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The Theory of Channels and Collaterals

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Lori Anne
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« on: October 05, 2009, 01:10:42 pm »

The Theory of Channels and Collaterals

The theory of channels and collaterals is an important component of the theoretical system in traditional Chinese medicine. It covers the physiological functions and pathological changes of the channels and collaterals, their interrelations with the zang-fu organs, and is essential in guiding clinical practice, especially acupuncture treatment.
The Formation and Functions of Channels and Collaterals

1. Channels and Collaterals System

The system of channels and collaterals constitutes the twelve regular channels, the eight extra channels, the fifteen collaterals, the twelve divergent channels, the musculo-tendinous and cutaneous regions of the twelve regular channels.

2. Channels and Collaterals Functions

(1) Physiologically, the channels and collaterals are considered to be a series of connecting passages through which qi and blood circulate to regulate the functions of the zang-fu organs, tissues, and sense organs. These passages also conduct the sensations and reactions (deqi) of acupuncture treatment.

The five zang and six fu organs, four limbs, nine orifices, skin muscles, vessels, and tendons, although having their respective physiological functions, also maintain the harmonization and uniqueness of interior, exterior, upper, and lower parts of the body as a united and organic entity. This interconnection and organic combination relies upon the function of the channels and collaterals system.

All the tissues and organs of the human body need the nourishment of qi and blood in order to keep their normal physiological activities. The distribution and circulation of qi and blood throughout the body to nourish the zang-fu, tissues, and organs and to resist exogenous pathological factors depends on the transportation and conduction of the channels and collaterals. As the Lingshu records:

The channels and collaterals are the passages through which blood and qi flow to nourish yin and yang, to moisten tendons and bones, and to lubricate the joints.

(2) Pathologically, channels and collaterals are the pathways through which the exogenous pathological factors are transmitted and their channels reflected. In the Suwen it is noted:

When pathogenic factors invade the skin and the pores are open they enter the collaterals. When the collaterals become full, the pathogenic factors will move into the channels. When the channels are full, the pathogenic factors transmit to and reside in the zang and fu organs.

The interior and exterior, upper and lower parts of the body form an integrated entity through the connecting network of channels and collaterals. So under pathological conditions every part of the body will affect the rest via the channels and collaterals. The channels and collaterals are not only the passages of disease transmission, but can also reflect pathological changes. Namely, the diseases of the zang-fu organs can be reflected on the body surface, especially in certain areas or at certain points, through the transmission of channels and collaterals.

(3) In diagnosis, channels and collaterals have certain running courses that connect with the zang-fu organs. They also reflect pathological changes on the body surface. Therefore clinical diagnosis can be made according to symptoms that are related to those courses and their respective zang-fu organs.

(4) In treatment, the theory of channels and collaterals is extensively used in clinical treatment for different branches of traditional Chinese medicine. Treatments using traditional medicinal herbs are based on their main actions vis-a-vis related zang-fu organs and channels. In the practice of acupuncture, the theory of channels and collaterals is the basis of all treatment and clinical practice. Point selection and prescription combinations are all made on this basis. By stimulating a certain point or area on the body surface the physiological functions of the channels and collaterals are aroused. This action is achieved by propagating sensation through the channels. Without this sensation it is hard to achieve a therapeutic effect.


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« Reply #1 on: October 05, 2009, 01:19:37 pm »

The Twelve Regular Channels

The twelve regular channels are a general term for the three yin and three yang channels of the hand and the three yin and three yang channels of the foot.
1. The Lung Channel of the Hand-Taiyin

Flow sequence : Zhongfu  Chize  Kongzui  Lieque  Jingqu  Taiyuan  Yuji  Shaosh-ang

The lung channel of the Hand Taiyin originates from the middle jiao and descends to connect with the large intestine (1). It turns around the upper orifice of the stomach (2), passing through the diaphragm (3) and enters the lung, forming part of the lung channels system (4) From the lung it flows upward to connect with the throat (5) and exits transversely from the arm pit (6). It then travels along the anterior-medial aspect of the upper arm (7), passing the cubital region and arrives at the Cunkou (Cool, the radial side of the wrist containing the radial artery for pulse palpation. Passing the thenar eminence (9), it travels along the radial border of the palm ending at the medial side of the tip of the thumb, Shaoshang (10). The branch separates from the Lieque (11) near to the wrist and goes directly to the radial side of the tip of the index finger, Shan-gyang (12) where it joins with the large intestine channels of the Hand-Yangming.

