Outcomes following distal humeral fracture fixation with an extensor mechanism-on approach.

Abstract

Distal humeral fractures have traditionally been managed with surgical approaches that disrupt the extensor mechanism. We hypothesized that an extensor mechanism-on approach for operative fixation of distal humeral fractures with parallel or orthogonal plate constructs would allow excellent healing, a motion arc of the elbow exceeding 100°, and maintenance of extensor mechanism strength. Distal humeral open reduction and internal fixation (ORIF) was performed with either orthogonal or parallel plate constructs in seventy-nine elbows. Thirty-seven elbows were fixed via an extensor mechanism-on surgical approach, and twenty-four of them were available for additional evaluation. Radiographs as well as MEPI (Mayo Elbow Performance Index), DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores were obtained. All thirty-seven fractures healed primarily. Three elbows underwent later release because of stiffness. The median arc of elbow motion was 126° (range, 60° to 141°). The mean MEPI was 91.5 points and the mean DASH score was 15.9 points, indicating excellent scores with mild impairment. The median percent loss of triceps strength was 10% (range, 0% to 49%) compared with the contralateral, normal elbow. Open treatment of distal humeral fractures with an extensor mechanism-on approach results in excellent healing, a mean elbow flexion-extension arc exceeding 100°, and maintenance of 90% of elbow extension strength compared with that of the contralateral, normal elbow.