Patient acceptable symptom state (PASS) thresholds for the Hip disability and Osteoarthritis Outcome Score (HOOS) after total hip arthroplasty.

Abstract

Total hip arthroplasty (THA) is an effective treatment for hip osteoarthritis (OA). The patient acceptable symptom state (PASS) provides meaningful thresholds for patient-reported outcomes. However, short-term PASS after THA remains underexplored, despite its importance in identifying early recovery status, guiding timely postoperative interventions, and supporting patient expectations during the critical early rehabilitation phase. This study aimed to determine short-term PASS thresholds for each Hip disability and Osteoarthritis Outcome Score (HOOS) subscale. This multicenter prospective cohort study evaluated 150 patients with hip OA who underwent primary unilateral THA. PASS thresholds for the HOOS subscales-symptoms, pain, activities of daily living (ADL), sport and recreation (SR), and quality of life (QOL)-were calculated at 3 and 6 months after THA using both the 25th percentile method and receiver operating characteristic (ROC) analysis, anchored to the Global Rating of Change scale. At 3 months post-THA, the PASS thresholds (percentile/ROC) were: symptoms 60.0/47.5, pain 70.0/56.3, ADL 60.3/72.8, SR 37.5/28.1, and QOL 37.5/28.1. At 6 months post-THA, the PASS thresholds (percentile/ROC) were: symptoms 70.0/52.5, pain 82.5/72.5, ADL 77.9/72.8, SR 37.5/37.0, and QOL 62.5/46.9. This study provides preliminary short-term PASS thresholds for the HOOS subscales after THA in patients with hip OA. These early benchmarks may assist clinicians in identifying patients who appear to be experiencing suboptimal recovery as early as 3 months post-THA, potentially enabling timely postoperative support. Short-term PASS thresholds may offer helpful indicators of expected early recovery and support shared decision-making during follow-up. While these findings suggest potential clinical practice value, further studies with larger and more diverse populations are needed to enhance generalizability and confirm applicability.