Review and comparison of linear algorithms to quantify muscle fatigue based on sEMG signals.

Surface electromyography techniques are widely used in field of motion analysis and ergonomics combining precise muscular activation assessment with low-invasiveness and wearability. The aim of this investigation is to identify the myoelectrical manifestations of fatigue and to compare the effectiveness of sEMG-based quantitative indices for fatigue assessment. The investigated indexes are the ARV and RMS signal amplitudes, the mean frequency, the median frequency, the Dimitrov index, the instantaneous mean frequency and Wavelet distribution-based WIRE51 index. Two different protocols were developed, and the activity of the lateral deltoid and middle trapezius muscles was recorded. The WIRE51 index is found to have the highest sensitivity in the detection of the difference between the repetitions of each exercise for both protocols. Due to the lack of a unified standard for the performance comparison of fatigue indices, a correlation analysis was carried out between the result provided by the indices and the subjective fatigue perception employing the RPE scale.

The aim of this study is to compare quantitative indices for assessing muscular fatigue from the sEMG acquisitions. The assessment is accomplished with an experimental investigation of ten subjects and two repetitive movement types. The best performing indices are found to be the WIRE51 and the Dimitrov ones.

Acromiohumeral distance changes with posture in healthy adults and patients while wearing a shoulder abduction brace.

[Purpose] To examine the humeral head positions while wearing an abduction brace in the sitting and supine positions in healthy adults and patients who have been operated on for shoulder joint diseases. [Participants and Methods] Thirty participants were included in the study, of which 15 were healthy adults (without any orthopedic diseases) and 15 had shoulder diseases (post-arthroscopic repair of a rotator cuff tear). The acromion and humeral head were observed on ultrasound. The acromiohumeral distance was measured once in two different positions while wearing the brace: edge sitting and supine. [Results] The mean acromiohumeral distance in the healthy group was 7.9 ± 1.1 mm while sitting and 7.2 ± 1.0 mm in the supine position. In the disease group it was 7.6 ± 0.9 mm while sitting and 6.3 ± 1.1 mm in the supine position. Multiple logical regression revealed that the acromiohumeral distance was not affected by the participant's age, height, or weight. [Conclusion] The acromiohumeral distance was significantly reduced in the supine position despite the use of an abduction brace. Therefore, patients must use a pillow/towel to support the shoulder joint to prevent unnecessary stress while the cuff tendons are healing.

Latissimus dorsi tendon transfer to restore shoulder abduction in patients with deltoid paralysis: A novel technique.

Background: Shoulder abduction is an essential movement for placement of the hand in space and thus for upper limb function. The objective of this study was to introduce and test the effectiveness of a new technique of latissimus dorsi tendon transfer to deltoid insertion to restore shoulder abduction. Methods: We prospectively included 10 male patients with a lost deltoid function. Their mean age was 34.6 years (range, 25-46). We describe a new technique to compensate for the loss of the deltoid function using a latissimus dorsi tendon transfer augmented with a semitendinosus tendon graft. The tendon graft is passed over the acromion and attached to the anatomical deltoid insertion. Postoperatively, a shoulder spica in 90° abduction was used for six weeks followed by physiotherapy. Results: Patients were followed up for a mean of 25.4 months (range, 12-48). The mean range of active shoulder abduction rose to 110° (range, 90-140°) with a mean gain of 83° of abduction. Conclusions: This procedure can be a useful technique for restoration of a significant range and strength of active shoulder abduction.

Posterior division of ipsilateral C7 transfer to C5 for shoulder abduction limitation.

