Axillary Nerve Reconstruction in 176 Posttraumatic Plexopathy Patients:

Neurotization of the axillary nerve using a motor branch of the triceps brachii: Outcomes after a 3-to-15-year follow-up

PURPOSE

Axillary nerve neurotization using a motor branch of the triceps brachii has become a therapeutic option in the management of deltoid paralysis. The purpose of this study was to report the medium to long-term outcomes of this procedure.

MATERIAL AND METHODS

Twenty patients with a median age of 31 years (interquartile range - IQR, 29-53) were included in a single-operator retrospective study. A clinical evaluation was conducted, including the assessment of deltoid muscle strength using the British Medical Research Council grading system and a dynamometer with comparisons made between preoperative and postoperative outcomes.

RESULTS

The median follow-up period was 6 years (IQR, 5-11). At last follow-up, the median active abduction was 160° (IQR 60-160), and 85% of patients recovered at least M3 abduction force. No donor site deficits were identified.

DISCUSSION

The medium to long-term outcomes of the neurotization of a triceps brachii motor branch on the axillary nerve are comparable to the short-term outcomes.

LEVEL OF EVIDENCE

IV.

Peripheral cranio-spinal nerve communication for trapezius muscle control using axonal profiling through immunostaining

Accessory nerve (CNXI) has been known to be the primary conduit for motor control of the trapezius, while the supplementary cervical nerves (C3 and C4) are responsible for processing sensory information from muscle. However, the lack of substantial direct evidence has led to these conclusions being regarded as mere speculation. This study used immunostaining (using antibodies against neurofilament 200 for all axons, choline acetyltransferase for cholinergic axons, tyrosine hydroxylase for sympathetic axons, and alpha 3 sodium potassium ATPase for proprioceptive afferent axons) of human samples to verify the functional contributions of nerves. Study highlights the pivotal role of C3 and C4 in regulating precise movements of trapezius, contributing to motor control, proprioceptive feedback, and sympathetic modulation. CNXI is composed primarily of somatic efferent fibers, with significant numbers of sympathetic or sensory fibers. Furthermore, C3-4 have both cholinergic and non-cholinergic axons, suggesting their involvement in proprioceptive feedback and somatic efferent functions. Although less common, mechanosensors such as nociceptive sensor and sympathetic fibers are also supplied by these cervical nerves. The study demonstrated that these nerves contain motor fibers and significant proprioceptive and sympathetic axons, challenging the long-held notion that CNXI are motor and upper spinal nerves are sensory.

Management of "Long" Nerve Gaps

Long-gap nerve injuries offer unique physiological and logistical treatment challenges to the reconstructive surgeon. Options include nerve autograft, processed nerve allograft, nerve transfers, and tendon transfers. This review provides an evidence-framed discussion regarding the pros and cons of these diverse approaches.

Nerve Allografts: Current Utility and Future Directions

Processed nerve allograft is a widely accepted tool for reconstructing peripheral nerve defects. Repair parameters that need to be considered include gap length, nerve diameter, nerve type (motor, sensory, or mixed), and the soft tissue envelope. Although the use of processed nerve allograft must be considered based on each unique clinical scenario, a rough algorithm can be formed based on the available animal and clinical literature. This article critically reviews the current surgical algorithm, defines the role of processed nerve allograft compared with nerve autograft, and discusses how this role may change in the future.

Nerve Transfers for Brachial Plexus Reconstruction in Patients over 60 Years

Negative expectations regarding nerve reconstruction in the elderly prevail in the literature, but little is known about the effectiveness of nerve transfers in patients with brachial plexus injuries aged over 60 years. We present a series of five patients (1 female, 4 male) aged between 60 and 81 years (median 62.0 years) who underwent nerve reconstruction using multiple nerve transfers in brachial plexopathies. The etiology of brachial plexus injury was trauma (n = 2), or iatrogenic, secondary to spinal surgical laminectomy, tumor excision and radiation for breast cancer (n = 3). All but one patient underwent a one-stage reconstruction including neurolysis and extra-anatomical nerve transfer alone (n = 2) or combined with anatomical reconstruction by sural nerve grafts (n = 2). One patient underwent a two-stage reconstruction, which involved a first stage anatomical brachial plexus reconstruction followed by a second stage nerve transfer. Neurotizations were performed as double (n = 3), triple (n = 1) or quadruple (n = 1) nerve or fascicular transfers. Overall, at least one year postoperatively, successful results, characterized by a muscle strength of M3 or more, were restored in all cases, two patients even achieving M4 grading in the elbow flexion. This patient series challenges the widely held dogma that brachial plexus reconstruction in older patients will produce poor outcomes. Distal nerve transfers are advantageous as they shorten the reinnervation distance. Healthy, more elderly patients should be judiciously offered the whole spectrum of reconstructive methods and postoperative rehabilitation concepts to regain useful arm and hand function and thus preserve independence after a traumatic or nontraumatic brachial plexus injury.

Elevated Body Mass Index Negatively Impacts Recovery of Shoulder Abduction Strength in Triceps Motor Branch to Axillary Nerve Transfers

BACKGROUND

The purpose of this work was to evaluate the clinical outcomes of triceps motor branch to axillary nerve transfers and to identify prognostic factors which may influence these outcomes.

METHODS

A retrospective cohort included all patients who underwent a triceps motor branch to axillary nerve transfer (2010-2019) with at least 12 months of follow-up. The primary outcome measure was shoulder abduction strength assessed with British Medical Research Council (MRC) grade.

RESULTS

Ten patients were included with a mean follow-up of 19.1 (SD 5.9) months. Compared with preoperative MRC shoulder abduction strength (0.2 SD 0.4), patients significantly improved postoperatively (2.8 SD 1.6; P = .005). Increased body mass index (BMI) was significantly associated with worse postoperative MRC (P = .014).

CONCLUSION

Triceps motor branch to axillary nerve transfer is a beneficial procedure for restoring shoulder function in patients presenting with either isolated axillary nerve or brachial plexus pathology. Patients with elevated BMI may not have as robust strength recovery and should be counseled carefully regarding prognosis.

A novel instrumented shoulder functional test using wearable sensors in patients with brachial plexus injury

BACKGROUND

Because nerve injury of muscles around the shoulder can be easily disguised by "trick movements" of the trunk, shoulder dysfunction following brachial plexus injury is difficult to quantify with conventional clinical tools. Thus, to evaluate brachial plexus injury and quantify its biomechanical consequences, we used inertial measurement units, which offer the sensitivity required to measure the trunk's subtle movements.

METHODS

We calculated 6 kinematic scores using inertial measurement units placed on the upper arms and the trunk during 9 functional tasks. We used both statistical and machine learning techniques to compare the bilateral asymmetry of the kinematic scores of 15 affected and 15 able-bodied individuals (controls).

