Partial ipsilateral C7 transfer to the upper trunk for C5-C6 avulsion of the brachial plexus

Ipsilateral whole C7 root transfer has been reported in treating C5-C6 avulsion. To minimize donor deficits, partial ipsilateral C7 (PIC7) transfer was developed.

To investigate the long-term results of PIC7 transfer to the upper trunk in treating C5-C6 avulsion of the brachial plexus.

We prospectively studied 8 young adults with C5-C6 avulsion. Five patients (group A) who also had spinal accessory nerve (SAN) injury underwent PIC7 transfer to the upper trunk. The other 3 patients (group B) without SAN injury underwent a combination of PIC7 to the upper trunk and the SAN to the suprascapular nerve (SSN). Postsurgical evaluations including donor deficits, functional recovery, and co-contraction of the muscles were performed 1 week later and then at intervals of 3 months.

After a mean period of 39.2 months, all subjects were found to have gained elbow flexion of 110 to 150° with muscle strength of M4-5. The patients in group B achieved external rotation of 60 to 70° at M3-4, and 2 achieved shoulder abductions approaching 180° at M4. The patients in group A showed no active external rotation and shoulder abduction of 25 to 50° at M2-3. The temporary deficits caused by PIC7 transfer disappeared in all subjects within the first 3 months. Co-contraction of the latissimus dorsi against the deltoid was recorded in group A but not in group B.

PIC7 transfer, when combined with SAN transfer to SSN as a novel approach, is a safe, easy, and efficacious surgical procedure for patients with simple C5-C6 avulsion.