Static scapholunate dissociation: A new reconstruction technique using a volar and dorsal approach in a cadaver model

We used 4 fresh-frozen cadaver arms to assess a method of reconstruction we designed for static scapholunate dissociation. The dorsal scapholunate lig ament, scapholunate interosseous ligament, radioscapholunate, and radioscap hocapitate ligaments were sectioned. Radiographs were taken before sectioni ng, after sectioning, and after reconstruction. Passive motion was also mea sured before sectioning and after the repair. The dorsal scapholunate ligam ent was repaired directly; the palmar radioscapholunate and radioscaphocapi tate ligaments were reconstructed using a free flexor carpi radialis tendon autograft and Mitek mini suture anchors (1.8-mm diameter and 5.4-mm length ; Mitek Products, Norwood, MA) for anatomic fixation. An independent board- certified hand surgeon analyzed the radiographs of the wrists taken before and after sectioning and after reconstruction. Assessment of the unsectione d wrists revealed an average scapholunate angle of 45 degrees. After scapho lunate dissociation was created the average scapholunate angle was 71 degre es. Repair of the dorsal scapholunate ligament alone did not improve the sc apholunate angle. Average scapholunate angle after repair of the dorsal sca pholunate ligament and reconstruction of the palmar ligaments was 43 degree s. Average range of motion on flexion, extension, and radial and ulnar devi ation before ligament sectioning and after reconstruction was unchanged at 54 degrees, 59 degrees, 19 degrees, and 40 degrees respectively. This techn ique shows an improvement in scapholunate angle on lateral radiographs, and passive motion remained relatively unchanged, Copyright (C) 2001 by the Am erican Society for Surgery of the Hand.