RESULTS

Asymmetry indexes from several kinematic scores of the upper arm and trunk showed a significant difference (P < .05) between the affected and control groups. A bagged ensemble of decision trees trained with trunk and upper arm kinematic scores correctly classified all controls. All but 2 patients were also correctly classified. Upper arm scores showed correlation coefficients ranging from 0.55-0.76 with conventional clinical scores.

CONCLUSIONS

The proposed wearable technology is a sensitive and reliable tool for objective outcome evaluation of brachial plexus injury and its biomechanical consequences. It may be useful in clinical research and practice, especially in large cohorts with multiple follow-ups.

Prevention and Treatment of Nerve Injuries in Shoulder Arthroplasty

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Nerve injuries during shoulder arthroplasty have traditionally been considered rare events, but recent electrodiagnostic studies have shown that intraoperative nerve trauma is relatively common.

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The brachial plexus and axillary and suprascapular nerves are the most commonly injured neurologic structures, with the radial and musculocutaneous nerves being less common sites of injury.

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Specific measures taken during the surgical approach, component implantation, and revision surgery may help to prevent direct nerve injury. Intraoperative positioning maneuvers and arm lengthening warrant consideration to minimize indirect injuries.

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Suspected nerve injuries should be investigated with electromyography preferably at 6 weeks and no later than 3 months postoperatively, allowing for primary reconstruction within 3 to 6 months of injury when indicated. Primary reconstructive options include neurolysis, direct nerve repair, nerve grafting, and nerve transfers.

➤

Secondary reconstruction is preferred for injuries presenting >12 months after surgery. Secondary reconstructive options with favorable outcomes include tendon transfers and free functioning muscle transfers.

Radial to Axillary Nerve Transfer Outcomes in Shoulder Abduction: A Systematic Review

Background

Brachial plexus and axillary nerve injuries often result in paralysis of the deltoid muscle. This can be functionally debilitating for patients and have a negative impact on their activities of daily living. In these settings, transferring the branch of the radial nerve innervating the triceps to the axillary nerve is a viable treatment option. Additional nerve transfers may be warranted. This study sought to determine the efficacy of nerve transfer procedures in the setting of brachial plexus and axillary nerve injuries and factors affecting clinical outcomes.

Methods

The U.S. National Library of Medicine's website "PubMed" was queried for "radial to axillary nerve transfer" and "brachial plexus nerve transfer." An initial review by two authors was performed to identify relevant articles followed by a third author validation utilizing inclusion and exclusion criteria. Individual patient outcomes were recorded and pooled for final analysis.

Results

Of the 80 patients, 66 (82.5%) had clinical improvement after surgical nerve transfer procedures. Significant difference in clinical improvement following nerve transfer procedures was correlated with patient age, mechanism of injury, brachial plexus vs isolated axillary nerve injuries, multiple nerve transfers vs single nerve transfers, and surgery within the first 7 months of injury. The branch of the radial nerve supplying the triceps long head showed improved clinical results compared with the branch of the radial nerve supplying the triceps medial head and anconeus.

Conclusion

Nerve transfers have been shown to be effective in restoring shoulder abduction in both isolated axillary nerve injuries and brachial plexus injuries.

Analysis of human acellular nerve allograft combined with contralateral C7 nerve root transfer for restoration of shoulder abduction and elbow flexion in brachial plexus injury: a mean 4-year follow-up

OBJECTIVE

Human acellular nerve allograft applications have increased in clinical practice, but no studies have quantified their influence on reconstruction outcomes for high-level, greater, and mixed nerves, especially the brachial plexus. The authors investigated the functional outcomes of human acellular nerve allograft reconstruction for nerve gaps in patients with brachial plexus injury (BPI) undergoing contralateral C7 (CC7) nerve root transfer to innervate the upper trunk, and they determined the independent predictors of recovery in shoulder abduction and elbow flexion.

METHODS

Forty-five patients with partial or total BPI were eligible for this retrospective study after CC7 nerve root transfer to the upper trunk using human acellular nerve allografts. Deltoid and biceps muscle strength, degree of shoulder abduction and elbow flexion, Semmes-Weinstein monofilament test, and static two-point discrimination (S2PD) were examined according to the modified British Medical Research Council (mBMRC) scoring system, and disabilities of the arm, shoulder, and hand (DASH) were scored to establish the function of the affected upper limb. Meaningful recovery was defined as grades of M3-M5 or S3-S4 based on the scoring system. Subgroup analysis and univariate and multivariate logistic regression analyses were conducted to identify predictors of human acellular nerve allograft reconstruction.

RESULTS

The mean follow-up duration and the mean human acellular nerve allograft length were 48.1 ± 10.1 months and 30.9 ± 5.9 mm, respectively. Deltoid and biceps muscle strength was grade M4 or M3 in 71.1% and 60.0% of patients. Patients in the following groups achieved a higher rate of meaningful recovery in deltoid and biceps strength, as well as lower DASH scores (p < 0.01): age < 20 years and age 20-29 years; allograft lengths ≤ 30 mm; and patients in whom the interval between injury and surgery was < 90 days. The meaningful sensory recovery rate was approximately 70% in the Semmes-Weinstein monofilament test and S2PD. According to univariate and multivariate logistic regression analyses, age, interval between injury and surgery, and allograft length significantly influenced functional outcomes.

CONCLUSIONS

Human acellular nerve allografts offered safe reconstruction for 20- to 50-mm nerve gaps in procedures for CC7 nerve root transfer to repair the upper trunk after BPI. The group in which allograft lengths were ≤ 30 mm achieved better functional outcome than others, and the recommended length of allograft in this procedure was less than 30 mm. Age, interval between injury and surgery, and allograft length were independent predictors of functional outcomes after human acellular nerve allograft reconstruction.

Brachial plexus injury after shoulder dislocation: a literature review

Brachial plexus injuries are among the rarest but at the same time the most severe complications of shoulder dislocation. The symptoms range from transient weakening or tingling sensation of the upper limb to total permanent paralysis of the limb associated with chronic pain and disability. Conflicting opinions exist as to whether these injuries should be treated operatively and if so when surgery should be performed. In this review, available literature dedicated to neurological complications of shoulder dislocation has been analysed and management algorithm has been proposed. Neurological complications were found in 5.4-55% of all dislocations, with the two most commonly affected patient groups being elderly women sustaining dislocation as a result of a simple fall and young men after high-energy injuries, often multitrauma victims. Infraclavicular part of the brachial plexus was most often affected. Neurapraxia or axonotmesis predominated, and complete nerve disruption was observed in less than 3% of the patients. Shoulder dislocation caused injury to multiple nerves more often than mononeuropathies. The axillary nerve was most commonly affected, both as a single nerve and in combination with other nerves. Older patient age, higher energy of the initial trauma and longer period from dislocation to its reduction have been postulated as risk factors. Brachial plexus injury resolved spontaneously in the majority of the patients. Operative treatment was required in 13-18% of the patients in different studies. Patients with suspected neurological complications require systematic control. Surgery should be performed within 3-6 months from the injury when no signs of recovery are present.

