A laser (light amplification of stimulated emission of radiation) is the artificial ray, which is monochromatic, coherent and directional. Laser light with wavelengths of between 600 and 1, 300nm is optimized the depth of penetration in human tissue and is therefore most commonly used in the clinical setting. Low reactive level laser therapy (LLLT), outputting laser light with less than 500mW power, have been recommended for use in rehabilitation because there is some evidence that this form of electromagnetic energy may be biostimulative, facilitate healing and reduce pain. LLLT activates the electron transport chain, increases ATP synthesis, and therefore cause the macrophage, fibroblast and lymphocyte activity. Some studied that LLLT changed the nerve conduction and regeneration and induced vasodilation, particularly of the microcirculation. LLLT is clinically useful in wound healing, musculoskeletal disorders and pain management. The irradiation points are symptomatic pain area, motor points, ganglion, meridian point and so on. Especially irradiation to stellate ganglion and acupuncture points is safe and effective to reduce pain and to improve the peripheral circulation in human. It is difficult to make definitive recommendations for the clinical application of LLLT in rehabilitation, so that we have to study and reveal the mechanism of LLLT effects.
