Twelve meridian sinews is an attaching part of the twelve regular meridians. It is a muscle, tendon, ligaments, mesenterium and some tissues that nourished by the twelve regular meridians. Every meridian sinew is made of many segment meridians. Each segment has its enthesis, which known as starting points, segment, distribution, scatter. Most enthesis is attachment area of muscle and tendons of joint. Some composed muscles of twelve meridian sinews are whole piece of muscle, others are parts of muscle. Because of the distribution range of muscles are different, some muscles are nourished by one meridian and vessels’ Qi and blood.

Once the twelve regular meridians suffer disease, it will influence the running of Qi and blood. The corresponding muscle and tendons which are nourished by meridian and vessels will suffer locomotive system disease. In clinical, the twelve regular meridians will appearance manifestations of disease, it has manifested that no power, spasm, paralysis, atrophy, aching pain, clonus pain even cautery and pain, local pyrexia or degrade local temperature of muscle and joint. According to these manifestations of diseases, it would use acupuncture, massage and medicines to treat disease acupoints of meridian and circulate local area.

The distributing location of twelve meridian sinews on human body, basically according to the circulation line of the twelve regular meridians, it also has some branches belong this meridian range, such as large intestine meridian sinew of hand yangming, whose termination on the outside of nose, while meridian sinew either distributed on the outside of nose or from lower mandible to forehead. The Stomach meridian sinew of Foot-Yangming distributed not only inside of this meridian, but also distributed on the backbone of back. The Urinary Bladder meridian sinew of Foot-Taiyang from back through neck distributed to face. The Gall Bladder musclature of Foot-Shaoyang distributed to sacrum. The Liver meridian sinew of Foot-Jueyin;liver meridian has no whole distribution, just reach perineal position. 

These are beyond to the meridian sinew branch of meridian line distribution. It is show that there are problem would not explained by this meridian distribution line, such as why Hegu and Yangxi can treat headache; Shangliao originate from meridian of Foot-Yang; Foot-SHAO YANG is below interosseous space of lumbar condyles on scattered pulse illustration, all of these arebased on its branches. There are still some distributions left with no theory evidence, such as Foot-SHAO YIN. The meridian line distribute definitely on tongue, bur there are no triple-warmer meridian  of hand shaoyang and the Urinary Bladder Meridian  of Foot-Taiyang distribute on tongue line in the meridian sinews distribution record, while meridian sinews are all distribute on the tongue; The Large Intestine Meridian  of Hand-Yangming has no distribution line from left and right to forehead, there is a meridian which like the Stomach Meridian  of Foot-Yangming distribute on the forehead, while this meridian sinew distribution has no record on The Stomach Meridian sinew of Foot-Yangming.

The distribution rule of twelve meridian sinews: three yang meridians of foot are all distribute on the pars zygomatica of face, while three yin meridians of foot are all end at the perineum; three yang meridians of hand are all distributed on the temples area, while three yin meridians of hand are all end at gastric cavity area below the chest.

In the ancient time, twelve meridian sinews has not been draw. This illustration refers to the first picture of The Jingluo Shijiang, which is published from the people publishing house of Shanghai in 1976 and according to the picture of Neijing. For easy to apply to the clinic, this illustration refers to human anatomy list relevant muscle on the distribution illustration of each meridian sinew, which is according to distribution range record of twelve meridian sinews and the manifestations of disease of each meridian sinew. The Revised edition has added the manifestations of disease content of each meridian sinew.