Outcome analysis of ulnar shortening osteotomy for ulnar impaction syndrome.

BACKGROUND: Ulnar-sided wrist pain is a common problem in the upper extremity. It affects a broad patient population and can be difficult to treat. Ulnar impaction syndrome (UIS) is major cause of ulnar-sided wrist pain and a number of different operations have been used to correct it, including ulnar shortening osteotomy (USO).

OBJECTIVE: To retrospectively review functional outcomes and complication rates of USO for UIS at the Hand and Upper Limb Centre (London, Ontario) over a two-year period.

METHODS: Twenty-eight patients who underwent USO between 2007 and 2009 participated in the present study. Ulnar variance pre- and post-surgery was assessed using standard radiographic examination. Patient-rated outcomes were measured using a visual analogue scale (VAS) for pain and the Disabilities of the Arm, Shoulder and Hand (DASH) survey for functional outcomes. Objective grip strength and range of motion were compared with the contralateral extremity.

RESULTS: On average, USO achieved a 3.11 mm reduction in ulnar variance. Nonunion occurred in five patients and required a secondary bone grafting procedure. All USO eventually healed. Overall, pain improved by 47.2% and the mean DASH score after surgery was 37.21. Flexion, extension and supination range of motion decreased by 10° compared with the unaffected side. Eleven patients (39%) elected to undergo a second surgery for hardware removal. Patients receiving compensation from the Workplace Safety and Insurance Board experienced significantly higher residual pain (VSA 5.24 versus 1.97) and disability levels (DASH 60.23 versus 25.70). Smokers also experienced worse outcomes in terms of pain (VSA 4.43 versus 2.36) and disability (DASH 51.06 versus 29.67). In this cohort, smoking was not associated with a higher rate of nonunion.

CONCLUSION: USO is effective in reducing pain in UIS and improves disability, at the price of a small decrease in range of motion. Smokers and people receiving compensation from the Workplace Safety and Insurance Board, however, have significantly worse subjective outcomes (VAS and DASH), but similar objective outcomes (range of motion).