Objectives To identify factors associated with the need for reoperations in patients treated surgically for fracture nonunion. Design Retrospective cohort study. Setting One urban Level 1 trauma center and an orthopaedic specialty hospital. Patients/participants This study included 365 patients who did not and 95 patients who did undergo a reoperation after nonunion repair. Intervention All patients who underwent fracture nonunion repair were identified. Baseline demographic, injury, and surgical information were collected. These factors were compared between patients who did and did not require an unplanned reoperation. Main outcome measurements An unplanned reoperation after index fracture nonunion surgery. Results When compared with patients who did not undergo a reoperation after their index fracture nonunion surgery, patients who underwent at least 1 reoperation had a greater proportion of those who sustained an open fracture, a high-energy injury, initial neurologic or vascular injuries, the need for a flap or soft tissue graft at initial treatment, and lower extremity injuries with univariate analysis. Unplanned reoperation was also associated with diagnosis of "infected" nonunion at initial nonunion surgery. Multivariate analysis confirmed initial nerve or vascular injuries and positive infection status were statistically significant predictors of a reoperation. Conclusions Initial injury characteristics such as nerve or vascular injury at initial injury and positive infection status at the index nonunion surgery were associated with the need for a secondary surgery after nonunion repair. Appropriate care of these patients should be aimed at adjusting expectations of unplanned reoperation in the future and potentially enhanced treatment strategies. Level of evidence Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