Nerve Transfers-A Paradigm Shift in the Reconstructive Ladder

In this review, we present the current role of nerve transfers in the management of nerve injuries. The outcome of a literature review comparing the results of nerve graft versus nerve transfer and the experience of select surgical societies' members regarding experience and adoption of nerve transfer are reported. Nerve transfer publications have increased more than nerve graft or repair articles. The surgeon survey revealed an increase in nerve transfers and that more motor nerve transfers have been adopted into practice compared to sensory nerve transfers. The meta-analyses and systematic reviews of motor nerve transfers for shoulder and elbow function presented variable outcomes related to donor nerve selection. Comprehensive patient assessment is essential to evaluate the immediate functional needs and consider future reconstruction that may be necessary. Optimal outcome following nerve injury may involve a combination of different surgical options and more than one type of reconstruction. Nerve transfer is a logical extension of the paradigm shift from nerve repair and nerve graft and offers a new rung on the reconstruction ladder.

Traumatic Brachial Plexopathy in Athletes: Current Concepts for Diagnosis and Management of Stingers

Traumatic upper trunk brachial plexopathy, also known as a stinger or burner, is the most common upper extremity neurologic injury among athletes and most commonly involves the upper trunk. Recent studies have shown the incidence of both acute and recurrent injuries to be higher in patients with certain anatomic changes in the cervical spine. In addition, despite modern awareness, tackling techniques, and protective equipment, some think the incidence to be slowly on the rise in contact athletes. The severity of neurologic injury varies widely but usually does not result in significant loss of playing time or permanent neurologic deficits if appropriate management is undertaken. Timely diagnosis allows implementation of means to minimize the risk of recurrent injury. It is important for treating physicians to understand the pathogenesis, evaluation, and acute and long-term management of stingers to improve recovery and minimize chronic sequela.

Comparison between direct repair and human acellular nerve allografting during contralateral C7 transfer to the upper trunk for restoration of shoulder abduction and elbow flexion

Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct repair can only be performed in some selected cases, and partial procedures still require autografts, which are the gold standard for repairing neurologic defects. As symptoms often occur after autografting, human acellular nerve allografts have been used to avoid concomitant symptoms. This study investigated the quality of shoulder abduction and elbow flexion following direct repair and acellular allografting to evaluate issues requiring attention for brachial plexus injury repair. Fifty-one brachial plexus injury patients in the surgical database were eligible for this retrospective study. Patients were divided into two groups according to different surgical methods. Direct repair was performed in 27 patients, while acellular nerve allografts were used to bridge the gap between the contralateral C7 nerve root and upper trunk in 24 patients. The length of the harvested contralateral C7 nerve root was measured intraoperatively. Deltoid and biceps muscle strength, and degrees of shoulder abduction and elbow flexion were examined according to the British Medical Research Council scoring system; meaningful recovery was defined as M3–M5. Lengths of anterior and posterior divisions of the contralateral C7 in the direct repair group were 7.64 ± 0.69 mm and 7.55 ± 0.69 mm, respectively, and in the acellular nerve allografts group were 6.46 ± 0.58 mm and 6.43 ± 0.59 mm, respectively. After a minimum of 4-year follow-up, meaningful recoveries of deltoid and biceps muscles in the direct repair group were 88.89% and 85.19%, respectively, while they were 70.83% and 66.67% in the acellular nerve allografts group. Time to C5/C6 reinnervation was shorter in the direct repair group compared with the acellular nerve allografts group. Direct repair facilitated the restoration of shoulder abduction and elbow flexion. Thus, if direct coaptation is not possible, use of acellular nerve allografts is a suitable option. This study was approved by the Medical Ethical Committee of the First Affiliated Hospital of Sun Yat-sen University, China (Application ID: [2017] 290) on November 14, 2017.

Nerve Transfers-A Paradigm Shift in the Reconstructive Ladder

Supplemental Digital Content is available in the text.

In this review, we present the current role of nerve transfers in the management of nerve injuries. The outcome of a literature review comparing the results of nerve graft versus nerve transfer and the experience of select surgical societies’ members regarding experience and adoption of nerve transfer are reported. Nerve transfer publications have increased more than nerve graft or repair articles. The surgeon survey revealed an increase in nerve transfers and that more motor nerve transfers have been adopted into practice compared to sensory nerve transfers. The meta-analyses and systematic reviews of motor nerve transfers for shoulder and elbow function presented variable outcomes related to donor nerve selection. Comprehensive patient assessment is essential to evaluate the immediate functional needs and consider future reconstruction that may be necessary. Optimal outcome following nerve injury may involve a combination of different surgical options and more than one type of reconstruction. Nerve transfer is a logical extension of the paradigm shift from nerve repair and nerve graft and offers a new rung on the reconstruction ladder.

Comparative study of single and dual nerve transfers for repairing shoulder abduction

OBJECTIVE

The purpose of this study was to compare the effects of single and dual nerve transfer for the repair of shoulder abduction in patients with upper or upper and middle trunk root avulsion.

METHODS

We carried out a retrospective analysis of 20 patients with C5-C6 or C5-C7 root avulsion treated by nerve transfer in our hospital. The patients were divided into two groups according to the different operation methods. In group A, ten patients had transferred the spinal accessory nerve to the suprascapular nerve. Ten patients in group B underwent dual nerve transfer to reconstruct shoulder abduction, including the spinal accessory nerve transfer to the suprascapular nerve and two intercostal nerves or the long head of triceps nerve branch transfer to the anterior branch of the axillary nerve. There was no difference in age, preoperative interval, follow-up time, and injury type between the two groups. We used shoulder abduction strength, shoulder abduction angle, and Samardzic's shoulder joint evaluation standard as the postoperative evaluation index. Shoulder abductor muscle strength equals or above M3 was considered to be an effective recovery.

RESULTS

Of the 20 cases, 15 obtained equals or more M3 of shoulder abduction strength, and the overall effective rate was 75%. The effective rate of shoulder abduction power in group A was 60% (6/10) while group B was 90% (9/10); however, the difference was not statistically significant (p > 0.05). The average shoulder abduction angle was 55° (SD = 19.29) in group A and 77° (SD = 20.44) in group B; the angle was significantly better in group B than that in group A (p < 0.05). Based on Samardzic's standard, the excellent and good rate of group A was 90% and in group B was 50%. The difference was statistically significant (p < 0.05).

CONCLUSION

For patients with nerve root avulsion of C5-C6 or C5-C7, repairing suprascapular nerve and axillary nerve at the same time is more effective than repairing suprascapular nerve alone in terms of shoulder abduction angle and excellent rate of functional recovery of the shoulder joint. Therefore, we recommend the repair of the suprascapular nerve and the axillary nerve simultaneously if conditions permit.