Background: Reparation of C5 by proximal selective ipsilateral C7 transfer has been reported for the treatment of neurogenic shoulder abduction limitation as an alternative to the reparation of the suprascapular nerve (SSN) and the axillary nerve (AXN) by distal nerve transfers. However, there is a lack of evidence to support either strategy leading to better outcomes based on long-term follow-up. Objective: The purpose of the study was to investigate the safety and long-term outcomes of the posterior division of ipsilateral C7 (PDIC7) transfer to C5 in treating neurogenic shoulder abduction limitation. Methods: A total of 27 cases with limited shoulder abduction caused by C5 injury (24 cases of trauma, 2 cases of neuritis, and 1 case of iatrogenic injury) underwent PDIC7 transfer to the C5 root. A total of 12 cases (11 cases of trauma and 1 case of neuritis) of C5 injury underwent spinal accessory nerve (SAN) transfer to SSN plus the triceps muscular branch of the radial nerve (TMBRN) transfer to AXN. The patients were followed up for at least 12 months for muscle strength and shoulder abduction range of motion (ROM). Results: In cases that underwent PDIC7 transfer, the average shoulder abduction was 105.9° at the 12-month follow-up. In total, 26 of 27 patients recovered at least M3 (13 reached M4) (Medical Research Council Grading) of the deltoid. In cases that underwent SAN transfer to SSN plus TMBRN to AXN, the average shoulder abduction was 84.6° at the 12-month follow-up. In total, 11 of 12 patients recovered at least M3 (4 reached M4) of the deltoid. Conclusion: Posterior division of ipsilateral C7 transfer is a one-stage, safe, and effective surgical procedure for patients with neurogenic shoulder abduction limitation.

Phrenic Nerve as an Alternative Donor for Nerve Transfer to Restore Shoulder Abduction in Severe Multiple Root Injuries of the Adult Brachial Plexus.

PURPOSE: Nerve transfer is the gold standard to restore shoulder abduction in acute brachial plexus injuries. The aim of this study was to compare the phrenic nerve (Ph) to the spinal accessory nerve (XI) as the donor nerve for this purpose. METHODS: A retrospective chart review was performed on 136 patients with acute brachial plexus injuries who received a nerve transfer of the shoulder with either the Ph (94 patients) or XI (42 patients). Each group was divided into 3 subgroups based on the recipient nerve. The maximum degree of shoulder abduction was recorded after 2 years of postoperative follow-up. A generalized estimating equation model was performed to examine the variables affecting shoulder abduction over time. RESULTS: The maximum degrees of shoulder abduction achieved were 61.9° ± 38.7° in patients with Ph and 51.1° ± 37.3° in patients with XI. More than M3 shoulder abduction was achieved by 67% of patients with Ph versus 59% of patients with XI. The regression analysis showed that the age at the time of surgery correlated more with the functional outcome over time than the choice of donor nerve. CONCLUSIONS: In multiple root brachial plexus injuries, the Ph exhibited similar outcomes to the XI for shoulder abduction. Our routine exploration of the supraclavicular plexus exposes the Ph conveniently for nerve transfer. The phrenic nerve should be considered as an alternative when the XI is not available or is reserved for secondary reconstruction. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Altered muscle recruitment patterns during isometric shoulder abduction in individuals with chronic upper trapezius pain: a cross sectional study.

BACKGROUND: Upper trapezius (UT) pain with myofascial trigger points (MTrPs) can affect movement at the glenohumeral joint as well as at the scapulothoracic joint. The investigation of muscle recruitment patterns can discern motor control strategies. The purpose of this study was to compare shoulder muscle recruitment patterns and muscle activity according to various loads between individuals with and without chronic UT pain. METHODS: In this cross-sectional study, twenty-four participants that had UT pain with MTrPs and sex, age, body weight matched 24 controls with no UT pain were recruited. Surface EMG electrodes were attached to the UT, the serratus anterior (SA), the lower trapezius (LT) and the middle deltoid (MD). All participants performed isometric shoulder abduction with a load of 25%, 50%, or 75% of the maximum strength at 60° of shoulder abduction. The EMG activity, the activity ratio (SA/UT, LT/UT, MD/UT), and the relative contribution of each muscle activity were calculated. RESULTS: MD activity was significantly decreased in the UT pain group compared to that in the control group (p < 0.05). The EMG activity ratio of SA/UT (p < 0.025) and the relative contribution of SA activity to shoulder abduction (p < 0.05) were significantly greater in the UT pain group than in the control group in the 25% loading condition. CONCLUSION: The results of present study showed that UT pain with MTrPs may increase the relative contribution of SA activity and decrease MD activity at low loads. Altered recruitment patterns of scapular upward rotators can be altered in the proper scapular position, which results in decreased MD activity. Clinicians should consider altered recruitment patterns when managing UT pain. TRIAL REGISTRATION: Clinical Research Information Service: Clinical Research Information Service (KCT0007370; 08/06/2022).