Main pathological changes: Cough, asthma, hemoptysis, sore throat, pain and fullness of the chest, pain in the clavicular region, pain along the anterior-medial aspect of the arm, and shoulder pain.

2. The Large Intestine Channel of the Hang-Yangming

Flow sequence : Shang-yang  Erjian  Sanjian  Hegu  Yangxi  Pianli  Wenliu  Shou-sanli  Quchi  Binao  Jianyu  Futu  Ying-xiang

The large intestine channel of the Hang-Yangming starts from the tip of the index finger, Shangyang (1). Running upward along the radical aspect of the index finger, it passes through the inter-space of the first and second metacarpal bones, and ascends along the lateral anterior aspect of the upper arm to the highest point of the shoulder (2). It then travels along the anterior border of the acromion up to the seventh cervical vertebrae (3), then descends to the supraclavicular fossa (4) and enters the thoracic cavity to connect with the lung (5). It passes through the diaphram (6) and enters the large intestine (7), forming part of the large intestine channel system.

The branch from the supraclavicular fossa travels upward to the neck (Cool and to the cheek (9), and enters the lower teeth (10), then it curves around the upper lip and exits at the corner of the mouth (11), where it crosses the opposite large intestine channel of the Hand-Yangming at the philtrum (12). it ends at the side of the nose, Yingxiang (13) where is connects with the stomach channel of the Foot-Yangming.

Main pathological changes: lower toothache, sore throat, epistaxis, runny nose, dryness of the mouth, swelling and pain of the neck, pain or motor impairment of the anterior-lateral aspect of the arm, etc.

3. The Stomach Channel of the Foot-Yangming

Flow sequence : Chengqi  Sibai  Dicang  Jiache  Xiaguan  Touwei  Renying  Quepen  Rugen  Liangmen  Tianshu  Shuidao  Guilai  Qichong  Futu  Liangqiu  Dubi  Zusanli  Shang-juxu  Tiaokou  Xiajuxu  Feng-long  Jiexi  Chang-yang  Xiangu  Neiting  Lidui

The stomach channel of the Foot-Yangming starts from the lateral side of the nose, Yingxiang (1). It flows upward to the bridge of the nose where it meets the urinary bladder channel of the Foot-Taiyang, Jingming (2). Turning downward along the lateral side of the nose, it enters the upper gum (3). Curving around the lips (4), it meets Chengjiang, Ren, at the mentolabial groove (5). Then it travels to the posterior aspect of the mandible passing through the Daying (6) ascending in front of the ear and following the anterior hairline (7), it reaches the forehead (Cool.

The facial branch deviates from the anterior aspect of the Daying and runs downward to the Renying (9). It runs along the throat and enters the supraclavicular fossa (10). Going downward it passes through the diaphragm, enters the stomach (11), forming part of the stomach system, and connects with the spleen (12).

The straight line of the channels separates the supraclavicular fossa and runs downward along the middle mammillary line (13). It travels to the side of the umbilicus (14) and descends to the inguinal groove, where it enters Pt. Qichong (15).

The branch bifurcating from the lower orifice of the stomach (16) descends to the deep layer of the abdomen and joins the previous straight line of the channel at Pt. Qichong (15). Running downward it travels along the anterior aspect of the thigh and reaches the knee (17). From there is continues further down along the anterior border of the lateral aspect of the tibia to the dorsum of the foot and reaches the lateral side of the tip of the second toe, Lidui (18). Another branch splits from Pt. Zusanli (19), and descends downward to enter the lateral side of the middle toe (20).

The branch from the dorsum of the foot parts from Chongyang (21) and flows anteriorly to the medial side of the tip of the great toe, Yinbai (22), where it communicates with the spleen channel of the Foot-Taiyin.

