A review of pulsed electromagnetic field (PEMF) mechanisms at a cellular level: a rationale for clinical use

Delivery of health care demands evidence-based practice. Evidence-based practice helps to ensure that all facets of health care delivery are subject to a higher level of accountability. This helps to assure that the patient is receiving treatment that has some proof of efficacy. In recent years, physiotherapy practice has been influenced by a swell of research which, in many cases, supports current practice and, in some cases, influences change of practice. Despite the fact that there is a significant increase in the numbers of clinical trials and reviews in Physiotherapy, including research in electromagnetic modalities and mechanical modalities, it is not uncommon for a practitioner to feel at a loss to answer, “Exactly how does this treatment work?” This paper will review the mechanisms of action of the most common electromagnetic modalities and provide a rationale as to why “pulsed” fields seem to produce more significant effects compared with continuous applications. It will be shown that significant tissue healing effects, particularly with the modality PEMF, are likely the result of increased activity in non-excitable cells. The reputation of electromagnetic modalities has suffered in recent years, likely due to a lack of understanding of mechanisms for action. In the literature, the understanding in this area has made considerable progress over the past ten years. This review will explain the science at a cellular level and suggest the potential mechanisms for action for the modalities with specific focus on PEMF.