Electro-acupuncture is found effective in reducing inflammation and pain. 
A review published in Anesthesiology - The Journal of the American Society of Anesthesiologists concludes that electro-acupuncture is more effective at the 2 - 10 Hz setting than the 100 Hz setting for the relief of inflammation and neuropathic pain. The investigators note that electro-acupuncture “blocks pain by activating a variety of bioactive chemicals through peripheral, spinal, and supraspinal mechanisms.”
Details reveal that electro-acupuncture activates natural endogenous opioids and other biochemicals that desensitize sensory receptors for painful stimuli (nociceptors). The researchers note that electro-acupuncture desensitizes “peripheral nociceptors and reduce(s) proinflammatory cytokines peripherally and in the spinal cord, and serotonin and norepinephrine, which decrease(s) spinal N-methyl-D-aspartate receptor subunit GluN1 phosphorylation.” This results in less pain and inflammation.
The reviewers note that electro-acupuncture demonstrates unique characteristics. Electro-acupuncture activates the nervous system differently in healthy conditions than when treating pain related conditions. In addition, the reviewers note that studies now “suggest that electroacupuncture, when combined with low dosages of conventional analgesics, provides effective pain management which can forestall the side effects of often-debilitating pharmaceuticals.”
Another new study entitled the Mechanisms of Acupuncture Analgesia notes that acupuncture analgesia is commonly used for pain management in cases of both acute and chronic pain. The researchers from the Department of Anesthesiology, University of California at Los Angeles; and the UCLA Medical Center and Orthopedic Hospital document that MRI (magnetic resonance imaging) and PET (positron emission tomography) have demonstrated connections between Traditional Chinese Medicine (TCM) acupuncture analgesia principles and modern medicine.
The researchers discovered that modern science can now quantify a connection between acupuncture analgesia, modern electro-acupuncture and biomedical science. They note that basic and clinical research has revealed, “There are correlations between acupuncture analgesia and the neural pathways such as afferent peripheral transduction and nerve transmission, ascending and descending modulation pathways, interpretation and central processing in the brain.” Acupuncture continuing education and research has revealed this and other important findings with advanced imaging and biochemical analysis technology.
New imaging techniques including fMRI (functional magnetic resonance imaging) and PET (positron emission tomography) “revealed varying levels of neural modulation throughout (the) central nervous system. ” Overall, they note that acupuncture has demonstrated that it is “beneficial in the management of acute and chronic pain.” As a result of these findings, the researchers suggest continuing acupuncture studies to further elucidate the biochemical mechanisms of acupuncture analgesia.
Electro-acupuncture Device
These new findings have been discovered while basic research now reveals that acupuncture points have distinct anatomical characteristics. CT (computerized tomography) scans now demonstrate that acupuncture points have distinct structural differences than surrounding areas. At the acupuncture points, microvascular densities with bifurcations “can be clearly seen around thick blood vessels” but non-acupuncture points showed few thick blood vessels and none showed fine, high density structures. The acupuncture points contained fine structures with more large blood vessels that are several dozen micrometers in size plus beds of high density vascularization of vessels 15-50 micrometers in size. This structure was not found in non-acupuncture point areas.
This type of imaging has only been made possible with major advances in CT technology. The researchers used state-of-the-art in-line phase contrast CT imaging with synchrotron radiation to get clear images of the microvascular structures. This eliminates artifacts, widens the field of view and significantly improves soft tissue imaging. Unique characteristics of acupuncture point structures has also been measured with MRIs, infrared imaging, LCD thermal photography, ultrasound and amperometric oxygen sensors.
In another interesting study, researchers used an amperometric oxygen microsensor to detect partial oxygen pressure variations at different locations. The researchers concluded that partial oxygen pressure is significantly higher at acupuncture points. Below are images from the study measuring the increase of partial oxygen pressure combined with an overlay of the local acupuncture point locations. The images map the Lung, Pericardium and Heart channels and their associated local points. Acupuncture points show high oxygen pressure levels and non-acupuncture points do not.
References:
Zhang, Ruixin, Ph.D.; Lixing Lao, Ph.D.; Ke Ren, Ph.D.; and Brian M. Berman, MD. "Mechanisms of Acupuncture–Electroacupuncture on Persistent Pain." Anesthesiology 120, no. 2 (2014): 482-503.
Lee, Annie D., and Eric Shen-Zen Hsu. "Mechanisms of Acupuncture Analgesia." In Acupuncture for Pain Management, pp. 73-85. Springer New York, 2014.
Author Affiliations:
1. Department of Anesthesiology, University of California at Los Angeles, Los Angeles, USA.
2. Pain Management Center, Santa Monica-UCLA Medical Center and Orthopedic Hospital, 1245 16th Street, Suite 225, Santa Monica, California, 90404, USA.
Mechanisms of acupuncture-electroacupuncture on persistent pain.
Zhang R, Lao L, Ren K, Berman BM.
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Electroacupuncture alleviates affective pain in an inflammatory pain rat model.
Zhang Y, Meng X, Li A, Xin J, Berman BM, Lao L, Tan M, Ren K, Zhang RX.
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Electroacupuncture inhibition of hyperalgesia in an inflammatory pain rat model: involvement of distinct spinal serotonin and norepinephrine receptor subtypes.
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Electroacupuncture suppresses hyperalgesia and spinal Fos expression by activating the descending inhibitory system. Li A, Wang Y, Xin J, Lao L, Ren K, Berman BM, Zhang RX. Brain Res. 2007 Dec;1186:171-9. Epub 2007 Oct 22.
Chenglin, Liu, Wang Xiaohu, Xu Hua, Liu Fang, Dang Ruishan, Zhang Dongming, Zhang Xinyi, Xie Honglan, and Xiao Tiqiao. "X-ray phase-contrast CT imaging of the acupoints based on synchrotron radiation." Journal of Electron Spectroscopy and Related Phenomena (2013).
Minyoung Hong, Sarah S. Park, Yejin Ha, et al., “Heterogeneity of Skin Surface Oxygen Level of Wrist in Relation to Acupuncture Point,” Evidence-Based Complementary and Alternative Medicine, vol. 2012, Article ID 106762, 7 pages, 2012. doi:10.1155/2012/10a6762.
