It might come as a surprise that pain is not unique to mammals. It is also ‘sensed’ in a wide range of living creatures such as leeches, nematode worms, sea slugs, fruit flies, fishes, amphibians, reptiles and birds. There is also a gradual addition of multiple pain mechanisms as the evolutionary tree ascends from simple sea creatures to bipedal primates.
There has been much written about the mechanism of acupuncture analgesia and the effectiveness of its use in pain management. Although pain encompasses physical sensations that are interpreted as unpleasant, pain is also influenced by psychological factors and physiological changes before it even becomes a part of our consciousness. The multiple effects of acupuncture in the context of pain are best explained by dividing them into the local tissue effects of needling and central nervous system effects (spinal cord and brain).
I. Local Tissue Effects
A. Splinter Effect
Piercing the epidermis and dermis causes slight damage to capillaries and other tissue causing local blood to move by vasoactive effects which reduces the perception of pain.
B. Mechanical Tissue Deformation
Piercing connective tissue below the dermis with manipulation of the needle generates many mediators of pain and inflammation.
C. Muscle Trigger Point Complexes
Muscle fiber pain can remain in a hyper-contracted state for long periods of time in order to protect damaged muscle fibers. By piercing the contracted muscle fiber, confined calcium is released and relaxes the contracted muscle fibers.
D. Other Local Tissue Effects
1. Cupping in Oriental medicine therapy causes hemorrhage to small surface capillaries initiating an infusion of new blood into the affected area.
II. Central Nervous System Effects
A. Spinal Cord Pain Processing‒The Gate Theory
1. Non-noxious stimulation (acupuncture) suppresses pain, or “closes the gate” to noxious (harmful or injurious) stimulation in spinal neurons.
2. Transcutaneous electrical nerve stimulation (TENS) and electro-acupuncture are modalities that are able to alter pain.
B. Spinal Cord Pain Processing‒Interneuron Activation
1. Under the influence of low-frequency electro-acupuncture, spinal cord releases enkephalin and dynorphin (neuromodulators) bind to opiate receptors, blocking pain transmission.
2. Reduces substance P release(a peptide that transmits pain signals from the sensory nerves to the central nervous system), as well as calcium ion flow into nerve cells which reduces pain transmission.
C. Brain Activation of Descending Mechanisms
1. Use of positron emission tomography (PET) and Magnetic Resonance Imaging (MRI) have revealed areas of the brain that become active under the influence of acupuncture.
Chinese medicine has been around for thousands of years. As more and more research is conducted to “prove” the science behind the Chinese medicine modality of acupuncture its popularity is growing exponentially in the West as an effective, affordable, low-risk option in the treatment of all levels of illness and in the support of optimal wellness.
Anita Alexandra, L.Ac., CH is an acupuncturist and Chinese herbalist with 16+ years of experience. She practices at Chiropractic Health and Acupuncture, 619 Main Street, Frisco. (970)668-3299 www.CHAfrisco.com