Long-term clinical outcomes of spinal accessory nerve transfer to the suprascapular nerve in patients with brachial plexus palsy

Efficacy of spinal accessory nerve to suprascapular nerve transfer to restore shoulder function in brachial plexus injury: A systematic review and meta-analysis

INTRODUCTION

Transfer of the spinal accessory nerve (SAN) to the suprascapular nerve (SSN) is a common surgical intervention employed for restoring shoulder function in both obstetric and traumatic brachial plexus injury (TBPI). Despite widespread use, there is a paucity of evidence surrounding the efficacy of this procedure.

METHODS

A systematic search of the literature in the National Institutes of Health MEDLINE and Embase databases was performed in accordance with the PRISMA guidelines. Patients had to have a minimum postoperative follow-up of 6 months. Cohorts containing patients with obstetric brachial plexus injuries were excluded. We extracted data on shoulder abduction strength, measured using the British Medical Research Council (MRC) scale and range of motion (ROM) of shoulder abduction.

RESULTS

Of the 298 studies screened, 12 with 311 total participants met our inclusion criteria. The average age of participants was 27.03 ± 3.05 years and the male:female ratio was 25.4:1. All patients underwent surgery following TBPI and average time-to surgery was 5.91 ± 1.52 months. 66.37 % of patients achieved a post-operative MRC grade of shoulder abduction of ≥M3 with a mean MRC score of 2.67 ± 1.02. Average post-operative shoulder abduction ROM was 56.97 degrees. Average follow-up time for all reported outcomes was 24.64 ± 7.47 weeks. Nine studies comprising 243 patients were included in the meta-analysis, which revealed a cumulative weighted effect size of 56.83 degrees (95 % CI = 52.31, 61.34).

CONCLUSION

These findings suggest that SAN-SSN transfer is an effective intervention for the restoration of shoulder function following TBPI.

Spinal accessory nerve transfer for shoulder abduction has no benefit over supraclavicular exploration and nerve grafting in brachial plexus birth injury: a systematic review

Introduction

Brachial plexus birth injury (BPBI) has an incidence of 0.9 per 1,000 live births in the population. Techniques for repair classically include supraclavicular exploration and nerve grafting (SENG) and more recently nerve transfer, namely of the spinal accessory nerve (SAN) to the suprascapular nerve (SSN) to improve functional outcomes such as glenohumeral abduction and external rotation. This systematic review was conducted to evaluate whether spinal accessory nerve transfer produced significantly better outcomes for shoulder abduction in BPBI.

Methods

A search was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analysis Individual Patient Data guidelines. Standardized comparisons were made using the Mallet Score for shoulder abduction.

Results

10 full-text articles with itemized patient outcome measures were selected. 110 patients were identified with 51 patients in the SENG group and 59 patients in the SAN transfer group. The mean shoulder abduction Mallet score in the SENG group was 3.50 ± 0.84, while the mean Mallet score in the SAN transfer group was 3.58 ± 0.77, which displayed no significant differences (p = 0.9012). There was no significant relationship between the age at time of surgery and post-operative Mallet scores for shoulder abduction after SENG (p = 0.3720).

Discussion

Our systematic review found that there was no difference observed in post-operative outcomes of shoulder abduction when comparing SAN transfer and nerve grafting. Continued support for nerve grafting lies in the argument that it incorporates the patient's native neuroanatomy and allows for sensory reinnervation.

Insights into the Medial Pectoral Nerve Transfer for Shoulder Abduction in Brachial Plexus Injuries: A Retrospective Case Series Analysis

BACKGROUND

Treatment priority in C5, C6, and C7 brachial plexus root avulsion is the recovery of shoulder function through reinnervation of shoulder muscles. The medial pectoral nerve is a potential donor for axillary nerve transfer, but outcomes are sparsely reported. This study reports the results of medial pectoral nerve transfer to the axillary nerve.

METHODS

We conducted a retrospective analysis of 12 patients with traumatic brachial plexus injury (C5, C6, and C7 root avulsion) who underwent medial pectoral nerve transfer to the axillary nerve. Sociodemographic and clinical characteristics, including electromyography findings, were documented. We assessed postoperative shoulder abduction strength and range of motion. Statistical analyses compared presurgery and postsurgery outcomes and contrasted our results with those from a study using spinal accessory nerve transfer to the suprascapular nerve.

RESULTS

Postsurgery, the mean shoulder abduction range of motion was 65.45°, with a median strength of M2. Significant improvement was noted compared to preoperative values. However, outcomes did not significantly surpass those from spinal accessory nerve transfer. Electromyography showed a low incidence of motor unit action potentials in the deltoid.

