Abstract
OBJECTIVES: It is unclear whether improvements in knee pain or physical function lead to improvements in activities of daily living (ADL) and quality of life (QOL) in patients with moderate to severe knee osteoarthritis (KOA). This study aimed to investigate whether improvements in knee pain and physical function, achieved through exercise therapy, lead to improvements in ADL and QOL in patients with moderate to severe KOA. METHODS: This case-control study included 18 patients with KOA. We evaluated knee range of motion, knee extension muscle strength (KEM), gait speed, knee pain, Knee Injury and Osteoarthritis Outcome Score (KOOS)-ADL, and KOOS-QOL at the first visit and after 3 months of exercise therapy. Patients were classified into the ADL and QOL improvement or no-improvement groups. Statistical analysis used split factorial analysis of variance with time and group as the main effects. When interactions were observed, post-hoc analysis was performed with two-sample t-tests. RESULTS: For ADL improvement, the improvements in KEM of the affected side and gait speed were statistically significant. At 3 months, the gait speed of the improvement group was significantly higher than that of the no-improvement group. For QOL improvement, there was no significant interaction for any of the factors evaluated. CONCLUSIONS: No factor showed significant contribution to improved QOL in patients with moderate to severe KOA. However, increased gait speed may improve ADL and contribute to the development of efficient rehabilitation programs for patients with moderate to severe KOA.