[Electrophysiological evaluation of level compression in elbow ulnar neuropathy]

In order to establish the focal compression in the elbow, a study of 318 patients with clinical manifestations of ulnar neuropathy was carried out. We divided the patients in three groups: I) those who presented mechanical anomalies with background of fracture, elbow valgus...; II) those who did not present mechanical anomalies, but they have been in bed long time or they have been operated...; III) those who did not have evident cause for the compression.

Antidromic sensory conduction and segmentary motor conduction of the ulnar nerve were studied, and segmental motor conduction along the elbow with interval of 2 centimetres (technique of Kanakamedala).

83.6% of the 318 ulnar neuropathy had the focal compression in the ulnar sulcus. 8.2% had the focal compression distal to the ulnar sulcus. 0.94% had double focal compression. In 7.2% was not possible to determinate the focal compression. In group I, the focal compression was in the ulnar sulcus in 93.8% of the cases. In group II, the focal compression was in the ulnar sulcus in 94.3% of the cases. In group III, the focal compression was in the ulnar sulcus in 55.8% of the cases, and distal to the ulnar sulcus in 29.1% of the cases.

It is possible to localize the focal compression of the ulnar neuropathy in the elbow, with high level of probability, with the nerve conductions. This allows the surgeon to be orientated about therapeutical attitude.