Contralateral C7 Transfer via Both Vascularized Ulnar Nerve and Medial Antebrachial Cutaneous Nerve With the Ulnar Artery Anastomosed to the Arteria transversa Colli to Repair Brachial Plexus Avulsion

Abstract

Background: Contralateral C7 nerve transfer to the median nerve has been used in an attempt to restore finger flexion in patients with total brachial plexus avulsion injury. However, the results have not been satisfactory mainly because of the requirement to use a long bridging nerve graft, which causes an extended nerve regeneration process and irreversible muscle atrophy. A new procedure involving contralateral C7 nerve transfer via both vascularized ulnar nerve and medial antebrachial cutaneous nerve with the ulnar artery anastomosed to the arteria transversa colli is presented here. Methods: It was performed in 25 patients with total brachial plexus avulsion injury. Contralateral C7 nerve root was coapted to the distal end of the ipsilateral vascularized ulnar nerve and medial antebrachial cutaneous nerve with the ulnar artery is anastomosed to the arteria transversa colli. The ulnar nerve was secured to the median nerve, and medial antebrachial cutaneous nerve was used to repair musculocutaneous nerve. Electromyography and ultrasonography were used to evaluate the early recovery. Recovery of finger, wrist, and elbow flexion was evaluated with the use of the modified British Medical Research Council muscle grading system. Results: Electromyography showed the early recovery by 3 months postoperatively, and smooth blood flow at the anastomotic stoma can be seen through ultrasound. The mean follow-up period (and standard deviation) was 20 ± 6 months. Motor function with a grade of M3+ or greater was attained in 60% of the patients for elbow flexion, 64% of the patients for finger flexion, 53% of the patients for thumb flexion, and 72% of the patients for wrist flexion. Conclusions: Contralateral C7 nerve transfer via both vascularized ulnar nerve and medial antebrachial cutaneous nerve with the ulnar artery anastomosed to the arteria transversa colli speeds up the nerve regeneration in patients with total brachial plexus avulsion injury and improve the utilization of contralateral C7 fiber. There was satisfactory recovery of finger flexion and wrist flexion in this series.