Scaphoid kinematic behavior after division of the transverse carpal ligament.

Abstract

The effect that carpal tunnel release (CTR) has on scaphoid motion has not been reported. Accordingly the purpose of this study was to determine the flexion/extension behavior of the scaphoid during global wrist radial/ulnar deviation before and after division of the transverse carpal ligament (TCL). In this study we examined the in vitro kinematics of the scaphoid during wrist deviation in 6 cadaver forearms both before and after the division of the TCL using a computerized camera monitoring system. The specimens were evaluated in 13 different positions, from 20 degrees of radial deviation to 40 degrees of ulnar deviation at increments of 5 degrees. The data indicate that the difference in scaphoid position after TCL division is statistically significant when the wrist is in ulnar deviation of 15 degrees or greater. In addition a significant difference in scaphoid extension between pre- and post-TCL division conditions was found at 5 degrees of radial deviation as well as at 5 degrees or more of ulnar deviation and increased with increasing ulnar deviation. Scaphoid kinematics are altered considerably in radial-ulnar deviation after division of the TCL. This alteration may have long-term consequences and contribute to commonly seen post-CTR symptoms.