Supinator Strength Research Articles

Functional reconstruction of elbow flexion with latissimus dorsi muscle rotational transfer: two case reports

BackgroundWe report two cases of biceps brachii and brachialis paralysis due to musculocutaneous nerve injury in which elbow joint flexion was reconstructed using rotational transfer of the latissimus dorsi muscle with sutures to the radial and ulnar tuberosities, thereby enabling flexion by simultaneous activation of the humeroradial and humeroulnar joints. In cases of associated brachialis paralysis, weaker flexion strength can be expected when the forearm is in a pronated position than when it is in a supinated state. To the best of our knowledge, no previous study has reported the rotational position of the forearm during elbow joint flexion reconstruction.Case presentationCase 1 involved a 30-year-old Asian male who presented with a rupture of the musculocutaneous, median, radial, and ulnar nerves. Reconstruction was performed by rotational transfer of the latissimus dorsi muscle. In this case, the supination and pronation flexion forces were equal. Case 2 involved a 50-year-old Asian man who presented with partial loss of the musculocutaneous nerve, biceps brachii, and pectoralis major due to debridement. Reconstruction was performed by rotational transfer of the latissimus dorsi muscle. In this case, supination and pronation flexion strengths were demonstrated to be equal. Our reconstruction method used the rotational transfer of the latissimus dorsi muscle; the distal muscle flap was divided into radial and ulnar sides to allow elbow joint flexion by simultaneously activating the humeroradial and humeroulnar joints. These sides were then fixed to the anchors at the radial and ulnar tuberosities. Finally, they were wrapped around the myotendinous junction of the biceps brachii or brachialis and secured using sutures.ConclusionsAlthough larger studies are required to verify these methods, this case study successfully demonstrates the following: (1) the flexion strength in the supinated position was equal to that in the pronated position; (2) the stability of the humeroradial and humeroulnar joints was unaffected by the forearm's rotational position; and (3) a satisfactory range of motion of the elbow joint was obtained, with no complications.

Biceps tenodesis combined with rotator cuff repair increases functional status and elbow strength.

The aim of the present study was to prospectively evaluate the elbow flexion and supination strengths and the functional outcomes of patients following arthroscopic rotator cuff repair combined with simultaneous biceps tenodesis. 19 patients who underwent arthroscopic rotator cuff repair and biceps tenodesis with at least 24months of follow-up were included. Patients were evaluated using a visual analog scale (VAS) for bicipital groove pain, American Shoulder and Elbow Surgeons (ASES), and constant scores (CS), biceps apex distance (BAD), elbow flexion, and supination strengths. The VAS for biceps groove measurement averages in the postoperative 6th, 12th, and 24th months was lower in comparison to preoperative data and was considered to be statistically significant (p < .05). The constant score, an average of all postoperative measurements and scores, was found to be higher than preoperative values and was considered to be statistically significant (p < .01). There was a significant difference in the operated and non-operated forearm supination and elbow flexion muscle strength measurements at the postoperative 3- and 6-month follow-ups (p < .01). Arthroscopic biceps tenodesis into the anchors of the lateral row in combination with rotator cuff repair provides an increase in the strength of elbow flexion and forearm supination, while decreasing pain. Level IV.

Long head of biceps tenotomy versus tenodesis: a systematic review and meta-analysis of randomized controlled trials.

To compare tenotomy versus tenodesis for the treatment of long head of the biceps tendon pathologies. The primary outcome was the shoulder functional outcome. The secondary outcomes consisted of postoperative pain, elbow flexion and forearm supination strengths and postoperative complications. PubMed, MEDLINE, Google Scholar and Web of Science were searched until April 2020. Included studies were randomized controlled trials with a minimum 12 months' follow-up. Both treatments had similar improvement on the Constant-Murley score at 6 months and 12 months. However, tenotomy had a significantly lower Constant-Murley score at two years with a mean difference of -1.13 (95% confidence interval -1.9, -0.35). Furthermore, tenotomy had a risk ratio of 2.46 (95% confidence interval 1.66, 3.64) for developing Popeye's deformity. No significant difference was detected in other functional outcomes, pain, or elbow flexion and forearm strength indices. Tenodesis and tenotomy are both well-established techniques that similarly yield satisfactory outcomes. Despite that tenodesis had a statistically significant better Constant-Murley score at two years, this was clinically irrelevant. With the current evidence, we recommend either technique for the management of the long head of the biceps tendon pathologies. Therapeutic, Level II.

