Comparison of Outcomes in Dual-Mobility Versus Fixed-Bearing Implants in Primary Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

Total hip arthroplasty (THA) is often regarded as one of the most successful surgical techniques developed in the twenty-first century. However, it is associated with complications such as prosthetic instability, dislocations, or infections. Dual-mobility (DM) implants have been developed with the goal of reducing the incidence of dislocations by increasing the femoral head-neck ratio, maximising hip stability, and improving the range of motion (ROM) before impingement and dislocation. This systematic review aims to comprehensively compare the safety and efficacy of DM versus fixed-bearing (FB) implants in primary THA patients. A comprehensive search strategy of PubMed, Embase, Scopus, and Web of Science Core Collection databases was executed to identify pertinent literature comparing DM and FB implants in THAs. Eligible studies underwent independent screening, and data were systematically extracted. The analysis employed pooled risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous variables, each accompanied by their respective 95% confidence intervals (CI). Our systematic review and meta-analysis included nine studies encompassing 22,277 patients. The DM group had a significantly reduced incidence of dislocations compared to the FB group (RR 0.25, 95%CI [0.13, 0.47]; p-value <0.0001) and a significantly shorter length of stay (MD -9.92, 95%CI [-15.53, -4.32]; p-value = 0.0005). The FB group, however, had a significantly shorter operative time compared to the DM group (MD 10.41, 95%CI [7.64, 13.17]; p-value < 0.00001). We did not identify any significant statistical differences between the DM and FB groups regarding patient-reported outcome measures, the incidence of all-cause readmissions, the incidence of periprosthetic fractures, the incidence of infections, or the incidence of groyne pain.