The effectiveness of exercise therapy in patients with osteoarthritis of the hip or knee: A randomized clinical trial

Objective. To determine the effectiveness of exercise therapy in patients w ith osteoarthritis (OA) of the hip or knee. Methods. A randomized single blind, clinical trial was conducted in a prima ry care setting. Patients with hip or knee OA by American College of Rheuma tology criteria were selected. Two intervention groups were compared. Both groups received treatment From the patients' general practitioner, includin g patient education and medication if necessary. The experimental group als o received exercise therapy from a physiotherapist in primary care. The tre atment period was 12 weeks. The main outcome measures were pain, medication use (nonsteroidal antiinflammatory drugs, NSAID) and observed disability. Results. A total of 201 patients were randomized. Exercise therapy was asso ciated with a reduction of pain in the past week (difference in change -17. 0; 95% CI -23.6, -10.4) and observed disability (-0.19, 95% CI -0.38, -0.01 ). Effect sizes were medium (0.58) and small (0.28), respectively. No effec t of exercise therapy was found for the use of NSAID. Additional beneficial effects (p = 0.05) were found for the use of paracetamol (effect size 0.33 ), global effect as perceived by the patient (effect size 0.68), and muscle strength of the hip (effect size 0.34). Conclusion. After 12 weeks, exercise therapy is effective in reducing pain and disability. The size of the effects is medium and small, respectively.