A potential complication of endoscopic carpal tunnel release.

Complications of carpal tunnel release have been well documented in the literature. Recently, a procedure for endoscopic release of the transverse carpal ligament has been described. This case report demonstrates a potential complication of endoscopic carpal tunnel release, in which the flexor digitorum superficialis tendon to the ring finger was nearly cut when the arthroscopic trocar passed beneath it. The procedure was converted to an open carpal tunnel release when the transverse fibers of the carpal ligament were not seen after several passes of the trocar. This complication was related to the inability to fully extend the wrist and metacarpophalangeal joints because of arthritic contractures. This case underscores the need for accurate identification of endoscopic anatomy prior to release of the carpal tunnel. The surgeon should not hesitate to convert to open technique if it becomes necessary.