A Systematic Literature Review of Complementary and Alternative Veterinary Medicine: Laser Therapy

SIMPLE SUMMARY: Light therapy, or photobiomodulation, is a collective name for methods where tissue is irradiated with different types of light, with the aim of stimulating healing. The group includes methods such as laser, Light Emitting Diode (LED) light, ultra and infrared light, and tanning beds. In animals, the main indications for light treatment are musculoskeletal injuries, neurological diseases, wounds, and pain. Despite being frequently used, there is no consensus regarding the optimal treatment protocols for light therapy nor its clinical efficacy. Therefore, the aim of this systematic review was to evaluate the documented clinical effects of light therapy, with a focus on laser and LED light, in horses, dogs, and cats. The undertaken systematic literature review found gaps in the scientific documentation. Conflicting study results and unclear application for clinical use are explained by the wide variety of treatment parameters used in the analyzed studies, such as wavelength, laser class, dose, and effect, as well as the frequency and duration of treatment. Some beneficial effects have been reported during treatment with light therapy; however, the published studies also have limited scientific quality regarding these therapies, with a high or moderate risk of bias. ABSTRACT: Light therapy, or photobiomodulation, is a collective name for methods where tissue is irradiated with different types of light, with the aim of stimulating healing. Despite being frequently used, there is no consensus regarding the optimal treatment protocols for light therapy, nor its clinical efficacy. A systematic literature review was conducted, searching the relevant literature regarding light therapy in three databases, published between 1980–2020. The risk of bias in each article was evaluated. Forty-five articles met the inclusion criteria; 24 articles were regarding dogs, 1 was regarding cats, and the rest were regarding horses. The indications for treatment were musculoskeletal and neurologic conditions, skin disease and wounds, and pain. The literature review showed conflicting study results and unclear application for clinical use. This can be explained by the wide variety of treatment parameters used in the searched studies, such as wavelength, laser class, dose, and effect, as well as the frequency and duration of treatment. Although some beneficial effects were reported for light therapy, the studies also had limited scientific quality regarding these therapies, with a high or moderate risk of bias.