INTERNAL-FIXATION OF PILON FRACTURES OF THE DISTAL RADIUS

When closed manipulation fails to restore articular congruity in commi nuted, displaced fractures of the distal radius, open reduction and in ternal fixation is required. Results of surgical stabilization and art icular reconstruction of these injuries are reviewed in this retrospec tive study of 49 patients with 52 displaced, intra-articular distal ra dius fractures. Forty-three patients (87%) with a mean age of 37 years (range of 17 to 79 years) were available for evaluation. The mean fol low-up time was 38 months (range 22-69 months) When rated according to the Association for the Study of Internal Fixation (ASIF), 19 were ty pe C2 and 21 were type C3. We devised an Injury Score System based on the initial injury radiographs to classify severely comminuted intra-a rticular fractures and to identify those associated with carpal injury (3 patients). Post-operative fracture alignment, articular congruity, and radial length were significantly improved following surgery (p <. 01) Grip strength averaged 69% +/- 22% of the contralateral side, and the range of motion averaged 75% +/- 18% of the contralateral side pos t-operatively. A combined outcome rating system that included grip str ength, range of motion and pain relief averaged 76% +/- 19% of the con tralateral side. There was a statistically significant decrease in the combined rating with more severe fracture patterns as defined by the ASIF system (p <.01), Malone classification (p <.03), and the Injury S core System (p <.001). The Injury Score System presented here, and in particular the number of fracture fragments, correlated most closely w ith outcome of all the classification systems studied. Operative treat ment of these distal radius fractures with reconstruction of the artic ular congruity and correction of the articular surface alignment with internal fixation and/or external fixation, can significantly improve the radiographic alignment and functional outcome. Furthermore, the de gree to which articular stepoff, gap between fragments, and radial sho rtening are improved by surgery is strongly correlated with improved o utcome, even when the results are corrected for severity of initial in jury, whereas correction of radial tilt or dorsal tilt did not correla te with improved outcome.