Isolated RingLoc Polyethylene Liner Revision for Treatment of Liner Wear

Polyethylene wear and osteolysis has long been an issue with the survivorship of total hip arthroplasty. The purpose of this study was to assess the survivorship after isolated liner exchange with the use of the RingLoc acetabular cup. A query of our practice registry revealed 106 patients (112 hips) with a single cementless titanium plasma sprayed acetabular component (RingLoc, Zimmer Biomet, Warsaw, IN), who underwent acetabular liner exchange for treatment of polyethylene wear between January 2001 and March 2015. Eighty patients (85 hips) met inclusion criteria. Clinical outcomes were assessed with the Harris hip score and radiographic evaluation was performed. The mean follow-up after liner exchange was 6 years (range, 2-15.7 years). Harris hip scores improved from 70.9 (range, 28-100) preoperatively to 79 (range, 29-100) at most recent evaluation (p < 0.001). Subsequent surgery was required in 11 patients (11 hips, 13%). Components were revised in 7 hips (8.2%). One acetabular revision was performed for aseptic loosening and four for instability (4.7%). One metal-polyethylene sandwich liner was revised for metal hypersensitivity. One patient underwent two-staged exchange for infection. In our early to mid-term experience with the RingLoc acetabular cup, isolated liner exchange for treatment of polyethylene wear yielded 98.8% acetabular survival for aseptic loosening at up to 15 years. (Journal of Surgical Orthopaedic Advances 29(2):59-64, 2020).