CONCLUSIONS

Medial pectoral nerve transfer to the axillary nerve did not yield superior results in shoulder abduction and deltoid reinnervation in our group of patients. At present, different nerve donors may also need to be considered for deltoid muscle reinnervation in patients with C5, C6, and C7 root avulsion to achieve better shoulder abduction recovery.

Variation in Recommended Treatment Strategies Among American Surgeons for Actual Adult Traumatic Brachial Plexus Injury Cases

PURPOSE

The surgical management of adult traumatic brachial plexus injuries (BPI) is challenging, with no consensus on optimal strategies. This study aimed to gather preferred reconstructive strategies from BPI surgeons for actual cases from a multicenter cohort to identify areas of agreement.

METHODS

Four case files (history, physical examination, and imaging and electrodiagnostic testing results) were distributed to eight self-designated Level IV expert BPI surgeons in the United States. Each surgeon independently reviewed the cases and provided a preferred reconstructive plan via free text response.

RESULTS

For a pan-plexus case after blunt trauma (67 years old; 3 months from injury): three surgeons recommended nerve grafting upper trunk roots to distal targets. There was disagreement in shoulder reconstruction: one suggested early shoulder fusion, two preferred cranial nerve XI to suprascapular nerve (SSN) transfer, and two anticipated future salvage shoulder fusion. For elbow reconstruction, six surgeons preferred intercostal nerve to musculocutaneous nerve transfer. For an upper trunk injury from a motorcycle accident (33 years old; 6 months from injury), only one surgeon recommended nerve grafting, six preferred XI to SSN transfer, all recommended triceps-to-axillary transfer, and all but one favored a double fascicular transfer.

CONCLUSIONS

There is inconsistency in the use of nerve grafting for BPI patients, especially in pan-plexus injuries where options are limited. Variability exists in shoulder reconstruction and stability management, with some advocating early glenohumeral arthrodesis. Although single fascicular and triceps-to-axillary transfers are consistently favored, there is no consensus for restoring shoulder and elbow function when intraplexal transfers are unavailable.

CLINICAL RELEVANCE

This study highlights substantial variability in surgical approaches to BPI among experts, underscoring the need for standardized treatment protocols. Understanding these diverse strategies can inform clinical decision making and help develop more uniform guidelines to improve patient outcomes.

Injury and Biological Factors Impact Shoulder Function following Autogenous Grafting of Spinal Nerves for Pan-Brachial Plexus Reconstruction

BACKGROUND

Shoulder function after spinal nerve grafting in pan-brachial plexus injuries (pan-BPI) is not well described. The authors evaluated shoulder abduction (ABD) and external rotation (ER) after spinal nerve grafting to the suprascapular nerve, axillary nerve, or posterior division of the upper trunk and determined patient characteristics, injury severity and characteristics, and nerve graft factors that influenced outcomes.

METHODS

A total of 362 patients undergoing pan-BPI reconstruction and spinal nerve grafting for shoulder reanimation in a single institution between 2001 and 2018 were reviewed. Patient demographics, Injury Severity Score (ISS), graft characteristics, strength, range of motion for shoulder ABD and ER, and patient-reported outcomes were recorded. Patients were divided into 3 groups based on recovery of shoulder function: no return, ABD only, and ABD and ER.

RESULTS

A total of 110 patients underwent spinal nerve grafting, with 41 meeting inclusion criteria. Seventeen (41.5%) had no return of shoulder function, 14 (34.1%) had ABD alone, and 10 (24.4%) had ABD and ER. Patients with recovery of both ABD and ER were significantly younger (18.6 ± 5.56 years), had lower body mass index (22.4 ± 4.0), and had a lower ISS (10.5 ± 6.24; P = 0.003). Multivariable analysis found that with increasing age (OR, 0.786; 95% CI, 0.576, 0.941) and ISS (OR, 0.820; 95% CI, 0.606, 0.979), odds for return of ABD and ER decreased significantly.

CONCLUSIONS

In pan-BPI, 24.4% of patients demonstrated return of both ABD and ER after spinal nerve grafting to suprascapular nerve and either axillary nerve or posterior division of the upper trunk. Age, body mass index, and ISS were associated with poorer recovery of shoulder function. Careful patient selection and consideration of age, body mass index, and ISS may improve outcomes of spinal nerve grafting for shoulder reanimation.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Direct Repair of Ruptured Nerve Stump to Middle Trunk for Restoration of Extrinsic Finger Extension in Total Brachial Plexus Injuries

BACKGROUND

Attempts to restore independent hand function in total brachial plexus injuries (TBPIs) have often failed due to inconsistent results of finger extension reconstruction. An innovative technique is described to achieve this effect by direct neurorrhaphy of residual (ruptured) roots with the middle trunk.

