Impact of primary surgical approach on revision approach for isolated head-liner exchange in total hip arthroplasty.

Introduction: Isolated femoral head and polyethylene liner exchange is commonly performed with varying surgical approaches used for the primary THA (pTHA) and the revision THA (rTHA). The purpose of this study is to investigate the prevalence and postoperative outcomes associated with concordance and discordance in isolated head-liner exchange.

Methods: A retrospective chart review from May 2016 to November 2023 was performed for all patients at 2 institutions who underwent isolated head-liner exchange. 175 patients had minimum 1-year follow-up with complete information regarding surgical approach and outcomes. 175 included were grouped based on their pTHA approach including posterior approach (PA), anterolateral (AL), and direct anterior (DA), and their subsequent rTHA approach. Demographics and postoperative outcomes were compared between groups. Chi-square tests were used to measure associations between surgical approaches and postoperative complications, with a p-value of <0.05 signifying statistical significance.

Results: Our study included 175 patients with isolated head-liner exchange, with a mean age of 68.5 ± 10.4 years. Of the 175 patients, 100 (57.1%) received primary THA via the posterior approach (PA), with 68.0% having concordant revisions. For the anterolateral (AL) and direct anterior (DA) primary approaches, 91.1% and 94.7% of revisions were concordant, respectively. Indication for revision differed by approach, particularly within the PA group, where instability favoured concordant revisions, and metallosis favoured discordant revisions. There was no significant difference in perioperative outcomes between concordant and discordant approaches, except the concordant group had more EBL, higher rates of transfusions, reoperations, and discharge to skilled nursing facilities (SNF).

Conclusions: In pTHA cohort, patients with PA approach were more likely to undergo head-liner exchange with a discordant approach via DA or AL. As no significant associations were found in any combination of discordant approaches with postoperative complications, surgeons should choose their head-liner approach without significant concern for discordance.