Iatrogenic Radial Nerve Palsy After Humeral Shaft Nonunion Repair: More Common Than You Think.

OBJECTIVES To determine the rate of iatrogenic radial nerve palsy (RNP) after surgical repair of established humeral shaft nonunion (HSNU). DESIGN Retrospective chart review. SETTING Level I trauma center. PATIENTS/PARTICIPANTS Fifty-four patients with HSNU, 10 (18.5%) of whom developed an iatrogenic RNP after nonunion repair. INTERVENTION HSNU repair with compression plate stabilization with or without autogenous bone graft. MAIN OUTCOME MEASUREMENTS Postoperative iatrogenic RNP. RESULTS Ten (18.5%) patients developed iatrogenic radial nerve palsies: 8 experienced complete resolution (mean, 2.5 months) and 2 experienced partial resolution. There were no statistically significant differences between patients who developed nerve palsy and those who did not in regard to age, gender, tobacco use, diabetic status, previous RNP, initial management (operative vs. nonoperative), surgical approach, presence of infected nonunion, number of previous surgeries, or operative time (P > 0.05). CONCLUSIONS The occurrence of iatrogenic RNP for patients undergoing surgical repair of an HSNU was 18.5%. According to historical data, this rate is nearly 3 times higher than for those undergoing open reduction and internal fixation of either acute humeral shaft fractures or HSNUs. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of Levels of Evidence.