Congenital carpal tunnel syndrome: case report of autosomal dominant inheritance and review of the literature.

Carpal tunnel syndrome (CTS) is unusual in childhood, and familial occurrence has been reported infrequently. A case of CTS in a seven-year-old boy, associated with abnormal thickening of the transverse carpal ligament and aplasia of the median nerve distal to this ligament, is described. Clinical, electrodiagnostic, and surgical findings are presented: all were consistent with absence of the median nerve distal to the transverse carpal ligament. Family history of CTS was positive in a pattern consistent with autosomal dominant transmission in three generations. Thickening of the transverse carpal ligament has been described, although infrequently, in childhood and familial CTS. Aplasia of the median nerve distally has not been reported in association with this anatomic abnormality. Case reports of familial CTS are reviewed, and other congenital anomalies which should be considered in the differential diagnosis of CTS in children and adults are discussed.