Management of chronic rotary subluxation of the scaphoid by scapho-trapezio-trapezoid arthrodesis. Rationale for the technique, postoperative changes in biomechanics, and results.

In cases of static or symptomatic dynamic scapholunate instability, reduction of the scaphoid proximal pole into the scaphoid fossa of the radius and stabilization of the relationship of the scaphoid and lunate by distal arthrodesis to the trapezium and trapezoid will significantly alter carpal mechanics; however, elimination of pain, preservation of a functional arc of motion, and restoration of the ability to pursue routine activities (including heavy labor) all suggest that the planes of radiocarpal and intercarpal motion following distal scaphoid arthrodesis are compatible with long-term physiologic function without late loss of reduction.