The Impact of Surgical Approach on 90-Day Prosthetic Joint Infection After Total Hip Replacement - A Population-Based, Propensity Score-Matched Cohort Study.

Background: Prosthetic joint infection (PJI) is a devastating complication of total hip arthroplasty (THA). This study aimed to determine if the anterior approach (AP) influenced the incidence of early PJI in THA compared to posterior approach (PP).

Methods: Record linkage was performed between state-wide hospitalization data and a national joint replacement registry to identify unilateral THA performed via the AP or PP. Complete data on 12,605 AP and 25,569 PP THAs were obtained. Propensity score matching (PSM) was undertaken to match covariates between the approaches. Outcomes were the 90-day PJI hospital readmission rate(using narrow and broad definitions) and 90-day PJI revision rate (defined as component removal or exchange).

Results: The raw PJI readmission rate for AP was lower than PP (0.8% versus 1.1%, respectively). In the PSM analysis, there was no statistically significant difference in PJI readmission rate between approaches using narrow or broad definition of PJI readmission. In terms of revision for infection, both methods showed AP had a significantly lower rate than PP, with an adjusted odds ratio (OR) of 0.47 (95% confidence interval (CI) 0.30, 0.75) for the 1:1 nearest neighbor method and 0.50 (95% CI 0.32, 0.77) for the subclassification method.

Conclusion: After addressing known confounders, there was no significant difference in the 90-day hospital readmission rate for hip PJI between approaches. There was a significantly reduced 90-day PJI revision rate for AP. The difference in revision may reflect differences in the surgical management of PJI between hip approaches rather than a difference in the underlying rate of infection.