Partial Contralateral C7 Transfer in Adult Brachial Plexus Lesions—Results after Five Years

Within the last decade, contralateral C7 transfer has become a new source of axon donors in complete brachial plexus lesions.

Between 1995 and 2001, 10 adult patients were treated. The authors used a two-stage procedure with exploration and extraplexual neurotization of the suprascapular nerve using half the spinal acessory nerve. Depending on intraoperative findings, the musculocutaneous nerve was neurotized by the phrenic nerve at the time of primary operation, or secondarily neurotized by the contralateral C7 root. If the musculocutaneous nerve could be neurotized by the phrenic nerve, C7 transfer was used to reinnervate the median nerve. If possible, the vascularized ulnar nerve graft or, if not available, two sural nerves were used.

Neurotization of the musculocutaneous nerve was carried out in six patients, and of the median nerve in four patients with more than 3 years of follow-up. Criteria for evaluation were donor-site morbidity, classification, time for recovery, time for autonomization, and functional result. Successful elbow flexion was achieved if muscle power was > M3; successful median nerve motor function was achieved if a primitive power grip pattern was demonstrated.

All patients complained of temporary paresthesia in the dorsal part of P3 of the thumb, index, and middle finger. There was complete sensory recovery at the 3-month postoperative examination. There was no clinically evident motor loss at the donor extremity. A successful elbow flexion, i.e. muscle power > M3, was achieved in all six patients after 9 to 15 months. Four of six patients were able to use this function individually. In the other two patients, a start command must be given voluntarily from the contralateral side (contraction of the contralateral latissimus dorsi muscle). A functional primitive grip pattern was achieved in one of four patients after 18 months. In three patients, although there was some movement, this movement must be judged “academic” at present.

The C7 transfer was demonstrated to be a safe transfer if, at the time of operation, no fascicles innervating wrist and finger extension were taken. Providing there is adequate biceps muscle organ function, active elbow flexion can be reconstructed in most of the patients. However, for median nerve innervation, motor results are moderate up to now.