The effects of scaphoid intercarpal stabilizations on wrist mechanics: an experimental study

A fresh cadaver study of the effects of a variety of scaphoid stabilizations on wrist motions is reported. Scaphoid-trapezium-trapezoid stabilizations with the scaphoid in its normal anatomic position and the same stabilizations with the scaphoid in malposition, either vertical or horizontal in relation to the radius, were compared. Scaphoid-capitate stabilizations with the scaphoid in its normal position were also studied. With the scaphoid vertical, a scaphoid-trapezium-trapezoid stabilization resulted in greater loss of wrist flexion and ulnar deviation whereas, with the scaphoid horizontal, wrist extension and radial deviation were more severely affected than when the scaphoid was stabilized in its normal position. With the scaphoid in its anatomic position, both scaphoid-trapezium-trapezoid and scaphoid-capitate stabilizations resulted in similar patterns of wrist motion.