Outcomes of total hip arthroplasty using dual mobility cups following failed internal fixation of proximal femoral fractures at a mean follow-up of 6 years.

Introduction: Performing total hip arthroplasty (THA) after failed internal fixation of proximal femoral fractures (PFF) is known to be associated with high rates of complications. Dual mobility cups (DMC) are known to lower dislocation events in high-risk patients. Very few reports investigated the outcomes of THA using DMC following failure of internal fixation for PFF.

Methods: This is a retrospective monocentric continuous study of 31 patients who underwent THA with DMC after failed internal fixation of PFF. The clinical assessment was based on the modified Harris hip score (mHHS) at the last follow-up. The complication rates and radiological analyses were recorded.

Results: The mean follow-up period was 5.96 ± 4.2 years. At the last follow-up, the mean mHHS was 92.9 ± 9.1 with 71% of the patients describing their operated hip as a forgotten hip. No dislocation or aseptic loosening events were noted. One patient developed a septic loosening of the implant. No significant radiological changes were recorded. Sixteen stems (51.6%) were placed in a neutral position, 13 (42%) in valgus (2.74 ± 1.72°), and 2 (6.4%) in varus (6.94 ± 2.02°).

Conclusion: This study emphasizes the advantage of using DMC following failed internal fixation of PFF in reducing dislocation and complication events in this high-risk population.