Sunday, November 13, 2016
Laser: The Power of Light
Laser: The Power of Light
Sure, most people know that heat and ice can help with injuries; others may even be aware of the use of electrical stimulation and ultrasound. However, did you know that light can also help with the healing process? Now, this doesn’t mean that you can hold your hurt foot next to a lamp and expect it to completely fix it. This type of modality requires a specific type of light or laser. This ‘light spectrum encompasses ultraviolet, visible, and infrared energy”1 to produce photochemical effects. Lower-level laser therapy (LLLT) is a non-traditional type of modality that can be used to normalize certain cellular operations. Lower-level laser therapy has been used around the world since the early 70’s and only recently made its debut in the United States in the early 2000’s. Although there are is not much information of the exact mechanism of laser, there are many positive effects and benefits to this modality.
Laser can produce healing through the use of photons. “Evidence has shown that photons emitted from LLL with the wavelengths in the red and near-infrared range are capable of stimulating receptors in biological tissues”2, and this creates therapeutic benefits. There are five types of therapeutic lasers which include argon (Ar), gallium-arsenide (GaAs), gallium aluminum arsenide (GaAlAs), helium-neon (HeNe) and indium gallium aluminum phosphate (InGaAlPO4). The three most common types are HeNe, GaAlAr and GaAs.
When it comes to laser there are three different responses that lead to three different outcomes of healing. Facilitatory response increases ATP synthesis which leads to an increase in cell metabolism, cell proliferation, enzyme activity, etc. This type of reaction will result in tissue repair. Inhibitory response reduces intracellular pH and COX production which brings about a reduction in inflammation. The last response is an indirect effect (increased blood flow, enhance lymph circulation, deposition of granulation tissue) which ties into the inhibitory response to create a decrease in pain.
With all of that being said laser can be used for wound/fracture healing, arthritis, acute/chronic inflammation and myofascial/musculoskeletal pain. Contraindications (reasons to not use laser) would include application over the eyes, over areas of active DVT (deep vein thrombosis), cancerous spots, etc. Although laser is not as popular as stim or ultrasound and there is a lack of literature, there is still evidence that proves that it can be effective in the training room.
1 Starkey, C., & Starkey, C. (2013). Therapeutic modalities (4th ed.). Philadelphia: F.A. Davis.
2 McLeod, I. A. (2004). Low-Level Laser Therapy in Athletic Training. Athletic Therapy Today, 9(5), 17-21.
Laser Therapy for Elite Athletes. (n.d.). Retrieved November 13, 2016, from http://physical-therapy.advanceweb.com/Features/Articles/Laser-Therapy-for-Elite-Athletes.aspx