The efficacy and safety of hydrotherapy in patients with knee osteoarthritis: a meta-analysis of randomized controlled trials

Background: Currently, there is poor evidence of the effect of hydrotherapy on patients with knee osteoarthritis. We performed a meta-analysis from randomized controlled trials to determine the efficacy and safety of a hydrotherapy program on measures of pain and knee function in individuals living with knee osteoarthritis. Methods: A literature review included PubMed, EMBASE, Cochrane Library, Science Citation Index, ScienceDirect and Ovid. Studies evaluating the efficacy of hydrotherapy for knee osteoarthritis up to August 2023 were included. The research was reported based on the preferred reporting items for systematic reviews and meta-analysis guidelines to ensure the reliability and verity of results. Statistical analysis was performed using Stata/SE version 15.0. Results: A total of six randomized controlled trials were included for data extraction and meta-analysis. The present study revealed that there were significant differences between the two groups regarding the pain intensity at 1 week (WMD= -0.429; 95% CI: -0.679 to -0.179; P =0.001), 4 week (WMD= -0.308; 95% CI: -0.587 to -0.030; P =0.030) and 8 week(WMD= -0.724; 95% CI: -1.099 to -0.348, P <0.001). Furthermore, hydrotherapy was associated with improved outcome of the Western Ontario and McMaster Universities Arthritis index at 1 week (WMD= -3.314; 95% CI: -6.484 to -0.145, P =0.040), 4 week (WMD= -3.630; 95% CI:-6.893 to -0.366, P =0.029) and 8 week (WMD= -3.775; 95% CI: -7.315 to -0.235; P =0.037). No serious adverse events were observed in all patients who received hydrotherapy. Conclusion: Hydrotherapy is efficacious and safe for reducing pain and improving functional status in individuals with knee osteoarthritis, without increasing the risk of adverse effects.