The use of cemented dual mobility acetabular cup in revision hip arthroplasty

Purpose
Instability is always an important problem after both primary and revision total hip arthroplasty (rTHA). Dual mobility or tripolar unconstrained acetabular components give a solution for preventing and treating instability. Results of many studies using dual mobility cups (DMC) with mid-term to long-term follow-up support their effectiveness. Complications such as intraprosthetic dislocation (IPD) and accelerated wear have been studied, although they seem to be less significant in older, low-demand patients. However, their use in younger patients should be with caution owing to the lack of current data concerning this high-demand patient population. The aim of this study is to analyze the short-term results of cemented DMCs in rTHA. Specifically, we evaluated the following: clinical outcomes and scoring, dislocation, IPD rates, and other complications.
Patients and methods
The results of a single design of DMC was prospectively evaluated in a continuous series of 20 rTHAs. Follow-up period was of at least 2 years. Mean age of the patients was 66.8 years old.
Results
At the 2-year mean follow-up, the dislocation rate was 5%, and the IPD rate was 0%. Improvement of the hip score, function, pain, and range of motion was noticed.
Conclusion
DMCs demonstrated a low dislocation rate in rTHA but did not solve problems related to perioperative technical errors. Moreover, IPD did not appear to be a concern when compared with the gain of preventing instability.