Satisfactory Survivorship and Clinical Outcomes After Acetabular Revision With the Three-Dimensional–Printed Porous Metal Monoblock Dual-Mobility Cup: A Retrospective Case Series With Mean 3 Years Follow-Up
Abstract
Background Acetabular revision total hip arthroplasty is associated with high rates of instability and aseptic loosening. Dual-mobility cups (DMCs) reduce dislocation risk and three-dimensional (3D)-printed porous metal surfaces enhance biologic fixation. The combination of these 2 technologies in a monoblock cementless construct has not been specifically evaluated in the revision setting. The purpose of this study was to assess short- to mid-term survivorship, clinical and radiographic outcomes, and complications of a 3D-printed porous monoblock DMC used in acetabular revision. Methods We retrospectively reviewed 89 consecutive patients who underwent acetabular revision with the a 3D-rinted porous monoblock DMC between November 2017 and June 2024 at a single academic institution. The primary endpoint was all-cause re-revision; secondary outcomes were Harris Hip Score, complications, and radiographic assessment using the DeLee and Charnley zones. Implant survival was estimated by Kaplan–Meier analysis. Results Mean follow-up was 44.3 ± 24.9 months. Five patients (5.6%) underwent re-revision. The 2-year and 5-year survival rates were 95.4% (95% confidence interval, 88.2-98.2) and 93.2% (95% confidence interval, 83.7-97.2), respectively. The mean Harris Hip Score improved from 48.8 ± 18.2 preoperatively to 94.4 ± 11.5 at the latest follow-up (P < .001), with 95.0% of patients achieving the minimal clinically important difference. The conventional dislocation rate was 1.1%. No cup demonstrated radiographic loosening; non-progressive radiolucent lines were observed in 35 patients (39.3%). Conclusions The 3D-printed porous monoblock DMC provided reliable fixation, excellent functional improvement, and a low dislocation rate in acetabular revision with predominantly contained defects at short- to mid-term follow-up.