How it works, what it treats, and why it is a good choice for treating pain.
Acupuncture and Mainstream Medicine
Acupuncture is currently recommended for the management of chronic or sub-acute low-back pain by both the American College of Physicians and the American Pain Society. As research data supporting the use of acupuncture continue to mount, acupuncture is recommended for more conditions each year. It is no longer an "alternative" or a "complement," it is just another option. We have several large randomized controlled trials(1) and meta-analyses(2) demonstrating acupuncture to be a more effective treatment for several types of chronic pain than standard care (drugs, surgery, physical therapy). In fact, recent meta-analyses show that acupuncture is effective for a wide range of complex conditions.(4) Here is an exerpt from a well-written article on Medscape discussing the importance of adding acupuncture to standardized treatment guidelines:
"A more rational approach would be to recognize the potential role of acupuncture earlier in the treatment of potentially disabling and chronic illnesses. An example would be its use earlier in the treatment of low back pain, perhaps at the critical juncture of between 6 and 8 weeks, when acute back pain often starts to convert to chronic back pain. Starting earlier in the chain of treatment may reduce the cost of expensive evaluations, can lower the burden of patient suffering, and might improve back-to-work statistics."
Known Mechanisms of Action—How it works.
Acupuncture is, essentially, a therapeutic procedure that "hacks" into the nervous system to get it to do things it is designed to do, but is failing to do for one reason or another. It does this by "setting off alarms" in your nervous system without really doing any damage. This elicits a strong pain-killing repair response from your central and peripheral nervous system. Acupuncture triggers the nervous system in ways that no other intervention can—no drug, physical therapy, or surgery can do the things acupuncture can do. Though most people promote acupuncture as an ancient healing intervention, modern acupuncture is more accurately conceived as a cutting edge, minimally invasive, extremely safe procedure to effect changes in local connective tissues and neurophysiology. If we look at the amazing research happening now, we can see that acupuncture has a future that is even more impressive than its past.
Local Effects of Therapeutic Acupuncture
Local neuropeptide release: Acupuncture needles are inserted just under the skin and into muscles to stimulate what is called an axon reflex in order to trigger the release of several different neuropeptides that cause vasodilation to increase local blood circulation. One of these neuropeptides (calcitonin gene-related peptide) also promotes the formation of new blood vessels—a big part of how acupuncture triggers, and promotes repair in injuries (5). Acupuncture is more than just pain control. The manipulation of the needle in the connective tissue beneath your skin also simulates fibroblast cells to trigger repair of local tissues (6,7). Precise needling of trigger points found in muscles releases the muscles, allowing them to relax and lengthen, which translates to better-functioning joints and less pain.
Extrasegmental Analgesia in Therapeutic Acupuncture
Extrasegmental analgesia is more dependent on the type of stimulation than on the location selected for treatment. Where segmental analgesia affects areas related to the site chosen for needling, extrasegmental effects affect your whole body simultaneously. This is because these effects are caused more by changes in your brain than in peripheral tissues at the site of needling. Acupuncture can selectively stimulate the release of neuromodulators (opioid peptides) in your brain (5,9,10). Different types of stimulation at the needle trigger the release of different peptides. These peptides have a strong pain-killing effect in your body—everywhere. This explains why acupuncture often improves aches and pains you may have never even mentioned to your doctor.
Central Regulatory Effects of Therapeutic Acupuncture
Some of the most cutting-edge acupuncture research uses functional magnetic resonance imaging (fMRI) to observe and study brain function during acupuncture (13). These studies have confirmed that acupuncture produces profound and complex changes in the brain—specifically, the limbic system. Most patients report a feeling of well-being, better sleep, better mood, etc. after acupuncture treatments. These changes are due to the effects of acupuncture on the brain. These changes are only just being explained scientifically, but have been observed and recorded by Chinese physicians for 2500 years. These brain changes may also explain how acupuncture is able to effect changes in disorders of the endocrine system and other highly complex physiological systems.