Age correlation in upper brachial plexus injury patients undergoing nerve transfer surgeries.

•A patient's age can be a critical factor influencing the outcome following upper brachial plexus injury (BPI) reconstruction.•The favorable factor being younger patients with short denervation period.•In older patients early and more aggressive management for an optimal outcome.•This study supports the various correlation of age with the outcomes of upper brachial plexus reconstruction surgery.

The effects of operating height and the passage of time on the end-point performance of fine manipulative tasks that require high accuracy.

Sustained shoulder abduction, which results from an inappropriate worktable height or tool shape and long task hours, leads to an accumulation of muscle fatigue and subsequent work-related injuries in workers. It can be alleviated by controlling the table height or ergonomic tool design, but workers who are doing some types of work that require a discomfortable posture, such as minimally invasive surgery, cannot avoid these situations. Loads to the shoulder joint or muscles result in several problems, such as muscle fatigue, deterioration of proprioception or changing movement strategies of the central nervous system, and these are critical to work that requires a high accuracy of the upper extremities. Therefore, in this paper, we designed and conducted an experiment with human participants to discuss how an inappropriate height of the work-table affects the task performance of workers who are performing a fine manipulative task that requires high accuracy of the end point. We developed an apparatus that can control the height and has four touch screens to evaluate the end-point accuracy with two different heights. Eighteen adults (9 women and 9 men) participated in the experiments, and the electromyography of their shoulder muscles, their movement stability, and task performance were measured for the analysis. We found that inappropriate height of a table brings about muscle fatigue, and time elapsed for conducting tasks accelerated the phenomenon. Task performance deteriorated according to increased fatigue, and improved movement stability is not enough to compensate for these situations.

The Demography of Traumatic Brachial Plexus Avulsion Injuries.

Background and objective Brachial plexus injuries more commonly affect the younger generation who constitute the productive workforce. The patients who sustain avulsion injuries of the brachial plexus are more often involved in high-velocity accidents. The avulsion injuries are surgically managed by nerve transfers. This study aimed to evaluate the demography of brachial plexus avulsion injuries. Materials and methods This retrospective study was conducted in January 2013 and included 21 patients treated from January 2007 to December 2011. Results Of the 21 patients, 20 were male and the most commonly affected patients were in the age group of 21-30 years. The mean age of the affected patients was 27.24 years. Six of the patients had pan palsy (C5-8 and T1), nine had C5-7 injury, and six had C5-6 injury. Twenty patients underwent spinal accessory to suprascapular nerve transfer, nine patients underwent ulnar nerve fascicle to nerve to biceps branch transfer, and one patient underwent intercostal nerve to musculocutaneous nerve transfer. Of note, 40% of the patients regained more than M3 power for abduction and external rotation of the shoulder, and 30% of the patients regained more than M3 power for elbow function. Conclusions Road traffic accidents are the most common cause of brachial plexus injuries. Nerve transfers for shoulder and elbow function play a significant role in improving the function of the upper extremity.

Comparative accuracy of a shoulder range motion measurement sensor and Vicon 3D motion capture for shoulder abduction in frozen shoulder.

