Effectiveness of exercise therapy in patients with osteoarthritis of the hip or knee - A systematic review of randomized clinical trials

Objective. To review the effectiveness of exercise therapy in patients with osteoarthritis (OA) of the hip or knee. Methods, A computerized literature search of Medline, Embase, and Cinahl wa s carried out, Randomized clinical trials on exercise therapy for OA of the hip or knee were selected if treatment had been randomly allocated and if pain, self-reported disability, observed disability, or patient's global as sessment of effect had been used as outcome measures. The validity of trial s was systematically assessed by independent reviewers. Effect sizes and po wer estimates were calculated. A best evidence synthesis was conducted, wei ghting the studies with respect to their validity and power. Results. Six of the 11 assessed trials satisfied at least 50% of the validi ty criteria. Two trials had sufficient power to detect medium-sized effects . Effect sizes indicated small-to-moderate beneficial effects of exercise t herapy on pain, small beneficial effects on both disability outcome measure s, and moderate-to-great beneficial effects according to patient's global a ssessment of effect. Conclusion. There is evidence of beneficial effects of exercise therapy in patients with OA of the hip or knee. However, the small number of good stud ies restricts drawing firm conclusions.