Low and High Functioning Patients Have Equivalent Outcomes Following Modern-Day Primary Total Hip Arthroplasty

Michael Tanzer 1 Mohammad Mesfer Alzahrani 1 Karen Smith 1 Dylan Tanzer 2
1Department of Surgery, McGill University, Division of Orthopaedic Surgery, Montreal, Canada
2Tel Aviv University, Sackler Medical School, Tel Aviv, Israel

Introduction: Previous studies have suggested that patients who undergo total hip arthroplasty (THA) with poorer physical function have a lower functional outcome than patients with less preoperative disability. However, with recent improvements in perioperative management protocols and surgical techniques, health-related quality of life (HRQoL) outcomes have markedly improved for all patients following THA. Our objective was to determine if the preoperative level of function, determined by HRQoL scores, was predictive of the outcome at 2 years, in patients undergoing THA using modern perioperative protocols and surgical techniques.

Methods: A prospective cohort study design evaluated the preoperative and 2 year postoperative SF-12 and WOMAC HRQoL scores of 200 consecutive patients who underwent THA with modern, and identical, perioperative management protocols, surgical techniques and cementless implants. The cohort was divided into two groups according to the median preoperative WOMAC physical function scores. A one-way ANOVA was used for statistical analysis.

Results: Both the High and Low Function groups, had significant improvements in their Harris Hip Scores and HRQoL scores (p<0.001). However, this postoperative improvement was significantly greater in the Low Function group. As a result, there was no difference in the HRQoL outcomes of the two groups at final follow up. Compared to the population-based normative values for individuals of the same age and gender, the vast majority of patients in both groups attained HRQoL values that were considered normal,.

Discussion and Conclusion: This study clearly contradicts the previously held belief that patients with worse function prior to THA do not do as well as patients with less preoperative disability. Both patients with greater or lesser preoperative functional limitations have significant improvement and equal outcomes following modern-day THA.