BACKGROUND: Although patients with frozen shoulders have the range of motion (ROM) of their shoulder's abduction movements measured at hospital and the physical therapy visits, multiple visits to check for progress is often difficult. Thus, we developed an artificial intelligence-based image recognition detectable sensor (AIRDS) intended for easy use at home. OBJECTIVE: The purpose of this study was to determine the accuracy of a sensor (AIRDS) measuring shoulder abduction angle, thus offering a valid and feasible system for monitoring patients with frozen shoulder. METHODS: Ten patients with frozen shoulder (5 males, 5 females) performed shoulder joint movements while being measured with the AIRDS system and the 3-dimensional Vicon system. The measure of the outcome included the linear regression of the shoulder abduction joint kinematics. RESULTS: Linear regression analysis of the AIRDS system and the Vicon system demonstrated a significant correlation coefficient of R2= 0.9979 (P< 0.05). CONCLUSIONS: Our results provide novel, promising evidence that AIRDS can accurately measure the timing and total spatial characteristics of clinical movements. AIRDS is designed to provide real-time ROM measurements for joint mobility using artificial intelligence instead of the judgement of the physical therapist.

A biomechanical study on the effect of long head of biceps tenotomy on supraspinatus load and humeral head position during shoulder abduction.

INTRODUCTION: The purpose of this study was to determine the effect of biceps tendon tenotomy on the load of the supraspinatus tendon/muscle complex during abduction of the arm from 0° to 15°. METHODS: Eleven fresh frozen human cadaver shoulders (6 males, 5 females, age ranged 44-88 years, mean upper extremity weight 2.96 ± 0.56 kg) were included. The specimens were sequentially mounted onto a custom-made fixture attached to a pulley system and load cell. The pulley system was used to pull the supraspinatus tendon/muscle complex along its fiber directions to abduct the arm to 15°. Abduction angles were recorded with a digital inclinometer. Two conditions were tested: (1) long head biceps tendon (LHBT) intact and in normal anatomical position; (2) LHBT cut within the bicipital groove. Qualitative visual inspection of humeral head displacement during abduction was also included. Descriptive statistics were calculated. The Shapiro-Wilk test was used to establish normal data distribution, and the paired t-test was used to compare the 2 conditions. RESULTS: For the intact condition (LHBT intact), the mean load was 45.71 ± 21.04 N. For the biceps tenotomy test, the load measured 41.37 ± 23.43 N. These differences were not significant (P = .1480). In the tenotomy condition, the humeral head initially displaced inferior, and with initiation of abduction, the humeral head translated superior to its normal position. CONCLUSION: The results suggest that the LHBT has no critical role with initial abduction of the arm. Furthermore, the LHBT does not appear to increase loads required for the supraspinatus muscle/tendon complex to perform the same action of abduction.

Possible donor nerves for axillary nerve reconstruction in dual neurotization for restoring shoulder abduction in brachial plexus injuries: a systematic review and meta-analysis.

Restoring shoulder abduction is one of the main priorities in the surgical treatment of brachial plexus injuries. Double nerve transfer to the axillary nerve and suprascapular nerve is widely used and considered the best option. The most common donor nerve for the suprascapular nerve is the spinal accessory nerve. However, donor nerves for axillary nerve reconstructions vary and it is still unclear which donor nerve has the best outcome. The aim of this study was to perform a systematic review on reconstructions of suprascapular and axillary nerves and to perform a meta-analysis investigating the outcomes of different donor nerves on axillary nerve reconstructions. We conducted a systematic search of English literature from March 2001 to December 2020 following PRISMA guidelines. Two outcomes were assessed, abduction strength using the Medical Research Council (MRC) scale and range of motion (ROM). Twenty-two studies describing the use of donor nerves met the inclusion criteria for the systematic review. Donor nerves investigated included the radial nerve, intercostal nerves, medial pectoral nerve, ulnar nerve fascicle, median nerve fascicle and the lower subscapular nerve. Fifteen studies that investigated the radial and intercostal nerves met the inclusion criteria for a meta-analysis. We found no statistically significant difference between either of these nerves in the abduction strength according to MRC score (radial nerve 3.66 ± 1.02 vs intercostal nerves 3.48 ± 0.64, p = 0.086). However, the difference in ROM was statistically significant (radial nerve 106.33 ± 39.01 vs. intercostal nerve 80.42 ± 24.9, p < 0.001). Our findings support using a branch of the radial nerve for the triceps muscle as a donor for axillary nerve reconstruction when possible. Intercostal nerves can be used in cases of total brachial plexus injury or involvement of the C7 root or posterior fascicle. Other promising methods need to be studied more thoroughly in order to validate and compare their results with the more commonly used methods.

