Efficacy of Photobiomodulation Therapy in the Treatment of Pain and Inflammation: A Literature Review

Abstract

The main objective of this literature review was to analyze the efficacy of (PBM) therapy application on subjects with chronic pain and inflammation, and furthermore, to evaluate the methodological quality of the collected literature. The search was conducted using five databases: PubMed, ProQuest, Scopus, Web of Science, and PEDro. The keywords “low level laser therapy”, “chronic pain”, and “inflammation” provided the selection of RCTs that were published within the last 5 years, conducted in humans, and written in English. The PEDro Internal Validity Scale (IVS) checklist was used to evaluate the risk of bias in the included studies. A total of 11 articles were selected, all of them RCTs. Of the articles, five showed that PBM positively influences chronic pain, while another showed the same but only in the short term. In two other articles, the patient’s inflammation improved markedly. In one article there was no improvement in chronic pain and in another, there was no improvement in inflammation. Four articles demonstrated that PBM is beneficial in acute pain. Furthermore, six studies were given an “excellent” score and the remaining five a “good” score based on the IVS. Photobiomodulation has beneficial effects on chronic pain and inflammation, although more research needs to be completed in this line for this to be clarified as the existence of RCTs on this subject is limited.

Devices used for photobiomodulation of the brain—a comprehensive and systematic review

“…Photobiomodulation (PBM) is a non-invasive therapy that entails the use of red to infrared (IR) light (wavelengths of 600 to 1100 nm) to stimulate cellular processes that promote tissue healing and regeneration [ 1 – 3 ]. Additionally to being studied and used as a therapy for pain relief [ 4 , 5 ], wound healing and skin rejuvenation [ 6 , 7 ], the neuromodulation effects of PBM, when applied to the scalp, have been increasingly more studied, with several clinical studies showing that it could be a safe, non-invasive, and non-destructive alternative to conventional treatments for various neurological disorders.…”

Relationship between Laser Intensity at the Peripheral Nerve and Inhibitory Effect of Percutaneous Photobiomodulation on Neuronal Firing in a Rat Spinal Dorsal Horn

“…Although the mechanism is not fully understood [2][3][4][5]21,22], previous studies using electrophysiological techniques have shown that PBM affects the activity of paintransmitting nerves [23][24][25][26][27][28][29]. These include a few studies in which neural activity was recorded in the spinal dorsal horn, the entry point for pain signals in the central nervous system [30], but these studies do not mention the Rexed laminae of the spinal dorsal horn [28,29].…”

Low-power red laser and blue LED on circadian gene mRNA levels in human breast cancer cells

“…Low-power light-emitting diodes (LEDs) and lasers are devices that emitted radiations with clinical applications, such as pain relief, wound healing, treatment of acne and anti-inflammatory activity based on the photobiomodulation (PBM) process [1][2][3][4]. Lasers are able to emit monochromatic, * Author to whom any correspondence should be addressed.…”