Bilateral anomalous course of the ulnar nerve at the wrist causing ulnar and median nerve compression syndrome. Case report.

The case of a patient with a bilateral compression syndrome of the ulnar and median nerves at the wrist is described. Both ulnar nerves, which were surgically explored at different times, followed an anomalous course and passed into the canalis carpi side by side with the median nerve. This variation in the course of the ulnar nerve is extremely rare and causes a unique syndrome with characteristic electromyographic patterns.