PAPER 023: A RANDOMIZED TRIAL OF REAMED VERSUS NON-REAMED INTRAMEDULLARY NAIL INSERTION ON RATES OF RE-OPERATION IN PATIENTS WITH FRACTURES OF THE TIBIA

Abstract

Purpose: Surgeons agree on the benefits of intramedullary nailing of tibial shaft fractures. The SPRINT primary objective aimed to assess the impact of reamed versus unreamed intramedullary nailing on rates of re-operation in patients with tibial shaft fractures.

Method: The Study to Prospectively Evaluate Reamed Intramedullary Nails in Tibial Fractures (SPRINT) was a multi-centre, randomized trial including 29 clinical sites. SPRINT enrolled 1319 patients with open or closed tibial shaft fractures. Patients, outcome assessors, and data analysts were blinded to treatment allocation. Peri-operative care was standardized, and re-operations before 6 months were not permitted unless there was critical bone loss. Patients received a statically locked intramedullary nail with either reamed or unreamed insertion. The primary outcome was re-operation to promote healing, treat infection, or preserve the limb. We planned a priori to conduct a subgroup analysis of outcomes in patients with open and closed fractures. Our sample size calculations required 1200 patients followed for 1 year.

Results: Of 1319 enrolled patients, 1226 patients were followed to 1 year. Across treatment groups, patients did not differ in age, gender and closed and open fracture types (I-IIIB). The overall event rate was 17.8% (13.7% closed, 26.5%, open fractures). A significant subgroup interaction effect in patients with open versus closed fractures (p=0.01) mandated a separate analysis for each subgroup. In 826 patients with closed fractures, patients with a reamed nail had a relative risk reduction of 33% (95%CI: 4–53%, P=0.03). This treatment effect was largely driven by differential autodynamization rates (rel. risk: 0.42, p=0.01). Among 400 patients with open fractures, there was a trend towards an increased risk of an event (rel. risk=1.27, p=0.16) for those who received a reamed nail.

Conclusion: Our overall incidence of revision surgery was lower than reported in previous studies. Possible reasons for the overall lower event rates in SPRINT are:

1. standardization of surgical and post-surgical care resulted in superior care among the SPRINT centres and surgeons and

2. proscription of surgery until after 6 months. Optimizing peri-operative care and avoiding premature re-operation may substantially decrease the need for re-operation in tibial fracture patients.