muscles

    OpenAIRE

    Fabrizio PA

    2011-01-01

    Routine dissection has identified a previously unrecorded unilateral variation of the iliacus and psoas muscles in a 91-year-old female cadaver. A variant iliacus muscle belly originated from the superior lateral aspect of the iliac fossa and after traversing the iliac fossa in a nearly horizontal plane, inserted into the psoas major muscle forming a blended iliacus-psoas muscle. The femoral nerve coursed laterally behind the muscle variant to the superior edge of the blended iliacus-psoas. T...

  8. Car-Pi – Analys och guidning för bra bilkörning

    OpenAIRE

    Hasan, Ali; Araby Salem, Ahmed

    2013-01-01

    Syftet med detta examensarbete var att skapa ett serverprogram i en enkortsdator som arbetar i realtid för att kunna hjälpa människor att köra mer ekonomiskt och miljövänligt i deras vardag. Detta var ett av målen ställda av produktbeställaren Ziggy Creative Colony. Ett mer långsiktigt mål från beställaren är att datorn skall installeras i en bil och kopplas till bilens on-board diagnostic-II (OBD-II)-uttag. Datorn ska sedan, via OBD-II, kunna samla information som till exempel hastighet, acc...

  9. Muscle fiber viability, a novel method for the fast detection of ischemic muscle injury in rats.

    Science.gov (United States)

    Turóczi, Zsolt; Arányi, Péter; Lukáts, Ákos; Garbaisz, Dávid; Lotz, Gábor; Harsányi, László; Szijártó, Attila

    2014-01-01

    Acute lower extremity ischemia is a limb- and life-threatening clinical problem. Rapid detection of the degree of injury is crucial, however at present there are no exact diagnostic tests available to achieve this purpose. Our goal was to examine a novel technique - which has the potential to accurately assess the degree of ischemic muscle injury within a short period of time - in a clinically relevant rodent model. Male Wistar rats were exposed to 4, 6, 8 and 9 hours of bilateral lower limb ischemia induced by the occlusion of the infrarenal aorta. Additional animals underwent 8 and 9 hours of ischemia followed by 2 hours of reperfusion to examine the effects of revascularization. Muscle samples were collected from the left anterior tibial muscle for viability assessment. The degree of muscle damage (muscle fiber viability) was assessed by morphometric evaluation of NADH-tetrazolium reductase reaction on frozen sections. Right hind limbs were perfusion-fixed with paraformaldehyde and glutaraldehyde for light and electron microscopic examinations. Muscle fiber viability decreased progressively over the time of ischemia, with significant differences found between the consecutive times. High correlation was detected between the length of ischemia and the values of muscle fiber viability. After reperfusion, viability showed significant reduction in the 8-hour-ischemia and 2-hour-reperfusion group compared to the 8-hour-ischemia-only group, and decreased further after 9 hours of ischemia and 2 hours of reperfusion. Light- and electron microscopic findings correlated strongly with the values of muscle fiber viability: lesser viability values represented higher degree of ultrastructural injury while similar viability results corresponded to similar morphological injury. Muscle fiber viability was capable of accurately determining the degree of muscle injury in our rat model. Our method might therefore be useful in clinical settings in the diagnostics of acute ischemic

  10. Muscle activation patterns when passively stretching spastic lower limb muscles of children with cerebral palsy.

    Science.gov (United States)

