Incidence and functional outcomes of malunion of nonoperatively treated humeral shaft fractures.

We conducted a study to determine the overall incidence and long-term clinical and functional outcomes of patients with malunion after nonoperative management of humeral shaft fractures. Fifteen patients with radiographic malunion (>20° angulation or shortening of :ge;2.5 cm) were identified, and their medical records retrospectively reviewed for information about their injuries and treatment. Long-term outcomes were assessed with a self-reported questionnaire, the DASH (Disabilities of the Arm, Shoulder, and Hand) form, and physical examination. Of 91 study-eligible patients, 15 (16%) had malunion after nonoperative management of humeral shaft fractures treated over an 11.5-year period. The 8 patients reached for long-term follow-up had a mean DASH score of 10.4. Seventy-five percent of patients reported having no functional limitations and being satisfied with the outcome of their treatment. However, 75% also reported a noticeable cosmetic deformity; for 25% of patients, this was a major reason for dissatisfaction. Our findings suggest that malunion may be more common than previously thought but, for a majority of patients, does not cause significant pain, functional limitations, or dissatisfaction. However, patients should be counseled about the high likelihood of cosmetic deformity, which they may find bothersome.