Timing of surgery in traumatic brachial plexus injury: a systematic review

OBJECTIVE

Ideal timeframes for operating on traumatic stretch and blunt brachial plexus injuries remain a topic of debate. Whereas on the one hand spontaneous recovery might occur, on the other hand, long delays are believed to result in poorer functional outcomes. The goal of this review is to assess the optimal timeframe for surgical intervention for traumatic brachial plexus injuries.

METHODS

A systematic search was performed in January 2017 in PubMed and Embase databases according to the PRISMA guidelines. Search terms related to "brachial plexus injury" and "timing" were used. Obstetric plexus palsies were excluded. Qualitative synthesis was performed on all studies. Timing of operation and motor outcome were collected from individual patient data. Patients were categorized into 5 delay groups (0-3, 3-6, 6-9, 9-12, and > 12 months). Median delays were calculated for Medical Research Council (MRC) muscle grade ≥ 3 and ≥ 4 recoveries.

RESULTS

Forty-three studies were included after full-text screening. Most articles showed significantly better motor outcome with delays to surgery less than 6 months, with some studies specifying even shorter delays. Pain and quality of life scores were also significantly better with shorter delays. Nerve reconstructions performed after long time intervals, even more than 12 months, can still be useful. All papers reporting individual-level patient data described a combined total of 569 patients; 65.5% of all patients underwent operations within 6 months and 27.4% within 3 months. The highest percentage of ≥ MRC grade 3 (89.7%) was observed in the group operated on within 3 months. These percentages decreased with longer delays, with only 35.7% ≥ MRC grade 3 with delays > 12 months. A median delay of 4 months (IQR 3-6 months) was observed for a recovery of ≥ MRC grade 3, compared with a median delay of 7 months (IQR 5-11 months) for ≤ MRC grade 3 recovery.

CONCLUSIONS

The results of this systematic review show that in stretch and blunt injury of the brachial plexus, the optimal time to surgery is shorter than 6 months. In general, a 3-month delay appears to be appropriate because while recovery is better in those operated on earlier, this must be considered given the potential for spontaneous recovery.

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.

Outcomes of shoulder abduction after nerve surgery in patients over 50 years following traumatic brachial plexus injury

PURPOSE

There is controversy regarding the effectiveness of brachial plexus reconstruction in older patients, as outcomes are thought to be poor. The aim of this study is to determine the outcomes of shoulder abduction obtained after nerve reconstruction in patients over the age of 50 years and factors related to success.

METHODS

Forty patients over the age of 50 years underwent nerve surgery to improve shoulder function after a traumatic brachial plexus injury. Patients were evaluated pre- and postoperatively for shoulder abduction strength and range of motion (ROM); Disability of the Arm, Shoulder and Hand (DASH) scores; pain; age bracket; gender; body mass index (BMI); delay from injury to operation; concomitant trauma; severity of trauma; and type of reconstruction.

RESULTS

The average age was 58.2 years (range 50-77 years) with an average follow-up of 18.8 months. The average modified British Medical Research Council (BMRC) shoulder abduction grade improved significantly from 0.23 to 2.03 (p < 0.005). Fourteen patients achieved functional shoulder abduction of ≥ M3 postoperatively. There was no correlation between age or age range stratification and BMRC grade or those obtaining useful shoulder abduction ≥ M3. Active shoulder abduction improved significantly from 18.25° to 40.64°, with no difference on the basis of age or age stratification. There were improved modified BMRC grades with nerve transfers versus nerve grafts. Less patients achieved ≥ M3 function if surgery was delayed > 6 months. The mean DASH score decreased from 45.3 to 40.7 postoperatively, and the average pain score decreased from 3.7 to 3.0. Patients with a higher postoperative BMRC grade for shoulder abduction had improved postoperative DASH scores and VAS for pain (p = 0.011 and 0.005, respectively).

CONCLUSION

Brachial plexus nerve reconstruction for shoulder abduction in patients over the age of 50 years can yield useful BMRC scores and ROM, and age should not be used to exclude nerve reconstruction in these patients.

Axillary nerve neurotization by a triceps motor branch: comparison between axillary and posterior arm approaches

Objectives

This study is aimed at comparing the functional outcome of axillary nerve neurotization by a triceps motor branch through the axillary approach and posterior arm approach.

Methods

The study included 27 patients with post-traumatic brachial plexus injury treated with axillary nerve neurotization by a triceps motor branch for functional recovery of shoulder abduction and external rotation. The patients were retrospectively evaluated and two groups were identified, one with 13 patients undergoing axillary nerve neurotization by an axillary approach and the second with 14 patients using the posterior arm approach. Patients underwent assessment of muscle strength using the scale recommended by the British Medical Research Council, preoperatively and 18 months postoperatively, with useful function recovery considered as grade M3 or greater.

Results

In the axillary approach group, 76.9% of patients achieved useful abduction function recovery and 69.2% achieved useful external rotation function recovery. In the group with posterior arm approach, 71.4% of patients achieved useful abduction function recovery and 50% achieved useful external rotation function recovery. The difference between the two groups was not statistically significant (p = 1.000 for the British Medical Research Council abduction scale and p = 0.440 for external rotation).

Conclusion

According to the British Medical Research Council grading, axillary nerve neurotization with a triceps motor branch using axillary approach or posterior arm approach shows no statistical differences.

Radial to Axillary Nerve Transfers: A Combined Case Series

PURPOSE

Loss of active shoulder abduction after brachial plexus or isolated axillary nerve injury is associated with a severe functional deficit. The purpose of this 2-center study was to retrospectively evaluate restoration of shoulder abduction after transfer of a radial nerve branch to the axillary nerve for patients after brachial plexus or axillary nerve injury.

METHODS

Patients who underwent transfer of a radial nerve branch to the anterior branch of the axillary nerve between 2004 and 2014 were reviewed. A total of 27 patients with an average follow-up of 22 months were included. Outcome measures included pre- and postoperative shoulder abduction and triceps strength and active and passive shoulder range of motion.

RESULTS

Shoulder abduction strength increased after surgery in 89% of patients. Average preoperative shoulder abduction was 12° compared with 114° after surgery. Twenty-two of 27 patients (81.5%) achieved at least M3 strength, with 17 of 27 patients (62.9%) achieving M4 strength. No differences were observed when subgroup analysis was performed for isolated nerve transfer versus multiple nerve transfer, mechanism of injury, injury level, branch of radial nerve transferred, or time from injury to surgery. A negative correlation was found comparing increasing age and both shoulder abduction strength and active shoulder abduction. No patients lost triceps strength after surgery. There were 4 patients who achieved no significant gain in shoulder abduction or deltoid strength and were deemed failures. No postoperative complications occurred.

