Twelve channel divergences

Branches of each of the twelve channels that reach deeper parts of the body and then return to the primary channel. The divergences of the six yáng channels return to the yáng channel they branched from. The yīn channel divergences connect to the channel with which they stand in exterior-interior relationship. For this reason, the twelve channel divergences have the function of complementing the main pathways by providing a link between the yīn and the yáng channels.

The pathways of the channel divergences of the yīn and yáng channels differ. The yáng channel divergences enter the chest or abdomen to connect with the bowels and viscera they home to and net, going on to surface at head and nape. They unite with (合于 hé yú), i.e., rejoin, the yáng channel they belong to. The places where they unite with the primary channel are called are the six unions (六合 liù hé). The yīn channel divergences unite with the exterior-interior paired yáng channel but do not rejoin their home channel. Hence, there only six unions, not twelve.

The importance of the channel divergences is primarily theoretical. Their pathways are used to explain the functions of various acupuncture points and the connection between various organs and parts of the body. For example, points on yīn channels that affect the head are said to do so, in part, because the yīn channel divergences all connect with yáng channel divergences, which then rise to the head. Another example is that of the channel divergence of the bladder channel that diverges from the main channel at the back of the leg and proceeds upward to the anus and thus explains the function of several bladder points on the lower leg with regard to treating hemorrhoids, and other disorders of the anal region.

Foot Greater yáng (tài yáng)—Foot Lesser yīn (shào yīn) (Union 1)

Foot greater yáng (tài yáng) bladder channel divergence: This divergence leaves the primary channel at the popliteal fossa and ascends the leg. From a point 5 cùn below the coccyx, one pathway enters the anal region, homes to the bladder, disperses over that organ and then follows the spine upward to the neck where it homes to the primary channel. From the same point, the main pathway continues upward either side of the spinal column to issue at the nape and unite with its primary channel, the foot greater yáng (tài yáng) bladder channel.

Foot lesser yīn (shào yīn) kidney channel divergence: This divergence leaves the primary channel at the popliteal fossa and unites with the foot greater yáng (tài yáng) bladder channel divergence. It rises to the kidney and at the second lumbar vertebrae it homes to the girdling vessel. It then rises to connect to the root of the tongue and issues at the nape, where it unites with the foot greater yáng (tài yáng) bladder channel divergence.

Foot Lesser yáng (shào yáng)—Foot Reverting yīn (jué yīn) (Union 2)

Foot lesser yáng (shào yáng) gallbladder channel divergence: This divergence leaves the primary channel at the lateral aspect of the thigh, passes to the anterior aspect of the thigh, and enters the pelvic region at the border of the pubic hair, where it unites with the foot reverting yīn (jué yīn) liver channel divergence. Here it enters the area of the free ribs, homes to the gallbladder and disperses over the liver. Rising upward, the divergence links with the heart, ascends the esophagus, issues at the submandibular region, and disperses over the face and eye connector region (behind the eye) to finally unite with its primary channel, the foot lesser yáng (shào yáng) gallbladder channel at the outer canthus.

Foot reverting yīn (jué yīn) liver channel divergence: This divergence leaves the primary channel at the dorsal aspect of the foot and rises along the border of the pubic hair region, where it unites with and follows the foot lesser yáng (shào yáng) gallbladder channel.

Foot yáng brightness (yáng míng)—Foot Greater yīn (tài yīn) (Union 3)

Foot yáng brightness (yáng míng) stomach channel divergence: This channel divergence leaves the primary channel at the anterior thigh and enters the abdominal cavity, where it homes to the stomach and disperses over the spleen. It rises passing the heart and following the esophagus to issue at the mouth. It then continues upward past the root of the nose to the suborbital region to link with the eye connector (region behind the eye) and unite with the primary channel, the foot yáng brightness (yáng míng) stomach channel.

Foot greater yīn (tài yīn) spleen channel divergence: The divergence leaves the primary channel at the inside of the thigh and ascends to the hip where it unites with the foot yáng brightness (yáng míng) stomach channel divergence. It then rises and binds at the pharynx and links with the root of the tongue.

Hand Greater yáng (tài yáng)—Hand Lesser yīn (shào yīn) (Union 4)

Hand greater yáng (tài yáng) small intestine channel divergence: The divergence separates from the primary channel at the shoulder, enters at the axilla, goes to the heart and proceeds downward to connect to the small intestine.

Hand lesser yīn (shào yīn) heart channel divergence: This divergence leaves the primary channel at the axillary fossa (at GB-22, yuān yè) and enters the chest and homes to the heart. It then runs up the throat emerging at the face and uniting with the hand greater yáng (tài yáng) small intestine channel at the inner canthus.

Hand Lesser yáng (shào yáng)—Hand Reverting yīn (jué yīn) (Union 5)

Hand lesser yáng (shào yáng) triple burner channel divergence: This divergence leaves the primary channel at the vertex. From there it descends through the supraclavicular fossa and then through each of the three burners, dispersing in the chest and abdomen.

Hand reverting yīn (jué yīn) pericardium channel divergence: This divergence leaves the primary channel three cùn below the axilla and extends into the chest where it homes to each of the three burners. It then rises along the throat and issues behind the ear to unite with the hand lesser yáng (shào yáng) triple burner channel (below the bone behind the ear).

Hand yáng brightness (yáng míng)—Hand Greater yīn (tài yīn) (Union 6)

Hand yáng brightness (yáng míng) large intestine channel divergence: After leaving the primary channel at the shoulder near LI-15 (jiān yú), this divergence enters the spine at the nape (at the 7th cervical vertebra) and descends through the supraclavicular fossa to the large intestine. At the same time, it homes to the lung from where it rises along the throat and surfaces again at the supraclavicular fossa to rejoin its primary channel, the hand yáng brightness (yáng míng) channel.

Hand greater yīn (tài yīn) lung channel divergence: After departing from the primary channel, the divergence enters the region below the axilla near GB-22 (yuān yè) and from there travels in front of the channel divergence of the heart, enters the lung and proceeds downward to disperse over the large intestine. A branch also rises up to the supraclavicular fossa and follows the throat upward to u with the hand yáng brightness (yáng míng) large intestine channel divergence.

The channel divergences, like the network vessels described below, serve to connect the yīn-yáng organ pairs, but they differ in important ways. The channel divergences are not associated with specific symptoms as the network vessels are. The departure of the channel divergence from the home channel is not marked by a specific acupoint, as the network vessels are. The channel divergences traverse the interior of the body, while the network vessels relate to the exterior of the body.

The importance of the channel divergences is primarily theoretical. Their pathways are used to explain the function of various acupuncture points and the connection between various organs and body parts. For example, points on the yīn channels that affect the head are said to do so, in part, because the yīn channel divergences unite with the yáng channels that rise to the head. Another example is that of the channel divergence of the bladder channel that separates from the main channel at the back of the leg and proceeds upward to the anus, thus explaining the function of several bladder point on the lower leg with regard to the treatment of hemorrhoids and other conditions of the anus.