Channel sinews and divergent channels

The Lingshu, the second half of the Yellow Emperor’s Inner Canon, describes the twelve channels in its chapter 10 and then gives each of them three further structures: a connecting vessel (luo mai 絡脈) in the same chapter, a divergent channel (jing bie 經別) in chapter 11 and a channel sinew (jing jin 經筋) in chapter 13. The Suwen adds a fourth, a region of skin (pi bu 皮部) for each channel, in its chapter 56. The WHO International Standard Terminologies on Traditional Medicine in the Western Pacific Region of 2007 defines all four, under the English names meridian divergence, meridian sinew, collateral vessel and cutaneous region. None of the four carries points of its own. This page sets out what each text says, how later practice uses the sinews in particular, and what research has tested. The channel system, counted covers the twelve channels themselves.

The channel sinews

Chapter 13 of the Lingshu, Jingjin, describes twelve sinews, one under the name of each channel, in a fixed form. Each starts at a finger or toe and runs towards the trunk and head, binding (jie 結) at the ankle or wrist, the knee or elbow, the hip or shoulder, and at points on the head and face. The foot taiyang sinew, for instance, starts at the little toe, binds at the ankle, knee and buttock, runs up beside the spine to the nape and binds at the occiput and the nose. No sinew is said to belong to an organ, as every channel in chapter 10 does.

The disorders the chapter lists for each sinew are mostly local: cramp, pain and stiffness along its course, such as a shoulder that will not lift or a neck that cannot turn. A few reach further, such as convulsions under the foot shaoyin sinew. Each disorder is named a bi (痹, an obstruction) of one month of the year, so the foot taiyang disorder is the mid-spring bi. The same treatment closes almost every entry: 治在燔鍼劫刺，以知為數，以痛為輸, treat with the heated needle inserted swiftly, needle as many times as it takes to have an effect, and take the painful place as the point. The chapter ends by sorting the disorders by temperature: cold makes the sinews contract and the back arch, heat makes them slack, and the heated needle is for the cold kind only. For one disorder, a face pulled to one side when the cheek sinew of the foot yangming is affected, the chapter gives a separate remedy: horse fat on the tight side and cinnamon in wine on the slack side.

The WHO terminology keeps both parts of that treatment. It defines red-hot needling (焠刺) as an ancient method of swift pricking with a red-hot needle, and the ouch point, or ashi point, as a point with no name or fixed location, found by tenderness. A 2022 study by Ma, Wang and Zeng traces the courses and disorders of the sinews to two moxibustion texts on eleven vessels excavated at Mawangdui, and argues that attaching the sinews to the twelve channels held back a theory of their own.

Sinews in later practice

Huang, in a 2023 history of needling for sinew disorders, follows the needling methods for sinew disorders from the Lingshu onward and names three concepts that practitioners still argue over: heating with the needle, what chapter 13 means by taking the effect as the count (yi zhi wei shu), and taking the most painful site of a spasm as the point. The paper also sets the sinew techniques against dry needling and asks how the two differ.

Taking the painful place as the point overlaps with needling the myofascial trigger point, which the WHO terminology defines as a sensitive area that produces a reaction elsewhere in the body when stimulated. Dry needling reports the dispute over how far trigger points and acupuncture points coincide, and the reviews of trigger-point needling. Liu, Li and Bian, in a 2026 narrative review of sinew therapy and dry needling for chronic neck pain, frame the correspondences between the sinews and the fascial continuum as clinical heuristics and analogies, not anatomical equivalences or proven mechanisms. An anatomical study by Langevin and Yandow in 2002 concerns the channels and their points rather than the sinews: in serial sections of a human arm it found 80% of acupuncture points sitting on a connective tissue plane between or within muscles.

The divergent channels

Chapter 11 of the Lingshu, Jingbie, asks where the twelve channels separate and rejoin, leave and enter. Its answer is a branch, which it calls the zheng (正, the main or proper course), that leaves each channel on the limb, runs inside the body to the organs and comes out at the neck or face. The branches travel in yin and yang pairs, and the chapter counts six confluences (liu he 六合). The first is the foot taiyang and foot shaoyin, the bladder and kidney channels: the taiyang branch separates at the back of the knee, belongs to the bladder, spreads to the kidney, follows the spine and emerges at the nape to rejoin the taiyang; the shaoyin branch joins it at the knee, rises to the kidney and also emerges at the nape to merge with the taiyang. In each pair the yin branch ends in the yang channel. The chapter names no points.

Two textual studies read chapter 11 as older than the system it sits in. Zhao, in 2008, concluded that the divergences are remains of an eleven-vessel model of the channels and belong to the stage before chapter 10, and that modern accounts confuse their relation to the twelve channels. Gao and colleagues, in 2020, reached a similar view, that the divergences are a remnant of the vessels of the bamboo and silk manuscripts, and located the point where each pair joins in the neck.

Little research has tested them. A 2003 pilot trial by Johnstone and colleagues randomised 30 men with urinary symptoms and a negative prostate biopsy to observation, to nine sessions at points of what the authors call the kidney-bladder distinct meridian, or to nine sessions at points not expected to affect the prostate. Over three months none of the three groups changed significantly in symptom score or prostate-specific antigen, and the authors concluded that needling the kidney-bladder distinct meridian did neither. The abstract does not give the classical source of that pathway, though the Lingshu’s first confluence joins the same two channels.

The connecting vessels and the skin regions

Chapter 10 gives each of the twelve channels a connecting vessel that leaves it at one point and runs to its paired channel, the lung’s at LU07 (Lieque), and adds three more for fifteen, among them the great connecting vessel of the spleen at SP21 (Dabao). Source, connecting and cleft points lists all fifteen and the signs the chapter gives for each. The WHO terminology also names their smaller branches: tertiary or grandchild collaterals (孫絡) and superficial collaterals (浮絡) in the surface layers.

Chapter 56 of the Suwen, Pibu lun, divides the skin into regions by channel and ties them to those surface vessels: the connecting vessels of the twelve channels, it says, are the regions of the skin. It reads the colour of the visible vessels in each region, more blue-green for pain, black for bi, yellow and red for heat and white for cold, and describes disease as entering through the skin, passing to the connecting vessels, then to the channel and then to the organs. Song and colleagues, in 2019, set out the history of the needle tools used on the cutaneous regions, from pressing and pricking tools such as the plum-blossom and three-edged needles to intradermal needles left under the skin.

What trials of sinew therapy report

A 2024 meta-analysis by Kang and colleagues pooled 19 randomised trials, 1,436 patients, of sinew acupuncture for peripheral facial palsy, and found a higher overall response rate than conventional therapy (odds ratio 3.93). The authors write that the small number of high-quality trials limits how far the result can be relied on. Bell’s palsy reports the reviews of acupuncture for that condition.

A 2025 trial by Gong and colleagues randomised 160 people with chronic neck pain and limited extension to six sessions of sinew therapy, applied by hand at sites away from the neck, or of general manual therapy. Extension improved by 22 degrees with sinew therapy and 24 with manual therapy, and the difference between the groups was not significant. Neither the meta-analysis nor the trial compared sinew therapy with a sham.

What the sources cannot tell you

The four pathways are statements of a classical system, and the texts report no outcomes. The textual studies above disagree with the modern picture of a single integrated network: they read the sinews and the divergences as remnants of earlier models that were attached to the twelve channels later. The two trial reports above test treatments named after the sinews, one by needle and one by hand, against other active treatments, so neither result can be credited to the sinew idea rather than to the technique used. AcuiQ codes named points only, so a protocol that needled tender sites along a sinew reaches the index only for the named points its paper lists.