Associations between Subtalar Muscle Strength and Balance Performance in Healthy Young and Old Adults

Background: Associations between lower limb muscle strength and balance performance in adults have previously been reported. However, the function of the foot muscles for postural control has not been understood, yet. Objective: The purpose of the present study was to investigate associations between pronator and supinator muscle strength, subtalar range of motion (ROM) and postural stability while standing under various conditions in young versus old adults. Methods: Using a custom-built apparatus equipped with a force transducer and an electrogoniometer, maximum voluntary isometric subtalar pronator and supinator strength as well as ROM tests were administered to 30 young (mean age: 25.1 years) and 30 old (mean age: 65.2 years) volunteers. Total active subtalar ROM, peak pronator and peak supinator torques were measured. While standing on a force plate, limits of stability (LOS) were determined during anterior–posterior (AP) and medio-lateral (ML) leaning tasks. Furthermore, sway distance and velocity during single-legged standing were measured. Correlation and regression analyses were conducted. Results: In both age groups, subtalar pronator muscle strength was related to AP-LOS (young: r = 0.36; old: r = 0.49). In young adults, subtalar supinator muscle strength was associated with ML-LOS (r = 0.41). The regression analyses revealed that summed subtalar muscle strength predicts 13 and 20% of the variance of AP-LOS in young and old adults, respectively. Summed subtalar muscle strength was found to predict 18% of the variance in ML-LOS in young but not in old adults. There were no correlations and no predictors found concerning subtalar muscle strength and postural sway during single-legged standing for both age groups. Conclusions: Longitudinal studies have to proof whether pronator muscle strength training might positively affect balance performance during AP leaning, specifically in old adults.

Radius' Giant Cell Tumor: Allograft with Conservation of Distal Radioulnar Joint.

Purpose Giant cell tumor of the distal radius are frequent lesions, and different types of surgeries have been described. Functional results, after conservative treatment or arthrodesis, often find a decreased strength and range of motion. The sacrifice of the distal radioulnar joint could be one of the causes. We report the case of a 26-year-old patient who presented with a Campanacci Grade III giant cell tumor of the distal radius. We managed his case by the association of en bloc resection and allograft reconstruction with the preservation of distal radioulnar joint. Hypothesis This procedure could improve functional results, without increasing the risk of recurrence at 2 years follow-up. Case Report The originality of our technique was the possibility of distal radioulnar joint conservation. We preserved a long portion of cortex bone all through the ulnar side of the distal radius. We then used an allograft of distal radius, fixed by a reconstruction anatomical plate. Results At 2 years follow-up, the range of motion was 100° with 60° of palmar flexion, 40° of extension, 75° of pronation, and 70° of supination. Radial and ulnar inclination were 10 and 15°, respectively. MTS (Musculoskeletal Tumor Society Score) 1993 was 88% and DASH score was 6. Concerning grip strength, it was measured at 85% in comparison with the other side. Pronation and supination strengths were 80 and 73%, respectively, in comparison with the other side. At follow-up, standard X-rays showed no recurrence. The allograft was well integrated. Conclusion Conservative treatment of the distal radioulnar joint allowed an almost ad integrum recovery, concerning strengths and range of motion. It allows a better functional recovery, without increasing the risk of recurrence.

