Dual mobility cup in total hip replacements: a single center experience

Objective: Prosthetic joint dislocation remains a significant cause of revision following total hip replacement (THR). To prevent this complication, emphasis has been on choosing the optimum surgical approach, accurate implant alignment, bigger femoral head size, and implementing postoperative hip precautions. In the last decade, a newer acetabular design concept; the “Dual Mobility cup” (DM cup) was introduced to reduce the prosthetic dislocation. Although the concept of the use of such a device is well accepted, there remains apprehension regarding its precise indications, the outcome in terms of wear and ability to decrease the incidence of prosthetic dislocation. We reviewed the early results of a particular DM cup design. Materials and Methods: This study shares a single center experience of using a monoblock DM cup (Captiv DM, Evolutis, Briennon, France) in THR. It is a prospective cohort study that looked at indications, handling issues, complications including prosthetic dislocations at 24 months follow-up. Results: We followed up results of uncemented and cemented DM cup used in 129 patients who underwent primary THR or revision THR (RTHR). There was one (1.6%) prosthetic dislocation amongst primary THR and 2 (3%) in the RTHR group. There were handling issues with monoblock uncemented DM cups of occasional improper seating and acetabular rim fracture. Three cases in which revision was performed, were due to component to component impingement and resulted due to inappropriate acetabular version. Conclusion: The use of DM cups while performing THR or RTHR significantly decreased the incidence of instability. While placing DM cups an attempt should be made to maintain the native version of the acetabular cup to decrease the risk of component impingement and instability. Level of Evidence: Level III, therapeutic study.