Transfer of the rhomboid nerve for restoration of shoulder external rotation in partial brachial plexus palsy

Abstract

Restoration of shoulder external rotation in partial brachial plexus palsies is a real challenge. The transfer of the spinal accessory nerve to the suprascapular nerve remains the gold standard. This transfer, however, cannot be always performed. Therefore, in these cases, we previously proposed the transfer of the rhomboid nerve to the suprascapular nerve through a posterior approach. The goal of the present study is to assess this technique through a short series. Eight male patients had a partial plexus palsy. Five patients had C5, C6 root injuries, two patients had C5, C6, C7 root injuries, and one patient had C5 to C8 root injuries. No patients had C5 or C6 root avulsions. In one patient, the spinal accessory nerve was injured and in seven patients, the proximal suprascapular nerve was not available. All patients underwent a transfer from the rhomboid nerve to the suprascapular nerve. Concerning shoulder elevation, transfers from the branch of the long head of the triceps or ulnar nerve fascicle were transferred to the axillary nerve. For elbow flexion, fascicles from the ulnar nerve, median nerve, or both were used. For elbow extension, three intercostal nerves in one patient and one fascicle from the ulnar nerve in two patients were transferred to the branch of the long head of the triceps. For wrist and finger extension, palliative surgery was proposed. All patients recovered external shoulder rotation (from 70-110º) and shoulder elevation (range, 80-140º). Active elbow flexion was coded M4 in seven patients and M3 in one patient. All patients recovered active elbow extension. The transfer of the rhomboid nerve to the suprascapular nerve is an efficient procedure for shoulder external rotation in partial brachial plexus palsies without C5 root avulsion. The results in terms of range-of-motion are, however, poorer than with the spinal accessory nerve. Therefore, this technique is appropriate if the spinal accessory nerve is injured or if the suprascapular nerve is not available in the cervical area. This technique must be associated with another transfer to the axillary nerve for shoulder elevation. The study of more patients will be necessary to confirm these results.

Keywords: Brachial plexus; Rhomboid nerve; Shoulder external rotation; Suprascapular nerve.