Isolated ulnar shortening osteotomy for the treatment of extra-articular distal radius malunion

Purpose: To report the clinical outcomes and complications for a cohort of patients who had extra-articular distal radius malunions treated with isolated ulnar-shortening osteotomy (USO). A second purpose was to define the dorsal angulation limit that would still result in clinical and functional improvement after isolated USO for distal radius malunion. We postulated that patients with up to 20° dorsal or volar tilt could be successfully treated with isolated USO. Methods: We conducted a retrospective chart review for all patients who had an isolated USO for the treatment of ulnar impaction syndrome after distal radius malunion between January 1990 and December 2011. A total of 18 patients underwent isolated USO after distal radius malunion. The mean age of the patients was 53 years and the mean duration of follow-up was 34 months. We used Wilcoxon signed-rank tests to compare preoperative and postoperative range of motion; pain; Quick Disabilities of the Arm, Shoulder, and Hand scores; and radiographic measurements. Results: Average intraoperative ulna shortening was 5.6 mm. Average flexion-extension arc improved from 79° preoperatively to 105° postoperatively. Average pronation-supination arc improved from 121° preoperatively to 162° postoperatively. Average visual analog scale pain score improved from 4.1 to 1.9. Average Quick Disabilities of the Arm, Shoulder, and Hand score improved from 43 to 11. Conclusions: This case series demonstrated a significant improvement in pain score and range of motion after isolated USO for distal radius malunion. Patients with up to 20° dorsal tilt and radial inclination as low as 2° demonstrated improved clinical and functional outcomes after isolated USO. Given the comparable functional outcomes with shorter operative times and lower complication rate requiring fewer secondary surgeries, isolated USO is an attractive alternative to distal radius osteotomy for the management of distal radius malunion in patients with up to 20° dorsal tilt. Type of study/level of evidence: Therapeutic IV.