Main pathological changes: borborygmus, abdominal distention, edema, stomach ache, vomiting, diabetes, deviated mouth and eyes, sore throat, epistaxis, high fever, perspiration, headache, mania, and pain along the course of the stomach channel.

4. The Spleen Channel of the Foot-Taiyin

Flow sequence : Yinbai  Dadu  Taibai  Gongsun  Shangqiu  Sanyin-jiao  Lougu  Diji  Yinling-quon  Xuehai  Chongmen  Daheng  Dabao

The spleen of the Foot-Taiyin starts from the medial aspect of the tip of the big toe, Yinbai (1). It travels along the medial aspect of the foot at the junction between the red and white skin, ascends anteriorly to the medial malleolus (2) up to the medial aspect of the leg (3). It crosses and goes in front of the liver channel of the foot-Jueyin 8 cun above the medial malleolus. passing through the anterior medial aspect of the thigh (4), it enters the abdomen (5) and the spleen (6), forming part of the spleen system, and connects with the stomach. From there it traverses the diaphragm (7), and runs alongside the esophagus. It arrives at the root of the tongue (Cool and spreads over the lower surface of the tongue.

The branch goes from the stomach up through the diaphragm and flows into the heart (9) to join the heart channel of the Hand-Shaoyin.

Main pathological changes: epigastric pain, abdominal distension, vomiting after eating food, belching, loose stools, jaundice, lassitude, heaviness of limbs, stiffness of the tongue, coldness, swelling and pain of the lateral side of the lower limb, motor impairment of the big toe, etc.

5. The Heart Channel of the Hand-Shaoyin

Flow sequence : Jiquan  Shaohai  Lingdao  Tongli  Yinxi  Shenmen  Shaofu  Shao-chong

The heart channel of the Hand-Shaoyin commences at the heart (1) and pertains to the "heart system." It descends to pass through the diaphragm (2) and connects with the small intestine (3).

The ascending branch splits from the "heart system" up to the lung (4). Then it turns downward to the axilla, Jiquan (5). From there is goes along the posterior border of the medial aspect of the upper arm (6). Passing through the cubital region (9), it descends to the pisiform region proximal to the palm and enters the palm (Cool. Then it ends at the medial aspect of the tip of the little finger and links with the small intestine channel of the Hand-Taiyang. The branch splits from the "heart system" alongside the esophagus (9) to connect with the "eye system" (10).

Main pathological changes: Pain in the heart region, chest pains, sweating, heart palpitation, insomnia, dry throat, thirst, inner side arm pain, cold extremities, hot palms.

6. The Small Intestine Channel of the Hand-Taiyang

Flow sequence : Shaoze  Qiangu  Houxi  Wangu  Yanggu  Yanglao  Zhizheng  Xiaohai  Jianzhen  Naoshu  Tianzong  Tian-chuang  Quanliao  Tinggong

The small intestine channel of the Hand-Taiyang starts from the ulnar aspect of the tip of the little finger, Shaoze (1) and travels along the ulnar border of the hand dorsum upward to the posterior border of the lateral aspect of the upper arm (2). It passes through the cubital region curving around the scapular region (3) where it meets the Du channel at Pt. Dazhui of Du (4). Then turning downward to the supraclavicular fossa (5), it connects with the heart (6). Alongside the esophagus, it passes through the diaphragm (7), reaches the stomach (Cool and enters the small intestine (9) forming part of its channel system.

The branch separates from the supraclavicular fossa and ascends to the neck (10) and further up to the cheek (11). Going through the outer canthus, it turns into the ear, Tinggong (12).

Another branch deviates from the cheek. Running upward to the lower border of the infraorbital region, it reaches the inner canthus Pt. Jingming (13) to communicate with the urinary bladder channel of the Foot-Taiyang.

Main pathological changes: Ringing in the ears, yellowish eye coloring, sore throat, swelling and pain under the jaw and in the neck, shoulder and upper external arm pain, abdominal pain and distension, frequent urination, etc.

