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

Abstract

For the reconstruction of brachial plexus lesions, restoration of elbow flexion and shoulder function is fundamental and is achieved by dual nerve transfers. Shoulder stabilization and movement are crucial in freedom of motion of the upper extremity. In patients with C5-C6 brachial plexus injury, spinal accessory nerve transfer to the suprascapular nerve and a fascicle of ulnar nerve to musculocutaneous nerve (dual nerve transfer) are carried out for restoration of shoulder abduction and elbow flexion, respectively. In the present study, we evaluated the long-term clinical outcomes of spinal accessory nerve transfer to the suprascapular nerve for restoration of shoulder abduction in patients with brachial plexus palsy undergoing a dual nerve transfer. In the present retrospective review, 22 consecutive subjects with upper brachial plexus palsy were assessed. All of the subjects underwent spinal accessory nerve transfer to the suprascapular nerve and a dual nerve transfer from the ulnar nerve to the biceps branch and from the median nerve to the brachialis branch of the musculocutaneous nerve simultaneously. All of the subjects were followed up for 18 to 24 months (average, 21.7 months) for assessing the recovery of the shoulder abduction and motor function. Spinal accessory nerve transfer to the suprascapular nerve showed a motor function recovery of M3 and M4 in 13.6 and 63.6% of the subjects, respectively. However, 22.7 % of the subjects remained with a motor function of M2. The mean of shoulder abduction reached 55.55 ± 9.95° (range, 40-72°). Altogether, good functional results regained in 17 out of 22 the subjects (77.2 %). Linear regression analysis showed that advanced age was a predictor of low motor functional grade. The evidence from the present study suggests that transferring spinal accessory nerve to the suprascapular nerve for restoring shoulder abduction is an effective and reliable treatment with high success rate in patients with brachial plexus palsy, especially in young patients.