Important Clinical Trials & Meta-analyses
Showing effectiveness for various conditions:
Segmental Analgesia in Therapeutic Acupuncture
Local effects of therapeutic acupuncture may seem intuitive. However, acupuncture is very often performed at locations on your body nowhere near your pain. Why? The segmental analgesia model explains this aspect of acupuncture. You may have heard that acupuncture is based on a “life-force” flowing through invisible lines called “meridians.” This is a confused modern interpretation of observations made by Chinese physicians 2500 years ago (10,14). The idea that a needle in your foot can help your back pain was difficult to explain without a detailed understanding of the nervous system. We now know that many of the observations that seemed “magical” to early translators of Chinese classical texts can be explained by neuroscience.
Segmental analgesia is achieved by using an acupuncture needle to stimulate a particular type of nerve fiber, the A-delta fibers. Different nerve fibers have different functions in the body, and they are “wired” differently. When A-delta fibers are stimulated with an acupuncture needle, they activate a type of cell (intermediate cells) in the spinal cord, which in turn suppress the ability for C fibers to communicate pain to your brain. So, acupuncture can effectively block pain signals at specific spinal segments. Needle sites that are along the distribution of nerves from the target segment are chosen for treatment.
Acupuncture can regulate organ function in a similar way. The organs of your body are controlled by your brain and by reflexes in your peripheral nervous system. Acupuncture has been shown to manipulate both systems (5,9,10). Specifically, acupuncture modulates the autonomic reflexes at the spinal segments associated with the needling site.
This blocking effect affects all the nerve fibers at that level of the spinal cord and explains why acupuncture can be effective for so many kinds of pain and organ dysfunction. It also explains why specific locations are chosen for treatment.
The Neurophysiology of Acupuncture
The Evidence of Effectiveness & Efficacy
- Haake M, Müller H-H, Schade-Brittinger C, et al. GERAC German Acupuncture Trials for chronic low back pain: randomized, multicenter, blinded, parallel-group trial with 3 groups. Arch Intern Med. 2007;167(17):1892-1898.
- Manheimer E, White A, Berman B, Forys K, Ernst E. Meta-analysis: acupuncture for low back pain.Ann Intern Med. 2005;142(8):651-663.
- Vickers AJ, Cronin AM, Maschino AC, et al. Acupuncture for chronic pain: Individual patient data meta-analysis. Arch Intern Med. 2012;172(19):1444.
- Hempel S, Taylor SL, Solloway MR, et al. Evidence Map of Acupuncture. 2014.
- White A, Cummings TM, Filshie J. An Introduction to Western Medical Acupuncture. Edinburgh: Churchill Livingstone/Elsevier; 2008.
- Langevin HM; Churchill DL; Fox JR; Badger GJ; Garra BS; Krag MH. Biomechanical response to acupuncture needling in humans. Journal Of Applied Physiology (Bethesda, Md.: 1985) 2001;91(6):2471-2478.
- Langevin HM. What Does Basic Research Tell Us About the Effects of Acupuncture on Connective tissue? American Acupuncturist 2010;52:27-29.
- Langevin HM, Bouffard NA, Fox JR, et al. Fibroblast cytoskeletal remodeling contributes to connective tissue tension. Journal of Cellular Physiology 2011;226(5):1166-1175. doi:10.1002/jcp.22442.
- Stux G, Hammerschlag R, eds. Clinical Acupuncture: Scientific Basis. Berlin ; New York: Springer; 2001.
- Kendall, Donald E. Dao of Chinese Medicine: Understanding an Ancient Healing Art (2002)
- Shaozong, C. Modern acupuncture theory and its clinical application. (Chapter 5 The Morphologic Relationship between Points and Nerves). International Journal of Clinical Acupuncture. 2001;121(2):149-158
- Dung HC. Anatomical features contributing to the formation of acupuncture points. American Journal of Acupuncture. 1984;12:139-143
- Huang W, Pach D, Napadow V, et al. Characterizing acupuncture stimuli using brain imaging with FMRI--a systematic review and meta-analysis of the literature. Plos One. 2012;7(4):e32960-e32960. doi:10.1371/journal.pone.0032960.
- Unschuld PU. Huang Di Nei Jing Su Wen Nature, Knowledge, Imagery in an Ancient Chinese Medical Text, with an Appendix, the Doctrine of the Five Periods and Six Qi in the Huang Di Nei Jing Su Wen. Berkeley: University of California Press; 2003. http://search.ebscohost.com/login.aspx?direct=true&scope=site&db=nlebk&db=nlabk&AN=90504. Accessed April 18, 2014.