Evaluation of suprascapular nerve neurotization after nerve grafting or transfer in the treatment of brachial plexus traction lesions

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>The aim of this retrospective study was to evaluate the restoration of shoulder function by means of supra-scapular nerve neurotization in adult patients with proximal C-5 and C-6 lesions due to a severe brachial plexus traction injury (BPTI). The primary goal of brachial plexus reconstructive surgery was to restore the biceps muscle function and, secondarily, to reanimate shoulder function.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Suprascapular nerve neurotization was performed by grafting the C-5 nerve in 24 patients and by accessory or hypoglossal nerve transfer in 29 patients. Additional neurotization involving the axillary nerve could be performed in 18 patients.</jats:p> <jats:p>Postoperative needle electromyography studies of the supraspinatus, infraspinatus, and deltoid muscles showed signs of reinnervation in most patients; however, active glenohumeral shoulder function recovery was poor. In nine (17%) of 53 patients supraspinatus muscle strength was Medical Research Council (MRC) Grade 3 or 4 and in four (8%) infraspinatus muscle power was Grade 3 or 4. In 18 patients in whom deltoid muscle reinnervation was attempted, MRC Grade 3 or 4 function was demonstrated in two (11%). In the overall group, eight patients (15%) exhibited glenohumeral abduction with a mean of 44 ± 17° (standard deviation [SD]) (median 45°) and four patients (8%) exhibited glenohumeral exorotation with a mean of 48 ± 24° (SD) (median 53°). In only three patients (6%) were both functions regained.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>The reanimation of shoulder function in patients with proximal C-5 and C-6 BPTIs following supra-scapular nerve neurotization is disappointingly low.</jats:p></jats:sec>

Improved Technique for Harvesting the Accessory Nerve for Transfer in Brachial Plexus Injuries

“…Other surgeons (8) have proposed that poor results might be related to double lesions of the suprascapular nerve. Double lesions, however, were not identified in our previous studies if the suprascapular nerve was explored in the scapular notch.…”

“…Transfer of the accessory nerve to the suprascapular nerve is widely used to reconstruct shoulder abduction and external rotation (7). Indeed, the results of this transfer are superior to grafts from the non-avulsed C5 root to the suprascapular nerve (3,8,9). The accessory nerve has also been used to reconstruct the musculocutaneous nerve or lateral cord, with encouraging results (1,4,11,12,13).…”

“…The nerve is then dissected as far as possible to the undersurface of the trapezius muscle (6). Alternatively, the anterior border and surface of the trapezius muscle are located, and, with the help of electric stimulation, the accessory nerve is identified and dissected distally (3,8). To locate the nerve more precisely, we advocate following the cervical transverse vessels up to their entrance into the trapezius muscle.…”

Dorsal Approach in Transfer of the Distal Spinal Accessory Nerve Into the Suprascapular Nerve: Histomorphometric Analysis and Clinical Results in 14 Cases of Upper Brachial Plexus Injuries

“…Since then, it has been extensively used by many workers. [7][8][9] In a meta-analysis, Merrell et al 10 concluded that transferring the SAN into the SSN represented the most suitable option for restoration of shoulder abduction. Nagano 11 noted that double-or triple-level injury in the SSN is a frequent occurrence that could possibly explain the poor postoperative nerve transfer results associated with weakness in the infraspinatus muscle.…”