Clinical bottom line
Dual mobility (DM) implants in total hip arthroplasty (THA) offer a promising option to reduce postoperative dislocation risk, particularly in patients at high risk for instability. Current systematic reviews and comparative studies suggest that DM cups provide superior dislocation prevention compared to conventional implants, including jumbo femoral heads, in both primary and revision THA settings. However, rare but specific complications such as intraprosthetic dislocation warrant cautious patient selection and surgical technique. Overall, DM implants represent a valuable tool in the orthopedic surgeon’s armamentarium for improving stability after THA, though further long-term data and randomized trials are needed to refine indications and optimize outcomes.
What the evidence shows
Multiple systematic reviews and meta-analyses have evaluated the efficacy of DM implants in preventing dislocation after THA. Romagnoli et al. (2019) conducted a meta-analysis of comparative studies and found that DM cups significantly reduced dislocation rates compared to conventional single mobility implants, with a pooled odds ratio favoring DM use. This effect was consistent across primary and revision THA cohorts. Similarly, Giacomo et al. (2021) reviewed revision THA cases and confirmed that DM implants lowered dislocation risk compared to standard implants, supporting their use in complex revision scenarios.
Beckert et al. (2022) compared DM implants to jumbo femoral heads in primary THA patients at risk for instability and reported that DM cups were associated with fewer dislocations and comparable complication rates. This suggests DM implants may offer an advantage over other large-head strategies traditionally employed to enhance stability.
In high-risk populations, including those with neuromuscular disorders or prior instability, Young et al. (2020) highlighted the utility of DM implants in reducing dislocation incidence, reinforcing their role as a targeted intervention. Faldini et al. (2018) emphasized the importance of addressing patient-specific risk factors and noted that DM implants are a key option among treatment strategies to prevent dislocation after revision THA.
However, the use of DM implants is not without unique complications. Hermena et al. (2021) described intraprosthetic dislocation—a failure mode specific to DM designs where the polyethylene liner dissociates from the femoral head—as an uncommon but serious event requiring awareness and prompt management.
Caveats and uncertainty
Despite encouraging data, most evidence derives from observational studies, retrospective cohorts, and meta-analyses of heterogeneous populations. Randomized controlled trials comparing DM implants to other stability-enhancing options remain limited. Variability in implant design, surgical technique, and patient selection criteria complicates direct comparisons and generalizability.
Long-term outcomes beyond mid-term follow-up are less well characterized, particularly regarding wear rates, implant survivorship, and the incidence of intraprosthetic dislocation over time. The risk-benefit balance in low-risk patients is unclear, and indiscriminate use of DM implants may expose patients to unnecessary risks or costs.
Furthermore, surgical expertise and familiarity with DM implant-specific considerations are critical to minimizing complications. The learning curve and implant-specific technical nuances may influence outcomes but are not well quantified in the literature.
How this may change practice
Orthopedic surgeons should consider dual mobility implants as a valuable option for patients at elevated risk of dislocation following primary or revision THA, including those with neuromuscular conditions, prior instability, or complex revision anatomy. Incorporating DM implants into surgical planning may reduce postoperative instability rates and associated morbidity.
Surgeons should weigh the benefits against potential complications such as intraprosthetic dislocation and ensure appropriate patient counseling. Familiarity with implant-specific surgical techniques and vigilant postoperative monitoring are essential to optimize outcomes.
Further high-quality prospective studies and randomized trials are needed to define precise indications, long-term durability, and cost-effectiveness. Meanwhile, DM implants represent an important advancement in THA stability management that may shift practice patterns toward more widespread use in selected high-risk cohorts.