阳主四肢。经曰∶四肢者，诸阳之本也。又曰∶结阳者肿四肢。又曰∶四肢禀气于胃，而不得至经，必因于脾，乃
得禀也。脾虚则四肢不用。又曰，四肢懈惰，此脾精之不行也。
肝主筋，而各经俱有，大抵随其脉之所在而连属也。详具《灵枢·经筋》篇。
肾主骨，在体为骨，在赃为肾。又曰∶肾之合，骨也；其荣，发也。又曰∶少阴者冬脉也，伏行而温于骨髓。骨病
忌食苦甘，久立。经曰∶多食甘，则骨痛而发落。又曰∶苦走骨。骨病无多食苦。又曰∶久立伤骨，骨病不屈。
经曰∶手屈而不能伸者，病在筋；伸而不能屈者，病在骨。
脾主肉。经曰∶脾主肉，在体为肉，在脏为脾。又曰∶邪在脾胃，则肌肉痛是也。肉之小为会为溪（谓肉少处
也），肉之大会为谷（即多肉处也），分肉之间、溪谷之会，以行荣卫，以会大气。湿伤肉，甘伤肉。又曰∶甘走肉。肉
病无多食甘。久坐伤肉。
皮肤属肺。经曰∶肺之合皮也，其荣毛也。毛折爪枯，为肺绝。经曰∶太阴者，行气温于皮毛者也。气不荣则毛
焦，皮毛焦则津液去，津液既去，则爪枯毛折，皮肤痛，属心实。经曰∶夏脉太过则病身热肤痛（心火克肺也），皮肤
索泽（素∶尽也，精血枯涸，故皮肤润泽之气皆尽也，即仲景皮肤甲错 乃干涩而不滑泽之谓）。
Yang Qi governs the four limbs. The Classics state: "The four limbs are the root of all Yang meridians." It is also stated: "When Yang Qi is knotted, swelling of the four limbs occurs." Furthermore: "The four limbs receive their Qi from the Stomach, but this Qi cannot reach the meridians directly; it must rely on the Spleen to be transmitted and thus nourish the limbs." When the Spleen is deficient, the four limbs become weak and unusable. It is also said: "Laziness and flaccidity of the four limbs indicate that the essence of the Spleen is not circulating properly."
The Liver governs the sinews (tendons), which are present in all meridians, generally connecting and belonging according to the course of the meridians. For details, refer to the chapter *Jing Jin* (Sinew Meridians) in the *Ling Shu*.
The Kidney governs the bones. In the body, it manifests as bones; in the zang organs, it corresponds to the Kidney. It is stated: "The external correspondence of the Kidney is the bone; its flourishing aspect is the hair." It is also said: "The Shaoyin meridian (Kidney meridian) is the pulse of winter, running deep within to warm the bone marrow." Patients with bone diseases should avoid bitter and sweet flavors and prolonged standing. The Classics say: "Excessive consumption of sweet flavor leads to bone pain and hair loss." It is also said: "Bitter flavor travels to the bone." Bone disease patients should not consume excessive bitter foods. It is also said: "Prolonged standing damages the bones, causing bone diseases to manifest with stiffness and inability to bend." The Classics state: "If the hand can flex but not extend, the pathology is in the sinews; if it can extend but not flex, the pathology is in the bones."
The Spleen governs the muscles. The Classics say: "The Spleen governs the muscles; in the body, it manifests as flesh; in the zang organs, it corresponds to the Spleen." It is also said: "When pathogenic factors affect the Spleen and Stomach, muscle pain occurs." Areas where muscle fibers converge sparsely are called "streams" (xi), referring to areas with less muscle mass; areas where muscle masses converge abundantly are called "valleys" (gu), referring to fleshy areas. Between the separated muscles and at the convergence of streams and valleys, Ying and Wei Qi circulate, and Zong Qi (Gathering Qi) gathers. Dampness injures the muscles, and excessive sweet flavor also injures the muscles. It is said: "Sweet flavor travels to the muscles." Those with muscle diseases should not eat excessive sweet foods. Prolonged sitting injures the muscles.
The skin belongs to the Lung. The Classics say: "The external correspondence of the Lung is the skin; its flourishing aspect is the body hair." If body hair breaks and nails wither, it indicates the exhaustion of Lung Qi. The Classics say: "The Taiyin meridian (Lung meridian) distributes Qi to warm the skin and hair." If Qi fails to nourish, the hair becomes scorched; if the skin and hair become scorched, body fluids are lost; once body fluids are lost, nails wither and hair breaks, leading to skin pain, which belongs to Heart Excess (Fire insulting Metal). The Classics say: "An excessive Summer pulse causes fever and skin pain (due to Heart Fire controlling Lung Metal); the skin becomes dry and lusterless ('su' means exhausted, indicating that due to the depletion of essence and blood, the moistening qi of the skin is entirely exhausted, i.e., what Zhang Zhongjing described as 'cracked skin,' meaning rough, dry, and unsmooth)."