7. The Urinary Bladder Channel of the Foot-Taiyang

Flow sequence : Jingming  Zanzhu  Tianzhu  Dazhu  Fengmen  Feishu  Jueyin  Xinshu  Dushu  Geshu  Ganshu  Danshu  Pishu  Weishu  Sanjiao-shu  Shenshu  Dachang-shu  Xiaoch-angshu  Panggu-angshu  Baihuan-shu  Ciliao  Chengfu  Yinmen  Weiyang  Weizhang  Gaohu-angshu  Zhibian  Cheng-shan  Feiyang  Fuyang  Kunlun  Pucan  Shenmai  Jinmen  Jinggu  Shugu  Zhutong-gu  Zhiyin

The urinary bladder channel of the Foot-Taiyang originates from the inner canthus, Jingming (1). Passing through the forehead, it flows up to the vertex and meets the du channel at Pt. Baihui of Du (2).

A branch splits from the vertex and goes bilaterally down to the upper corner of the ear (3). The straight line enters and connects with the brain from the vertex. It exits the brain at the neck region (4) and bifurcates into two lines. One line runs straight downward (1.5 cun lateral to the mid-line of the back) to the lumbar region (5), entering the body cavity to connect with the kidney and join with the urinary bladder (6), forming a part of its channel system. From there it descends along the posterior aspect of the thigh and ends in the popliteal fossa (7). Another line from the posterior aspect of the neck runs downward along the medial border of the scapula (3 cun lateral to the back mid-line) (Cool. Passing through the gluteal region (9), it meets the proceeding branch descending from the next region to the lumbar region in the popliteal fossa (10). From there it descends to the posterior aspect of the gastrocnemius muscle (11) and further to the lateral posterior side of the tip of the little toe, Zhiyin (12), where it communicates with the kidney channel of the Foot-Shaoyin.

Main pathological changes: dysuria, enuresis, mania or depression, malaria, eye pains, lacrymation on exposure to the wind, nasal obstruction, runny nose, epistaxis, headache, stiffness of the neck, pain of the lower back and hip region and along the course of this channel on the posterior side of the leg.

8. The Kidney Channel of the Foot-Shaoyin

Flow sequence : yongquan  Rangu  Taixi  Dazhong  Shuiquan  Zhaohai  Fuliu  Jiaoxin  Zhubin  Yingu  Henggu  Dahe  Shufu

The kidney channel of the Foot-Shaoyin starts from the interior aspect of the little toe (1), and runs obliquely towards the sole, Yongquan (2). Emerging from the lower aspect of the tuberosity of the navicular bone (3), it travels behind the medial malleolus and enters the heel (4). Ascending along the medial side of the leg (5), it passes the medial side of the popliteal fossa and goes further upward along the posterior-medial aspect of the thigh (6). Penetrating through the vertebral column of the lumbar region, it enters the kidney (7), forming part of its channel system, and links with the urinary bladder (Cool.

The straight line of the channel comes out from the kidney. It ascends passing through the liver (9) and diaphragm (10), enters the lung (11), and runs alongside the throat (12), ending at the root of the tongue.

A branch springs from the lung, links with the heart (13), and flows into the chest to communicate with the pericardium channel of the Hand-Jueyin.

Main pathological changes: shortness of breath, dyspnea, cough, hemoptysis, dizziness, vertigo, dryness of the tongue, sore throat, low back pain, frequent urination, enuresis, spermatorrhea, impotence, dysuria, constipation or diarrhea, irregular menstruation, pain of the lumbar spine or along the posterior-medial side of the thigh, weakness of the lower limbs, feverish sensation of palms and soles, etc.

9. The Pericardium Channel of the Hand-Jueyin

Flow sequence : Tianch  Quze  Ximen  Jianshi  Neiguan  Daling  Laogong  Zhong-chang

The pericardium channel of the Hand-Jueyin originates in the chest (1). It enters the pericardium, then descends to pass through the diaphragm (2). Running through the abdomen, it connects successively with the upper, middle, and lower jiao.

