Rita M. Patterson, Laura Williams, Clark R. Andersen, Shukuki Koh and Steven F. Viegas
The purpose of this study was to investigate the effect of experimental control mechanisms, simulated active (tendon-driven) and passive (externally assisted), on carpal motion. Kinematics of the carpal bones in five fresh-frozen cadaver upper extremities were studied using an optical motion analysis system. There were no significant differences in carpal motion (flexion-extension motion or radial-ulnar deviation) when the wrist was moved in simulated active motion through the extensor and flexor tendons or in passive motion, with a constant force applied to the tendons. Kinematics for simulated active motion, in general, was more difficult to control and was less smooth than the kinematics for passive motion. The authors conclude that carpal bone kinematics (excluding the pisiform) in a healthy normal joint are similar in both simulated active (tendon-driven) and passive (externally assisted) wrist motion because the carpal bones are passively moved during wrist motion (there are no direct tendon-to-muscle attachments to the proximal carpal bones and minimal attachments to the distal carpal bones).
The Journal of Hand Surgery, 2007, 32(7),