The effects of cryotherapy on pain and function in individuals with knee osteoarthritis: a systematic review of randomized controlled trials

Objective: To investigate the effectiveness of cryotherapy on pain and physical function in knee osteoarthritis. Data sources: An electronic search was performed up to February 2019 on PubMed/MEDLINE, EMBASE, CINAHL, Lilacs, Cochrane, Web of Science, Ibecs, and Scielo databases with keywords knee osteoarthritis and cryotherapy. Methods: Two authors independently performed the study selection. All languages and publication dates were considered. The PEDro scale was used to assess the methodological quality of the studies, and the body of evidence was analyzed and synthesized using the Grading of Recommendations, Assessment, Development, and Evaluation approach. The clinical relevance of the included studies was evaluated using the criteria proposed in the Cochrane Handbook for Systematic Reviews of Interventions. Results: Of the five studies, 202 subjects were included. All studies included participants with established knee osteoarthritis. The mean PEDro score was 4.20/10, and meta-analysis was not possible due to heterogeneity among the studies. The mean clinical relevance was 3/5. Only two studies were considered for analysis based on the GRADE approach, and low level of evidence was synthesized regarding the effectiveness of cryotherapy for pain management, knee stiffness, knee range of motion, and physical function. Application techniques, frequency, and duration did not affect outcomes. Conclusions: There were insufficient primary studies to draw any conclusions about the effectiveness of cryotherapy on pain and physical function on individuals with knee osteoarthritis.