Early Flap Reconstruction and Infection Rates in Open Lower Extremity Fractures: A Systematic Review and Meta-analysis.

Background: Severe open lower extremity fractures often require soft tissue reconstruction with a flap. Infection is a common complication of lower extremity flap coverage and is associated with prolonged hospitalization, high costs, and poor patient-reported outcomes. Elapsed time from injury to flap coverage can increase infection risk, but the optimal timing threshold remains debatable. We aimed to synthesize the literature and determine if time to flap is associated with reduced infection rates following traumatic lower extremity injuries. Methods: We searched 5 databases for articles published before March 2023. We included studies of 10 or more patients undergoing flap reconstruction for open lower extremity fractures. We extracted data on patient demographics, operative details, and postoperative complications and grouped individual data by time-to-flap: 72 hours or less versus more than 72 hours and 7 days or less versus more than 7 days. We performed meta-analyses at a significance level of α equal to 0.05. Results: Sixteen studies of 973 patients (986 extremities) were included. Reconstruction within 72 hours of injury was associated with a 52% reduction in infection (risk ratio [RR] 0.48 [95% confidence interval (CI) 0.25-0.89]) and a 41% reduction in all complications (RR 0.59 [95% CI 0.36-0.99]). Reconstruction within 7 days of injury was associated with a 50% reduction in infection (RR 0.50 [95% CI 0.31-0.82]) but no significant reduction in total complications (RR 0.57 [95% CI 0.28-1.15]). Conclusions: Flap coverage within 72 hours of injury reduces infection risk in patients undergoing lower extremity reconstruction for open fractures.