Anatomic relationships of an endoscopic carpal tunnel device to surrounding structures.

Anatomic relationships of an endoscopic carpal tunnel device to surrounding soft tissue structures along the ring finger and the long-ring interspace axis were investigated in 28 adult cadaver hands. The average distance from the center of the device to the median nerve in the carpal tunnel averaged 3.3 mm in the ring finger axis and 2.5 mm in the long-ring interspace axis. The average distance from the distal edge of the transverse carpal ligament to the superficial palmar arch was 4.8 mm in the ring finger axis and 5.5 mm in the long-ring interspace axis. These and other more subtle anatomic observations indicate the greater safety of using the ring finger axis for endoscopic carpal tunnel release.