METHODS

Direct coaptation of the ruptured roots to the middle trunk and, simultaneously, transferring the anterior division of the middle trunk to the posterior division of the lower trunk was performed in 64 patients with TBPI. The return of extension of the elbow, wrist, and fingers was monitored.

RESULTS

Excellent and good muscle strength of finger extension were noted in 45.3% of cases. The patients were divided into group A (>32 years) and group B (≤32 years) according to receiver operating characteristic curve analysis. The difference of excellent and good rates of finger and wrist extension muscle strengths between the 2 groups was statistically significant (χ 2 = 4.635, P = 0.031; χ 2 = 6.615, P = 0.010).

CONCLUSIONS

Direct neurorrhaphy of ruptured nerve root stumps with the middle trunk could achieve satisfactory results for finger extension in TBPI for patients ≤32 years old. Long nerve defects (4 to 6.5 cm) could be overcome by freeing the nerve and adducting the arm against the trunk.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Combination of induced pluripotent stem cell-derived motor neuron progenitor cells with irradiated brain-derived neurotrophic factor over-expressing engineered mesenchymal stem cells enhanced restoration of axonal regeneration in a chronic spinal cord injury rat model

BACKGROUND

Spinal cord injury (SCI) is a disease that causes permanent impairment of motor, sensory, and autonomic nervous system functions. Stem cell transplantation for neuron regeneration is a promising strategic treatment for SCI. However, selecting stem cell sources and cell transplantation based on experimental evidence is required. Therefore, this study aimed to investigate the efficacy of combination cell transplantation using the brain-derived neurotrophic factor (BDNF) over-expressing engineered mesenchymal stem cell (BDNF-eMSC) and induced pluripotent stem cell-derived motor neuron progenitor cell (iMNP) in a chronic SCI rat model.

METHOD

A contusive chronic SCI was induced in Sprague-Dawley rats. At 6 weeks post-injury, BDNF-eMSC and iMNP were transplanted into the lesion site via the intralesional route. At 12 weeks post-injury, differentiation and growth factors were evaluated through immunofluorescence staining and western blot analysis. Motor neuron differentiation and neurite outgrowth were evaluated by co-culturing BDNF-eMSC and iMNP in vitro in 2-dimensional and 3-dimensional.

RESULTS

Combination cell transplantation in the chronic SCI model improved behavioral recovery more than single-cell transplantation. Additionally, combination cell transplantation enhanced mature motor neuron differentiation and axonal regeneration at the injured spinal cord. Both BDNF-eMSC and iMNP played a critical role in neurite outgrowth and motor neuron maturation via BDNF expression.

CONCLUSIONS

Our results suggest that the combined transplantation of BDNF- eMSC and iMNP in chronic SCI results in a significant clinical recovery. The transplanted iMNP cells predominantly differentiated into mature motor neurons. Additionally, BDNF-eMSC exerts a paracrine effect on neuron regeneration through BDNF expression in the injured spinal cord.

Anatomical feasibility study of the infraspinatus muscle neurotization by lower subscapular nerve

OBJECTIVES

To investigate the anatomical feasibility of the infraspinatus branch of the suprascapular nerve (IB-SSN) reconstruction by lower subscapular nerve (LSN) transfer.

METHODS

The morphological study was performed on 18 adult human cadavers. The length of the distal stump of the IB-SSN, the length of the LSN available for reconstruction and diameter of both stumps were measured. The feasibility study of the LSN to IB-SSN transfer was performed.

RESULTS

The mean length of the IB-SSN to the end of its first branch was 40.9 mm (±4.6). Its mean diameter was 2.3 mm (±0.3). The mean length of the LSN stump, which was mobilized from its original course and transferred to reach the distal stump of the IB-SSN was 66.5 mm (±11.8). Its mean diameter was 2.1 mm (±0.3). The mean ratio between LSN and IB-SSN diameters was 0.9 (±0.1). The nerve transfer was feasible in 17 out of 18 cases (94.4%).

CONCLUSION

This study demonstrates that direct LSN to IB-SSN transfer is anatomically feasible in most cases in the adult population. It may be used in cases of complex scapular fractures resulting in severe suprascapular nerve injury.

Transfer of a C7 Fascicle for the Pectoralis Major to the Suprascapular Nerve: A 3-Year Follow-Up Patient Series

BACKGROUND

In patients with C5-C6 brachial plexus injury, spinal accessory nerve transfer to the suprascapular nerve is usually performed for the restoration of shoulder abduction. In order to minimize donor deficits, we transferred one fascicle of the ipsilateral C7 root, dedicated to the pectoralis major muscle, to the suprascapular nerve.

