Effects of pulsed electromagnetic field therapy on pain, stiffness and physical function in patients with knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Abstract

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 metaanalysis 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. 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.

Pain and Functional Scores in Patients Affected by Knee OA after Treatment with Pulsed Electromagnetic and Magnetic Fields: A Meta-Analysis

“…Five previous meta-analyses have been published on the same topic in the past, reporting improvements in pain 17 or functional scores. 16,28,30,55 The present work comprises an unprecedented number of studies and patients, and considering all the studies, it was able to identify differences only in pain score. Interestingly, a clear difference emerged between placebo-controlled studies and studies considering alternative treatments for the control group.…”

Neuromodulation for Pain Management in the Inpatient Setting: A Narrative Review

“…In general, this therapy was used in osteoarthritis [ 50 ]. More specifically, it was used in knee osteoarthritis [ 51 , 52 ], with doubtful results. When studying the use of PEMF in low back pain, Andrade et al [ 53 ] found several concerns worth mentioning: (1) when compared to standard therapies (physiotherapy, analgesic therapy), there was low/no effect seen with PEMF; (2) there was simply a small effect size seen in many studies; (3) significant heterogeneity was seen between PEMF protocols making it difficult to compare results; and (4) internal validity issues were noted such as (a) intention to treat analysis, (b) randomization concealment, (c) lack of blinding, and (d) failgure to address conflicts of interest.…”

Osteoarthritis year in review 2020: rehabilitation and outcomes

“…This included one SR of guidelines 14 , one SR of SRs and meta-analyses 16 , and 16 SRs of RCTs (Table II). Interventions investigated included various individual (aquatic 19 , whole body vibration 22 , proprioceptive 21 , yoga 30 , resistance-based 20 ) or combined 14,16,18,28,31 exercisetherapies/physical activities, technologies (wearable activity trackers) 15 and behaviour change approaches 17 to improve adherence to exercise and physical activity (PA), and modalities (Extracorporeal Shockwave Therapy; ESWT 23,24,29 , Pulsed Electromagnetic Field Therapy; PEMF 25 , laser therapy 26 ; and therapeutic ultrasound 27 ).…”