Upper extremity nerve transfers for acute flaccid myelitis: a systematic literature review.

BACKGROUND: Acute flaccid myelitis (AFM) is a rare disease that commonly affects young children. AFM's pathophysiology involves loss of lower motor neurons following a viral infection and induces acute asymmetric flaccid paralysis most commonly in the upper extremities. Nerve transfers have emerged as a treatment option for these patients with permanent motor deficits. OBJECTIVE: To summarize the literature and report safety and efficacy outcomes following nerve transfers for recovery of shoulder abduction and external rotation, and elbow flexion and extension in pediatric patients with AFM. Recovery of at least antigravity function was defined as a successful outcome. This systematic review was performed according to the PRISMA guidelines. The PubMed, Embase and Cochrane databases were utilized. RESULTS: Five studies comprising 44 patients (median age 2.95 years; 71% male), and 93 upper extremity nerve transfers were included. Thirty-eight patients received 65 nerve transfer procedures aiming for recovery of shoulder abduction and/or external rotation with a transfer to the axillary and/or suprascapular nerve. The recovery of shoulder abduction and external rotation was achieved in 40.7% (n = 11/27) and 60% (n = 6/10) of patients, respectively. Time from injury to surgery showed an inverse relationship with the odds for successful recovery (OR: 0.81; 95% CI: 0.64-1.02; p = 0.07); however, statistical significance was not reached. Successful recovery of elbow flexion with a transfer to the musculocutaneous was reported at a rate of 92.3% (n = 12/13). Successful re-innervation of the radial nerve with recovery of elbow extension was found in 75% (n = 6/8) of patients. No complications were reported. CONCLUSIONS: Upper extremity nerve transfers appear to be promising and safe for AFM patients. Shoulder abduction is the most challenging upper extremity function to recover. Further studies are warranted to identify whether nerve transfers are associated with superior outcomes when performed earlier.

Glenohumeral abduction contractures after residual neonatal brachial plexus injury.

Glenohumeral abduction contractures are common in patients with neonatal brachial plexus injury, but little has been previously published about them. We conducted a retrospective analysis of data prospectively collected from 205 consecutive children (108 female) of mean age 9.6 years with neonatal brachial plexus injury (C5-C6, 58%; C5-C7, 29%; C5-T1, 14%). Most children (69%) showed a glenohumeral abduction contracture, it being more common in those with upper neonatal brachial plexus injury.Level of evidence: III.

Shoulder abduction reconstruction for C5-7 avulsion brachial plexus injury by dual nerve transfers: spinal accessory to suprascapular nerve and partial median or ulnar to axillary nerve.

Results of shoulder abduction reconstruction in partial upper-type brachial plexus avulsion injuries are better when a triceps nerve is transferred to the axillary nerve in addition to the spinal accessory to suprascapular nerve transfer. However, in C5-7 avulsion injuries, the triceps nerve may be unavailable as a donor nerve. We report the results of an alternative neurotization to the axillary nerve using either a partial median or ulnar nerve. Patients with C5, 6 ± 7 avulsion injuries and weak triceps who underwent dual nerve transfers for shoulder abduction reconstruction were recruited for the study. The second neurotization to the axillary nerve was from either a partial median or ulnar nerve that had an expandable muscle innervation of ≥ M4 motor power. Patients were assessed for recovery of shoulder abduction and external rotation. Nine patients (median age = 23 years) underwent these dual neurotizations from March 2005 to April 2013. The median time to surgery was 4.5 months. Recovery of shoulder abduction averaged 114.4° (range 90°-180°) and external rotation averaged 136.3° (range 135°-140°). Final shoulder abduction power was > M3 in all 9 patients and ≥ M4 in 6 patients. One patient with partial median nerve transfer had transient hypoaesthesia in his thumb and index finger and another had a residual M4 power in his thumb and index finger flexors. In C5-7 avulsion injuries, dual nerve transfers of the spinal accessory to suprascapular nerve and partial median or ulnar nerve to axillary nerve are good options for shoulder abduction reconstruction with minimal morbidity. Level of evidence is level IV.

