Use of elevated liners in primary total hip arthroplasty: a systematic review of the literature

Purpose Instability remains one of the most frequent complications requiring revision surgery after primary total hip arthroplasty (THA). Elevated liners are often utilized to reduce the risk of dislocation; however, the literature is inconclusive, with no systematic reviews summarizing the data. Thus, this systematic review aimed to establish a consensus for the efficacy of elevated liners in primary THA by determining rates of overall revision and revision specifically for recurrent dislocation. Materials and methods This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eligible randomized-controlled trials and observational studies reporting on the use of elevated liners in primary total hip arthroplasty were identified through May 2020. A random effects model meta-analysis was conducted, and the I-2 statistic was used to assess for heterogeneity. Results Eight studies met inclusion criteria, and overall, 26,507 patients undergoing primary THA with use of an elevated liner were included. In aggregate, the most common cause of revision was recurrent hip dislocation (1.3%, N = 82/6,267) followed by joint infection (1.2%, N = 45/3,772) and acetabular loosening (0.3%, N = 10/3,772). Notably, elevated liners were associated with a lower risk of revision for recurrent dislocation compared to neutral liners (HR: 0.74; 95% CI: 0.55-1.00; p = 0.048). Conclusion This review found that after primary THA with the use of elevated liners, hip dislocation and prosthetic joint infection continued to be the most frequent reasons for revision surgery. However, elevated liners had a lower risk of revision for recurrent dislocation compared to neutral liners.