There are three classifications for the internal organs in Chinese medicine. The Zang, or organs, are the solid Yin organs which are characterized by their capacity to store but not drain. They are the Heart, Lungs, Liver, Spleen, Kidneys, and Pericardium. The Fu, or hollow Yang bowels, drain but do not store. They are the Small Intestine, Large Intestine, Stomach, Gall Bladder, Bladder, and Triple Heater. The extraordinary bowels are hollow but also store vital substance. They are the Brain, Marrow, Bones, Blood Vessels, Gall Bladder, and Uterus.
The Zang and Fu are grouped, by elemental association, into five pairs (with an additional pair for the Fire element). The elements of Wood, Fire, Earth, Metal, and Water are respectively associated with the Liver / Gall Bladder, Heart / Small Intestine and Pericardium / Triple Heater, Spleen / Stomach, Lung / Large Intestine, and Kidneys / Bladder. The channels for the Yin organs are located on the ventral (front) aspect of the body, and the Yang bowels on the dorsal (back) aspect. The Zang primarily mediate the internal functions of the organ system, while the Fu are responsible for their manifestation in the world (see The Function of the Gall Bladder in Chinese Medicine). Internal organ dysfunction is expressed through the channels of the bowels, and generally this is felt as pain. For this reason, people primarily complain of symptoms associated with the channels related to the bowels, instead of those related to the organs. This idea bears some relationship to the notion of referred pain in Western medicine. However, the idea is much more prominent in Chinese medicine. This is because of the system of acupuncture channels, which connects the myofascial tissues of the body to the internal organs and bowels.
People typically seek medical attention due to some experience of discomfort. As we are not usually aware of the sensation of an organ itself, it is often through myofascial pain that we know something is wrong. From this perspective, pain (or any other symptom) becomes a signal rather than the core problem. The ZangFu model allows for the correlation of symptoms with specific internal imbalances, and these with specific causes. In Chinese medicine, this becomes the discussion of diet, lifestyle, and emotion (see Causality in Chinese Medicine – The Issues of How and Why).
For example, people complain of tennis elbow, not Heart pain. Sciatica manifests along the Gall Bladder and Bladder channels, but people do not typically complain of Liver or Kidney discomfort. The Liver is responsible for planning in Chinese medicine. It is the Gall Bladder which is responsible for the execution of the plans. Hip pain along the Gall Bladder channel may be representative of a person being stuck and not moving, or not executing their plans. From this perspective, it is possible to attribute personal meaning to one’s symptoms. If this understanding produces transformation in one’s life, this is considered the highest level of healing in Chinese medicine. For a thoughtful discussion on the relationship between the ZangFu, the acupuncture channels, the myofascial tissue, and the interpretation of symptoms, see BodyMind Energetics by Mark Seem.