    Bar-On, Lynn; Aertbeliën, Erwin; Molenaers, Guy; Desloovere, Kaat

    2014-01-01

    The definition of spasticity as a velocity-dependent activation of the tonic stretch reflex during a stretch to a passive muscle is the most widely accepted. However, other mechanisms are also thought to contribute to pathological muscle activity and, in patients post-stroke and spinal cord injury can result in different activation patterns. In the lower-limbs of children with spastic cerebral palsy (CP) these distinct activation patterns have not yet been thoroughly explored. The aim of the study was to apply an instrumented assessment to quantify different muscle activation patterns in four lower-limb muscles of children with CP. Fifty-four children with CP were included (males/females n = 35/19; 10.8 ± 3.8 yrs; bilateral/unilateral involvement n =  32/22; Gross Motor Functional Classification Score I-IV) of whom ten were retested to evaluate intra-rater reliability. With the subject relaxed, single-joint, sagittal-plane movements of the hip, knee, and ankle were performed to stretch the lower-limb muscles at three increasing velocities. Muscle activity and joint motion were synchronously recorded using inertial sensors and electromyography (EMG) from the adductors, medial hamstrings, rectus femoris, and gastrocnemius. Muscles were visually categorised into activation patterns using average, normalized root mean square EMG (RMS-EMG) compared across increasing position zones and velocities. Based on the visual categorisation, quantitative parameters were defined using stretch-reflex thresholds and normalized RMS-EMG. These parameters were compared between muscles with different activation patterns. All patterns were dominated by high velocity-dependent muscle activation, but in more than half, low velocity-dependent activation was also observed. Muscle activation patterns were found to be both muscle- and subject-specific (pmuscles into activation patterns (pmuscles with different patterns react differently to treatment.

  11. Trunk muscle activities during abdominal bracing: comparison among muscles and exercises.

    Science.gov (United States)

    Maeo, Sumiaki; Takahashi, Takumi; Takai, Yohei; Kanehisa, Hiroaki

    2013-01-01

    Abdominal bracing is often adopted in fitness and sports conditioning programs. However, there is little information on how muscular activities during the task differ among the muscle groups located in the trunk and from those during other trunk exercises. The present study aimed to quantify muscular activity levels during abdominal bracing with respect to muscle- and exercise-related differences. Ten healthy young adult men performed five static (abdominal bracing, abdominal hollowing, prone, side, and supine plank) and five dynamic (V- sits, curl-ups, sit-ups, and back extensions on the floor and on a bench) exercises. Surface electromyogram (EMG) activities of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spinae (ES) muscles were recorded in each of the exercises. The EMG data were normalized to those obtained during maximal voluntary contraction of each muscle (% EMGmax). The % EMGmax value during abdominal bracing was significantly higher in IO (60%) than in the other muscles (RA: 18%, EO: 27%, ES: 19%). The % EMGmax values for RA, EO, and ES were significantly lower in the abdominal bracing than in some of the other exercises such as V-sits and sit-ups for RA and EO and back extensions for ES muscle. However, the % EMGmax value for IO during the abdominal bracing was significantly higher than those in most of the other exercises including dynamic ones such as curl-ups and sit-ups. These results suggest that abdominal bracing is one of the most effective techniques for inducing a higher activation in deep abdominal muscles, such as IO muscle, even compared to dynamic exercises involving trunk flexion/extension movements. Key PointsTrunk muscle activities during abdominal bracing was examined with regard to muscle- and exercise-related differences.Abdominal bracing preferentially activates internal oblique muscles even compared to dynamic exercises involving trunk flexion/extension movements.Abdominal bracing should be

  12. Influence of different control strategies on muscle activation patterns in trunk muscles.

    Science.gov (United States)

    Hansen, Laura; Anders, Christoph

    2014-12-01

    Adequate training of the trunk muscles is essential to prevent low back pain. Although sit-ups are simple to perform, the perceived high effort is the reason why training the abdominal muscles is seldom continued over a longer period of time. It is well known that the abdominal muscles are inferior to the back muscles in terms of force, but this cannot explain the extreme difference in perceived effort between trunk flexion and extension tasks. Therefore, this study was aimed at the identification of control strategy influences on the muscular stress level. Thirty-nine subjects were investigated. The performed tasks were restricted to the sagittal plane and were implemented with simulated and realized tilt angles. Subjects were investigated in an upright position with their lower bodies fixed and their upper bodies free. Posture-controlled tasks involved graded forward and backward tilting, while force-controlled tasks involved the application of force based on a virtual tilt angle. The Surface EMG (SEMG) was taken from five trunk muscles on both sides. Control strategies seemed to have no systematic influence on the SEMG amplitudes of the back muscles. In contrast, the abdominal muscles exhibited significantly higher stress levels under posture-controlled conditions without relevantly increasing antagonistic co-activation of back muscles. The abdominal muscles' relative differences ranged from an average of 20% for the external oblique abdominal muscle to approximately 40% for the rectus abdominal muscle. The perceived high effort expended during sit-ups can now be explained by the posture-controlled contractions that are required.