CONCLUSIONS

Transfer of a branch of the radial nerve to the anterior branch of the axillary nerve was successful in improving shoulder abduction strength and active shoulder motion in the majority of the patients with brachial plexus or isolated axillary nerve injury.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Successful Nerve Transfers for Traumatic Brachial Plexus Palsy in a Septuagenarian: A Case Report

Background: Conventional wisdom and the available literature demonstrate compromised outcomes following nerve reconstruction for traumatic brachial plexus palsy in the elderly. We present a 74-year-old male who was reconstructed with multiple nerve transfers for brachial plexus palsy after a ski accident. Methods: Triceps to axillary nerve transfer, spinal accessory to suprascapular nerve transfer, and ulnar to musculocutaneous nerve transfer were performed 16 weeks post injury. Results: At 11 years post-op, the patient could abduct to 65° and forward flex at M4 strength, limited only by painful glenohumeral arthritis. Elbow flexion was M5- at both the biceps and brachialis, and bulk and tone were nearly symmetrical with the opposite side. Eleven-year electrodiagnostic studies demonstrated reinnervation and improved motor unit recruitment all affected muscles. Conclusion: This case questions the widely held dogma that older patients who undergo brachial plexus reconstruction do poorly. Given the short reinnervation distance and optimal donor nerve health, nerve transfers may be an excellent option for healthy older patients with traumatic brachial plexus palsy.

Evaluation of infraspinatus reinnervation and function following spinal accessory nerve to suprascapular nerve transfer in adult traumatic brachial plexus injuries

PURPOSE

Our objective was to determine the prevalence and quality of restored external rotation (ER) in adult brachial plexus injury (BPI) patients who underwent spinal accessory nerve (SAN) to suprascapular nerve (SSN) transfer, and to identify patient and injury factors that may influence results.

METHODS

Fifty-one adult traumatic BPI patients who underwent SAN to SSN transfer between 2000 and 2013, all treated less than 1 year after injury with >1 year follow-up. The primary outcome measured was shoulder ER. The outcomes we utilized included "clinically useful ER" (motion ≥ -35° with ≥MRC 2 strength), modified British Medical Research Council (MRC) grading, and electromyographic (EMG) reinnervation.

RESULTS

EMG evidence of re-innervation was found in 85% of patients. Surgery resulted in improved ER in 41% (21/51) of shoulders at an average of 28 months follow-up. Of these, only 31% (17/51) had clinically useful ER. The average ER active range of motion was 12° from full internal rotation (Range: -60° to 90°) and MRC grade 2.2 (2-4). The only predictor of ER improvement was an isolated upper trunk (C5-C6) injury. Improved ER was clinically evident in 76%, 37% and 26% of upper trunk (UT), C5-C6-C7 and panplexus injuries, respectively (P < 0.03).

CONCLUSIONS

Although 85% had EMG signs of recovery, the SAN to SSN transfer failed to provide useful recovery of ER through reinnervation of the infraspinatus muscle in injuries involving more levels than a C5-C6 root/upper trunk pattern. In patients with greater than C5-6 level injuries alternatives to SAN to SSN transfer should be considered to restore shoulder ER. © 2016 Wiley Periodicals, Inc. Microsurgery 37:365-370, 2017.

Shoulder and Elbow Recovery at 2 and 11 Years Following Brachial Plexus Reconstruction

PURPOSE

To report short-term and long-term outcomes on a single patient cohort observed longitudinally after nerve reconstruction for adult brachial plexus injury.

METHODS

Eleven male patients who underwent plexus reconstruction by the same surgeon at 2 institutions presented for clinical examination 7.5 or more years after surgery (average, 11.4 years; range, 7.5-22 years). Average age at the time of operation was 35 years (range, 17-73 years). Mean delay until surgery was 5 months (range, 2-11 months). Two patients had C5 paralysis, 2 had C5-C6 paralysis, 2 had C5-C7 paralysis, and 5 had complete 5-level injuries. Outcome parameters included active range of motion (ROM) in degrees, a modified British Medical Research Council (mBMRC) scale for muscle strength, and electromyographic motor unit configuration and recruitment pattern. Differences in ROM and mBMRC between 2-year and long-term follow-up were assessed with paired-sample t tests using an alpha value of .05.

RESULTS

Average shoulder abduction and mBMRC at final follow-up were both significantly improved compared with the 2-year follow-up results (P < .05). Average elbow flexion and mBMRC increased significantly between 2 years and final follow-up (P < .05). Electromyographic results for 6 patients at final follow-up showed improved motor unit configuration in 10 of 15 muscles and improved recruitment in 3 of 15 muscles compared with 2-year electromyographic results.

CONCLUSIONS

Patients continued to gain ROM and strength in the shoulder and elbow well after 2 to 3 years after surgery, contrary to previous reports. Although the precise mechanism is unknown, we speculate that a number of factors may be involved, including terminal collateral sprouting, maturation of motor units, improvements in motor unit recruitment, additional muscle fiber hypertrophy, or an as-yet undescribed mechanism. We recommend that patients be encouraged to continue strengthening exercises well after the initial recovery period and that more comparative long-term data be collected to expand on these observations.

Relationship between maximum isometric joint moment and functional task performance in patients with brachial plexus injury: A pilot study

We evaluated whether subjects with brachial plexus injury (BPI) adapted their movements to reduce the mechanical demand on their impaired upper extremity. In 6 subjects with unilateral BPI with C5 and C6 involvement, we measured bilateral maximum isometric shoulder and elbow strength, and computed joint kinematics and net muscle-generated joint moments during 7 unimanual functional tasks. Compared to the unimpaired extremity, maximum strength in shoulder abduction, extension, and external rotation was 60% (p=0.02), 49% (p=0.02), and 75% (p=0.02) lower, respectively, on the impaired side. Significant kinematic and kinetic differences were observed only when reaching to the back of the head. However, because of substantially reduced strength in their impaired upper extremities, subjects used a significantly higher percentage of their maximum strength during several tasks and along several directions of movement. The peak percentage of maximal strength subjects used across tasks was 32% (p=0.03) and 29% (p=0.03) more on their impaired side in shoulder extension and external rotation, respectively. Subjects had less reserve strength available for performing upper extremity tasks and, therefore, may be less adaptive to strength declines due to injury progression and normal aging. Quantitatively measuring maximal strength may help clinicians ensure that patients maintain sufficient upper extremity strength to preserve long-term functional ability.

Nerve transfers and neurotization in peripheral nerve injury, from surgery to rehabilitation

Peripheral nerve injury (PNI) and recent advances in nerve reconstruction (such as neurotization with nerve transfers) have improved outcomes for patients suffering peripheral nerve trauma. The purpose of this paper is to bridge the gap between the electromyographer/clinical neurophysiologist and the peripheral nerve surgeon. Whereas the preceding literature focuses on either the basic science behind nerve injury and reconstruction, or the surgical options and algorithms, this paper demonstrates how electromyography is not just a 'decision tool' when deciding whether to operate but is also essential to all phases of PNI management including surgery and rehabilitation. The recent advances in the reconstruction and rehabilitation of PNI is demonstrated using case examples to assist the electromyographer to understand modern surgical techniques and the unique demands they ask from electrodiagnostic testing.

