Purpose: We evaluated submuscular anterior transposition of the ulnar nerve at the elbow with lengthening of the medial epicondylars as described by Dellon in patients with ulnar nerf deficiency due to compression.

Material and methods: A consecutive series of 30 submuscular tranpositions of the ulnar nerve in 28 patients were performed between 1994 and 1998. Four patients had had a prior procedure (two simple neurolyses, two subcutaneous transpositions). Mean age was 52 years. Preoperative EMB confirmed the diagnosis of ulnar compression at the elbow. All patients has sensorial and/or motor deficits. Postoperative immobilisation was maintained for 15 to 20 days.

Results: The patients were reviewed at a mean follow-up of four years two months. There were no cases of paraesthesia. Improved sensorial function was observed in 71% of the cases (normalisation in 50%) with improvement in the Foment sign and grip in 81.5% (normalisation in 48%). Mean elbow extension was −5°, and flexion was 135°. There was not limitation on wrist amplitudes. The thumb finger force on the operated side was 78% to 94% that measured on the healthy side and was a function of the MacGowan grade. The palm-finger force was 80% to 95% of the healthy side. There has been no recurrence at last follow-up.

Conclusion: Submuscular transposition using the Dellon technique in 30 cases of ulnar nerve compression at the elbow in patients with ulnar deficiency provided satisfactory sensorial and motor recovery. The usefulness of lengthening the medial epicondyls lies in removing the tension on the ulnar nerve and the little effect on elbow and wrist mobility. Submuscular transposition is the technique of choice for repeated neurolysis.