Peripheral nerve grafting in the spinal cord: a histological and electrophysiological study.

Excision of the dorsal columns was used to create a lesion in the spinal cord. The defect was bridged using a peripheral nerve graft. Silver staining showed the grafts being invaded by axons. Neuronal tracing by injecting horseradish peroxidase into the graft showed the origin of these fibres to be in dorsal root ganglia and in the grey matter of the lumbar cord. All of the animals studied showed horseradish peroxidase staining of neurones in the grey matter of the lumbar cord caudal to the graft. Five of the animals had staining of the dorsal root ganglion cells. Electro-physiological assessment was performed 5 to 6 months following the grafting procedure. Evoked potentials were recorded from the graft in six animals and from the dorsal columns above the graft in six animals.