METHODS

Ten patients with a mean age of 33 years (range, 19 to 51 years) were operated on at a mean delay of 4 months after their trauma (range, 2 to 7 months). Patients had C5-C6 brachial plexus palsy with avulsed roots on spinal magnetic resonance imaging scan. In addition to the partial C7 transfer, patients sustained nerve transfers to the posterior branch of the axillary nerve and to the motor branches of the musculocutaneous nerve for the biceps and brachialis muscles.

RESULTS

At a mean follow-up of 36 months (range, 29 to 42 months), mean shoulder abduction and external rotation ranges of motion were, respectively, 99 degrees (range, 60 to 120 degrees; p = 0.001) and 58 degrees (range, 0 to 80 degrees; p = 0.001). In nine patients, shoulder abduction strength was graded M4, according the British Medical Research Council grading scale, against 1.6 kg (range, 1 to 2 kg), and was graded M3 in one patient. External rotation strength was graded M4 in nine patients and M3 in one patient. Residual strength of the pectoralis major muscle was graded M4+ in every patient.

CONCLUSIONS

C7 partial transfer to the suprascapular nerve showed satisfactory results at long-term follow-up for active shoulder abduction and external rotation recovery in C5-C6 brachial plexus palsies. This technique replaced spinal accessory nerve transfer in the authors' practice.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

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.

Motion Analytics of Trapezius Muscle Activity in an 18-Year-Old Female with Extended Upper Brachial Plexus Birth Palsy

Background  The trapezius muscle is often utilized as a muscle or nerve donor for repairing shoulder function in those with brachial plexus birth palsy (BPBP). To evaluate the native role of the trapezius in the affected limb, we demonstrate use of the Motion Browser, a novel visual analytics system to assess an adolescent with BPBP.

Method  An 18-year-old female with extended upper trunk (C5–6–7) BPBP underwent bilateral upper extremity three-dimensional motion analysis with Motion Browser. Surface electromyography (EMG) from eight muscles in each limb which was recorded during six upper extremity movements, distinguishing between upper trapezius (UT) and lower trapezius (LT). The Motion Browser calculated active range of motion (AROM), compiled the EMG data into measures of muscle activity, and displayed the results in charts.

Results  All movements, excluding shoulder abduction, had similar AROM in affected and unaffected limbs. In the unaffected limb, LT was more active in proximal movements of shoulder abduction, and shoulder external and internal rotations. In the affected limb, LT was more active in distal movements of forearm pronation and supination; UT was more active in shoulder abduction.

Conclusion  In this female with BPBP, Motion Browser demonstrated that the native LT in the affected limb contributed to distal movements. Her results suggest that sacrificing her trapezius as a muscle or nerve donor may affect her distal functionality. Clinicians should exercise caution when considering nerve transfers in children with BPBP and consider individualized assessment of functionality before pursuing surgery.

Nerve transfer rehabilitation in tetraplegia: Comprehensive assessment and treatment program to improve upper extremity function before and after nerve transfer surgery, a case report

CONTEXT

A 28-year-old male, sustained a traumatic Spinal Cord Injury (SCI) in January 2015, and was classified as AIS A, neurological level of injury (NLI) C4. As an inpatient at the SCI rehabilitation unit, he underwent multidisciplinary assessment involving SCI specialists, peripheral nerve surgeons, psychologists, occupational and physical therapists. Team consensus determined he was a candidate for nerve transfer surgery to improve upper extremity function. The patient undertook a pre-surgical neurorehabilitation program of 3 months duration. Surgery was performed bilaterally at 11 and 13 months after SCI (right and left arm respectively).

FINDINGS

Upon completion of surgical procedures, the patient underwent an intensive post-surgical rehabilitation program based on established goals, with follow-up every 3 months, up to 24 months after the surgery. Notable improvements were wheelchair propulsion, the ability to relieve pressure, grasp, pinch, and release an object. Standardized measures for SCI individuals (SCIM-III, CUE-Q, LiSAT-9 and UEMS) showed significant improvements.

CLINICAL RELEVANCE

Nerve transfers in tetraplegia are an underused technique. The benefits of surgery along with an intensive neurorehabilitation program, can improve independence and function in daily living activities for a properly selected group of individuals.

