20-YEAR EXPERIENCE WITH DUAL MOBILITY IN PRIMARY TOTAL HIP ARTHROPLASTY: WHOLE CONSTRUCT OUTCOME

Dual mobility (DM) is an established option in total hip arthroplasty (THA), though long-term data, particularly on whole construct outcomes remain very limited. We present a retrospective review of a consecutive series of high-risk patients selected using evidence-based criteria to undergo primary DM THA. Outcomes included re-operation for any cause, including peri-prosthetic fracture (PPF). Patients undergoing DM THA between March 2006 and October 2024 were identified using national digital health records capturing all healthcare episodes. The cohort comprised 318 cases with a mean age of 74.4 years (range 21.3–94.1). At a median follow-up of 7.4 years (range 1.0–19.6), Kaplan–Meier analysis demonstrated survivorship free from all-cause revision or major re-operation of 97.9% (95% CI 94.8–99.1). Non-osteoarthritis indications accounted for 39.6% of cases. There were 2 dislocations (0.63%) and 5 revisions (2 for prosthetic joint infection, 2 for PPF, and 1 for instability). Four additional PPFs were treated surgically (1 type B, 3 type C), and one was managed non-operatively. Post-operative PPF was the most common complication (2.2%), occurring at a mean of 3.5 years. Mean Oxford Hip Score improvement was 24.6. These findings support the long-term effectiveness of DM implants in patients at high risk of instability. PPF remains the leading cause of re-operation, likely reflecting a population also at high risk of falls. Careful consideration of patient and implant factors is essential when selecting bearing surfaces.