EVALUATION OF RECONSTRUCTIONS OF THE UNSTABLE DISTAL ULNA

Abstract

Because the distal radioulnar joint (DRUJ) is a weight-bearing joint, surgical procedures treating DRUJ instability must be evaluated accordingly. Biomechanically, such procedures can be viewed from two approaches: One that preserves DRUJ biomechanics, which includes Groups A (intracapsular anatomical reconstruction) and B (ulnar shortening alone); and another that radically alters DRUJ biomechanics, which includes Groups C (tendon sling) and D (resection of ulnar head). This study compared the results of these two approaches. Sixty-four patients having DRUJ surgery between 1984 and 1993 met the inclusion criteria of painful dorsal dynamic DRUJ instability, no DRUJ arthrosis, and no ulnocarpal impingement. However, only 25 returned for follow-up examination (Group A, 14 patients; B, 3; C, 2; D, 6). Grip strength, instability, pain, ROM, and satisfaction were scored. The total scores of Groups A and B combined were significantly better than those of Groups C and D combined. Scores for pain with lifting weight and for instability in the combined Groups A and B were significantly better than those in the combined Groups C and D. Although the number of patients who returned for follow-up was small, the significantly better scores achieved by the groups whose procedures preserved DRUJ biomechanics (anatomical reconstruction or ulnar shortening), indicate that these procedures may be the treatment of choice over the techniques that radically alter the DRUJ biomechanics (tendon slings or ulnar head resection).