  13. Artificial muscle using nonlinear elastomers

    Science.gov (United States)

    Ratna, Banahalli

    2002-03-01

    Anisotropic freestanding films or fibers of nematic elastomers from laterally attached side-chain polymers show muscle-like mechanical properties. The orientational order of the liquid crystal side groups imposes a conformational anisotropy in the polymer backbone. When a large change in the order parameter occurs, as at the nematic-isotropic phase transition, there is a concomitant loss of order in the backbone which results in a contraction of the film in the direction of the director orientation. The crosslinked network imposes a symmetry-breaking field on the nematic and drives the nematic-isotropic transition towards a critical point with the application of external stress. Isostrain studies on these nonlinear elastomers, show that there are large deviations from ideal classical rubber elasticity and the contributions from total internal energy to the elastic restoring force cannot be ignored. The liquid crystal elastomers exhibiting anisoptopic contraction/extension coupled with a graded strain response to an applied external stimulus provide an excellent framework for mimicking muscular action. Liquid crystal elastomers by their very chemical nature have a number of ‘handles’ such as the liquid crystalline phase range, density of crosslinking, flexibility of the backbone, coupling between the backbone and the mesogen and the coupling between the mesogen and the external stimulus, that can be tuned to optimize the mechanical properties. We have demonstrated actuation in nematic elastomers under thermal and optical stimuli. We have been able to dope the elastomers with dyes to make them optically active. We have also doped them with carbon nanotubes in order to increase the thermal and electrical conductivity of the elastomer.

  14. Age-related botulinum toxin effects on muscle fiber conduction velocity in non-injected muscles

    NARCIS (Netherlands)

    Lange, Fiete; van Weerden, Tiemen W.; van der Hoeven, Johannes H.

    2007-01-01

    Objective: We studied systemic effects of botulinum toxin (BTX) treatment on muscle fiber conduction velocity (MFCV) and possible effects of age. Methods: MFCV was determined by an invasive EMG method in the biceps brachii muscle. Seventeen BTX treated patients and 58 controls were investigated. BTX

  15. SUPERNORMAL MUSCLE-FIBER CONDUCTION-VELOCITY DURING INTERMITTENT ISOMETRIC-EXERCISE IN HUMAN MUSCLE

    NARCIS (Netherlands)

    VANDERHOEVEN, JH; LANGE, F

    1994-01-01

    Muscle fiber conduction velocity (MFCV) and surface electromyographic parameters were studied in the brachial biceps muscle of healthy males during voluntary intermittent isometric contractions at 50% of maximum force. Recovery in the following 15 min was then observed. The measurements were perform

  16. Deletion of muscle GRP94 impairs both muscle and body growth by inhibiting local IGF production.

    Science.gov (United States)

    Barton, Elisabeth R; Park, SooHyun; James, Jose K; Makarewich, Catherine A; Philippou, Anastassios; Eletto, Davide; Lei, Hanqin; Brisson, Becky; Ostrovsky, Olga; Li, Zihai; Argon, Yair

    2012-09-01

    Insulin-like growth factors (IGFs) are critical for development and growth of skeletal muscles, but because several tissues produce IGFs, it is not clear which source is necessary or sufficient for muscle growth. Because it is critical for production of both IGF-I and IGF-II, we ablated glucose-regulated protein 94 (GRP94) in murine striated muscle to test the necessity of local IGFs for normal muscle growth. These mice exhibited smaller skeletal muscles with diminished IGF contents but with normal contractile function and no apparent endoplasmic reticulum stress response. This result shows that muscles rely on GRP94 primarily to support local production of IGFs, a pool that is necessary for normal muscle growth. In addition, body weights were ∼30% smaller than those of littermate controls, and circulating IGF-I also decreased significantly, yet glucose homeostasis was maintained with little disruption to the growth hormone pathway. The growth defect was complemented on administration of recombinant IGF-I. Thus, unlike liver production of IGF-I, muscle IGF-I is necessary not only locally but also globally for whole-body growth.

