Postoperative ulnar neuropathy.

Although compressive ulnar neuropathy developing during surgical procedures under general anesthesia has been recognized, clinical and electrophysiological features of this neuropathy have been incompletely described. During the past two years, we have seen eight patients with this complication, mainly following intra-abdominal or intrathoracic operations. Neuropathy was associated with a persistent severe deficit during a mean follow-up of 23.5 months (range, six to 96 months) after operation. Electrophysiological studies verified substantial Wallerian degeneration in the majority of patients. Clinical and electrophysiological data, as well as intraoperative findings in some patients, suggest that compression occurred at the cubital tunnel. These patients with ulnar neuropathy had a particularly poor prognosis, whether treated surgically (decompression or transposition) or medically. Prevention of ulnar nerve compression during major operations therefore assumes paramount importance.