Dual mobility hip arthroplasty provides better outcomes compared to hemiarthroplasty for displaced femoral neck fractures: a retrospective comparative clinical study.

Purpose: Total hip arthroplasty with a dual mobility cup (DMC) is a proposed alternative to the widely performed bipolar hemiarthroplasty (BHA) for treating displaced intracapsular femoral neck fractures (DFNF) in the elderly. However, the comparison between the two modalities has not been extensively conducted thus far.
Methods: A retrospective cohort study was conducted with DFNF patients aged over 65 years who were treated either by BHA or DMC. After propensity matching each group comprised 84 patients (168 patients in total) and was analyzed using peri-operative and post-operative parameters.
Results: Mean follow-up durations were 22.1 and 21.7 months in the BHA and DMC groups, respectively. The BHA group demonstrated significantly less intra-operative blood loss (p = 0.001) and a shorter length of operation (p < 0.001). However, there was no difference in one-year mortality (p = 0.773). The Harris hip score (HHS) was significantly higher (p = 0.018) in the DMC group. The dislocation rate was not different between the two groups (p = 1.000).
Conclusion: In DFNF patients aged over 65 years, short-term observation showed DMC to be the preferred treatment over BHA with better clinical outcome, without disadvantages in mortality or dislocation rate. Further long-term investigations are recommended to strengthen these results.