Immediate improvements of supination range of motion and strength following pronator teres muscle friction massage: a clinical trial comparing people with and without supination limited motion

ABSTRACTObjectives: To investigate the effects of friction massage techniques on the pronator teres muscle on supination range of motion (ROM) and supinator strength in individuals with and without limited supination ROM.Methods: In total, 26 subjects (13 with limited supination ROM and 13 healthy subjects) volunteered to participate in this study. We used a customized wrist cuff. Supination ROM and supinator strength were measured with a 9-axis inertial motion sensor and load cell. The friction massage protocol was executed with the pronator teres muscle in a relaxed position. Then supination ROM and supinator strength were measured again.Results: There was no significant interaction effect on supination ROM, which was significantly greater in the limited supination and control groups. A post hoc t-test revealed that the limited supination group achieved a significantly increased post-test supination ROM (51.7 ± 7.8°) compared to the pre-test value (43.6 ± 5.2°). In addition, the control group achieved a significant increase in post-test supination ROM (67.7 ± 10.0°) compared to the pre-test value (61.4 ± 7.7°). There was no significant interaction effect on supinator strength. Supinator strength was significantly greater in the limited supination and control groups. A post hoc t-test revealed a significant difference in supinator strength between the pre- and post-test values in the limited supination group.Discussion: Friction massage helps restore a limited ROM of the forearm supination motion and immediately increases supinator muscle strength. This technique can be used as an intervention method to improve muscle strength in patients with limited supination ROM.

Functional classification of grasp strategies used by hemiplegic patients.

This study aimed to identify and qualify grasp-types used by patients with stroke and determine the clinical parameters that could explain the use of each grasp. Thirty-eight patients with chronic stroke-related hemiparesis and a range of motor and functional capacities (17 females and 21 males, aged 25–78), and 10 healthy subjects were included. Four objects were used (tissue packet, teaspoon, bottle and tennis ball). Participants were instructed to “grasp the object as if you are going to use it”. Three trials were video-recorded for each object. A total of 456 grasps were analysed and rated using a custom-designed Functional Grasp Scale. Eight grasp-types were identified from the analysis: healthy subjects used Multi-pulpar, Pluri-digital, Lateral-pinch and Palmar grasps (Standard Grasps). Patients used the same grasps with in addition Digito-palmar, Raking, Ulnar and Interdigital grasps (Alternative Grasps). Only patients with a moderate or relatively good functional ability used Standard grasps. The correlation and regression analyses showed this was conditioned by sufficient finger and elbow extensor strength (Pluri-digital grasp); thumb extensor and wrist flexor strength (Lateral pinch) or in forearm supinator strength (Palmar grasp). By contrast, the patients who had severe impairment used Alternative grasps that did not involve the thumb. These strategies likely compensate specific impairments. Regression and correlation analyses suggested that weakness had a greater influence over grasp strategy than spasticity. This would imply that treatment should focus on improving hand strength and control although reducing spasticity may be useful in some cases.

Isokinetic evaluation of wrist muscle strength in patients of carpal tunnel syndrome.

This study aims to investigate the isokinetic characteristics of wrist strength in flexion, extension, supination, pronation, radial, and ulnar deviation in patients with moderate or severe carpal tunnel syndrome (CTS). Thirteen patients (23 hands) (2 males, 11 females; mean age 45 years; range 29 to 60 years) with moderate or severe CTS were compared to six healthy control subjects (12 hands) (2 males, 4 females; mean age 41 years; range 27 to 63 years) in this study, which was conducted between January 2016 and April 2016. Wrist flexion, extension, supination, pronation, radial, and ulnar deviation muscle strengths were measured at 30°/second (5 sets) angular velocity with isokinetic dynamometer. Grip strength was measured with hand dynamometer (kilograms). Boston Questionnaire was used for clinical assessment. Grip strength (p=0.003); wrist flexion 30°/second (p=0.014); extension 30°/second (p=0.016); and ulnar deviation 30°/second (p=0.017) muscle strengths were lower in CTS patients compared with the control group. An evaluation according to symptom duration did not reveal any significant relationship in any of the isokinetic tests with the exception of pronation 30°/second (p=0.039, r= -0.432) and ulnar deviation 30°/second (p=0.034, r=0.443) in CTS patients. No significant relationship was found between Boston Questionnaire, grip strength, and isokinetic test results. Quantitative wrist strength measurements with isokinetic dynamometers are beneficial in conservative exercise treatments and motor assessments of CTS patients.

Clinical outcomes and safety of distal biceps repair using a modified entry point.

