Graft of pre-injured sural nerve promotes regeneration of corticospinal tract and functional recovery in rats with chronic spinal cord injury

A possible treatment approach for chronic spinal cord injuries has been tested. We report that minced, autologous, pre-injured peripheral nerve administered as a single injection into an injury-induced cyst, resulting from a contusion injury of the thoracic spinal cord, stimulates recovery of hindlimb locomotor function in rats, as measured by the Basso, Beattie, Bresnahan Locomotor Rating Scale. This response was further enhanced by the addition of exogenous neurotrophic factors. Histological analysis showed axons of the corticospinal tract exhibited significant regeneration past the injury site, when quantified both by number and length. Results indicate that the use of a pre-injured peripheral nerve graft stimulates chronically injured descending nerves to overcome a local inhibitory environment. The resulting sprouting and growth past the injury site is associated with a significant improvement in locomotor function.