Corticosteroid Injection up to 8 Weeks Before Anterior Cruciate Ligament Reconstruction Doubles the Incidence of Postoperative Infection

Purpose: To determine whether at least 1 corticosteroid injection (CSI) within 8 weeks before anterior cruciate ligament reconstruction (ACLR) increases the incidence of postoperative infection. Methods: A large globally federated research database (TriNetX) containing more than 200 million patient records was queried retrospectively for patients undergoing ACLR between October 1, 2010, and January 1, 2024, using diagnosis and procedure codes. A cohort of patients receiving CSI up to 8 weeks before ACLR were compared with a cohort of patients who did not receive a CSI before ACLR. One-to-one propensity score matching was performed on the basis of preoperative characteristics and comorbid diagnoses. Outcomes examined were incidence of postoperative infection at 90 days and 180 days. Postoperative infection was defined as a formal infection diagnosis or need for a washout surgery. Comparisons were performed using Pearson χ² tests. Results: After matching, 2,439 patients were analyzed in each cohort with matched preoperative characteristics and comorbid diagnoses. Patients receiving a CSI in the 8 weeks before ACLR had a 90-day infection rate of 1.2% (30/2,439) compared with a control group infection rate of 0.6% (14/2,439) represented as an odds ratio of 2.1 (95% confidence interval 1.1-4.0, P = .015). After 180 days, the infection rates grew to 1.3% (33/2,439) for patients receiving CSI and 0.6% (15/2,439) for the control group with an odds ratio of 2.2 (95% confidence interval 1.2-4.1, P = .009). Conclusions: CSIs given within 8 weeks of ACL-R approximately double the incidence of postoperative infection. Level of Evidence: Level III, retrospective cohort study.