The purpose of this study is to determine the safety of a one-incision technique for distal biceps repair with modified repair entry point in regards to the distance from the posterior interosseous nerve (PIN). Secondly, we present the clinical results of patients having undergone this procedure. Ten cadaveric specimens were dissected to reveal the radial tuberosity. Two 1.6-mm guidewires were inserted into the radial tuberosity, one centrally, and one 5-mm more proximal. Both guidewires penetrated the dorsal cortex, and posterior dissection revealed their exit points. The distance from the PIN and each wire was determined using a vernier calliper. The functional outcomes of 10 patients' post repair were reviewed. Performance was determined using strength and range of motion (ROM) measurements. Functional impairment was assessed using the disability of the arm, shoulder and hand outcome measure (DASH score). The uninjured side was used as a control. The mean distance from the centre of the radial tuberosity to the PIN was 7.33 mm with a centrally placed wire, compared with 10.92 mm when measuring from the proximal guidewire (P < 0.05). Supination and flexion strengths were 83 and 90% of the uninjured side, respectively. There was a mean of 1.5° loss of flexion and 0° loss of extension. Loss of pronation and supination ROM were 0.5° and 4.5° on average, respectively. Average DASH score was 6.3. We recommend a 5-mm more proximal entry point for insertion of the guidewire during distal biceps repair. This poses less risk to the PIN without significant functional impairment. Our outcomes are comparable with those reported in the literature.

The angle-torque-relationship of the subtalar pronators and supinators in male athletes: A comparative study of soccer and handball players.

It is currently unclear how participation in different sports affects the angle-specific subtalar pronator and supinator muscle strength and pronator-to-supinator strength ratio (PSR). Based on the hypothesis that both differences sport-related patterns of play and foot-ground interaction may lead to sport-specific muscle adaptations, this study compared the angle specific pronator and supinator strength capacity of handball and soccer players. Eighteen healthy male handball and 19 soccer players performed maximum isometric voluntary isometric contractions using a custom-made testing apparatus. Peak pronator (PPT) and supinator torques (PST), pronator and supinator strength curves (normalised to the peak torque across all joint angles) and PSR were measured in five anatomical joint angles across the active subtalar range of motion (ROM). All analysed parameters were dependent on the subtalar joint angle. The ANOVA revealed significant `joint angle' × `group' interactions on PPT, pronator strength curves and PSR. No group differences were found for active subtalar ROM. In previously uninjured handball and soccer athletes, there were intrinsic differences in angle-specific subtalar pronator muscle strength. The lower PSR, which was found in the most supinated angle, can be seen as a risk factor for sustaining an ankle sprain.

Direct repair of chronic distal biceps tendon tears

ObjectiveTo present the results from direct tendon repair using EndoButton and interference screws in patients with lesions of the distal biceps that had evolved over a period of more than 28 days. MethodsBetween January 2012 and November 2013, eleven patients (all male) with a torn distal biceps and a time interval between injury and surgery of more than 28 days were evaluated. The patients’ mean age was 46 years and the most common mechanism of injury was eccentric loading with the elbow flexed and supinated. ResultsA subjective analysis on pain and function was conducted using a visual analog scale of pain (VAS) and the Mayo Elbow Performance Score (MEPS), before and after surgery. The VAS showed a decrease of 5 points to 0.8 points on average. The MEPS improved from 69.3 points before the operation to 97.5 points afterwards. The mean flexion was 133.1° on the operated side, versus 134.3°. The mean extension was −2.5° and 0° (operated side versus non-operated). Supination was 88.2° versus 89.5° and pronation was 82.5° versus 84.1°, comparing the operated side versus the non-operated side. Flexion and supination strengths were evaluated with the aid of a dynamometer, and the mean flexion and supination strengths were found to be respectively 78.57% and 89.65% of the strength of the non-operated limb. ConclusionUse of the technique of direct tendon repair using EndoButton and interference screws was shown to be a safe and effective alternative for repairing chronic lesions of the distal biceps.

