Objective: The objective of this study was to evaluate the outcome of patients treated with contralateral C7 (cC7) transfer and to determine the factors that affect the outcome of this procedure. Materials and Methods: A retrospective review of 73 patients with total brachial plexus root avulsion injury (BPAI) who underwent cC7 transfer was conducted. All of the surgeries were performed by 2 stages, and the pedicled ulnar nerve was the bridged nerve. The 73 patients were divided into 2 groups according to different number of the recipient nerves. In group 1 (51 patients), the cC7 nerve was used to transfer to median nerve only. The entire cC7 was used in 11 patients; the posterior division together with the lateral part of the anterior division was used to transfer to median nerve in 15 patients; and the anterior or the posterior division alone was used to transfer to median nerve in 25 patients. In group 2, the cC7 nerve was used to transfer to 2 nerves simultaneously. The entire cC7 was used to transfer to median nerve and biceps branch in 12 patients and to median nerve and triceps branch in 10 patients. The mean follow-up period was 7.3 years. Results: The efficient of these 73 patients was 54.8% in wrist and finger flexor, 57.5% in median nerve area sensation, 66.7% in the elbow flexor, and 20% in the elbow extensor. The patients with entire cC7 root transfer achieved significantly better recovery than the patients with partial cC7 root transfer. The best function recovery could be induced if the interval between 2 stages was 4 to 8 months. Functional recovery of biceps branch was significantly better than that of triceps branch. Conclusion: Contralateral C7 transfer is an effective procedure in treating total BPAI patients. If transferred to single nerve, the entire C7 root transfer can obtain significantly better recovery, and we emphasize using the entire root as the donor. The optimal interval between 2 surgery stages is 4 to 8 months. If transferred to 2 nerves, the 2 recipient nerves should be collaborative in motor function.
