How Does Acupuncture Work?

Lately I have been getting a lot of students and fresh graduates asking me "what is the best course that I should take?" This question has always come up over the years. I have both, taken as a student, and taught as an instructor at many different courses over the years. However, my answer is always the same. Truly, it does not matter what kind of therapist you are, or what population you want to treat. The best course any therapist should take is the McMaster University Contemporary Medical Acupuncture Program: a neurofunctional treatment of pain with movement disorders.

In 2002, approximately 2 million American adults used acupuncture, this increased to 3 million in 2007, with the most common reason for seeking out treatment being chronic pain. Electroacupuncture mechanisms on inflammatory pain have been widely studied, and is well understood. This modality inhibits inflammatory and neuropathic pain at the peripheral, spinal and supraspinal levels. Below is a diagram displaying the physiologic effect that electroacupuncture has on the nervous system and inflammatory cascade.

Electroacupuncture is known to significantly decrease pain as studied in human and animal models. In addition, needling changes the biochemical make-up of local tissues. It increases oxygenation, lowers substance P and inflammatory mediators as well as restores ph. The effect that electroacupuncture has on pain is widespread. It can be broken down into three areas. The first, peripherally, electroacupuncture acts by inducing a local release in endogenous opioids (B-endorphin) which act to suppress nociception. This is accomplished through sympathetic nerve activation and activation of the hypothalamus-pituitary axis.

The second, at the spinal level, it is thought that electroacupuncture works through inducing several neurotransmitters including norepinephrine (NE), opioids and serotonin (5-HT) which work interactively to inhibit pain via descending inhibitory pathways (LC and NRM which stand for locus coeruleus and nucleus raphe magnus respectively) on afferent nerves.

Lastly, at the supraspinal level, electroacupuncture alleviates the affective dimension of pain through opioid-mediated inhibition of NMDA receptors in the anterior cingulate cortex. NMDA receptors are the main receptor for the primary excitatory neurotransmitter, glutamate, in the human brain. The physiologic response from electroacupuncture detailed above also becomes extremely relevant in the context of chronic pain and when considering central sensitization/spinal segmental sensitization.

Central sensitization is a process that represents plasticity of the somatosensory nervous system. The function of neurons in nociceptive pathways is enhanced via increases in membrane excitability, synaptic efficacy and reduced inhibition (see image below). The net effect of central sensitization is allodynia and hyperalgesia. This process is achieved through alteration of GABA (inhibitory) , NMDA and SP signaling pathways in the spinal cord, all of which are pathways that electroacupuncture has an effect on.

As always, there is a time and place for any type of treatment modality and every case needs to be treated differently clinically. The growing need for acupuncture and scientific evidence to support its use makes this method a very important one to learn. This is why I recommend people to take the McMaster University Contemporary Medical Acupuncture Program.

references 

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