Dual mobility cups reduce dislocation in isolated cup revision

Dual-mobility cup (DMC) is gaining increasing attention in total hip arthroplasty (THA) revision due to its numerous advantages. However, the prognosis after isolated cup revision with DMC remains unclear. This study aimed to compare complications, focusing on dislocation, and analyze clinical outcomes in patients who underwent isolated cup revision after THA.

This retrospective cohort study included 119 patients who underwent isolated cup revision after THA and were followed up for ≥ 2 years from January 2009 to February 2020. Patient demographics, including age, sex, surgical approach, reasons for previous joint replacement surgery, and postoperative complications, were investigated. The patients were divided into DMC and conventional cup (CC) groups, and operative data and postoperative complications were compared between the two groups. Clinical outcomes were compared using the Harris hip score.

Forty-nine patients received DMC, and 70 received CC; the two groups had no difference in preoperative evaluation. Although the implants used significantly differed, there was no difference in the cup position. Six patients in the CC group had dislocations, but none had them in the DMC group (p = 0.042). Aseptic loosening was the most frequent postoperative complication but showed no significant difference between the two groups.

DMC in revision THA can prevent dislocation compared to CC. In particular, DMC is considered a good treatment option in isolated cup revision wherein the surgeon can control the limited options.