  17. Histochemical and morphometric characteristics of muscle fibres: breeds and muscles comparison

    Directory of Open Access Journals (Sweden)

    G. Toscano Pagano

    2011-03-01

    Full Text Available Fibres histochemical characteristics seem affect the meat quality obtained from the skeletal muscles. In fact, the red fibres metabolise and store more lipid than the white ones (Ashmore et al., 1972, so important meat characteristics could be influenced by the muscle fibre type, as recently investigated (Morita et al., 2000; Ozawa et al., 2000; Vestergaard et al., 2000a, 2000b....

  18. Engineered muscle systems having individually addressable distributed muscle actuators controlled by optical stimuli.

    Science.gov (United States)

    Neal, Devin; Asada, H Harry

    2013-01-01

    A multi degree-of-freedom system using live skeletal muscles as actuators is presented. Millimeter-scale, optically excitable 3D skeletal muscle strips are created by culturing genetically coded precursory muscle cells that are activated with light: optogenetics. These muscle bio-actuators are networked together to create a distributed actuator system. Unlike traditional mechanical systems where fixed axis joints are rotated with electric motors, the new networked muscle bio-actuators can activate loads having no fixed joint. These types of loads include shoulders, the mouth, and the jaw. The optogenetic approach offers high spatiotemporal resolution for precise control of muscle activation, and opens up the possibility to activate hundreds of interconnected muscles in a spatiotemporally coordinated manner. In this work, we explore the design of robotic systems composed of multiple light-activated live muscular actuator units. We describe and compare massively parallel and highly serial/networked distributions of these building-block actuator units. We have built functional fundamental prototypes and present experimental results to demonstrate the feasibility of the construction of larger scale muscle systems.

  19. Muscle fibre types in the external eye muscles of the pigeon, Columba livia.

    Science.gov (United States)

    McVean, A; Stelling, J; Rowlerson, A

    1987-10-01

    Fibre typing with antisera raised against specific myosin types from muscles of known physiological properties were used to characterise the fibre types within the oculorotatory muscles of pigeons. Fibres reacting strongly to antiserum anti-ALD (specific for tonic fibre myosin) were found lying along the global margin of the muscle and also in a layer lying immediately beneath a discrete band of fibres running along the orbital margin. These fibres resembled those of the skeletal muscle ALD in their type properties. Using another antiserum, anti-I, specific for slow twitch and to a lesser extent, slow tonic myosins, it was possible to identify another slow fibre type which formed the orbital layer and also lay scattered randomly through the body of the muscle. No equivalent to this type was found in the skeletal muscles ALD or iliofibularis. The remaining fibres which did not react with either anti-ALD or anti-I formed 58% of the fibre population and reacted with an antiserum specific for fast myosin. However, their response to alkali preincubation suggests that the fast fibres of eye muscles also contain a myosin which is different from those in skeletal muscle.

  20. Smooth muscle actin and myosin expression in cultured airway smooth muscle cells.

    Science.gov (United States)

    Wong, J Z; Woodcock-Mitchell, J; Mitchell, J; Rippetoe, P; White, S; Absher, M; Baldor, L; Evans, J; McHugh, K M; Low, R B

    1998-05-01

    In this study, the expression of smooth muscle actin and myosin was examined in cultures of rat tracheal smooth muscle cells. Protein and mRNA analyses demonstrated that these cells express alpha- and gamma-smooth muscle actin and smooth muscle myosin and nonmuscle myosin-B heavy chains. The expression of the smooth muscle specific actin and myosin isoforms was regulated in the same direction when growth conditions were changed. Thus, at confluency in 1 or 10% serum-containing medium as well as for low-density cells (50-60% confluent) deprived of serum, the expression of the smooth muscle forms of actin and myosin was relatively high. Conversely, in rapidly proliferating cultures at low density in 10% serum, smooth muscle contractile protein expression was low. The expression of nonmuscle myosin-B mRNA and protein was more stable and was upregulated only to a small degree in growing cells. Our results provide new insight into the molecular basis of differentiation and contractile function in airway smooth muscle cells.