The results of transposition of the ulnar nerve for traumatic ulnar neuritis.

Recent reports on the etiology, diagnosis and treatment of traumatic ulnar neuritis and tardy paralysis of the ulnar nerve have been published by Richards (1945) and by Gay and Love (1947). The present report is based on a detailed analysis of the results of transposition in forty-six cases with post-operative observation varying from one to five years. A further six cases of technically faulty transposition are discussed. Clinical material-Between 1941 and 1946 forty-six patients were admitted to the Peripheral Nerve Injuries Unit with “ traumatic ulnar neuritis.” This term, which is not wholly satisfactory, was used to embrace those cases in which a progressive lesion involved the ulnar nerve behind the medial epicondyle. Direct irritation from friction in a roughened groove, inadequate protection from repeated mild trauma, and stretching of the nerve trunk were the main exciting causes. The identification of the site of the nerve lesion was straightforward in most cases. In traumatic ulnar neuritis, however, there is a tendency for the interossei to be affected with sparing of the proximal muscles, and the slight blunting of sensibility may be difficult to detect. The clinical picture may therefore be confused with that produced by compression of the deep branch of the ulnar nerve in the palm, an uncommon condition described by Harris in 1929 and again by Russell and Whitty in 1947. The cases were classified as follows: post-traumatic or tardy ulnar palsy, 21 cases; arthritis of the elbow joint with no history of fracture, 10 cases; recurrent dislocation of the ulnar nerve, 3 cases; congenital cubitus valgus, 2 cases; local scarring, 3 cases; etiology doubtful, 7 cases. The severity of the lesions varied considerably and was independent of the etiology. In order to assess the benefit derived from operation, the cases have been graded according to the severity of the nerve involvement at the time of operation: Grade I Minimal lesions, with no detectable motor weakness of the hand. Grade II Intermediate lesions. Grade 111-Severe lesions, with paralysis of one or more of the ulnar intrinsic muscles.