Constrained Acetabular Liners Implanted Simultaneously at the Time of Acetabular Revision Using Contemporary Components.

Abstract

Concern for early acetabular component loosening may deter surgeons from using a constrained acetabular liner (CAL) at the time of acetabular component revision. We have previously demonstrated this can be safely and effectively done with a highly porous tantalum shell, numerous screws, and a cemented constrained liner. It is not known, however, whether similar outcomes are achievable with contemporary modular acetabular components with a liner-locking mechanism. A retrospective review of our total joint registry from 2000 to 2021 identified 38 cases of revision total hip arthroplasties (THAs) in which a CAL was inserted into a contemporary revision acetabular component placed during the same surgery. All cases received supplemental screw fixation (mean of four screws). The mean age at revision THA was 66 years, 74% of patients were women, and the mean body mass index was 31. The most common indications for index revision THA were recurrent dislocation (57%), aseptic loosening (20%), and two-stage reimplantation (26%). The mean follow-up was 4 years. The 5-year survivorship free from acetabular rerevision for aseptic loosening was 97%, any acetabular rerevision was 94%, and any rerevision was 77%. There was only one acetabular component revised for aseptic loosening at 2 years. There were eight re-revisions performed for dislocation (4), periprosthetic joint infection (2), aseptic loosening (1), and periprosthetic fracture (1). Radiographic review did not identify any evidence of acetabular component loosening in unrevised cases. Selective use of a CAL at the time of acetabular revision with a contemporary acetabular component and multiple screws had a low rate of aseptic loosening. These results suggest that a CAL can be utilized at the time of acetabular revision when a stable acetabular component is inserted with robust screw fixation. Level IV.