A branch springs from the chest (1) and emerges from the costal region to a point 3 cun below the anterior axillary fold, Tianchi (3). It then ascends to the axillary fossa and along the medial aspect of the upper arm (4), it runs downward between the lung channel of the Hand-Taiyin and the heart channel of the Hand-Shaoyin (5). After emerging in the cubital fossa, it goes further downward to the forearm between the tendons of the m. palmaris longus and m. flexor carpi radialis (6). It enters the palm (7) and passes along the middle finger to its tip, Zhongchong (Cool.

Another branch splits from the palm at Pt. Laogong (P. Cool (9), runs along the ring finger to its tip, Quanchong (10) and communicates with the sanjiao channel of the Hand-Shaoyang.

Main pathological changes: palpitation, irritability, pain in the precardiac region, stuffy chest, mental disorder, swelling and pain of the axillary region, spasm or contracture of the elbow, feverish sensation in the palm, etc.

10. The Sanjiao Channel of the Hand-Shaoyang

Flow sequence : Guanchong  Yemen  Zhongzhu  Yangch  Waiguan  Zhigou  Huizong  Sangany  Jianliao  Yifeng  Jiaosun  Ermen  Sizhukong

The sanjiao channel of the Hand-Shaoyang originates from the tip of the ring finger, Guanchong (1). It travels upward between the fourth and fifth metacarpal bones and along the dorsal side of the wrist and the lateral side of the forearm between the radius and ulna, it passes through the olecranon (2). Then it runs along the lateral aspect of the upper arm and reaches the shoulder region (3) where it travels across and behind the gall bladder channel of the Foot-Shaoyang. Crossing over the shoulder, it enters the supraclavicular fossa (4) and spreads in the chest to connect with the pericardium (5). It then proceeds through the diaphragm (6) down the abdomen, and communicates with the upper, middle, and lower jiao forming a part of the sanjiao channel system.

A branch springs from the chest (7) and runs upward exiting from the supraclavicular fossa, and ascends to the neck (Cool. Running along the posterior border of the ear (9), it crosses from the superior aspect of the ear to the corner of the forehead (10). Then it turns downward to the cheek and terminates in the infraorbital region (11).

Another branch arises from the anterior aspect of the ear 912). It crosses the former branch at the cheek and reaches the outer canthus (13) to link with the gall bladder channel of the Foot-Shaoyang.

Main pathological changes: deafness, ringing in the ears, sore throat, pain of the outer canthus, swelling of the cheek, pain of the retroauricular region, shoulder and lateral aspects to the upper arm and elbow, dysuria, edema, enuresis, abdominal distension, etc.

11. The Gall Bladder Channel of the Foot-Shaoyang

Flow sequence : Tongzi-liao  Tinghui  Yangbai  Fengchi  Riyue  Jingmen  Daimai  Juliao  Huantiao  Fengshi  Yangl-ingquan  Yangjiao  Waiqiu  Guang-ming  Yangfu  Xuanzhong  Qiuxu  Zulinqi  Xiaxi  Zuqiao-yin

The gall bladder channel of the Foot-Shaoyang starts from the outer canthus, Tongziliao (1) and ascends to the corner of the forehead, Hanyan (2) and then winds downward to the retroauricular region, Fengchi (3). It then runs along the lateral side of the neck emerging in front of the sanjiao channel of the Hand-Shaoyang (4). It traverses behind the sanjiao channel of the Hand-Shaoyang at the shoulder region and travels further down to the supraclavicular fossa (5).

The retroauricular branch passes through the ear (6) and emerges in front of the ear at the posterior side of the out canthus (7). A branch comes out from the outer canthus (Cool, runs downward to the Daying (9) and meets the sanjiao channel of the Hand-Shaoyang at the infraorbital region 910). Descending and passing through the Jiach (11), it reaches to the neck and enters the supraorbital fossa to meet with the main line of the channel (12). From there it further descends and enters the chest (13), passes through the diaphragm to connect with the liver (14) and enters the gall bladder (15), forming part of its channel system. It then travels interiorly in the hypochondriac region, emerging at the lateral side of the lower abdomen near the femoral artery in the inguinal region (16). Then it curves along the margin of the public hair and runs transversely into the hip region, Huantiao (17).

