A propensity score-matched analysis on the impact of patient and surgical factors on early periprosthetic joint infection in minimally invasive anterolateral and transgluteal total hip arthroplasty

Introduction Increased risk of periprosthetic joint infection (PJI) in minimally invasive (MIS) total hip arthroplasty (THA) is still debated. This study aimed to identify differences in surgical and patient-related risk factors for PJI between an MIS anterolateral approach and transgluteal-modified Hardinge approach. Methods A retrospective cohort of 5315 THAs performed between 2006 and 2019 at a single institution was screened. Short stem THAs performed via an MIS anterolateral approach in the supine position and standard straight stem THAs performed via a transgluteal modified Hardinge approach were included. Propensity score matching was performed to control for selection bias. After matching, 1405 (34.3%) short stem THAs implanted via MIS anterolateral approach and 2687 (65.7%) straight stem THAs implanted via a transgluteal modified Hardinge approach were included. The risk of PJI due to patient-specific and surgical factors was retrospectively analyzed using chi-square test and multivariate regression analysis. Results PJI occurred in 1.1% in both MIS anterolateral and transgluteal approach ( p = 0.823). Multivariate regression showed an increased infection risk for patients with a BMI between 35 and 39.99 kg/m 2 (OR 6.696; CI 1.799–24.923; p = 0.005), which could not be demonstrated for transgluteal approach (OR 0.900; CI 0.900–4.144; p = 0.93). A BMI ≥ 40 kg/m 2 (OR 14.150; CI 2.416–82.879; p = 0.003) was detected as a risk factor for PJI only in anterolateral approach. Increased operation time ≥ 121 min showed a significantly increased risk for PJI in the general cohort (OR 6.989; CI1.286–37.972; p = 0.024). Conclusion Minimally invasive anterolateral and transgluteal THA show a comparable rate of early PJI within the first year of index surgery. A BMI of ≥ 35 kg/m 2 was detected as a clear risk factor for infection in the anterolateral approach. Prolonged operation time ≥ 121 min increases the risk of PJI regardless of approach.