Results of the transition from posterolateral to anterior minimally invasive approach for total hip arthroplasty

BACKGROUND: The anterior minimally invasive (AMI) approach reduces soft tissue damage, risk of dislocation and enhances recovery, but it is associated with certain complications. The aim of this study is to compare the outcomes of patients who underwent total hip arthroplasty (THA) through posterolateral (PL) and AMI approaches performed by the same surgeon, in order to determine the learning curve associated with this new approach. METHODS: This retrospective cohort study included patients who underwent THA via PL and AMI approach between 2017 and 2022, with a minimum follow-up of 1 year. Hip fracture and oncologic patients were excluded. Demographic variables, functional scores and perioperative complications were assessed. A bivariate analysis was performed to identify differences between groups. RESULTS: Data of 124 AMI and 120 PL patients were analyzed. Demographic characteristics among groups were homogeneous. Functional outcomes at 3 months were superior for AMI (Oxford: 43 vs. 38; p < 0.05), no dislocations were identified (0% vs. 4.2%; p < 0.05) and no differences in the transfusion rate were found (6.5% AMI vs. 6.7% PL; p = 0.996). Infection rate was 4% for AMI and 3.4% for PL (p = 0.572). Surgical time was shorter for the PL approach, but the median surgical time of the last 25 AMI cases was shorter. CONCLUSIONS: The AMI approach is an excellent alternative for patients requiring THA. Although surgical time and perioperative bleeding were greater during the learning curve, this approach offers improved functional outcomes and a lower dislocation rate, without significant differences in transfusion and infection outcomes, demonstrating that responsible innovation and safe implementation of new techniques is possible.