The straight line of the channel travels downward from the supraclavicular fossa (18), and further down to the axillary region (19). Along the lateral side of the chest (20) and through the free ends of the floating ribs (21), it meets the former branch at the hip region (22). It then travels downward along the lateral side of thigh to the lateral side of the knee (23). Further descending along the anterior aspect of the fibula (24), it reaches the lower end of the fibula, and the anterior aspect of the lateral malleolus (25). Following the dorsum of the foot, it terminates at the lateral side of the fourth toe's tip, Foot-Qiaoyin (26).

The branch splitting from Foot-Linqi (27) runs between the 1st and 2nd metatarsal bones to the hairy area of the big toe, Dadun (28) where it communicates with the Liver channel of the Foot-Jueyin.

Main pathological changes: alternate chills and fever, bitter taste in the mouth, blurred vision, vertigo, hypochondriac pain, migraine, pain in the supraclavicular fossa, pain of the outer canthus and axillary fossa, malaria, pain along the lateral side of the thigh, knee and leg, pain and motor impairment of the fourth toe, etc.

12. The Liver Channel of the Foot-Jueyin

Flow sequence : Dadun  Xingjian  Taichong  Zhong-feng  Ligou  Zhongdu  Ququan  Zhongmen  Qimen

The liver channel of the Foot-Jueyin originates from the dorsal hairy region of the big toe, Dadun (1). Ascending along the dorsum of the foot, it flows further upward to the anterior aspect of the medial malleolus (2) where is crosses behind the spleen channel of the Foot-Taiyin to the area 8 cun above the medial malleolus (3). Then it runs upward to the medial side of the knee (4) and along the medial aspect of the thigh (5) into the pubic hair region (6). From there it curves around the external genitalia and travels up to the lower abdomen (7). Alongside the stomach, it enters the liver (6), forming part of its channel system, and connects with the gall bladder (9). Then it proceeds upward to pass through the diaphram (10) and disperses in the costal and hypochondriac region (11). Ascending along the posterior aspect of the throat (12), it emerges in the nasopharynx region (12) to connect with the "eye system" (13). Extending further upward, it exits from the forehead (14) and meets the Du channel at the vertex (15).

A branch arising from the "eye system" descends to the cheek (16) and curves around the internal surface of the lips (17). another branch separating from the liver (18), passes through the diaphragm and enters the lung (19) to link with the lung channel of the Hand-Taiyin.

Main pathological changes: pain and distension of the hypochondrium, stuffiness of the chest, vomiting, diarrhea, vertex headache, hernia, dysuria enuresis, pain and distension of the lateral lower abdomen, lumbago, irregular menstruation, mental disorders, etc.

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« Reply #2 on: October 05, 2009, 01:29:06 pm »

1. Pathways and Conjunctures

The running direction and the interconjunction of the twelve regular channels compose the following network : the three yin channels of the hand run from the chest to the hand, connecting with the three yang channels of the hand; the three yang channels of the hand run from the hand to the head, joining with the three yang channels of the foot; the three yang channels of the foot travel from the head to the foot, uniting the three yin channels of the foot; the three yin channels of the foot proceed from the foot up to the abdomen, linking with the three yin channels of the hand.

2. Exterior-Interior relationships and the Order of the Qi Flow in the Channels

The twelve regular channels of the hand yin-yang and foot yin-yang respectively have a connecting relationship with their pertaining zang or fu organ. Specifically, yin channels pertain to zang organs and connect with fu organs, while yang channels pertain to fu organs and connect with zang organs. The exterior-interior relationship of the twelve regular channels is the same as the exterior-interior relationship of the yang and fu organs.

Channels which have an exterior-interior relationship run opposite each other on the lateral and medial aspects of the four limbs (except the liver channel of the Foot-Jueyin and the spleen channel of the Foot-Taiyin which change their position 8 cun above the medial malleolus of the lower limbs). These channels then connect with each other on the hand or foot, forming the six pairs of exteriorly-interiorly related channels of the zang-fu organs. Qi flows continually, circulating throughout the channels in the human body.

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