What is an acupuncture point anyway?

imageAlina Tousseeva is a medical doctor who practiced as a surgeon in Russia, who came to Canada and now practices acupuncture at our clinic.  She is fascinated by the world of acupuncture and how it works. Read her blog on her research regarding the scientific description of an acupuncture point.

The mystery of the acupuncture point seems to be gradually resolving from a imagescientific point of view.  Evidence for the therapeutic effect of acupuncture is growing too, but what makes a given location on the body special from another regarding its ability to stimulate a healing response? This article today is mainly concerned with the common physical attributes that seem to be associated with acupuncture points.

We can imagine that the discovery of the first acupoints were those that produced strong reactions. In distant traditions, blind children were cultured toward practices like acupuncture, since their skills of touch were highly refined, and they could “see” with their fingers.  Acupuncture points have a certain “feel” to them, and it is my attempt to demystify from a scientific point of view what we acupuncturists are actually feeling when we probe to find the sweet spot we have come to learn as acupuncture points. 

How do acupuncture points feel?  Aside from often being in an anatomical depression, when palpated, they can be achy or sore.  They are prone to be sensitized by any damaged tissue of the body, since chemicals from the damaged site can accumulate here.  In this theory, the cause  of the soreness can be any injury, including infection, over muscle exertion, trauma injury, or biochemical/ hormonal imbalances, since they can cause an irritation of the acupuncture point area.

What makes an acupuncture point special? The fine cellular details alone cannot explain why acupuncture points are different.   However, medical researchers have noticed these points are associated with nerves and vessels in complex physical areas of potential restriction or transition. Let’s look at the nervous system more closely to understand this.

The neuron, an electrically charged cell, contains a cell body, an axon and dendrites (spindly arms).  It is a basic signalling unit of the nervous system. When dendrites are stimulated they generate electric signals (action potentials), which travel from dendrites located on the skin and muscles to the spinal cord and often to the brain. Acupuncture needles activate  not only the dendritic receptors of the sensory neurons,  they  also can affect the autonomic nervous system (ANS).  We do not have direct control over the ANS as with motor neurons, since they control all the basic functions of the body without any intention from you; things like blood vessels, heart, glands and gonads, and smooth muscles of digestion and the respiratory system. Information from the stimulated sensory receptors goes to the brain; on the other hand, if we stimulate  motor neurons or ANS neurons directly or indirectly we can cause a local muscle or a blood vessel response mimicking a brain signal. This means that local healing-therapeutic effect can be induced with acupuncture even if the brain is not involved.

In order be effective as an acupuncture point, the tissue must have one or more of the following characteristics (adapted from Dr. H.C. Dung; Physiology in Acupuncture. In “Anatomical Acupuncture”, Texas, San Antonio, 1997):

Acupuncture points:

  • are located at the sites where a nerve is emerging from one plane to another. Examples include: where a nerve changes from one layer of connective tissue to another (called fascial planes), usually moving closer to the surface. At or near holes in the  bone (called foramina), where the nerve is emerging under the skin. Where the nerve is branching or where they are connecting together.
  • are located where the motor nerves enter the muscle (motor points).
  • are located on the sensitive fibrous structures: eg. joint capsules, thick fascial sheets, collateral ligaments and muscle tendons. They are formed by the dense fibrous tissue and have abundance of sensory receptors.
  • are found along the neurovascular bundles, where arteries, veins, lymphatics, and the nerve are located close together and are covered by connective tissue. These are commonly places that bend, such as the knee, wrist, groin, neck, armpit and other joints.
  • are found along depressions on suture lines on the skull, which are associated with increased number or receptors and blood vessels.
  • are associated with an increased complexity of nerve bundles, representing a combination of ANS, sensory, and motor neurons. Eg; facial nerves along the trigeminal and facial nerve pathways. 
  • are located near the superficial nerves more often than on the deep nerves because they are more plentiful.

Next time, I’ll talk about theories that explain what is happening therapeutically when we put a needle into an acupuncture point and stimulate it.

Alina Tousseeva, M.D., R.Ac.