The use of intraoperative electrophysiological monitoring in patients with decompression of the ulnar nerve near the elbow joint.

At the elbow, the ulnar nerve may be compressed either in the retrocondylar groove, in the cubital tunnel, or compressed by Osborne's band. Optimal surgical therapy should be directed at the specific site of involvement. It is more difficult to identify the level of ulnar nerve compression. Anatomical variations may make it difficult to identify the causes of ulnar neuropathy at the elbow. The data obtained by inspection, probing, or electroneurography do not allow one to reliably identify the compression level. Intraoperative electroneuromyography performed in conjunction with 14 ulnar nerve explorations helped localize the precise site of compression in 12 cases. Intraoperative studies helped identify compression by Osborne band in 8 patients. We conclude that intraoperative electroneuromyography identifies compression levels of ulnar neuropathy more accurately than the conventional examination methods do.