Li Chen, Xin Duan, Fei Xing, Guoming Liu, Min Gong, Lang Li, Ran Chen, Zhou Xiang
Department of Orthopedics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, 610041 Chengdu, China
DOI: 10.2340/16501977-2613

Objective: To evaluate the efficacy of classical pulsed electromagnetic field therapy on patients with knee osteoarthritis.
Methods: The databases PubMed, EMBASE, Web of Science and Cochrane Library were searched for relevant studies. Randomized controlled trials comparing classical pulsed electromagnetic field with placebo for patients with knee osteoarthritis were included. Data for primary outcomes, including pain, stiffness and physical function, were extracted. Data from 8 randomized controlled trials involving 421 patients were pooled.
Results: Pulsed electromagnetic field therapy had an effect on improving physical function (weighted mean difference; WMD = −5. 28, 95% confidence interval; 95% CI −9. 45 to −1. 11, p = 0. 01), but showed no advantage in the reduction of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (WMD = −7. 80, 95% CI −16. 08 to 0. 47, p = 0. 06), WOMAC pain score (WMD = −1. 06, 95% CI −2. 30 to 0. 17, p = 0. 09), visual analogue scale pain score (WMD=−0. 88, 95% CI −2. 06 to 0. 31, p = 0. 15) or WOMAC stiffness score (WMD = −0. 50, 95% CI −1. 09 to 0. 09, p = 0. 1).
Conclusion: Pulsed electromagnetic field therapy is beneficial for improving physical function despite having no advantage in treating pain and stiffness. Further randomized controlled trials are needed to confirm these findings and determine the optimal parameters and treatment regimen for pulsed electromagnetic field therapy.

Knee osteoarthritis is currently one of the most common joint diseases worldwide. Pulsed electromagnetic field therapy has become popular among patients with knee osteoarthritis in recent years. However, the efficacy of this therapy on joint pain, joint stiffness and physical function is regarded as controversial in published clinical trials and systematic reviews. Several new randomized controlled studies on this subject have been published recently. The aim of this systematic review and meta-analysis is therefore to assess the efficacy of classical pulsed electromagnetic field therapy on patients with knee osteoarthritis, according to the methodology set out in the Cochrane Handbook for Systematic Reviews of Interventions. The results show that, despite showing no advantage in the management of pain and stiffness, pulsed electromagnetic field therapy is beneficial for improving clinical symptoms, such as physical function of the knee joint; thus it may be recommended as a supplementary therapy option for knee osteoarthritis. This review provides some evidence to help resolve current controversies about the efficacy of pulsed electromagnetic field therapy for knee osteoarthritis.

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