Systematic Review With Meta-Analysis: Are Muscle Transfers a Satisfactory Treatment Option to Restore Shoulder Abduction in Delayed Adult Brachial Plexus Injuries?

Brachial plexus injuries usually result in significant upper limb disabilities and shoulder joint instability. Primary nerve reconstruction procedures are more effective if performed within six months from the injury. Secondary procedures, including muscle transfers, are usually indicated for delayed presentation (>6 months) or when the outcomes of primary procedures are unsatisfactory. A comprehensive systematic search of the MEDLINE, EMBASE, AMED, PubMed, and Cochrane databases was conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data, including demographic information, time to surgery, the extent of brachial plexus injury, surgical techniques, follow-up duration, and functional outcomes were collected and tabulated. Meta-analysis was conducted using Review Manager (RevMan) 5.4 software ([Computer program]. Version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Seven studies were eligible to be included in this review, with a total of 218 patients. The average patient age was 28.39 ± 3 years, with a mean time to surgery of 29.87 ± 18 months. Forty-six (46) patients (21.10%) were treated as delayed presentation and 172 patients (78.89%) had muscle transfer performed as a secondary procedure. The mean time at follow-up was 18.86 ± 13.5 months. Upper trapezius muscle transfer was the most common transferred muscle (100%) either in isolation (n=159, 72.93%) or in combination with lower trapezius transfer (n=59, 27.06%). The mean preoperative and postoperative shoulder abduction were 12.22 ± 10.09 degrees and 58.36 ± 32.33 degrees, respectively (p < 0.05). Meta-analysis shows a statistically significant difference (CI at 95%, p<0.05) favoring postoperative shoulder abduction. Muscle transfers especially upper trapezius transfer could be a satisfactory secondary procedure to restore shoulder abduction and enhance shoulder joint stability.

[Design and clinical application of a combined shoulder abduction orthosis for post-burn treatment].

Cicatricial contracture is likely to occur at the deep burn wound under the armpits after healing, which results in limitation of shoulder abduction and seriously affects the function of upper limbs of patients. Wearing shoulder abduction orthosis is an effective intervention method for cicatricial contracture under the armpits, but the adjustable shoulder abduction orthosis commonly used clinically at present is limited in the adjustable range, and the customized static orthosis can only maintain the corresponding angle of shoulder abduction. Besides, the above two orthosis can only have the function of unilateral extention, and they are time-consuming for patients with need of bilateral extension. Aiming at the problems mentioned above, a combined shoulder abduction orthosis was designed by the Tongren Hospital of Wuhan University & Wuhan Third Hospital. The low temperature thermoplastic sheet was cut, shaped, and assembled according to the patient's measurement data of abdomen, upper arm, and lumbar to prepare the combined shoulder abduction orthosis. This abduction orthosis can not only extend the cicatrix contracture under the armpits progressively and extensively, so as to effectively prevent the cicatricial contracture under the armpits, but also can select unilateral or bilateral extension based on the contracture limits for shoulder abduction, thus saving time for both medical workers and patients in relevant treatment.

The extent of brachial plexus injury: an important factor in spinal accessory nerve to suprascapular nerve transfer outcomes.

