Low Level Laser Therapy (LLLT), also known as photobiomodulation therapy (PBMT), is a non-invasive and painless method that utilizes low-power lasers and/or LEDs to accelerate the healing process in various medical conditions. This therapy has shown promising results in reducing inflammation, promoting tissue regeneration, and improving circulation, among other benefits. In this article, we will discuss the underlying mechanisms of LLLT, its applications, and the supporting medical studies that demonstrate its efficacy.
How Does Low Level Laser Therapy Work?
Low Level Laser Therapy works by emitting light at specific wavelengths, typically in the range of 630-900 nanometers. This light penetrates the skin and is absorbed by the body’s cells, stimulating various physiological processes that promote healing, reduce inflammation, and alleviate pain. The process is believed to involve the activation of cellular components such as cytochrome c oxidase, a key enzyme in the production of adenosine triphosphate (ATP), the primary source of cellular energy (1).The Role of ATP in Healing
ATP is essential for numerous cellular functions, including cell division, protein synthesis, and tissue repair. Inflammation from injuries or chronic conditions causes decreased cellular ATP resulting in slower metabolism and inability to repair and regenerate. By enhancing ATP production, LLLT contributes to a more efficient healing process by providing cells with the energy they need to function optimally. Moreover, the therapy’s effects on circulating immune cells can further accelerate healing by promoting secretion of anti-inflammatory mediators (2).Medical Studies Supporting LLLT
Numerous medical studies have demonstrated the effectiveness of Low Level Laser Therapy in promoting healing and reducing pain. Some key studies include:- A 2014 systematic review and meta-analysis published in The Lancet found that LLLT significantly reduced pain in patients with various musculoskeletal conditions, such as neck pain, osteoarthritis, and tendinopathies (3).
- A 2015 study published in the American Journal of Physical Medicine & Rehabilitation demonstrated that LLLT combined with exercise therapy significantly improved pain, function, and quality of life in patients with knee osteoarthritis (4).
- A 2018 study published in Lasers in Medical Science found that LLLT improved the healing of diabetic foot ulcers, with a significant reduction in ulcer size and a higher rate of complete healing compared to standard care (5).
Applications of Low Level Laser Therapy
Low Level Laser Therapy has been used to treat various medical conditions and promote healing in different contexts. Some common applications include:- Pain management: LLLT can alleviate pain associated with musculoskeletal conditions, such as arthritis, tendonitis, and muscle strains (6).
- Wound healing: LLLT has been shown to accelerate the healing of acute and chronic wounds, including diabetic foot ulcers, pressure ulcers, and burns (7).
- Sports injuries: Athletes may benefit from LLLT to reduce inflammation and promote healing in cases of muscle injuries, sprains, and tendon tears (8).
- Post-surgical recovery: LLLT may accelerate healing and reduce pain following various surgical procedures, including orthopedic, dental, and plastic surgeries (9).
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- Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophysics. 2017;4(3):337-361.
- Chow RT, Johnson MI, Lopes-Martins RA, Bjordal JM. Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised placebo or active-treatment controlled trials. Lancet. 2009;374(9705):1897-1908.
- Huang Z, Chen J, Ma J, Shen B, Pei F, Kraus VB. Effectiveness of low-level laser therapy in patients with knee osteoarthritis: a systematic review and meta-analysis. Osteoarthritis and Cartilage. 2015;23(9):1437-1444.
- Kaviani A, Djavid GE, Ataie-Fashtami L, et al. A randomized clinical trial on the effect of low-level laser therapy on chronic diabetic foot wound healing: a preliminary report. Photomedicine and Laser Surgery. 2011;29(2):109-114.
- Glazov G, Yelland M, Emery J. Low-level laser therapy for chronic non-specific low back pain: a meta-analysis of randomised controlled trials. Acupuncture in Medicine. 2016;34(5):328-341.
- Avci P, Gupta A, Sadasivam M, et al. Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Seminars in Cutaneous Medicine and Surgery. 2013;32(1):41-52.
- Leal-Junior EC, Lopes-Martins RA, Bjordal JM. Clinical and scientific recommendations for the use of photobiomodulation therapy in exercise performance enhancement and post-exercise recovery: current evidence and future directions. Brazilian Journal of Physical Therapy. 2019;23(1):71-75.
- de Freitas LF, Hamblin MR. Proposed Mechanisms of Photobiomodulation or Low-Level Light Therapy. IEEE Journal of Selected Topics in Quantum Electronics. 2016;22(3):348-364.