Outcomes of Shoulder Functions in Spinal Accessory to Suprascapular Nerve Transfer in Brachial Plexus Injury: A Comparison between Anterior and Posterior Approach

Background  Restoration of shoulder functions is important in brachial plexus injury (BPI). The functional outcomes of spinal accessory nerve (SAN) to suprascapular nerve (SSN) transfer by the anterior supraclavicular approach and the posterior approach is a matter of debate. This article aims to compare the outcomes of the shoulder functions by the SAN to the SSN transfer using the two approaches. Methods  Retrospective data was collected in 34 patients who underwent SAN to SSN transfer from January 2016 to June 2018. Group A included 16 patients who underwent nerve transfers by anterior approach, and Group B included 18 patients who underwent nerve transfers by posterior approach. Functional outcomes were measured by grading the muscle power as per the British Medical Research Council (MRC) grading (graded as M) and the range of motions (ROM) of the shoulder at 6 months and 18 months. Results  Early recovery was seen in group B with 7 patients (39%) showing M1 abduction power at 6 months as compared with one patient (6%) in group A . This difference was statistically significant ( p value = 0.04). At 18 months, 10 patients (62%) in group A had good recovery (MRC grade ≥3), while 13 patients (72%) in group B had a good recovery. This difference was not found to be statistically significant (Fisher exact test p value = 0.71) There was no statistical difference in the outcomes of ROM in shoulder abduction, external rotation, and motor power at 18 months of follow-up. Conclusions  Early recovery was observed in the anterior approach group at 6 months, however, there was no significant difference in the outcomes of shoulder functions in muscle power and ROM in the two groups at 18 months of follow-up.

Nerve graft versus nerve transfer for neonatal brachial plexus: shoulder outcomes

OBJECTIVE

The decision-making in neonatal brachial plexus palsy (NBPP) treatment continues to have many areas in need of clarification. Graft repair was the gold standard until the introduction of nerve transfer strategies. Currently, there is conflicting evidence regarding outcomes in patients with nerve grafts versus nerve transfers in relation to shoulder function. The objective of this study was to further define the outcomes for reconstruction strategies in NBPP with a specific focus on the shoulder.

METHODS

A cohort of patients with NBPP and surgical repairs from a single center were reviewed. Demographic and standard clinical data, including imaging and electrodiagnostics, were gathered from a clinical database. Clinical data from physical therapy evaluations, including active and passive range of motion, were examined. Statistical analysis was performed on the available data.

RESULTS

Forty-five patients met the inclusion criteria for this study, 19 with graft repair and 26 with nerve transfers. There were no significant differences in demographics between the two groups. Understandably, there were no patients in the nerve grafting group with preganglionic lesions, resulting in a difference in lesion type between the cohorts. There were no differences in preoperative shoulder function between the cohorts. Both groups reached statistically significant improvements in shoulder flexion and shoulder abduction. The nerve transfer group experienced a significant improvement in shoulder external rotation, from -78° to -28° (p = 0.0001), whereas a significant difference was not reached in the graft group. When compared between groups, there appeared to be a trend favoring nerve transfer in shoulder external rotation, with the graft patients improving by 17° and the transfer patients improving by 49° (p = 0.07).

CONCLUSIONS

In NBPP, patients with shoulder weakness experience statistically significant improvements in shoulder flexion and abduction after graft repair or nerve transfer, and patients with nerve transfers additionally experience significant improvement in external rotation. With regard to shoulder external rotation, there appear to be some data supporting the use of nerve transfers.

Anatomical aspects of the selective infraspinatus muscle neurotization by spinal accessory nerve

The suprascapular nerve (SSN) is commonly reconstructed by spinal accessory nerve (SAN) transfer. However, reinnervation of its branch to the infraspinatus muscle (IB-SSN) is poor. Reconstruction of the SSN in cases of scapular fractures is frequently neglected in clinical practice. The morphological study was performed on 25 adult human cadavers. The course and the length of SSN of minimal diameter of 2 mm within the trapezius muscle, the length of the distal stump of IB-SSN to its branching point and the length of the SSN available for reconstructive procedure were measured. The feasibility study of the SAN - IB-SSN neurotization performed by using a bony canal under the spine of scapula was performed. The mean distance of the SAN from the spine was 8.5 cm (±0.88) at the point where it perforates the trapezius muscle and 4.49 cm (±0.72) at the most distal part of the nerve. The mean length of the intramuscular portion of the nerve was 14.74 cm (±1.99). It ran under a mean latero-medial angle of 15.54^° (±2.51). The mean distance between the medial end of the scapular spine and the SAN was 2.44 cm (± 0.64). The mean length of the IB-SSN was 3.6 cm (± 0.67). The mean length of the SAN stump which was mobilized from its original course and transferred to the infraspinous fossa to reach distal stump of the IB-SSN was 8.09 cm (±1.6). Direct SAN to IB-SSN transfer is anatomically feasible in the adult population.

