Effects of transcranial direct current stimulation on pain intensity in patients with chronic low back pain: a systematic review of literature

Introduction: Low back pain (LBP) is common musculoskeletal disorder in today’s societies, which lead to inducing chronic pain and consequently pathological changes in brain function in most of the patients. Therefore, using effective intervention for controlling chronic pain in patients with LBP is very important. According to the evidence, some studies indicated that pain intensity is decreased by application of trans-cranial direct current stimulation (tDCS) in the patients with CLBP. On the other hand, some studies showed that there were no significant effects on pain intensity in these patients. The aim of this study was to systematically review the studies which investigated the effects of tDCS intervention on pain intensity in patients with CLBP. Materials and Methods: The search was performed in databases of Google Scholar, PubMed, Embase, WOS, Proquest, MedLine, Scopus, Ovid, Chocrane and Science Direct with from 2000-2019. The quality of articles was assessed by Pedro scale. Results: Finally, from 177 articles, 7 articles were included in this systematic review study. The results indicated that using concurrent central and peripheral intervention or the condition of using tDCS alone was a key factor in the reporting of different findings among the included studies. The review of articles indicated that using tDCS alone has not significantly affected pain intensity, while tDCS along with peripheral electrical stimulation (PES) or training have a significant and lasting effects on pain intensity in patients with CLBP. Conclusion: TDCS along with peripheral interventions have positive and lasting effects on pain intensity in patients with CLBP. Therefore, it is suggested that tDCS will be used along with peripheral interventions to control pain intensity in patients with CLBP.