Bypass coaptation for cervical root avulsion: indications for optimal outcome.

Objective: Previously, we reported bypass coaptation of the C3 and C4 anterior rami to the upper trunk of the brachial plexus for restoration of the muscles denervated as a result of C5 and C6 nerve root avulsion. This procedure is thought to be superior to the transfer of individual peripheral nerve fibers to the brachial plexus branches. Therefore, the benefits of the bypass coaptation procedures in the treatment of various root avulsions are presented.

Methods: Twenty-six patients were selected as suitable candidates for bypass coaptation procedures. They were divided into 3 groups: 1) Erb-Duchenne palsy due to C5 and C6 root avulsion, 2) Klumpke palsy due to C8 and T1 root avulsion, and 3) the flail arm (or flail upper limb) due to C5 through T1 root avulsion. The surgical techniques are described in detail.

Results: The coaptation procedures for the first group resulted in excellent recovery of all the denervated muscles. The patients in the second group showed reinnervation of the finger muscles and finger sensory distributions in infants within the first year after surgery. The flail arm group regained satisfactory proximal muscle function but only mild distal muscle function. One exception was a child who showed significant recovery in proximal and distal motor and sensory function.

Conclusion: We recommend the bypass coaptation as a useful procedure for the following categories: Erb-Duchenne palsy due to C5 and C6 root avulsion in all ages, Klumpke palsy due to the C8 and T1 avulsion, and the flail arm due to C5 through T1 avulsion in young children. However, bypass procedures for the flail limb in adults require additional innovative methods to facilitate the growth rate of regenerating nerves.