Outcome following Acute Primary Distal Ulna Resection for Comminuted Distal Ulna Fractures at the Time of Operative Fixation of Unstable Fractures of the Distal Radius

Abstract

Optimal acute management of the highly comminuted distal ulna head/neck fracture sustained in conjunction with an unstable distal radius fracture requiring operative fixation is not well established. The purpose of the present study was to determine the clinical, radiographic, and functional outcomes following acute primary distal ulna resection for comminuted distal ulna fractures performed in conjunction with the operative fixation of unstable distal radius fractures. Between 2000 and 2007, 11 consecutive patients, mean age 62 years (range, 30–75) were treated for concomitant closed, comminuted, unstable fractures of the distal radius and ulna metaphysis. All 11 patients underwent distal ulna resection through a separate dorsal ulnar incision with ECU tenodesis following surgical fixation of the distal radius fracture. According to the Q modifier of the Comprehensive Classification of Fractures, there were six comminuted fractures of the ulnar neck (Q3) and five fractures of the head/neck (Q5). Operative fixation of the distal radius fracture included volar plate fixation in four patients and spanning external fixation with supplemental percutaneous Kirschner wires in seven patients. At a mean of 42 months (range, 18–61 months) postoperatively, clinical, radiographic, and wrist-specific functional outcome with the modified Gartland and Werley wrist score were evaluated. At latest follow-up, mean wrist range of motion measured 53° flexion (range, 35–60°), 52° extension (range, 30–60°), 81° pronation (range, 75–85°), and 77° supination (range, 70–85°). Mean grip strength measured 90% of the contralateral, uninjured extremity (range, 50–133%). No patient had distal ulna instability. Final radiographic assessment demonstrated restoration of distal radius articular alignment. According to the system of Gartland and Werley as modified by Sarmiento, there were seven excellent and four good results. No patient has required a secondary surgical procedure. Acute primary distal ulna resection yields satisfactory clinical, radiographic, and functional results in appropriately selected patients and represents a reliable alternative to open reduction and internal fixation when anatomic restoration of the distal ulna/sigmoid notch cannot be achieved. Primary distal ulna resection with distal radius fracture fixation may help avoid secondary procedures related to distal ulna fixation or symptomatic post-traumatic distal radioulnar joint arthrosis.