Arthroscopic Reduction-Association of the Scapholunate

Abstract

The reduction-association scapholunate (RASL) procedure for stabilization of the scapholunate joint is an alternative to soft-tissue procedures that do not maintain normal carpal alignment, despite reports of good symptomatic relief. The RASL procedure—indicated for patients with scapholunate instability or scapholunate dissociation without arthritis and, in selected cases, with stage 1 scapholunate advanced collapse of the wrist—can be performed arthroscopically. Radial midcarpal and 3-4 radiocarpal portals are used to excoriate and prepare the scapholunate joint surfaces. By use of 0.62″ K-wire joysticks in the lunate and distal pole of the scaphoid, the scaphoid undergoes dorsiflexion and supination while the lunate undergoes palmarflexion to achieve reduction. A .35″ guidewire is advanced through the scaphoid waist, across the scapholunate joint to the proximomedial corner of the lunate. Supplemental K-wire fixation, from the scaphoid to the capitatum and lunate to the radius, stabilizes the reduction for placement of a cannulated HBS screw (Orthosurgical Implants, Miami, FL) through a 1-2 portal, while reduction and positioning are confirmed arthroscopically. Arthroscopy facilitates anatomic reduction of the joint, as well as the critically important, precise placement of the cannulated HBS screw, by use of 3 portals rather than the traditional 2-incision approach.