Reanimation of triceps muscle using ulnar nerve fascicle transfer to the nerve to long head of the triceps muscle

BACKGROUND

Triceps muscle serves an important role in extension of the elbow. Its action is required for reaching out objects without using the trunk. Elbow extension is an important function for natural stabilization of the elbow. The aim of this study was to evaluate restoration of elbow extension in adults suffering triceps muscle palsy with various causes, by using transfer of a fascicle of ulnar nerve to the long head of triceps branch of the radial nerve.

MATERIALS AND METHODS

In the present case series, 7 patients with partial brachial plexus injury or posterior cord injury, where triceps muscle was involved, were subjected to motor fascicle of ulnar nerve transfer to the nerve to long head of triceps for restoration of elbow extension. Follow-ups, including EMG-NCV (electromyography-nerve conduction velocity) 6 and 12 months after surgery and elbow extension muscle strength using MRC grading, were carried out.

RESULTS

Six patients (85.71%) achieved a functional muscle strength of M4 for their elbow extension. In all of the patients, re-innervation was discovered using EMG-NCV.

CONCLUSION

This surgical technique (ulnar nerve fascicle transfer to long head of the triceps) for improving elbow extension is promising in patients with brachial plexus injury.

Intercostal or ulnar nerve: Which donor nerve is to be used for reanimation of elbow flexion?

BACKGROUND

In total brachial plexus injury, intercostal nerves (ICNs) are used as donor nerves to restore the elbow flexion; albeit in upper brachial plexus injury (BPI), ulnar nerve provides a source of motor axons for this purpose. The present study set out to compare the restoration of elbow flexion by using these two donor nerves.

METHODS

Between 2010 and 2013, 24 adult patients with upper-middle BPI and 15 patients with total BPI undergoing elbow flexion restoration surgery were studied. Motor fascicle of flexor carpi ulnaris branch of ulnar nerve (mFCU nerve) procedure was utilized in upper-middle BPI, as well as transfer of ICN to biceps branch of the musculocutaneous nerve (MCN) in total BPI. Both techniques included sectioning, rerouting, and direct suturing of the biceps branch of the MCN. Follow-up consisted serial clinical examinations and EMG-NCV tests. Motor strength was recorded according to the British Medical Research Council grading system in that the results were reported as nonfunctional (grades M0-M2) and functional (grades M3-M5).

RESULT

No significant difference was documented between the Oberlin procedure and ICN-MCN transfer in terms of reinnervation results (P = 0.6). However, a significant difference in restoration of muscle force was found between the mFCU (95.83%) and ICN-MCN transfers (66.66%) (P = 0.02).

CONCLUSION

The evidence from the present study indicates that although ICN-MCN transfer is a viable method for reanimation of elbow flexion in BPI, mFCU nerve is a better donor if exists.

Comparison of spinal accessory nerve transfer to supra-scapular nerve vs. shoulder arthrodesis in adults with brachial plexus injury

BACKGROUND

Restoring shoulder mobility, stability, and strength is a key goal in patients with brachial plexus injuries. Shoulder arthrodesis is chiefly used as an adjunct to, or after failure of, initial direct nerve surgery. The objective of this study was to compare clinical and functional shoulder outcomes after direct nerve transfer vs. shoulder arthrodesis in adults with supra-clavicular brachial plexus injuries.

HYPOTHESIS

Shoulder arthrodesis, currently used as a salvage procedure in brachial palsy injuries, deserves to be viewed to a valid alternative to direct nerve transfer.

MATERIAL AND METHODS

A retrospective study was conducted in 58 patients with a follow-up of at least 2 years. Among them, 20 were managed by transfer of a spinal accessory nerve fascicle to the supra-scapular nerve and 38 by shoulder arthrodesis. Outcome measures were shoulder range-of-motion, isometric shoulder strength, and the Disabilities of the Arm, Shoulder, and Hand (DASH) score.

RESULTS

Mean age at surgery was 24 years and mean follow-up was 46 months (range, 24-156 months). Motion ranges of the shoulder were not significantly different between the two treatment groups. Data variance was significantly greater in the nerve transfer group than in the shoulder arthrodesis group for scapular antepulsion (p=0.0011), abduction (p<0.001), and external rotation (p=0.0066). Strength was significantly greater in the arthrodesis group in all directions of motion. The DASH scores showed no significant between-group differences.