Axillary Nerve Reconstruction: Anterior-Posterior Exposure With Sural Nerve Cable Graft Pull-Through Technique

Deltoid paralysis after axillary nerve injury results in limitations in shoulder function and stability. In the setting of an isolated axillary nerve injury with no clinical or electromyographic evidence of recovery that is within 6 to 9 months postinjury, the authors' preferred technique to reinnervate the deltoid is to reconstruct the axillary nerve with sural nerve grafting. Intraoperative neuromuscular electrophysiology is critical to determine the continuity of the axillary nerve before proceeding with reconstruction. The majority of the time, both an anterior and posterior incision and dissection of the axillary nerve is required to adequately delineate the zone of injury. This also ensures that both proximally and distally, uninjured axillary nerve is present before graft inset and also facilitates the ability to perform a meticulous microsurgical inset of the nerve graft posteriorly. The nerve graft must be pulled through from posterior to anterior to span the zone of injury and reconstruct the axillary nerve. Careful infraclavicular brachial plexus dissection is necessary to prevent further injury to components of the brachial plexus in the setting of a scarred bed. Patients will require postoperative therapy to prevent limitations in shoulder range of motion secondary to postoperative stiffness. This paper presents a detailed surgical technique for axillary nerve reconstruction by an anterior-posterior approach with a pull-through technique of a sural nerve cable graft.

Triceps motor branch transfer for isolated traumatic pediatric axillary nerve injuries

OBJECT

Transfer of the triceps motor branch has been used for treatment of isolated axillary nerve palsy in the adult population. However, there are no published data on the effectiveness of this procedure in the pediatric population with traumatic injuries. The authors reviewed demographics and outcomes in their series of pediatric patients who underwent this procedure.

METHODS

Six patients ranging in age from 10 to 17 years underwent triceps motor branch transfer for the treatment of isolated axillary nerve injuries between 4 and 8 months after the inciting injury. Deltoid muscle strength was evaluated using the modified British Medical Research Council (MRC) grading system. Shoulder abduction at last follow-up was measured.

RESULTS

The mean duration of follow-up was 38 months. The average postoperative MRC grading of deltoid muscle strength was 3.6 ± 1.3. The median MRC grade was 4. One patient who did not achieve an MRC grade of 3 suffered multiple injuries from high-velocity trauma. Unlike in the adult population, age, body mass index of the patient, and delay from injury to surgery were not significant factors affecting the outcome of the procedure.

CONCLUSIONS

In the pediatric population with traumatic injuries, isolated axillary nerve injury treated with triceps motor branch transfer can result in good outcomes.

Long-nerve grafts and nerve transfers demonstrate comparable outcomes for axillary nerve injuries

PURPOSE

To compare the functional and EMG outcomes of long-nerve grafts to nerve transfers for complete axillary nerve palsy.

METHODS

Over a 10-year period at a single institution, 14 patients with axillary nerve palsy were treated with long-nerve grafts and 24 patients were treated with triceps-to-axillary nerve transfers by the same surgeon (S.W.W.). Data were collected prospectively at regular intervals, beginning before surgery and continuing up to 11 years after surgery. Prior to intervention, all patients demonstrated EMG evidence of complete denervation of the deltoid. Deltoid recovery (Medical Research Council [MRC] grade), shoulder abduction (°), improvement in shoulder abduction (°), and EMG evidence of deltoid reinnervation were compared between cohorts.

RESULTS

There were no significant differences between the long-nerve graft cohort and the nerve transfer cohort with respect to postoperative range of motion, deltoid recovery, improvement in shoulder abduction, or EMG evidence of deltoid reinnervation.

CONCLUSIONS

These data demonstrate that outcomes of long-nerve grafts for axillary nerve palsy are comparable with those of modern nerve transfers and question a widely held belief that long-nerve grafts do poorly. When healthy donor roots or trunks are available, long-nerve grafts should not be overlooked as an effective intervention for the treatment of axillary nerve injuries in adults with brachial plexus injuries.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

End-to-side neurorrhaphy in brachial plexus reconstruction

Object

Although a number of theoretical and experimental studies dealing with end-to-side neurorrhaphy (ETSN) have been published to date, there is still a considerable lack of clinical trials investigating this technique. Here, the authors describe their experience with ETSN in axillary and musculocutaneous nerve reconstruction in patients with brachial plexus palsy.

Methods

From 1999 to 2007, out of 791 reconstructed nerves in 441 patients treated for brachial plexus injury, the authors performed 21 axillary and 2 musculocutaneous nerve sutures onto the median, ulnar, or radial nerves. This technique was only performed in patients whose donor nerves, such as the thoracodorsal and medial pectoral nerves, which the authors generally use for repair of axillary and musculocutaneous nerves, respectively, were not available. In all patients, a perineurial suture was carried out after the creation of a perineurial window.

Results

The overall success rate of the ETSN was 43.5%. Reinnervation of the deltoid muscle with axillary nerve suture was successful in 47.6% of the patients, but reinnervation of the biceps muscle was unsuccessful in the 2 patients undergoing musculocutaneous nerve repair.

Conclusions

The authors conclude that ETSN should be performed in axillary nerve reconstruction but only when commonly used donor nerves are not available.

Isolated latissimus dorsi transfer to restore shoulder external rotation in adults with brachial plexus injury

In adults with brachial plexus injuries, lack of active external rotation at the shoulder is one of the most common residual deficits, significantly compromising upper limb function. There is a paucity of evidence to address this complex issue. We present our experience of isolated latissimus dorsi (LD) muscle transfer to achieve active external rotation. This is a retrospective review of 24 adult post-traumatic plexopathy patients who underwent isolated latissimus dorsi muscle transfer to restore external rotation of the shoulder between 1997 and 2010. All patients were male with a mean age of 34 years (21 to 57). All the patients underwent isolated LD muscle transfer using a standard technique to correct external rotational deficit. Outcome was assessed for improvement in active external rotation, arc of movement, muscle strength and return to work. The mean improvement in active external rotation from neutral was 24° (10° to 50°). The mean increase in arc of rotation was 52° (38° to 55°). Mean power of the external rotators was 3.5 Medical Research Council (MRC) grades (2 to 5). A total of 21 patients (88%) were back in work by the time of last follow up. Of these, 13 had returned to their pre-injury occupation. Isolated latissimus dorsi muscle transfer provides a simple and reliable method of restoring useful active external rotation in adults with brachial plexus injuries with internal rotational deformity.

Progressive nerve territory overgrowth after subtotal resection of lipomatosis of the median nerve in the palm and wrist: a case, a review and a paradigm

BACKGROUND

Lipomatosis of the nerve (LN) is a rare disorder characterized by the massive enlargement of peripheral nerves, frequently accompanied by generalized fibroadipose proliferation and skeletal overgrowth. The treatment of this disorder remains controversial, in part because of the rarity and the variability of presentation. Some authors have advocated total resection of this benign lesion including the functioning nerve, while others recommend symptomatic decompression alone.

