Efficacy of joint lavage in knee osteoarthritis: meta-analysis of randomized controlled studies

Objective. Regarding the efficacy of joint lavage in the treatment of knee OA, we evaluated reports of randomized controlled trials (RCTs) to assess the efficacy of joint lavage alone or joint lavage combined with IA steroid injection to alleviate pain and improve function in knee OA. Methods. We searched MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials for all reports published since 1966 of RCTs, evaluating either the efficacy of joint lavage alone or of joint lavage combined with steroid injection for knee OA on pain intensity and physical function. The time point for evaluation was a priori fixed at 3 months. Effect size (ES) was calculated to compare results across studies. Results. From the 49 articles identified, reports of six RCTs were analysed for a total of 855 OA patients (511 in the treatment group and 344 in the control group). The pooled ES of the joint lavage vs placebo was not significant for pain intensity [ES = 0.17 (-0.37, 0.71)] or physical function [ES = -0.15 (-0.34, 0.04)], nor was the pooled ES of joint lavage combined with steroid injection vs joint lavage alone significant for pain intensity [ES = -0.82 (-2.47, 0.82)] or physical function [ES = 0.09 (-0.28, 0.45)]. Conclusions. This meta-analysis of RCTs investigating joint lavage for knee OA suggests that at 3 months, (i) joint lavage alone does not provide significant improvement in pain or function and (ii) the combination of joint lavage and IA steroid injection is no more efficacious than lavage alone.