Pulsed electromagnetic fields improve the healing process of Achilles tendinopathy

Abstract

Aims In the context of tendon degenerative disorders, the need for innovative conservative treatments that can improve the intrinsic healing potential of tendon tissue is progressively increasing. In this study, the role of pulsed electromagnetic fields (PEMFs) in improving the tendon healing process was evaluated in a rat model of collagenase-induced Achilles tendinopathy. Methods A total of 68 Sprague Dawley rats received a single injection of type I collagenase in Achilles tendons to induce the tendinopathy and then were daily exposed to PEMFs (1.5 mT and 75 Hz) for up to 14 days - starting 1, 7, or 15 days after the injection - to identify the best treatment option with respect to the phase of the disease. Then, 7 and 14 days of PEMF exposure were compared to identify the most effective protocol. Results The daily exposure to PEMFs generally provided an improvement in the fibre organization, a decrease in cell density, vascularity, and fat deposition, and a restoration of the physiological cell morphology compared to untreated tendons. These improvements were more evident when the tendons were exposed to PEMFs during the mid-acute phase of the pathology (7 days after induction) rather than during the early (1 day after induction) or the late acute phase (15 days after induction). Moreover, the exposure to PEMFs for 14 days during the mid-acute phase was more effective than for 7 days. Conclusion PEMFs exerted a positive role in the tendon healing process, thus representing a promising conservative treatment for tendinopathy, although further investigations regarding the clinical evaluation are needed. Cite this article: Bone Joint Res 2020;9(9):613–622.

Pulsed Electromagnetic Fields Induce Skeletal Muscle Cell Repair by Sustaining the Expression of Proteins Involved in the Response to Cellular Damage and Oxidative Stress

“…The choice of the intensity of 1.5 mT for pulsed electromagnetic fields (PEMF) stimulation is particularly significant in light of the results observed in other studies. It was, in fact, observed that this specific intensity was actually able to stimulate anabolic processes and limit the catabolic effects of IL-1β in chondrocytes [37], to improve the proliferation and expression of tissue-specific markers in osteoblasts [38,39], and to improve fiber organization, with a decrease in cell density, vascularity, and fat deposition [25]. Finally, stimulation with PEMF at an intensity of 1.5 mT promotes the differentiation and proliferation of myoblasts, through the activation of TRP channels and the influx of calcium into the cells, highlighting their crucial role in facilitating myogenesis [19].…”

“…PEMF stimulation at a 1.5 mT intensity and a frequency of 75 Hz has been shown to be effective in the activation of various cellular processes. Specifically, recent studies reported significant enhancements in cellular proliferation, differentiation, anti-inflammatory activity, and regeneration in response to 1.5 mT PEMF [23][24][25][26].…”

Developmental endothelial locus-1 attenuates palmitate-induced apoptosis in tenocytes through the AMPK/autophagy-mediated suppression of inflammation and endoplasmic reticulum stress

“…Finally, the present study provides a basis for developing therapeutic agents for tendinopathy in patients with obesity or insulin resistance by stimulating muscle DEL-1 secretion through regular exercise or by administration of DEL-1. Moreover, t will be more effective if the use of DEL-1 is additionally considered in the previously reported treatment methods 40 - 43 for musculoskeletal disorders.…”

Effect of the low-intensity pulsed ultrasound therapy on healing of Achilles tendinopathy in a rat model

“…Based on the ultrasound mechanism of action proposed in the literature, 4 it was discovered that the differential effect of treatment time difference may be noticeable in groups that began in the proliferative phase. 8 As a result, the groups with mid-acute phase commencement of treatment were separated into 3 subgroups with treatment durations ranging from 7 to 14 days.…”