Introduction
The term laser is an acronym for light amplification by stimulated emission of radiation. The laser is monochromatic collimated and coherent. A laser is a device that produces this light. Some physical therapists use low-level laser therapy (LLLT) to treat various musculoskeletal conditions State of health. LLLT is a non-invasive light source therapy that produces a single wavelength of light. It does not emit heat or vibrate. It is also known as photobiology or biostimulation. LLLT is thought to affect the function of connective tissue cells (fibroblasts), accelerating the Repairs and acts as an anti-inflammatory agent. Lasers with wavelengths ranging from 632 to 904 nm are used to treat musculoskeletal disorders. Wavelengths between 660 nm and 905 nm have the ability to penetrate the skin and soft/hard tissues. This light has a great effect on pain Inflammation and tissue repair. [1]
An output power of less than 0.5 watts is classified as LLLT (Class III in the US), while lasers with an output power of less than 500 mW or 0.5 watts are called High Power Laser Therapy HPLT (Class IV in the US). HPLT generates heat on the skin surface due to its high power density (radioactivity). LLLTs are often referred to as “cold lasers” because they do not feel heat during treatment. [2]
Effects of LLLT
The effects of LLLT are important to physical therapy and make this tool useful for augmenting other treatments such as therapeutic exercise:
- Reduces inflammation: It can happen over hours to days. [1]
- Pain relief
- Accelerated tissue regeneration: LLLT stimulates cell proliferation of fibroblasts [3] keratinocytes [4] endothelial cells [5] and lymphocytes. [6] [7]
Physiotherapy
In physiotherapy, LLLT is used to relieve pain, accelerate tissue regeneration and reduce inflammation.
Conditions that are treated include
- Osteoarthritis of the knee and ankle
- Rheumatoid arthritis
- TMD [8],
- Shoulder impingement syndromes
- Hip or shoulder bursitis
- Low back disc degeneration
- Disc herniation
- Sciatica
- neuropathic pain. [9]
- Tendonitis
- Tennis elbow
- Plantar fasciitis
- Reduces volume and pain of lymphedema [10] [11]
Evidence
A 2017 systematic review and meta-analysis found LLLT to be an effective treatment modality for reducing pain in adults with musculoskeletal disorders. They also noted that adherence to the World Association for Laser Therapy (WALT) dosage improves efficacy. [12]
A 2017 review titled “Effective treatment options for musculoskeletal pain in primary care: a systematic overview of current evidence” concluded that the evidence for the effectiveness of laser treatment for shoulder pain or acute or chronic neck pain was inconclusive . About low knee pain Laser therapy may have additional benefits over exercise and/or surgery. [13]
Contraindications
Contraindications according to the Laser Therapy Association of North America are:
- Eyes: Do not point laser beam at eyes, everyone present should wear appropriate safety glasses.
- Cancer: Do not treat at any site of known primary cancer or secondary metastases unless the patient is undergoing chemotherapy, at which point LLLT can be used to reduce side effects such as mucositis. However, LLLT can be considered for palliative care in patients with advanced cancer.
- Pregnancy: Do not administer directly to a developing fetus.
- Epilepsy: Be aware that low frequency pulses of visible light (<30Hz) may trigger seizures in patients with photosensitive epilepsy. The reported side effects of LLLT were no different from those reported by patients exposed to the placebo device in the trial.
References
- ↑ Jump up to:1.0 1.1 Cotler HB, Chow RT, Hamblin MR, Carroll J. The Use of Low Level Laser Therapy (LLLT) For Musculoskeletal Pain. MOJ Orthop Rheumatol 2015;2(5): 00068
- ↑ Rehab Management Treating Pain with Low vs High-Power Lasers: What is the Difference? Published on April 4, 2019 Available from: http://www.rehabpub.com/2019/04/treating-pain-low-vs-high-power-lasers-difference/ (last accessed 25.6.2019)
- ↑ Frigo L, Fávero GM, Lima HJ, Maria DA, Bjordal JM, et al. Low-level laser irradiation (InGaAlP-660 nm) increases fibroblast cell proliferation and reduces cell death in a dose-dependent manner. Photomed Laser Surg 2010;28 Suppl 1: S151-S156.
- ↑ Basso FG, Oliveira CF, Kurachi C, Hebling J, Costa CA. Biostimulatory effect of low-level laser therapy on keratinocytes in vitro. Lasers Med Sci 2013 28(2): 367-374.
- ↑ Szymanska J, Goralczyk K, Klawe JJ, Lukowicz M, Michalska M, et al. Phototherapy with low-level laser influences the proliferation of endothelial cells and vascular endothelial growth factor and transforming growth factor-beta secretion. J Physiol Pharmacol 2013;64(3): 387-391.
- ↑ Agaiby AD, Ghali LR, Wilson R, Dyson M. Laser modulation of angiogenic factor production by T-lymphocytes. Lasers Surg. Med 2000;26(4): 357-363.
- ↑ Moore P, Ridgway TD, Higbee RG, Howard EW, Lucroy MD. Effect of wavelength on low-intensity laser irradiation-stimulated cell proliferation in vitro. Lasers Surg Med 2005;36(1): 8-12.
- ↑ Cavalcanti MF, Silva UH, Leal-Junior EC, et.al.Comparative Study of the Physiotherapeutic and Drug Protocol and Low-Level Laser Irradiation in the Treatment of Pain Associated With Temporomandibular Dysfunction. Photomed Laser Surg. 2016 Nov 29. [Epub ahead of print]
- ↑ Chen YT, Wang HH, Wang TJ, Li YC, Chen TJ. Early application of low-level laser may reduce the incidence of postherpetic neuralgia (PHN). J Am Acad Dermatol. 2016;75(3):572-7.
- ↑ Smoot B, Chiavola-Larson L, Lee J, Manibusan H, Allen DD. Effect of low-level laser therapy on pain and swelling in women with breast cancer-related lymphedema: a systematic review and meta-analysis. J Cancer Surviv. 2015;9(2):287-304.
- ↑ Carati CJ, Anderson SN, Gannon BJ, Piller NB. Treatment of postmastectomy lymphedema with low-level laser therapy: A double blind, placebo-controlled trial. Cancer 2003;98(6): 1114-1122.
- ↑ Clijsen R, Brunner A, Barbero M, Clarys P, Taeymans J. Effects of low-level laser therapy on pain in patients with musculoskeletal disorders: a systematic review and meta-analysis. Available from: https://www.ncbi.nlm.nih.gov/pubmed/28145397/ (last accessed 25.6.2019)
- ↑ Babatunde OO, Jordan JL, Van der Windt DA, Hill JC, Foster NE, Protheroe J. Effective treatment options for musculoskeletal pain in primary care: A systematic overview of current evidence. PloS one. 2017 Jun 22;12(6):e0178621. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5480856/ (last accessed 24.6.2019)