Cryotherapy in Knee Osteoarthritis: A Systematic Review With Meta-Analysis

Abstract

Objective: To update knowledge on the effects of cryotherapy in reducing pain, increasing strength, and improving function in patients with knee osteoarthritis. Methods: The databases used included PubMed, Embase, Cochrane, Physiotherapy Evidence Database (PEDro), Scopus, Web of Science, and LILACS. In addition, gray literature was searched in Google Scholar, LIVIVO, Open Gray, and the CAPES Library of Theses and Dissertations. The risk of bias was assessed using the Cochrane tool, RoB 2, by two independent reviewers, with conflicts being resolved by consensus. The primary outcome was pain, while secondary outcomes included functionality and muscle strength. Results: Five randomized controlled trials were selected from 2094 initial registrations. The meta-analysis included all five studies in the pain intensity outcome, resulting in a standardized mean difference (SMD) of −0.57 (95% CI: [−0.97, −0.18]; p = 0.004; I2 = 42%). In addition, four studies were included in the functionality outcome, with an SMD of −0.28 (95% CI: [−0.58, 0.02]; p = 0.07; I2 = 0%). Only one study assessed muscle strength. Conclusion: These findings indicate that cryotherapy can be useful as part of a comprehensive treatment for knee osteoarthritis, especially when combined with kinesiotherapy, but its effectiveness as a stand-alone treatment still requires further studies with a lower risk of bias.