Acupuncture through the eyes of an anatomist
When I think about process, I can’t help reflecting upon how differently I see my patients now from what I saw before I studied anatomy. When I first qualified as an acupuncturist, the only map that we used for navigating the human body – understanding physiology and deciding which points to use – was the map of acupuncture meridians and point classifications.
Looking at the body in this way worked just fine for me, and I happily trod in the footsteps of my acupunctural forbears – both five element and TCM. The ‘suspension of disbelief’ required – to work solely within the realms of an interpretation of the body that had no correlate in modern anatomical or medical understanding – was made straightforward for me by the simple fact that my patients got better.
Looking beneath the surface
But in the early 2010s, it became possible for the first time for complementary health practitioners to study anatomy in the medical way – through direct examination of individuals who had donated their mortal remains to medical science. The head of anatomy at St George’s medical school was the first person to allow practitioners from outside western medicine to come and learn from bodies in this way. I jumped at the opportunity, wanting to learn as much as I could.
My self-imposed studies culminated in a week-long course where we performed the dissection ourselves. I was confronted with the connective tissue known as fascia that surrounds every structure in the body – separating it from its neighbours, allowing muscles to slide over each other, and connecting every aspect of the human body together.
The fascia also acts almost like a second skin. On the surface you have the familiar layer of skin with fat underneath – then inside you have a second complete sheath of white fascia that covers and contains all your muscles and organs, from the top of your head down to the tip of your toes.
Before doing that course, I had no idea that there was a physical substance that both connected and defined every single structure of the body small and large – a substance that also forms a complete internal protective layer. Anatomy books and pictures all have the fascia removed; the same goes for teaching prosections – that is, smaller specimens that have been dissected by an anatomist to allow you to see the structures, muscles, nerves, blood vessels, etc within them.
Of course, the concept of a substance that flows throughout the body was very familiar to me – as qi – and the idea that there was a protective layer that ran underneath the skin was also very familiar – as wei qi. These similarities hit me with a force of deep revelation and thus arrived my anatomical eureka moment!
Overlaying ancient and modern
Since that first dissection, I have been investigating the possibility that the map of meridians and acupuncture points that I use to understand the body and to treat people with acupuncture is rooted in the visible human body. My research has focused on the texts of the early physicians who wrote about acupuncture in the Classics over 2000 years ago. I have taken the standpoint of seeing them as anatomical texts, and this is now what informs my view of acupuncture.
To return to the question of process; when we learn how to find acupuncture points on each other at college, we are looking for gaps and depressions in flesh that have a distinctive feel to them. The meridians themselves are also usually palpable as naturally occurring channels found in the spaces between muscles and/or bones.
For example, if I start at the base of my thumb and run my finger up along the bone on the inside of my forearm – the radius – I can feel a space where on one side there is bone and on the other side is muscle. That is where the lung meridian runs. Similarly, on the back of the forearm, I can run my finger in the space that is formed between the two forearm bones – radius and ulna – where the triple heater meridian runs. And so on.
Now, when you look at the forearm with the skin removed you can quite clearly see the muscle groups that are contained within their fascial sheaths, and how they exist in relation to the bone that they run alongside. The fascia both connects neighbouring structures together and forms the boundaries between them. In these gaps – or fascial planes – run the nerves, arteries and veins of the body. These are also inside a fascial sheath, covering not only the individual nerves or blood vessels, but also the entire neurovascular bundle.
The majority of acupuncture points lie in the fascial planes of the body, and so coincide with nerves, arteries or veins – and sometimes all three. This is inherent given the way that the body is organised. As an anatomist, I now find it impossible to look at the body of my patient without having in my consciousness the structure of what lies beneath my needle.
Working on two levels
If I am treating someone with sciatic pain for example, I am choosing typical points – such as GB 30 huan tiao in the buttock and BL 40 wei zhong at the back of the knee. I know that I can needle GB 30 to remove obstructions from the channel, tonify qi and blood, or resolve damp heat. I also know that I am placing my needle directly over the sciatic nerve.
Traditionally, the point is located at one third distance from the greater trochanter of the femur to the sacral hiatus, with the patient positioned lying on their side (lateral recumbent) with their hip uppermost and the hip rotated inwards (medially). When lying on their front (prone), the point is found closer to the sacral hiatus as the position of the hip – and so the greater trochanter – has changed.
