Background: Intra-articular malunion of the distal radius may be complicated with radiocarpal and radioulnar joint subluxation, which may result in joint stiffness and loss of function. Conventional corrective osteotomy emphasizes on the restoration of the articular step-off. However, little information is available concerning the restoration of a concentric functioning joint through osteotomy.
Methods: From 2002 to 2007, 12 patients with chronic intra-articular distal radius fractures were evaluated at an average follow-up of 33.6 months after repositioning osteotomy. The average time from initial injury to reconstructive operation was 11.3 months. The indication for osteotomy included dorsal or volar subluxation of the radiocarpal joint, distal radioulnar joint, or both in addition to articular incongruity. A preoperative computed tomography scan or rapid prototyping (RP) models were performed as part of the surgical planning. Operation was preceded by volar, dorsal, or both approaches. Repositioning osteotomy and internal fixation were also performed. Radiographic analysis and the Disability of Arm, Shoulder and Hand score were used for the outcome assessment.
Results: All osteotomy sites healed and all events of radiocarpal and radioulnar subluxation were corrected. The average correction was 13.8 degrees (palmar tilt of the radius) and 1.9 mm in ulnar variance. The mean Disability of Arm, Shoulder and Hand score improved from 64 to 18.
Discussion: Conventional corrective osteotomy via an extra-articular approach was favorably performed to correct an extra-articular malalignment or nascent intra-articular malunion. Problems of abnormal architecture after an intra-articular fracture of the radius are complicated with subluxation of carpus or distal radioulnar joint, which require repositioning via precise articular approach. Both reconstructed computed tomography images and rapid prototyping models are very useful tools in preoperative planning for intra-articular osteotomy. Simulated osteotomy and joint repositioning can be performed in solid models before commencement of actual operation.
Conclusion: Repositioning osteotomy consistently restores joint alignment and achieves functional improvement either in cases of nascent simple malunion or complex intra-articular malunion.