Intermediate term evaluation of the Eclypse distal radio-ulnar prosthesis for rheumatoid arthritis. A report of five cases

HypothesisEarly medical management of rheumatoid arthritis with biotherapy has changed the traditional musculoskeletal damage from this disease. When the distal radio-ulnar joint (DRUJ) is involved, classic procedures may be inappropriate. We chose a hemi-arthroplasty of the DRUJ joint (Eclypse™) in patients with persistent synovitis and chondrolysis with a stable joint. The aim of this study was to assess the intermediate term results of this approach in these specific cases. Materials and methodsWe report a retrospective study of 5 Eclypse arthropasties implanted between March 2005 and March 2011. There were 4 women and 1 man, mean age: 58.4years old (54–62) with RA that had been present for 21.6years (15–33). This hemi-arthroplasty replaced the ulnar head with a pyrocarbon component. Patients were evaluated by an independent observer for pain by VAS, range of motion, grip strength in the neutral position by Jamar dynamometer, pronation and supination strengths with a pronosupinator, DASH score and wrist X-rays. ResultsOne patient was lost to follow-up and the 4 others underwent a follow-up evaluation at 64 months (43–90). There were no intra-operative or postoperative complications. The pain score at the final follow-up was 1.5/10 (0–4), pronation was 70° (60–80) and supination was 80° (80–80). Grip strength was 148% compared to the contralateral side (73–200%). Pronation and supination strengths were 1.7kg (1.5–2) and 2.1kg (2–2.5) respectively. The DASH score was 55.9 points (42.6 to 79.3). X-rays did not show any changes in the ulnar notch. ConclusionThis distal radio-ulnar arthroplasty is less invasive and preserves the bone and ligaments. Clinical results are rapid, remain stable over time and are well tolerated. This arthroplasty, which was initially developed for osteoarthritis and traumatic lesions of the DRUJ, is promising for specific cases of rheumatoid arthritis.

Distal biceps brachii tendon repair: a systematic review of patient outcome determination using modified Coleman methodology score criteria.

This systematic literature review evaluated the methodological research design quality of studies that evaluated patient outcomes following distal biceps brachii tendon repair and developed evidence-based recommendations for future patient clinical outcomes research. Following the preferred reporting items for systematic reviews and meta-analyses criteria, and using "biceps brachii", "tendon", "repair" and "outcome assessment" search terms, the CINAHL, Academic Search Premier and MEDLINE databases were searched from January 1960-October 2015. The modified Coleman methodology score (MCMS) served as the primary outcome measure. Descriptive statistical analysis was performed for composite and component MCMS and for patient outcome assessment methodology use frequency. A total of 93 studies were evaluated. Overall MCMS was low (57.1±14). Only 12 (12.9%) had prospective cohort or randomized controlled trial designs. There was a moderate relationship between publication year and MCMS (r=0.53, P<0.0001). Although 61 studies (65.6%) had adequate surgical descriptions, only 3 (3.2%) had well-described rehabilitation. Of 2253 subjects, only 39 (1.7%) were women. Studies published after 2008 had higher MCMS scores than studies published earlier (61.3±10 versus 52.9±16, P=0.003). Although overall research study methodological scores improved on average since 2008, generally low MCMS scores, retrospective designs, lack of eccentric elbow flexor or supinator strength testing, and poorly described surgical and rehabilitation descriptions remain commonplace. These findings decrease clinical study validity and generalizability. III.

Reparo direto das lesões distais crônicas do tendão bicipital

ObjectiveTo present the results from direct tendon repair using EndoButton and interference screws in patients with lesions of the distal biceps that had evolved over a period of more than 28 days. MethodsBetween January 2012 and November 2013, eleven patients (all male) with a torn distal biceps and a time interval between injury and surgery of more than 28 days were evaluated. The patients’ mean age was 46 years and the most common mechanism of injury was eccentric loading with the elbow flexed and supinated. ResultsA subjective analysis on pain and function was conducted using a visual analogue scale of pain (VAS) and the Mayo Elbow Performance Score (MEPS), before and after surgery. The VAS showed a decrease of 5 points to 0.8 points on average. The MEPS improved from 69.3 points before the operation to 97.5 points afterwards. The mean flexion was 133.1° on the operated side, versus 134.3°. The mean extension was −2.5 degrees and zero degrees (operated side versus non‐operated). Supination was 88.2° versus 89.5° and pronation was 82.5° versus 84.1°, comparing the operated side versus the non‐operated side. Flexion and supination strengths were evaluated with the aid of a dynamometer, and the mean flexion and supination strengths were found to be respectively 78.57% and 89.65% of the strength of the non‐operated limb. ConclusionUse of the technique of direct tendon repair using Endobutton and interference screws was shown to be a safe and effective alternative for repairing chronic lesions of the distal biceps.