CONCLUSIONS

The results of this study conflict with the widely help opinion that nerve transfer to the supra-scapularis nerve produces better clinical outcomes compared to shoulder arthrodesis. Nerve transfer was not better than shoulder arthrodesis in our patients. The data variance heterogeneity suggests poor predictability and reliability of nerve transfer, in contrast to the modest but predictable and uniform results of shoulder arthrodesis.

LEVEL OF EVIDENCE

IV, retrospective observational comparative study.

A First-in-Human, Phase I Study of Neural Stem Cell Transplantation for Chronic Spinal Cord Injury

We tested the feasibility and safety of human-spinal-cord-derived neural stem cell (NSI-566) transplantation for the treatment of chronic spinal cord injury (SCI). In this clinical trial, four subjects with T2-T12 SCI received treatment consisting of removal of spinal instrumentation, laminectomy, and durotomy, followed by six midline bilateral stereotactic injections of NSI-566 cells. All subjects tolerated the procedure well and there have been no serious adverse events to date (18-27 months post-grafting). In two subjects, one to two levels of neurological improvement were detected using ISNCSCI motor and sensory scores. Our results support the safety of NSI-566 transplantation into the SCI site and early signs of potential efficacy in three of the subjects warrant further exploration of NSI-566 cells in dose escalation studies. Despite these encouraging secondary data, we emphasize that this safety trial lacks statistical power or a control group needed to evaluate functional changes resulting from cell grafting.

Traumatic brachial plexus injury: a study of 510 surgical cases from multicenter services in Guangxi, China

BACKGROUND

Traumatic brachial plexus injuries are severe lesions, and the incidence of these injuries has been increasing in recent years.

METHODS

The clinical data of 510 operated patients with brachial plexus injury recruited from 74 hospitals in Guangxi from 2004 to 2016 were retrospectively studied.

RESULTS

Our study included 447 males and 63 females, with an average age of 29.04 years. Traffic accidents were the most common cause of injury (64.71%), especially motorcycle accidents. Closed injuries accounted for 88.24% of cases, and 83.53% of patients had associated injuries, the most common of which were fractures (76.27%). The preoperative predictive value of root injury of MRI and CT was 74.71% and 71.28%, respectively. 44.71% of patients underwent an initial operation within 6 months after the trauma. Regarding the surgery, neurolysis alone, brachial plexus reconstruction, and free functioning gracilis graft accounted for 16.67%, 75.50%, and 4.51%, respectively. A total of 415 patients were followed up with an average time of 47.95 (25-68) months, and anxiety or depression were found among 81.20% of them. Two hundred seventy-six patients suffered from nerve pain, with mild pain present in 67.03% of patients. Additionally, 347 patients were followed up for more than 3 years, 76.81% of patients with C5-C6 injury recovery to useful function, and the procedure of neurolysis alone demonstrated the best efficacy (79.45%).

CONCLUSIONS

Brachial plexus injury is still a challenging trauma for surgeons, and traffic accidents are the dominant cause. Timely and effective surgery is important for functional limb recovery.

Double Fascicular Nerve Transfer to Musculocutaneous Branches for Restoration of Elbow Flexion in Brachial Plexus Injury

Background

Restriction of elbow flexion significantly limits upper extremity function following brachial plexus injuries. In recent years, the double fascicular nerve transfer procedure utilizing ulnar and median nerve transfer to musculocutaneous branches has shown promising functional outcomes.

Objective

To evaluate restoration of elbow flexion following a double fascicular transfer in patients with brachial plexus injuries and identify predictors of poor outcomes.

Methods

This retrospective review included 10 consecutive patients with brachial plexus injuries involving C5-C6 root avulsions who underwent the double nerve transfer procedure. The mean follow-up was 12 months and the primary outcome was assessment of elbow flexion with the use of the Medical Research Council (MRC) scale.

Results

This procedure achieved elbow flexion of MRC grade M3 or higher in 50% of our cohort. Time interval from injury to surgery showed a statistically significant inverse association with functional recovery (r = -0.73, p = 0.016). Patients who had the surgery within six months of the injury, demonstrated higher MRC grades during the follow-up (p = 0.048). There was no association between elbow flexion recovery and age, body mass index (BMI), gender, hypertension, diabetes or smoking status.

Conclusions

The double fascicular transfer to musculocutaneous may be a safe and effective treatment for restoration of elbow flexion. The procedure is associated with superior functional outcomes when performed within the first six months from the injury.

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.

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.

