The Effect of Surgical Approach on Outcomes Following Total Hip Arthroplasty Performed for Displaced Intracapsular Hip Fractures: An Analysis from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

BACKGROUND: Studies have suggested that the anterolateral approach is preferable to the posterior approach when performing total hip arthroplasty (THA) for a displaced intracapsular hip fracture, because of a perceived reduced risk of reoperations and dislocations. However, this suggestion comes from small studies with short follow-up. We determined whether surgical approach in THAs performed for hip fracture affects revision-free hip survival, patient survival, and intraoperative complications. METHODS: We retrospectively analyzed all stemmed primary THAs for hip fracture that were recorded in the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man that were performed between 2003 and 2015. The 2 surgical approach groups, posterior and anterolateral, were matched for patient and surgical confounding factors using propensity scores, with outcomes compared using regression modeling (with regression model ratios of <1 representing a reduced risk of the specified outcome in the posterior group). Outcomes were 5-year hip survival free from revision (all-cause revision, revision for dislocation and/or subluxation, and revision for periprosthetic fracture), patient survival (30 days, 1 year, and 5 years postoperatively), and intraoperative complications. RESULTS: After matching, 14,536 THAs (7,268 per group) were studied. Five-year cumulative revision-free survival rates were similar (posterior group, 97.3%, and anterolateral group, 97.4%; subhazard ratio [SHR], 1.15 [95% confidence interval (CI), 0.93 to 1.42]). Five-year survival rates free from revision for dislocation (SHR, 1.28 [95% CI, 0.89 to 1.84]) and for periprosthetic fracture (SHR, 1.03 [95% CI, 0.68 to 1.56]) were also comparable between the 2 approach groups. Thirty-day patient survival was significantly higher following a posterior approach (99.5% compared with 98.8%; hazard ratio [HR], 0.44 [95% CI, 0.30 to 0.64]), which persisted at 1 year (HR, 0.73 [95% CI, 0.64 to 0.84]) and 5 years (HR, 0.87 [95% CI, 0.81 to 0.94]) postoperatively. The posterior approach was associated with a lower risk of intraoperative complications (odds ratio [OR], 0.59 [95% CI, 0.45 to 0.78]). CONCLUSIONS: In THA for hip fracture, the posterior approach was associated with a similar risk of revision and a lower risk of both patient mortality and intraoperative complications compared with the anterolateral approach. We propose that the posterior approach is as safe as the anterolateral approach when performing THA for hip fracture and that either approach may be used according to surgeon preference. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.