METHODS

We have been routinely following a 10-year-old boy for lipomatosis of the median nerve at the wrist noted shortly after birth. He underwent median nerve resection accompanied by sural nerve grafting at another institute. We review the literature on LN and the efficacy of nerve grafting.

RESULTS

Clinically, he made a good recovery, with mild loss of thenar function and relatively preserved sensation. Serial magnetic resonance imaging over 5 years has revealed progression of the LN at both coaptation sites, fibrofatty proliferation within the nerve grafts as well as distal digital nerves, and enlargement of a fibrous scar at the coaptation sites. This has never been reported in the 9 decades of study of this disease.

CONCLUSION

We present the first medium-term follow-up of a patient who underwent nerve sacrifice to attempt to cure the LN alongside a historical review of treatment. We believe that macroscopic gross total resection (i.e., microscopic subtotal resection) is insufficient in stopping the potential progression of this hamartomatous lesion because of the persistent effect of trophic factors.

Shoulder abduction and external rotation restoration with nerve transfer

INTRODUCTION

In upper brachial plexus palsy patients, loss of shoulder function and elbow flexion is obvious as the result of paralysed muscles innervated by the suprascapular, axillary and musculocutaneus nerve. Shoulder stabilisation, restoration of abduction and external rotation are important as more distal functions will be affected by the shoulder situation.

PATIENTS AND METHODS

Between 2005 and 2011, eleven patients with upper type brachial plexus palsy were operated on with triceps nerve branch transfer to anterior axillary nerve branch and spinal accessory nerve transfer to the suprascapular nerve for shoulder abduction and external rotation restoration. Nine patients met the inclusion criteria for the study. All patients were men with ages ranged from 21 to 35 years (average, 27.4 years). The interval between injury and surgery ranged from 4 to 11 months (average, 7.2 months). Atrophy of the supraspinatus, infraspinatus and deltoid muscle and subluxation at the glenohumeral joint was obvious in all patients preoperatively. During the pre-op examination all patients had at least muscle grading 4 on the triceps muscle.

RESULTS

The mean post-operative value of shoulder abduction was 112.2° (range: 60-170°) while preoperatively none of the patients was able for abduction (p<0.001). The mean post-operative value of shoulder external rotation was 66° (range: 35-110°) while preoperatively none of them was able for external rotation (p<0.001). Postoperative values of shoulder abduction were significantly better that those of external rotation (p=0.0004). The postoperative average muscle grading for shoulder abduction according the MRC scale was 3.6±0.5 and for the shoulder external rotation was 3.2±0.4.

CONCLUSIONS

Combined nerve transfer by using the spinal accessory nerve for suprascapular nerve neurotisation and one of the triceps nerve branches for axillary nerve and teres minor branch neurotisation is an excellent choice for shoulder abduction and external rotation restoration.

Biomechanical contributions of posterior deltoid and teres minor in the context of axillary nerve injury: a computational study

PURPOSE

To determine whether transfer to only the anterior branch of the axillary nerve will restore useful function after axillary nerve injury with persistent posterior deltoid and teres minor paralysis.

METHODS

We used a computational musculoskeletal model of the upper limb to determine the relative contributions of posterior deltoid and teres minor to maximum joint moment generated during a simulated static strength assessment and to joint moments during 3 submaximal shoulder movements. Movement simulations were performed with and without simulated posterior deltoid and teres minor paralysis to identify muscles that may compensate for their paralysis.

RESULTS

In the unimpaired limb model, teres minor and posterior deltoid accounted for 16% and 14% of the total isometric shoulder extension and external rotation joint moments, respectively. During the 3 movement simulations, posterior deltoid produced as much as 20% of the mean shoulder extension moment, whereas teres minor accounted for less than 5% of the mean joint moment in all directions of movement. When we paralyzed posterior deltoid and teres minor, the mean extension moments generated by the supraspinatus, long head of triceps, latissimus dorsi, and middle deltoid increased to compensate. Compensatory muscles were not fully activated during movement simulations when posterior deltoid and teres minor were paralyzed.

CONCLUSIONS

Reconstruction of the anterior branch of the axillary nerve only is an appropriate technique for restoring shoulder abduction strength after isolated axillary nerve injury. When shoulder extension strength is compromised by extensive neuromuscular shoulder injury, reconstruction of both the anterior and posterior branches of the axillary nerve should be considered.

CLINICAL RELEVANCE

By quantifying the biomechanical role of muscles during submaximal movement, in addition to quantifying muscle contributions to maximal shoulder strength, we can inform preoperative planning and permit more accurate predictions of functional outcomes.

Factors affecting outcome of triceps motor branch transfer for isolated axillary nerve injury

PURPOSE

Triceps motor branch transfer has been used in upper brachial plexus injury and is potentially effective for isolated axillary nerve injury in lieu of sural nerve grafting. We evaluated the functional outcome of this procedure and determined factors that influenced the outcome.

METHODS

A retrospective chart review was performed of 21 patients (mean age, 38 y; range, 16-79 y) who underwent triceps motor branch transfer for the treatment of isolated axillary nerve injury. Deltoid muscle strength was evaluated using the modified British Medical Research Council grading at the last follow-up (mean, 21 mo; range, 12-41 mo). The following variables were analyzed to determine whether they affected the outcome of the nerve transfer: the age and sex of the patient, delay from injury to surgery, body mass index (BMI), severity of trauma, and presence of rotator cuff lesions. The Spearman correlation coefficient and multiple linear regression were performed for statistical analysis.

RESULTS

The average Medical Research Council grade of deltoid muscle strength was 3.5 ± 1.1. Deltoid muscle strength correlated with the age of the patient, delay from injury to surgery, and BMI of the patient. Five patients failed to achieve more than M3 grade. Among them, 4 patients were older than 50 years and 1 was treated 14 months after injury. In the multiple linear regression model, the delay from injury to surgery, age of the patient, and BMI of the patient were the important factors, in that order, that affected the outcome of this procedure.

CONCLUSIONS

Isolated axillary nerve injury can be treated successfully with triceps motor branch transfer. However, outstanding outcomes are not universal, with one fourth failing to achieve M3 strength. The outcome of this procedure is affected by the delay from injury to surgery and the age and BMI of the patient.

Anterior deltopectoral approach for axillary nerve neurotisation

PURPOSE

To report outcome of axillary nerve neurotisation for brachial plexus injury through the anterior deltopectoral approach.

METHODS

Nine men aged 20 to 52 (mean, 27.8) years with brachial plexus injury underwent axillary nerve neurotisation through the anterior deltopectoral approach. Three of the patients had complete avulsion of C5-T1 nerve roots. The remaining 6 patients had brachial plexus injury of C5-C6 nerve roots, with associated subluxation of the glenohumeral joint, atrophy of the supraspinatus, deltoid and elbow flexors. They had no active shoulder abduction, external rotation, and elbow flexion. The pectoralis major and minor were cut and/or retracted to expose the underlying infraclavicular plexus. The axillary nerve was identified with respect to the available donor nerves (long head of triceps branch, thoracodorsal nerve, and medial pectoral nerve). In addition to the axillary nerve neurotisation, each patient had a spinal accessory nerve transferred to the suprascapular nerve for better shoulder animation.

