Twenty-six of 27 patients in whom an ulnar shortening osteotomy had been performed to treat ulnar impaction following distal radius (20 patients) or forearm (6 patients) fractures were evaluated at an average follow-up of 21 months. All but 3 patients were satisfied with the end-result and according to a modified Gartland-Werley score there were 1 excellent, 10 good, 10 fair and 5 poor results. This is distinctly inferior to other reports of mainly non-traumatic indications. Degenerative changes at the distal radioulnar joint were associated with fair and poor results and careful radiological examination of this joint is mandatory before ulnar shortening is performed in posttraumatic ulnar impaction syndrome. Bony union of the osteotomy was achieved at 12 to 16 weeks postoperatively except for 2 cases and there was no difference between transverse (13 cases) and oblique osteotomies (13 cases). We therefore prefer the technically easier transverse osteotomy and recommend the use of 3.5 dynamic compression plates for stabilisation which resulted in a low complication rate in our series and enables early active wrist mobilisation.