Double nerve transfer for restoration of hand grasp and release in C7 tetraplegia following complete cervical spinal cord injury

Cervical spinal cord injury (SCI) can cause tetraplegia. Nerve transfer has been routinely utilized for reconstruction of hand in brachial plexus injuries. Here, we report reconstruction of finger flexion (hand grasp) and extension (hand release) in a victim of cervical spinal cord injury with tetraplegia. We also focus on importance of extension phase in restoration of hand function in the tetraplegic case, in addition to provision of a detailed description of both operations including text, photographs, and a video. We used double nerve transfer, namely brachialis branches of musculocutaneous nerve to anterior interosseous nerve (AIN) and supinator branch of radial nerve to posterior interosseous nerve (PIN). We found that brachialis nerve transfer to AIN (for finger flexion) and supinator branch nerve transfer to PIN (for finger extension) can provide finger flexion and extension simultaneously. Brachialis nerve transfer to AIN and supinator branch nerve transfer to PIN may be an acceptable surgical technique to restore hand grasp and release in tetraplegia after SCI.

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.

Successful recovery of sensation loss in upper brachial plexus injuries

OBJECTIVE

Injuries of the upper trunk of the brachial plexus may trigger motor and sensory deficits. There exists a growing body of literature with respect to the reconstruction of motor deficits in upper trunk brachial plexus injuries by using nerve transfers; albeit to date, very few old reports have focused on the reconstruction of sensory loss resulting from upper trunk injuries. In this case series, we review six cases (five males and one female) with upper trunk brachial plexus injuries undergoing sensory nerve transfers.

METHODS

Sensory reconstruction was carried out by using transfer of the ulnar to the median nerves, innervating adjacent aspects of the little and ring fingers (the fourth web space) and adjacent aspects of the thumb and the index finger (the first web space), respectively.

RESULTS

The mean age of our six patients was 30.5 ± 9 years old (range 20-45). The mean time interval between the injury and subsequent surgery was 6.6 ± 1.8 months (range 5-10). Five patients achieved S3 or S3+ in both the thumb and the index finger while the sixth one regained S2+ in the index finger while also achieving S3 in the thumb according to the Highet-Zachary system scoring scale.

CONCLUSION

These results suggest that nerve transfers can achieve satisfactory outcomes in patients having sensory reconstruction after upper brachial plexus injuries, and thus, we lay emphasis on reviving the use of sensory nerve transfer techniques in such patients.

Spinal accessory nerve to triceps muscle transfer using long autologous nerve grafts for recovery of elbow extension in traumatic brachial plexus injuries

OBJECTIVE

Reconstructive options for brachial plexus lesions continue to expand and improve. The purpose of this study was to evaluate the prevalence and quality of restored elbow extension in patients with brachial plexus injuries who underwent transfer of the spinal accessory nerve to the motor branch of the radial nerve to the long head of the triceps muscle with an intervening autologous nerve graft and to identify patient and injury factors that influence functional triceps outcome.

METHODS

A total of 42 patients were included in this retrospective review. All patients underwent transfer of the spinal accessory nerve to the motor branch of the radial nerve to the long head of the triceps muscle as part of their reconstruction plan after brachial plexus injury. The primary outcome was elbow extension strength according to the modified Medical Research Council muscle grading scale, and signs of triceps muscle recovery were recorded using electromyography.

RESULTS

When evaluating the entire study population (follow-up range 12–45 months, mean 24.3 months), 52.4% of patients achieved meaningful recovery. More specifically, 45.2% reached Grade 0 or 1 recovery, 19.1% obtained Grade 2, and 35.7% improved to Grade 3 or better. The presence of a vascular injury impaired functional outcome. In the subgroup with a minimum follow-up of 20 months (n = 26), meaningful recovery was obtained by 69.5%. In this subgroup, 7.7% had no recovery (Grade 0), 19.2% had recovery to Grade 1, and 23.1% had recovery to Grade 2. Grade 3 or better was reached by 50% of patients, of whom 34.5% obtained Grade 4 elbow extension.

CONCLUSIONS

Transfer of the spinal accessory nerve to the radial nerve branch to the long head of the triceps muscle with an interposition nerve graft is an adequate option for restoration of elbow extension, despite the relatively long time required for reinnervation. The presence of vascular injury impairs functional recovery of the triceps muscle, and the use of shorter nerve grafts is recommended when and if possible.

The phrenic nerve transfer in the treatment of a septuagenarian with brachial plexus avulsion injury: a case report

Phrenic nerve transfer has been a well-established procedure for restoring elbow flexion function in patients with brachial plexus avulsion injury. Concerning about probably detrimental respiratory effects brought by the operation, however, stirred up quite a bit of controversy. We present a case report of the successful application of phrenic nerve as donor to reinnervate the biceps in a septuagenarian with brachial plexus avulsion injury, not accompanied with significant clinical respiratory problem.