Clinical and Patient-Reported Outcomes of the SuperPath Versus Hardinge Approach in Total Hip Replacement for Osteoarthritis: A Retrospective Cohort Study

Background: There are various surgical approaches for total hip replacement (THR), such as the Direct Lateral (Hardinge), anterior, and supra-acetabular (SuperPath) approach. The aim of this study was to compare the post-operative clinical, functional and quality of life outcomes of the SuperPath and Direct Lateral approach in hip osteoarthritis patients undergoing THR. Methods: A retrospective analysis was performed of a single-surgeon consecutive cohort of THR's. Data was obtained from the St. Vincent's Melbourne Arthroplasty Outcomes (SMART) Registry, for all THR's between 01-01-2012 and 31-12-2019. Primary outcomes were the patient-reported WOMAC and VR12, measured at pre-op, 12- and 24-month timepoints. Groups were compared using a mixed-model analysis adjusted for potential confounders. Secondary outcomes were length of stay, surgery duration, complications, readmissions, and reoperations. Results: 384 patients were analysed (259 Direct Lateral; 125 SuperPath). Total WOMAC Scores were significantly better for the SuperPath group (mean diff: 7.1, 95% CI 0.76–13.54, p = 0.02). VR12 Total Scores were significantly higher for SuperPath patients (mean diff: 3.9, 95% CI 0.53–7.35, p = 0.02). For secondary outcomes, the SuperPath approach had a shorter operation time than the Direct Lateral approach (81.9 min vs. 85.8 min, mean difference 3.8, 95% CI: 0.14–7.50, p = 0.04). Conclusion: Although the SuperPath approach led to slightly better pain, function and quality of life outcomes than the Direct Lateral approach, the difference was below the minimal clinically important difference (MCID) although statistically significant. There were no differences in other clinical outcomes except for shorter surgery duration, presumably since there were more cemented procedures in the Direct Lateral group.