Functional Burden and Quality of Life in Hip and Knee Osteoarthritis: A Cross-Sectional Study

Background and Objectives: Osteoarthritis, the most common degenerative joint disease, causes pain, decreased mobility, and functional disability, having a significant impact on patients' quality of life. This study aimed to evaluate the impact of hip osteoarthritis (HOA) and knee osteoarthritis (KOA) on physical functioning and quality of life, and to explore how these outcomes vary according to sex, disease stage, and common comorbidities. Materials and Methods: A cross-sectional study was conducted between 1 October and 30 December 2024, at the Medical Rehabilitation Department of Avram Iancu Clinical Hospital in Oradea, Romania. A total of 133 adult patients diagnosed with HOA or KOA, based on clinical and radiographic criteria, were included. Functional status was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), while quality of life was evaluated using the World Health Organization quality of life questionnaire-BREF version (WHOQOL-BREF). The main outcomes were the total scores of these instruments, analyzed in relation to demographic and clinical variables. Results: Based on the clinical staging criteria applied in the study, 23 patients (17.3%) were classified as being in the early stage, 98 (73.7%) in the progressive stage, and 12 (9.0%) in the advanced or end stage of the disease. The mean WOMAC total score was 52.0 ± 7.9 (scale: 0-96), indicating moderate to severe functional impairment. The mean WHOQOL-BREF score was 67.9 ± 13.1 (scale: 0-100), reflecting a moderately reduced quality of life. A moderate, statistically significant inverse correlation was observed between WOMAC and WHOQOL-BREF scores (Spearman's rho = -0.565, p < 0.001). Patients with knee osteoarthritis reported significantly lower quality of life compared to those without this condition (66.48 ± 12.73 vs. 71.76 ± 13.31, p = 0.006). No statistically significant differences were found in functional, or quality-of-life scores based on sex. Conclusions: Knee osteoarthritis, particularly when combined with hip involvement, is associated with a substantial decline in quality of life and functional capacity. The severity and location of joint involvement appear to be the primary determinants of disability in this patient population, while systemic comorbidities have a less pronounced influence in the rehabilitation setting.