A randomized controlled trial of aquatic and land-based exercise in patients with knee osteoarthritis

Objective: To compare the efficacy of aquatic exercise and a land-based exercise programme vs control in patients with knee osteoarthritis. Methods: Primary outcome was change in pain, and in addition Knee Injury and Osteoarthritis Outcome Score questionnaire (KOOS). Standing balance and strength was also measured after and at 3-month follow-up. Seventy-nine patients (62 women), with a mean age of 68 years (age range 40-89 years) were randomized to aquatic exercise (n = 27), land-based exercise (n = 25) or control (n = 27). Results: No effect was observed immediately after exercise cessation (8 weeks). At 3-month follow-up a reduction in pain was observed only in the land-based exercise group compared with control (-8.1 mm, (95% confidence interval -15.4 to -0.4; p = 0. 039), but no differences between groups were observed for KOOS; and no improvement following aquatic exercise. Eleven patients reported adverse events (i.e. discomfort) in land-based exercise, while only 3 reported adverse events in the aquatic exercise. Conclusion: Only land-based exercise showed some improvement in pain and muscle strength compared with the control group, while no clinical benefits were detectable after aquatic exercise compared with the control group. However, aquatic exercise has significantly less adverse effects compared with a land-based programme.