Objective: The purpose of this study was to assess the association between extent of brachial plexus injury and shoulder abduction/external rotation outcomes after spinal accessory nerve (SAN) to suprascapular nerve (SSN) transfer.Methods: A systematic review of the literature was conducted according to PRISMA guidelines. Inclusion criteria were studies reporting outcomes on patients undergoing SAN to SSN nerve transfer. Patients were excluded for the following reasons: age under 18, nerve transfer for reanimation of the shoulder other than SAN to SSN, and less than 12 months of follow-up postoperatively. Pooled analysis was performed, and primary outcomes were Medical Research Council (MRC) score and range of motion (ROM) for shoulder abduction and external rotation. Univariate logistic regression analysis was used to assess the association between extent of brachial plexus injury and shoulder abduction/external rotation outcomes after SAN to SSN transfer. A multivariate logistic regression analysis model including age, injury to surgery interval, and extent of injury as factors was also created.Results: Univariate logistic regression analysis showed greater extent of injury to be a predictor of poorer shoulder abduction outcomes (OR: 0.502; 95% CI: 0.260-0.971, p = 0.040). Multivariate logistic regression analysis confirmed this association (OR: 0.55; 95% CI: 0.236-0.877, p = 0.019). Extent of injury was not significantly associated with external rotation outcomes on univariate analysis (OR: 0.435; 95% CI: 0.095-1.995, p = 0.284) or multivariate analysis (OR: 0.445; 95% CI: 0.097-2.046, p = 0.298). Age and injury to surgery interval were not significantly associated with postoperative outcomes.Conclusions: More extensive brachial plexus injuries are associated with inferior outcomes after SAN to SSN transfer. A potential explanation for this finding includes lost contribution of muscles from the shoulder girdle that receive innervation from outside of the upper brachial plexus. The relationship between extent of injury and postoperative outcomes is important to recognize when determining and discussing operative intervention with patients.

Teres major transfer to restore external rotation of shoulder in Erb palsy patients.

BACKGROUND: The lack of external rotation and shoulder abduction as sequelae of obstetric brachial plexus palsy requires a release of the subscapularis muscle associated with tendon transfer of the internal rotator of the shoulder. The aim of this study was to present the results of a teres major transfer to the infraspinatus tendon. METHODS: This study included 20 patients (9 boys and 11 girls) with a mean age of 3 years 8 months (range, 1.5-14 years). The average follow-up time was 42 months (range, 12-48 months) to determine whether external rotation weakness and internal rotation contracture sequelae were managed by anterior release of the subscapularis and teres major tendon transfer to the infraspinatus tendon. RESULTS: We found marked improvement in shoulder abduction from 67° before surgery to 158° after surgery. We also found marked improvements in active external rotation from 8° before surgery to 85° after surgery and in passive external rotation from 0° preoperatively to 72° postoperatively. Two cases showed a loss of the last degrees of internal rotation, but this improved after physiotherapy. CONCLUSIONS: Anterior release of the subscapularis tendon with a teres major transfer to the infraspinatus tendon significantly improves shoulder function in Erb palsy patients with internal rotation contracture.

Combined Radial to Axillary and Spinal Accessory Nerve (SAN) to Suprascapular Nerve (SSN) Transfers May Confer Superior Shoulder Abduction Compared with Single SA to SSN Transfer.

BACKGROUND: The restoration of shoulder function after brachial plexus injury is a high priority. Shoulder abduction and stabilization can be achieved by nerve transfer procedures including spinal accessory nerve (SAN) to suprascapular nerve (SSN) and radial to axillary nerve transfer. The objective of this study is to compare functional outcomes after SAN to SSN transfer versus the combined radial to axillary and SA to SSN transfer. METHODS: This retrospective chart review included 14 consecutive patients with brachial plexus injury who underwent SAN to SSN transfer, 4 of whom had both SA to SSN and radial to axillary nerve transfer. RESULTS: SAN to SSN transfer achieved successful shoulder abduction (≥M3) in 64.3% of this cohort (9/14). During the long-term follow-up, patients achieved an average increase of 67.5° in shoulder abduction. There was no association between motor recovery and time from injury to surgery, age, body mass index (BMI), sex, or smoking status. The 4 patients who had SAN to SSN combined with radial to axillary nerve transfer demonstrated a statistically significant increase in the range of abduction (median, 90° vs. 42.5°, respectively; P = 0.022) compared with those who had SAN to SSN transfer alone; however, the difference in Medical Research Council (MRC) grades (MRC > M3) did not reach statistical significance (P = 0.07). CONCLUSIONS: Patients with brachial plexus injury and an intact C7 root could benefit from radial to axillary transfer in addition to SAN to SSN transfer. There was no association between recovery of shoulder abduction and time interval from injury to surgery, age, sex, smoking, and BMI.