What is Low Level Laser Therapy

Low Level Laser therapy (LLLT) also known as Cold Laser Therapy or photobiomodulation, is a light therapy using lasers or LEDs to improve tissue repair, reduce pain and inflammation. Low level laser therapy has been used for many years on sports injuries, arthritic joints, neuropathic pain syndromes, back and neck pain.

How does it work: The Science

LLLT has a photochemical effect (like photosynthesis in plants). One of the main mechanisms of action occurs in the mitochondria (the cellular power plant inside every cell). It restores normal mitochondrial function, thus improving cell metabolism. When cells get stressed (due to disease or injury) the mitochondria produces nitric oxide (NO). This displaces oxygen from cytochrome c oxidase (a protein within the mitochondria), which reduces ATP (an essential intracellular energy and extracellular signalling molecule) and causes an over-production of reactive oxygen species (ROS). This leads to oxidative stress, which leads to inflammation and cell death (via the gene transcription factor NF-Kb). LLLT at the correct wavelength and density dissociates NO, allowing oxygen back in, so ATP is restored and oxidative stress is reduced. Once normal mitochondrial function is restored, then cell metabolism improves.

In simple terms, LLLT helps the patient to get better more quickly by aiding the healing process. It reduces pain, reduces inflammation, and improves wound tissue regeneration.

Does it Hurt?

No, not at all. There is some of the confusion regarding LLLT because of wide spread use of lasers in medicine and industry. There are a wide range of applications for laser technology in industry and medicine. LLLT has historically been classified as a non-thermal modality. Non-thermal modalities are those physical agents that do not raise the subcutaneous tissue temperature greater than 36.5ºC.

The Evidence

In an ever-growing field of interventions for pain and inflammation, LLLT has a very strong evidence base. There are over 200 randomised clinical trials that have been published on LLLT, half of which are on pain.
BMJ LLLT for chronic non-specific low back pain: a systematic review and meta-analysis of randomised controlled trials found "moderate quality of evidence" and "clinically important benefits" in the short term.

• Low-level laser therapy for chronic non-specific low back pain: a meta-analysis of randomised controlled trials. Glazov et al. Acupuncture Med. 2016 Oct;34(5):328-341

BMJ sports medicine journal, systematic review of surgical and conservative interventions for frozen shoulder found "strong evidence" for LLLT.

• Frozen shoulder: the effectiveness of conservative and surgical interventions--systematic review. Favejee, Huisstede, Koes. Br J Sports Med. 2011 Jan;45(1):49-56

The BMJ clinical evidence recommendations for tennis elbow 2011 now include LLLT

• Tennis elbow. Bisset, Coombes, Vicenzino. BMJ Clin Evid. 2011 Jun 27;2011.

American Physical Therapy Association guidelines recommend LLLT for Achilles tendonitis.

• Achilles Pain, Stiffness, and Muscle Power Deficits: Achilles Tendinitis. Carcia et al. J Orthop Sports Phys Ther. 2010:40(9)

Lancet systematic review: "LLLT reduces pain immediately after treatment in acute neck pain and up to 22 weeks after completion of treatment in patients with chronic neck pain".

• 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. Chow R. Lancet. Volume 374, No. 9705, p1897–1908, 5 December 2009

World Health Organisation (Bone and Joint Task Force) for neck pain Low Level Laser Therapy "more effective than no treatment, sham, or alternative interventions"

• The Bone and Joint Decade 2000–2010 Task Force on Neck Pain and Its Associated Disorders.Haldeman et al. Spine: 15 February 2008 - Volume 33 - Issue 4S - pp S5-S7