Divergent Meridians, Collaterals, Meridian Tendon and Skin Areas
I. Divergent Meridians Divergent meridians, the main branches of the regular meridians, branch out from the regular meridians and run along the chest, abdomen and the head. The twelve divergent meridians are distributed in a branching manner from certain parts of the four limbs. This occurs mostly above the elbows and knees of the twelve regular meridians. This is called "departing. " They then enter the deep inside of the viscera, called "entering," and finally travel outward to the exterior of the body this is called "coming out. " The meridians running upward to the face and head, where the yin divergent meridians combine with the yang divergent meridians, is called "combining. " So, the characteristics of the distribution of the twelve divergent meridians can be described by four words, namely "departing," "combining," "coming-out," "entering. " Every of exterior-interiorly related divergent meridians is called a "combination," and there are six combinations altogether. The divergent meridians play a supplementary role. They reinforce connections between meridians and the twelve meridians. The divergent meridians have certain important functions in physiology, pathology, clinical treatment, etc. The main points are as follows : (1) To reinforce the connection of a pair of exterior-interiorly related meridians of the twelve regular meridians in the body. After entering the body, the exterior divergent meridians and the interior divergent meridians run side by side, passing through the exterior-interiorly related viscera; the yin divergent meridians combine with the yang divergent meridians when they run outward to the exterior of the body. Then, they pass into the yang meridians in the exterior of the body together. In this way, they reinforce the connection of the two meridians which are exterior-interiorly related. (2) To reinforce the centripetal connections of the exterior and interior of the body,and of the limbs and the trunk. The twelve divergent meridians play a very importan role in enhancing the relationships between the meridians and collaterals and in passing messages from the exterior to the interior of the body. These meridian branches out from the parts of four limbs of the twelve regular meridians and run centripetally once they enter the inside of the body. (3) To reinforce the connection of the twelve regular meridians and the area of the face and head. The regular meridians which run upwards to the area of the face and head are mainly the six yang meridians of the twelve regular meridians. In the case of the twelve divergent meridians, all the six yang and six yin divergent meridians run upward to the area of the head; the divergent meridians of the three yin meridians of foot run upward to the head after combining with the divergent meridians of the yang meridians. This is the foundation of the theory that "the blood and qi of the twelve regular meridians and the three hundred and sixty-five collaterals, all travel upward to the face and reach the orifices of the body. " (Chapter 4 in the Spirit Pivot). (4) To enlarge the scope of the indications concerning the twelve regular meridians. With the distribution of the twelve divergent meridians over areas that the regular meridians do not cover, the sphere of acupoints of the regular meridians are enlarged. For example, the Taiyang Meridian of Foot does not reach the anus, but its divergent branches pass into the anus. Therefore, the points Chengshan, and Chengjin belonging to the Taiyang Meridian can be used to treat diseases of the anus. (5) To strengthen the relations of the three yin and yang meridians of "the foot with the heart. The three yin and yang divergent meridians run through the abdomen and chest to strengthen the interior-exterior communication of the viscera in the abdomen and the connection with the heart in the chest. Thus, the twelve divergent meridians are very important for the analysis of the relations of the internal organs in the abdomen to the physiological and pathological changes of the heart. At the same time, it also offers the basis for the theory of "the heart as the great monarch of the five zang-viscera and six fu-viscera. " II. Collaterals Collaterals are branches of smaller meridians derived from the regular meridians, and mostly distribute themselves on the surface of the body. There are fifteen collaterals including the twelve collaterals from the twelve regular meridians, and collaterals of Ren,Du meridians, and the major collateral of the spleen. They are also called "the sixteen collaterals" when the major collateral of the stomach is included. The smallest collaterals are called the "minute collaterals. " Chapter 17 in Spirit Pivot described, "The collatera branches are called the small collaterals. " The collaterals which distribute over the surface of the skin are called superficial collaterals. " Chapter 10 in Spirit Pivot said : " The superficial collaterals are commonly seen on the surface of the body. The main physiological functions of the collaterals are as follows: (1) To strengthen the relations of the two interior-exteriorly related meridians on the body surface of the twelve regular meridians. The connections and relations of the two interiorly-exteriorly related meridians within the region of the limbs are established and strengthened by the yin collaterals which run into the yang meridians and the yang collaterals which run into the yin meridians. Although some of the collaterals run into the chest and abdomen, which connect the viscera, they have no fixed connecting objects. (2)To play the governing role and to strengthen the general connection of the anterior, posterior and lateral aspects of the body. The collaterals of the Ren Meridian distribute on the abdominal area, while the Du Meridian runs on the back region, and, the major collateral of the spleen runs on the thoraco-hyperchondriac region; thus, the collaterals strengthen the connection of the anterior, posterior and lateral aspects of the body. (3) To nourish and transport qi and blood to the whole body. The minute and superficial collaterals branching out from the collaterals distribute the qi and blood all over the body, network and connect the tissues of the whole body. Therefore, the qi and blood running in the meridians change their linear flow into a proliferation through the collaterals and minute collaterals. This occurs in order to fully nourish the whole body. III. Meridian Tendons The meridian tendons comprise the system of the twelve regular meridians, which connects tendons and muscles of the body. Its functional activities rely on the nourishing of qi and blood of the meridians and is regulated by the twelve regular meridians. It is also deviated into twelve regions called "The twelve meridian tendons. " The twelve tendons possess physiological functions connect and maintain the bones and the normal movement of the joints. Chapter 44 in Plain Questions says. "The meridian tendons" dominate and control the bones and promote the joints movements. IV. Skin Areas The skin areas are referred to as the regions divided according to the distributions of the meridians and collaterals on the surface of the body. Chapter 56 in Plain Questions states: "The skin can be divided into different regions," and "The skin is the exterior region where the meridians distribute. " The twelve regular meridians and their attached collaterals distribute on certain areas of the body surface, and accordingly, the whole skin of the body is divided into twelve areas which is termed "the twelve skin areas. " Chapter 50 in Plain Questions states. "The skin areas are marked by the regular meridians" and "The skin areas are the parts of meridian system located in the superficial region of the body. " Thus, the skin areas belong to the region where the meridians and collaterals distribute, and the meridian-qi remains. It is helpful to diagnose diseases of the viscera, meridians and collaterals through observing the changes of the color and morphology of the different cutaneous regions. The therapies of external pasting, moxibustion, and hot medicated compressing applied to certain areas of the skin for treatment of internal visceral diseases derive from the application of the skin areas theory on diagnosis and treatment.
