Acupuncture, how it works?

By passing through Qi, the vital energy that circulates in every living organism. We go through the philosophy of Yin and Yang, dark and light energy and side, we come to the scientific justification and the answer to the question of how acupuncture works. And in fact, how effective it is in the treatment of acute and chronic pain. 

In recent years, clinical studies, veterinary and human, have already been available, which prove the effectiveness of acupuncture through various research methods. The placement of needles at certain acupuncture points stimulates the peripheral nervous system, and hence the central nervous system. The acupuncture analgesic effect can conceptually be divided into three segments: local, segmental (brain), and suprasegmental (spinal cord), and don’t forget the excreted endogenous opioids and inflammatory suppressants. 

But let's start from the beginning. What are acupuncture points? 

They have a specific anatomical location that corresponds to places with a high concentration of nerve endings, small blood and lymphatic vessels, and immunomodulatory cells, such as mast cells. Many acupuncture points are near regions that generate pain and muscular dysfunction, which include musculotendinous junctions, myofascial trigger points, and muscle motor points. 

And what happens when we insert the needle? 

The local effect it causes is a reaction of all the structures that are located at the given point. These are blood vessels, immunomodulatory cells, and afferent nerve endings that respond to touch, pressure, pain, and chemical changes; muscles; glands; and connective tissues, all contribute to its effects. These structures interact with the acupuncture needle near the insertion site and the nervous system is stimulated both locally and distally. When we stick the needle in and manipulate it, we get something like gluing the local tissue to the needle. Collagen and elastin fibers wind around the needle which leads to deformation of the local collagen matrix. Stimulation of nerve endings causes a cascade of cytokine release, activation of mast cells, and vasodilation in response. Deeper insertion of the needle also leads to a more intense reaction. Acupuncture stimulates the local release of endogenous opioids from lymphocytes, macrophages, and granulocytes within the surrounding tissues. These opioids act on peripheral nerve receptors within the tissue to suppress the propagation of nociceptive signals. When using electroacupuncture of different frequencies, the effect of separation of different endogens is enhanced. Beta-endorphin, encephalin, and orphanin release can be observed following a low-frequency stimulation (2-4 Hz), whereas serotonin and norepinephrine release is observed after higher frequencies (80–100 Hz). 

During embryogenesis, the segments of the spinal cord and spine develop in close synchrony, which explains how the nerves and roots of each segment of the spinal cord are distributed between the spine. As the somatic dermatome (an area of skin innervated by one segment of the spinal cord) expands over the surface of the body, its initial segmental innervation is maintained. There is a significant overlap of the peripheral nerves in these skin areas. Because of this connectivity through shared innervations, each part of an individual segment has the potential to modulate other parts of the same segment. Acupuncture provokes many antinociceptive effects at the level of the spinal cord. The activity of NMDA receptors, which play an important role in modulating chronic and pathological pain, is reduced. This activation results in a larger, more painful response to stimuli by changing the threshold for firing nerves. 

Because of this effect, acupuncture has great potential in treating chronic pain. Another important receptor in the management of chronic pain is GABA, which serotonin successfully manages to influence. Segmental analgesia in connection with pain relief can have a good effect on muscle tone, improve movement, and, accordingly, dew and heal. Segmentally, somatic and visceral afferent information are collected in the dorsal horn. The "directional pain" that can originate in an abdominal organ can be perceived as arising from the musculature of the abdominal wall, which is delivered by the same segmental innervations. Visceral pain can be suppressed by reversing this process by stimulating appropriate somatic receptors at the same segmental level, which is most useful if it is not possible to use local acupuncture points. The visceral nociception of "directed pain" has a dermatomal distribution and the surface of the body is well-mapped in humans to represent the areas of pain associated with the different visceral organs. 

Acupuncture also has its effect through some changes in the CNS. The suprasegmental effects of acupuncture are thought to be due to the stimulation of a descending antinociceptive network that is projected from several regions of the brain to the spinal cord of the spinal horn. Brain areas include the hypothalamus, the dorsolateral prefrontal cerebral cortex, and cingulate gyrus, the ventral tegmental area of the midbrain and periaqueductal gray matter (PAG), the nucleus raphe magnus of the medulla, the locus ceruleus of the pons. 

It is well known that acupuncture works via noradrenaline and serotonin release at all dorsal horn segments and therefore overlaps with the segmental analgesic effects of acupuncture and reinforces both local and segmental analgesia. The central mechanisms of acupuncture analgesia could be beneficial to many conditions including anxiety, stress, and chronic pain, especially from orthopedic and neurologic conditions. 

Of course, there is much to say, but let it be for the next post about alternative pain management methods. In conclusion, we can safely say that acupuncture as an alternative method of pain management is an effective and safe method. And in combination with electroacupuncture, the effect is quite satisfactory. In recent years, many studies have come out, mainly in human medicine, which use fMRI as evidence of the effectiveness and impact on the CNS. In veterinary medicine, there are also studies conducted with thermography, the purpose of which is the same. In other words, we have enough for evidence-based medicine.