Development of a functional anatomical subtalar pronator and supinator strength training machine

The strength training industry has failed in designing a machine for exercising the pronators and supinators, despite their substantial medio-lateral bracing function. The present study documents the muscle strength generation capabilities of the pronators and supinators within their functional anatomic movement plane, using an innovative strength training machine with an oblique axis. By using two force transducers, the angle-torque relationship of the pronators and supinators of 18 healthy male subjects was identified during maximum voluntary isometric contractions at five anatomical joint angles. Surface EMG was recorded from anterior tibial (TA), peroneus longus (PL) and soleus (SOL) muscles. The pronator strength curve showed an inverted U-shaped characteristic, whereas the supinator curve descends from pronated to supinated position. Compared to the muscle activities for one-leg heel raise and toe raise, PL (108-131%) and TA (59-83%), respectively, showed highest activity during pronations. The most activated supinator is SOL (67% of a one-leg heel raise). Differences in the shape of the pronator and supinator strength curves revealed that two different variable cams have to be implemented for matching the human torque capability. We anticipate our study to be a starting point for preventive machine-based training interventions.

Early Versus Delayed Fourth Ray Amputation With Fifth Ray Transposition for Management of Mutilating Ring Finger Injuries

To compare hand function after early versus delayed fourth ray amputation and transposition of the fifth ray in mutilating ring finger injuries. We prospectively compared 2 groups of patients who sustained either isolated mutilating ring finger or complex hand injuries between January 2008 and December 2013. The first group (12 patients; 10 male and 2 female) was managed by early (within 14 d) fourth ray amputation with fifth ray transposition, and the second group (13 patients; 9 male and 4 female) was managed similarly but on a delayed basis (after 20 d). The postoperative fifth metacarpophalangeal joint active range of motion was recorded and compared with the preoperative value. Function was evaluated by measuring grip and key pinch strengths, supination and pronation strengths, and hand breadth. All parameters were evaluated by comparing the injured and the noninjured hands. Group 1 patients exhibited superior results to group 2 patients regarding the postoperative grip and key pinch strength and pronation and supination strength in addition to the mean postoperative active range of motion of the transposed ray metacarpophalangeal joint. However, the results were statistically significant regarding only grip and pronation strengths. Postoperative active range of motion of the transposed ray metacarpophalangeal joint was significantly reduced in the cases having preoperative compromise of the transposed digit in group 1. The final subjective cosmetic satisfaction was better in group1. Our results support early fourth ray amputation with fifth ray transposition for mutilating ring finger injuries. Therapeutic II.

Angle-torque relationship of the subtalar pronators and supinators in younger and elderly males and females.

BackgroundThe angle-dependent torque capacity of the subtalar pronators and supinators is important to maintain dynamic ankle stabilisation. Based on the peak torques during maximum voluntary isometric pronation and supination across the subtalar range of motion, the strength curves of younger and elderly males and females were investigated.MethodsMaximum voluntary isometric subtalar pronator and supinator strength tests were administered to 30 younger and 30 elderly volunteers (each 15 male and 15 female subjects). Total active subtalar range of motion and peak pronator and supinator torques were measured in five anatomical subtalar joint angles using a custom-built apparatus with two force transducers. Furthermore, relative torques (normalised to the individual peak torque) and pronator-to-supinator strength-ratios were also calculated.ResultsPronator-to-supinator strength ratio, and peak pronator and supinator torques are affected by age and by joint angle x age interactions. All supinator strength curves show a steadily descending characteristic from the pronated to the supinated positions. The pronator strength curve had an inverted U-shaped characteristic, except for younger women of whom 47 % exert highest peak values in the end-range pronation angle. Both relative pronator and supinator strength are dependent on sex (P < 0.05). Relative pronator strength is also affected by joint angle x sex (P < 0.0001) and joint angle x sex x age (P < 0.05) interactions. Beside age effects on all range of motion parameters, pronation range of motion is influenced by a sex x age interaction (P < 0.05).ConclusionsAge- and sex-related differences in both subtalar strength profile and range of motion have to be considered when testing strength across subtalar range of motion. Younger females have higher pronator strength capacity in the most pronated joint angle, which may be due in part to their greater subtalar joint range of motion compared to the other groups. In the most supinated position both pronator and supinator strength capacity is reduced in younger females compared to younger males.Electronic supplementary materialThe online version of this article (doi:10.1186/s13047-015-0125-2) contains supplementary material, which is available to authorized users.

