Restoration of hand function and so called "breathing arm" after intraspinal repair of C5-T1 brachial plexus avulsion injury. Case report.

This 9-year-old boy sustained a complete right-sided C5-T1 brachial plexus avulsion injury in a motorcycle accident. He underwent surgery 4 weeks after the accident. The motor-related nerve roots in all parts of the avulsed brachial plexus were reconnected to the spinal cord by reimplantation of peripheral nerve grafts. Recovery in the proximal part of the arm started 8 to 10 months later. Motor function was restored throughout the arm and also in the intrinsic muscles of the hand by 2 years postoperatively. The initial severe excruciating pain, typical after nerve root avulsions, disappeared completely with motor recovery. The authors observed good recruitment of regenerated motor units in all parts of the arm, but there were cocontractions. Transcranial magnetic stimulation produced response in all muscles, with prolonged latency and smaller amplitude compared with the intact side. There was inspiration-evoked muscle activity in proximal arm muscles--that is, the so-called "breathing arm" phenomenon. The issues of nerve regeneration after intraspinal reimplantation in a young individual, as well as plasticity and associated pain, are discussed. To the best of the authors' knowledge, the present case demonstrates, for the first time, that spinal cord surgery can restore hand function after a complete brachial plexus avulsion injury.