Physical therapy is effective for patients with osteoarthritis of the knee: a randomized controlled clinical trial

Abstract

Objective: To assess the effectiveness of physical therapy, given either as an individually attended treatment or in a small group format, in terms of pain, physical function, and health related quality of life for patients with osteoarthritis (OA) of the knee.

Methods: After 2 baseline assessments, 126 patients were randomized into one of 3 allocation arms: individual treatments (n = 43), small group format program (n = 40), and waiting list control (n = 43). After reassessment at 8 weeks, patients allocated to waiting list control were randomized into one of the 2 active treatment arms. Assessments included both self-report measures (WOMAC, SF-36) and objective measures of physical performance (gait analysis and muscle strength).

Results: Both physical therapy treatment allocations resulted in significant improvements in pain, physical function, and health related quality of life above the control group (standardized response mean 0.36 to 0.65). Improvements in the self-report measures were substantiated by significant correlated improvements in knee extensor strength and fast walking speed (rho 0.36-0.42). There were no significant differences in effectiveness between the 2 physical therapy allocations for any of the measured outcomes. Improvements gained were maintained for at least 2 months. Responsiveness to treatment was modified by loss of medial joint space width, the interaction being significant for physical function, gait, and knee extensor strength.

Conclusion: Physical therapy, either as an individually delivered treatment or in a small group format, is an effective intervention for patients with knee OA. Responsiveness to this 8 week intervention was modified by loss of medial joint space width.