Electrophysiological study of nerve grafting.

After using the sural nerve for cable grafting in three children with nerve defects of the upper limb, we conducted electrophysiological studies on the regeneration of the nerve. After nerve grafting, nerve regeneration was delayed as compared to that of the end-to-end suture, but muscle power recovered to 80% of normal. Electromyography showed isolated motor unit potentials with high amplitude and polyphasic waves at maximum voluntary contraction. The motor conduction velocity recovered to about 70% of the normal level, but the sensory conduction velocity was less than this. The motor conduction velocity was delayed in the graft site, which, for measurement purposes, included the two suture lines.