Laser therapy – treatment using low-energy laser light – has been used in medicine since 1964 and is a natural continuation of work in the field of the biological effects of monochromatic light radiation (photochromotherapy). The first scientific and clinical substantiation of the application of narrow spectra of visible light for the treatment of various diseases, including orthopedic, was carried out by N. Finsen at the end of the last century. In 1898, he developed an apparatus for obtaining “pure” red light using a ruby filter, a treatment method, organized an institute and a clinic for phototherapy for patients, and also based on empirical observations formulated the basic principles of phototherapy that are still valid until now: the dependence of the therapeutic effect on the radiation spectrum and the degree of its monochromaticity (the narrowest possible spectrum of radiation), high biological activity of red light for the treatment of chronic pathological processes, a decrease in therapeutic efficiency in the presence of extraneous light sources. The therapeutic effect was explained by an increase in the body’s resistance. Finsen’s works were recognized (in 1903 he was awarded the Nobel Prize) in all European countries, including Russia, where light therapy rooms were opened and successfully operated in large cities. The complexity and imperfection of the design of the phototherapy apparatus, combined with the successes of pharmacology and pharmacy, led to the oblivion of the Finsen method by practical medicine. The development of radiation genetics and the discovery by A. Kellner (1949) of the effect of photoreactivation – restoration of the damaged genetic structure of a cell by light radiation, was the first theoretical substantiation of the biological effect of phototherapy.
The experience of studying the biological effects of monochromatic radiation (radiation with a narrow spectral region) at the Kazakh State Institute, as well as the invention of fundamentally new light sources of lasers, the radiation of which, in addition to a high luminous flux density, is characterized by a narrow radiation spectrum (within the wavelength) and polarization, were the basis for the use of laser light to stimulate physiological processes. Traditionally, for therapeutic purposes, laser radiation in the red spectral region (ISS) has been used.
Thus, laser therapy appeared at the “junction” of at least two remarkable discoveries: the effect of photoreactivation and photochromotherapy, as well as optical quantum generators – lasers. Currently, laser therapy, as a special branch of medicine, is successfully used in almost all of its areas and is officially recognized by all developed countries. Considerable experience of its clinical application has been accumulated and the mechanism of the biological action of laser light has been sufficiently studied.
For the treatment of orthopedic-surgical patients, low-intensity laser radiation in the red spectrum has been used for more than 30 years. As a source of light energy, helium-neon lasers with a radiation power of 10-25 mW are usually used. At CITO, systematic studies on the study of the mechanism of the implementation of laser light and aspects of its clinical application have been carried out since 1974 and have a priority character both in domestic and foreign medicine.
The data of domestic and foreign researchers, as well as clinical and experimental studies and a large positive experience in the practical application of the ISS laser in an outpatient setting (in more than 20 thousand patients over the past 15 years) allowed us to formulate a mechanism for the implementation of the therapeutic effect of low-intensity light radiation.
When analyzing numerous publications on the problem of the mechanism of biological action (the number of which exceeds about 1000 per year), the most significant are: the ability of certain doses of ISS to reduce ATPase activity and increase the concentration of ATP; to reduce the intensity of lipid peroxidation due to the activity of anti- peroxide protection enzymes, which prevents the violation of the barrier function of ischemic membranes; activate the fibrinolytic activity of the blood. This, in turn, significantly increases the antioxidant properties of the blood and increases the body’s resistance.
Studies of the effect of various doses of laser light on dystrophically altered muscle tissue carried out jointly with the staff of the Laboratory of Experimental Traumatology of CITO, carried out using quantitative morphometric methods of light (the method of optical-polarization analysis by E.F. Uratkova) and electron microscopy, indicate the dependence of the biological effect of ISS lasers on the applied radiation parameters. The positive effect of laser therapy is due to a decrease in indicators of membrane instability and paranecrosis of myions and has a circulatory-metabolic orientation. An increase in the volume of mitochondria, the number of pinocytic vesicles of capillaries was noted, which indicates a positive effect on energy processes in the muscle cell, which creates conditions for the removal of the focus of alteration of excitable tissues from the exaltacillary phase of parabiosis – the antiparabiotic effect of ISS (according to the theory of parabiosis by N.E. Vedensky – V.D. Vasiliev).
Under the influence of the ISS on the peripheral nervous system, its ability to increase the threshold of excitability was revealed, to create a state of “operative rest” (according to A.A. Ukhtomsky, 1958), which is characterized by increased metabolic processes (due to activation of sympathetic regulation) and an analgesic effect. According to our data, skin temperature is the main indicator of the level of tissue blood flow, and the threshold of pain perception increases only at certain exposure doses of radiation). The results of clinical and physiological studies indicate the normalizing effect of laser therapy on the state of sympathetic and parasympathetic innervation, tissue and capillary blood flow (an increase in the number of unchanged capillaries, a decrease in erythrocyte aggregation and increased capillary permeability). The course use of ISS has a pronounced effect on the coagulation and anticoagulation systems of the blood, eliminating hypercoagulable syndrome and activating fibrinolysis.