Use of a modular hip dual-mobility articulation in patients with high risk of dislocation: a relatively small-sized acetabulum in Asian patients may limit its use

BACKGROUND: Dual-mobility hip component is widely used in Europe and North America, because it effectively reduces hip dislocation in primary and revision total hip arthroplasties. However, reports were limited on the use of dual-mobility articulation in Asian populations. PURPOSE: The aim of this retrospective study was to review the use of modular dual-mobility hip articulation in Asian patients with the high risk factor for hip dislocation. We also discussed the potential concern on the use of dual-mobility articulation in Asian patients. METHODS: From Jan 2018 to June 2019, 17 patients were included in this study. The mean age of the patients was (73.8 ± 9.5) years (range: 57–88 years). The mean size of acetabular cup and modular DM liner were (49.5 ± 3.4) mm (range, 46–58 mm) and (40.7 ± 3.4) mm (range, 38–48 mm), respectively. The mean follow-up period was (15.8 ± 3.9) months (range, 11–24 months). The primary outcome was the rate of hip dislocation. The secondary outcomes included the Harris Hip Score. Differences were considered statistically significant at p < 0.05. RESULTS: Hip dislocation, loosening, peri-prosthetic fractures, or intra-prosthetic dislocation was not found in the series. The mean preoperative and postoperative Harris Hip Scores were 42.2 ± 17.2 (range, 15–80) and 74.7 ± 13.5 (range, 52–97), respectively, giving a mean improvement of 32.5 ± 17.2 (range, 4–72). The improvement was statistically significant (p < 0.05). CONCLUSIONS: In Asian patients with high risk of hip dislocation, the use of modular dual-mobility hip component produces promising outcomes without hip dislocation, but the relatively small-sized acetabulum may limit it widespread application in other populations worldwide. TRIAL REGISTRATION: HKUCTR-2913.