Does Activity Level After Primary Total Hip Arthroplasty Affect Aseptic Survival?

Background: The purpose of this study is to evaluate survivorship and outcomes of high-activity patients compared to low-activity patients after total hip arthroplasty. Methods: A retrospective review identified 2002 patients (2532 hip) that underwent a primary total hip arthroplasty with vitamin E–infused highly crosslinked polyethylene liner. Patients were divided into 2 groups based on their University of California Los Angeles (UCLA) activity level: low activity (LA) (UCLA ≤5) and high activity (HA) (UCLA ≥6). Outcomes included Harris Hip Score, UCLA activity score, and reoperations. A multivariate nominal regression analysis was performed to evaluate the significance of postoperative activity level on survivorship. Results: The mean follow-up duration was 4.5 years (range, 0.3 to 9.9 years). HA group had significantly higher improvements in Harris Hip Score (HHS) (P < .001) and UCLA activity score (P < .001). Aseptic revisions were performed in 2.1% of the LA group and in 0.4% hips of the HA group (P < .001). After controlling for age, gender, preoperative pain, HHS, and body mass index, a higher postoperative activity level remained a significant factor for improved aseptic survivorship with an odds ratio of 4.9 (95% confidence interval, 1.1 to 21.2, P = .03). The all-cause 5-year survivorship was 99% for the HA group and 96% to for the LA group (P < .001). The aseptic 5-year survivorship was 99.6% for the HA group and 98% for the LA group (P < .001). Conclusions: This study found that a higher activity level after primary THA was not deleterious to survivorship at short to midterm follow-up with modern implants.