Reliability of isometric subtalar pronator and supinator strength testing.

BackgroundDue to the specific anatomy of the subtalar joint with its oblique axis, isometric pronator and supinator strength is not well documented. The purpose of this study was to determine intra- and between-session reliability of pronator and supinator strength and lower leg muscle activity measurements during maximum voluntary isometric contractions (MVIC).MethodsPronator and supinator peak torques (PT), with and without supplementary visual muscle strength biofeedback (FB), and muscular activities of peroneus longus (PL) and tibialis anterior (TA) were assessed twice 3 days apart by the same examiner in 21 healthy young male adults (mean age: 27.6 years; SD = 3.9). Limits of agreement (LoA) and minimum detectable change (MDC) were evaluated.ResultsBy applying FB, reliability of both pronator and supinator PT was improved: LoA were reduced from 32% to 26% and from 20% to 18% and MDC from 20% to 15% and from 16% to 12% in supinator and pronator PT, respectively. Learning effects in pronator and supinator PT (p < 0.05), which were present without FB, were eliminated using FB. Except for TA during pronation, muscle activities showed low reliability indicated by LoA of 51% to 79%.ConclusionsUsing supplementary biofeedback, isometric subtalar pronator and supinator strength testing is reliable in healthy subjects. LoA of 18% and 26% have to be exceeded for pronator and supinator PT, respectively, to detect relevant effects in repeated measures.

HIGH RESISTANCE SHANK MUSCLE STRENGTH TRAINING CHANGES FOOT BEHAVIOUR DURING A SUDDEN ANKLE SUPINATION

BackgroundChronic lateral ankle instability afflicts many athletes. The peroneal muscles are the most effective lateral stabilizers whose strength increase might brace the ankle joint complex laterally. Purpose of this study...

Isokinetic evaluation of pronation after volar plating of a distal radius fracture

Introduction Pronator quadratus (PQ) is an important contributor to forearm pronation, and there is concern that volar plating of a distal radius fracture (DRF) may damage the PQ function. The purpose of this study was to determine whether isokinetic pronation strength would decrease considerably after volar locking plating of a DRF, and whether clinical outcomes would be affected by any pronation strength decrease. Materials and methods Thirty-four patients of mean age of 55 years (range, 21–74 years) underwent bilateral isokinetic testing at 6 months and 1 year after open reduction and internal fixation using volar plating. Isokinetic pronation and supination strengths were compared between the operated and normal sides. Clinical outcomes such as grip strengths, range of motions and disabilities of the arm, shoulder and hand (DASH) scores were evaluated and analysed for any associations with isokinetic results. Results At 6 months, peak torque and total work values for both pronation and supination were lower in the operated sides than in the normal sides (all p < 0.001). However, at 1 year postoperatively, the differences in pronation strength were not statistically significant ( p = 0.188 for peak torque and p = 0.190 for total work), whilst supination torque and total work were still significantly lower in the operated sides ( p = 0.015 and p = 0.029, respectively). Decreases in pronation strength were found to correlate significantly with decreases in supination strength and grip power. Wrist motion and DASH scores were not found to be correlated with decrease in pronation or supination strengths. Conclusions In patients with a DRF treated by volar plating, pronation strength was not significantly different between the operated and normal sides at 1 year postoperatively, and decreases in pronation or supination strengths were not found to affect clinical outcomes as assessed by DASH scores. This study suggests that dissection of the PQ may have minimal clinical impact on forearm pronation function.