Outcomes of Dual Mobility Versus Fixed-Bearing Components in Revision Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

Dual mobility (DM) implants have received increasing interest in revision surgery due to their increased stability. The aim of this systematic review was to compare outcomes of DM versus conventional fixed-bearing (FB) implants in revision total hip arthroplasty (rTHA). A comprehensive search was performed using the PubMed, Embase, and MEDLINE databases between January 2000 and 2023. Outcome measures included rerevision due to dislocation, rerevision for other causes, all-cause rerevision, total complication rate, and functional outcome measures. The Methodological Index for Nonrandomized Studies assessment tool was used to evaluate methodological quality and the risk of bias. A pooled meta-analysis was conducted, with an assessment of heterogeneity using the Chi-square and Higgins I2 tests. A further subgroup analysis was performed between DM implants and larger femoral head (> 36 mm) FB implants. A total of 13 studies met the final inclusion criteria, with an overall number of 5,004 rTHA hips included (2,108 DM and 2,896 FB). The DM implants had significantly lower odds of rerevision due to dislocation (odds ratio [OR] 0.38, P < 0.001), aseptic loosening (OR 0.54, P = 0.004), and all-cause rerevision (OR 0.55, P < 0.001) compared to FB implants. No statistically significant difference was seen in the odds of rerevision due to periprosthetic joint infection (OR 0.99, P = 0.94) or periprosthetic fracture (OR 0.59, P = 0.13) between the 2 groups. The total number of complications showed an odds benefit in favor of DM implants (OR 0.43, P < 0.001). In the subgroup analysis, there was no significant difference in the odds of rerevision due to dislocation (OR 0.69, P = 0.11) between DM and larger femoral head FB implants. Based on current literature, it appears DM implants are an effective modality for reducing dislocation following rTHA with lower complication rates compared to FB implants. However, further prospective randomized controlled trials with longer term follow-up are required.