RESULTS

Patients were followed up for 24 to 30 (mean, 26) months. In the 3 patients with C5-T1 nerve root injuries, the mean active abduction and external rotation were 63 and 20 degrees, respectively, whereas the mean abduction strength was M3 (motion against gravity). In the 6 patients with C5-C6 nerve root injuries, the mean active abduction and external rotation were 133 and 65 degrees, respectively, whereas the strength of the deltoids and triceps was M5 (normal) in all. In 4 patients with the pectoralis major cut and repaired, the muscle regained normal strength.

CONCLUSION

The anterior deltopectoral approach enabled easy access to all available donor nerves for axillary nerve neurotisation and achieved good outcomes.

Axillary nerve neurotization with the anterior deltopectoral approach in brachial plexus injuries

Combined neurotization of both axillary and suprascapular nerves in shoulder reanimation has been widely accepted in brachial plexus injuries, and the functional outcome is much superior to single nerve transfer. This study describes the surgical anatomy for axillary nerve relative to the available donor nerves and emphasize the salient technical aspects of anterior deltopectoral approach in brachial plexus injuries. Fifteen patients with brachial plexus injury who had axillary nerve neurotizations were evaluated. Five patients had complete avulsion, 9 patients had C5, six patients had brachial plexus injury pattern, and one patient had combined axillary and suprascapular nerve injury. The long head of triceps branch was the donor in C5,6 injuries; nerve to brachialis in combined nerve injury and intercostals for C5-T1 avulsion injuries. All these donors were identified through the anterior approach, and the nerve transfer was done. The recovery of deltoid was found excellent (M5) in C5,6 brachial plexus injuries with an average of 134.4° abduction at follow up of average 34.6 months. The shoulder recovery was good with 130° abduction in a case of combined axillary and suprascapular nerve injury. The deltoid recovery was good (M3) in C5-T1 avulsion injuries patients with an average of 64° shoulder abduction at follow up of 35 months. We believe that anterior approach is simple and easy for all axillary nerve transfers in brachial plexus injuries.

Computer simulation of nerve transfer strategies for restoring shoulder function after adult C5 and C6 root avulsion injuries

PURPOSE

Functional ability after nerve transfer for upper brachial plexus injuries relies on both the function and magnitude of force recovery of targeted muscles. Following nerve transfers targeting either the axillary nerve, suprascapular nerve, or both, it is unclear whether functional ability is restored in the face of limited muscle force recovery.

METHODS

We used a computer model to simulate flexing the elbow while maintaining a functional shoulder posture for 3 nerve transfer scenarios. We assessed the minimum restored force capacity necessary to perform the task, the associated compensations by neighboring muscles, and the effect of altered muscle coordination on movement effort.

RESULTS

The minimum force restored by the axillary, suprascapular, and combined nerve transfers that was required for the model to simulate the desired movement was 25%, 40%, and 15% of the unimpaired muscle force capacity, respectively. When the deltoid was paralyzed, the infraspinatus and subscapularis muscles generated higher shoulder abduction moments to compensate for deltoid weakness. For all scenarios, movement effort increased as restored force capacity decreased.

CONCLUSIONS

Combined axillary and suprascapular nerve transfer required the least restored force capacity to perform the desired elbow flexion task, whereas single suprascapular nerve transfer required the most restored force capacity to perform the same task. Although compensation mechanisms allowed all scenarios to perform the desired movement despite weakened shoulder muscles, compensation increased movement effort. Dynamic simulations allowed independent evaluation of the effect of restored force capacity on functional outcome in a way that is not possible experimentally.

CLINICAL RELEVANCE

Simultaneous nerve transfer to suprascapular and axillary nerves yields the best simulated biomechanical outcome for lower magnitudes of muscle force recovery in this computer model. Axillary nerve transfer performs nearly as well as the combined transfer, whereas suprascapular nerve transfer is more sensitive to the magnitude of reinnervation and is therefore avoided.

Comparison of nerve transfers and nerve grafting for traumatic upper plexus palsy: a systematic review and analysis

BACKGROUND

In treating patients with brachial plexus injury, there are no comparative data on the outcomes of nerve grafts or nerve transfers for isolated upper trunk or C5-C6-C7 root injuries. The purpose of our study was to compare, with systematic review, the outcomes for modern intraplexal nerve transfers for shoulder and elbow function with autogenous nerve grafting for upper brachial plexus traumatic injuries.

METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for studies in which patients had surgery for traumatic upper brachial plexus palsy within one year of injury and with a minimum follow-up of twelve months. Strength and shoulder and elbow motion were assessed as outcome measures. The Fisher exact test and Mann-Whitney U test were used to compare outcomes, with an alpha level of 0.05.

RESULTS

Thirty-one studies met the inclusion criteria. Two hundred and forty-seven (83%) and 286 (96%) of 299 patients with nerve transfers achieved elbow flexion strength of grade M4 or greater and M3 or greater, respectively, compared with thirty-two (56%) and forty-seven (82%) of fifty-seven patients with nerve grafts (p < 0.05). Forty (74%) of fifty-four patients with dual nerve transfers for shoulder function had shoulder abduction strength of grade M4 or greater compared with twenty (35%) of fifty-seven patients with nerve transfer to a single nerve and thirteen (46%) of twenty-eight patients with nerve grafts (p < 0.05). The average shoulder abduction and external rotation was 122° (range, 45° to 170°) and 108° (range, 60° to 140°) after dual nerve transfers and 50° (range, 0° to 100°) and 45° (range, 0° to 140°) in patients with nerve transfers to a single nerve.

CONCLUSIONS

In patients with demonstrated complete traumatic upper brachial plexus injuries of C5-C6, the pooled international data strongly favors dual nerve transfer over traditional nerve grafting for restoration of improved shoulder and elbow function. These data may be helpful to surgeons considering intraoperative options, particularly in cases in which the native nerve root or trunk may appear less than optimal, or when long nerve grafts are contemplated.

Nerve transfer to the triceps after brachial plexus injury: report of four cases

These case reports review the clinical outcomes of 4 patients who underwent nerve transfer to a triceps motor branch of the radial nerve. Mean follow-up was 26 ± 15 months. Two patients had a transfer using an ulnar nerve fascicle to the flexor carpi ulnaris muscle, yielding a motor recovery of grade M5 elbow extension strength in one case and M4+ in the other. In 1 patient, a thoracodorsal nerve branch was used as the donor; this patient recovered M4 strength. One patient had a transfer using a radial nerve fascicle to the extensor carpi radialis longus muscle and recovered M5 strength. These outcomes indicate that expendable fascicles of the ulnar, thoracodorsal, and radial nerves are viable donors in the surgical reconstruction of elbow extension.