Rates of union and risk factors for continued nonunion following exchange nailing of tibial nonunion

INTRODUCTION: The objective of this study was to evaluate the rate of nonunion repair success in tibia nonunions treated with exchange nailing. This retrospective cohort study was conducted across five academic Level 1 trauma centers and included 63 patients with tibia nonunions. MATERIALS AND METHODS: Patients who sustained a tibia fracture (AO/OTA 42) treated with intramedullary fixation that developed a nonunion and were subsequently treated with exchange nailing were retrospectively reviewed. The primary outcome measure was nonunion repair success based on osseous union. Additional analyses included union rate by AO/OTA classification, nonunion type, implant(s) used, graft used, time from initial procedure, and infection status. RESULTS: All patients sustained an AO/OTA type 42 fracture. Out of 63 patients, 47 tibias (75%) achieved osseous union after the index exchange nail procedure. The rates of nonunion revision success were similar across nonunion types and time from initial procedure until exchange nailing. There was no significant difference in union rate when infection was present. Complications included re-operation, readmission, infection, and implant failure. CONCLUSIONS: This large, multicenter study with contemporary implants, instruments, and techniques for exchange nailing tibia nonunions demonstrates a nonunion repair success rate of 75%, consistent with the lower end of reported data in previous literature. No identifiable risk factors for failure of exchange nailing in tibia nonunions were found. LEVEL OF EVIDENCE: Level III Evidence.