RETURN OF FUNCTION AFTER SPINAL-CORD IMPLANTATION OF AVULSED SPINAL NERVE ROOTS

Avulsion of nerve roots from the spinal cord is widely regarded as an untreatable injury. However, a series of experiments in animals has sh own that, if continuity is restored between spinal cord and ventral ro ots, axons from spinal motor neurons can regrow into the peripheral ne rves with recovery of motor function. These observations were applied in the treatment of a man with avulsion of the 6th cervical (C6) to 1s t thoracic roots due to brachial plexus injury. Two ventral roots were implanted into the spinal cord through slits in the pia mater, C6 dir ectly and C7 via sural nerve grafts. Voluntary activity in proximal ar m muscles was detected electromyographically after nine months and cli nically after one year. After three years the patient had voluntary ac tivity (with some co-contraction) in the deltoid, biceps, and triceps muscles. To determine whether the improvement was due to spontaneous r ecovery from C5, the C5 root was blocked pharmacologically, and the re sults indicated that the repaired roots were contributing substantiall y to motor function. Repair of spinal nerve roots deserves further exp loration in management of brachial plexus injury.