MEDIAN NERVE NEUROTIZATION BY PERIPHERAL-NERVE GRAFTS DIRECTLY IMPLANTED INTO THE SPINAL-CORD - ANATOMICAL, BEHAVIORAL AND ELECTROPHYSIOLOGICAL EVIDENCES OF SENSORIMOTOR RECOVERY

Over the years, peripheral nerve grafts, a favorable environment to su pport axonal elongation, have given rise to increasing interest as a p ossible solution for promoting spinal cord repair. In the experiments described here, following an avulsion injury of the rat brachial plexu s, the median nerve was repaired by a peripheral nerve graft (PN) inse rted directly into the dorsal side of the spinal cord. Eight months la ter the animals were submitted to behavioral tests, eletrophysiologica l and histological studies. Regrowth of axons from both motoneurons an d ganglionic neurons was demonstrated following a single superficial d orsal implantation of a PN. Sensorimotor peripheral reinnervation allo wed most of the studied animals to recover enough flexor activity for grasping. Reinnervation was achieved even without prior root avulsion suggesting that the presence of a PN is sufficient to induce sprouting in the spinal cord from axotomized and non-axotomized neurons.