The relationship between the bony landmarks remains the same regardless of the BMI of the patient – however the surface distance may vary according to how fleshy the buttocks are. Knowing that the point lies over the sciatic nerve means that I have additional information to help me find it.
What is not mentioned in point location instructions is that the nerve also passes immediately lateral to the sacrotuberous ligament. When feeling for the point, having made the surface measurements, I can confirm the location by palpating until I find the place where my finger falls off a more rigid structure into the flesh next to it.
When I think about needling BL 40 behind the knee, I also know that this is where the sciatic nerve reappears from beneath the hamstring muscles as they separate to form the soft space at the back of the knee – the popliteal fossa. Needling here will therefore directly affect the main sciatic nerve at another point on its pathway down to the foot.
Decoding ancient reasoning
This example of GB 30, BL 40 and the sciatic nerve is a mishmash of ancient and modern knowledge. In our time, we all know that nerves innervate muscles and carry sensation back to the brain. In addition, we know that arteries carry blood away from the heart, veins bring blood back to the heart, and the heart acts as a pump. However, these pieces of knowledge are very recent.
Blood is at the heart of traditional Chinese medicine. It warms, irrigates and nourishes the human body. From looking at the texts, I would argue that to make sense of what they found in the body, the ancient Chinese physicians turned to their knowledge of how water flows. This was based on their observation of how water moves through the natural landscape, as well as the managed canals and waterways created during the flowering of science and engineering that was the hallmark of the Han era.
Drought and famine were considered signs of heavenly displeasure, with the implication that the emperor had lost the mandate of heaven, and with it the right to rule. The ability to control the flow of water and to create a system of canals which would ensure agricultural security was a masterpiece of Han era engineering. It also had huge political significance, allowing successive Han emperors to maintain their rule by ensuring that fields were irrigated and the crops grew.
When looking at the body therefore, the flow of blood through the different vessels was analogous with the flow of water in the land. Controlling that through the use of acupuncture would ensure the proper flow, and with it the health of the body.
Applying different ways of seeing
Visualising the body as a series of canals with fluid flowing through them at different speeds is a fundamentally different perspective to our modern one. In a system that has tributaries there can be blockages, or places where there is insufficient flow, and places where there is excessive fluid.
Using moxa at ST 36 zu san li and SP 6 san yin jiao is a well-established way of strengthening and moving qi and blood.
ST 36 is located where the neurovascular bundle that travels down the front of the leg and over the dorsum of the foot first emerges near the surface. The main blood and nerve supplies coming down the leg congregate at back of the knee in the popliteal fossa. From the back of the knee, they come through to the front of the leg via the space between the tibia and fibula. ST 36 therefore is the first place in the leg where the blood supply is close enough to the surface to be readily accessible to be warmed with moxa.
SP 6 is anatomically similar in that it lies over the place where the posterior neurovascular bundle comes close to the surface. From the back of the knee, the bundle goes straight down tucked in behind the tibia until it comes to the surface on the inside of the leg at SP6.
Knowing that these anterior and posterior blood vessels are close to the surface and easily accessible at these two points informs the decision to apply moxa there rather than at any other. These are the places where adding warmth will have the most impact on the blood that is flowing directly beneath the moxa.
What it means to me
The ancient Chinese texts refer to the use of anatomical dissection to understand the body, measure and describe it. My research shows that acupuncture meridians are primarily descriptions of the fascial planes where the arteries, nerves and veins run – and the points are highlighting key structures of interest to ancient physicians. This implies that in the Han era, acupuncture started out as ‘cutting edge’ medical science.
Without doubt, marrying ancient and modern anatomical understanding to create a coherent whole – understanding flow through the body, and combining that with some of the modern insights into human anatomy – has brought a greater depth of understanding to my acupuncture practice. Rooting my point choices in the knowledge of what lies inside the body, underneath my needles, is now an integral part of the way I work.
As far as I am aware, there are no concepts in modern science that correspond to the analogy of flow that I see in the Classics. Using the analogies that we find in the Chinese texts gives greater depth to point choices. Empirical evidence is a very powerful truth, and anatomical explanations ancient and modern can be used to inform and support the decisions we make in the clinic.
Vivien Shaw is an anatomist and acupuncturist who combines her two great interests to explore the origins of acupuncture.
All images by Isabelle Winder
