If the pulse is floating and wiry, it indicates Wind; if soggy and weak, Dampness; if surging and rapid, Heat; if slow and choppy, Cold; if faint and slippery, Deficiency; if firm and hard, Excess. A knotted pulse arises from Qi stagnation; a scattered pulse from excessive worry; a tight pulse from anger; a fine pulse from sorrow.

This disease is primarily caused by Dampness. In people of the South, taking coolness in the wind, engaging in sexual intercourse after intoxication, sitting for long periods on damp ground, or wearing footwear contaminated with Wind-Damp toxic vapors, leads to weakness of Blood and Qi. Pathogenic factors and healthy Qi run parallel through the interstices (Couli). When pathogenic factors are strong and healthy Qi is weak, Blood and Qi flow becomes obstructed. Obstruction leads to Spleen deficiency; deficiency leads to weakness, and the disease manifests as fever. Limb soreness, pain, and irritability result from contracting cold-dampness during summer months; limb contracture and tendon stiffness result from contracting cold-dampness during winter months. Symptoms include swelling of the shins, numbness of the lower abdomen, headache, vexation, phlegm obstruction, vomiting and regurgitation, alternating chills and fever, and obstruction of urination and defecation. In severe cases, the pathogen attacks the Heart with urgent severity, requiring immediate treatment without delay. This is an obstruction disorder. If the obstruction has not yet fully formed, it should be promoted and unblocked using damp-resolving herbs such as Cangzhu (Atractylodis Rhizoma) and Chuanbai (Phellodendri Cortex). If the obstruction has already formed, bad blood should be drained via bian stone therapy before further treatment. Hongjiaojiao (Foot Qi/Jiaji) attacking the Heart is due to Blood deficiency combined with Damp-Heat; treatment suits Siwu Tang (Four Substances Decoction) added with Baipi (Phellodendri Cortex). Tendon spasms and pain indicate that Blood has been affected by Damp-Heat; treatment adds Taoren (Persicae Semen), Huangqin (Scutellariae Radix), and Lian (Coptidis Rhizoma). For Phlegm accumulation flowing into collaterals, add Jiangzhi (Ginger Juice), Zhuli (Bamboo Sap), and Nanting (Arisaematis Rhizoma). Diseases in the North are caused by Damp-Heat from drinking Tongru (a type of milk product) and rich wine flowing downward, accumulating over time to cause swelling, fullness, and pain; treatment requires purgative drugs to drain and disperse the pathogen.

Danggui Qiantong Tang (Angelica Sinensis Decoction for Painful Obstruction): Treats painful obstruction of limbs and joints due to Damp-Heat, heaviness of shoulders and back, discomfort in chest and hypochondrium, body pain, and swelling.
Ingredients: Qianghuo (Notopterygii Rhizoma et Radix), Huangqin (Scutellariae Radix, wine-processed), Gancao (Glycyrrhizae Radix et Rhizoma, honey-fried), Yichen (Artemisiae Scopariae Herba, wine-fried), Chuan Gui (Angelicae Sinensis Radix, each 5 qian), Renshen (Ginseng Radix), Kushen (Sophorae Flavescentis Radix, wine-washed), Shengma (Cimicifugae Rhizoma), Gange (Puerariae Radix), Cangzhu (Atractylodis Rhizoma, each 2 liang), Zhimu (Anemarrhenae Rhizoma, wine-washed), Fangfeng (Saposhnikoviae Radix), Zexie (Alismatis Rhizoma, each 3 qian), Zhuling (Polyporus), Baizhu (Atractylodis Macrocephalae Rhizoma, each 1.5 qian).
Decoct and take orally.

Qianghuo Daozhi Tang (Notopterygium Decoction for Guiding Stagnation): Treats the aforementioned symptoms accompanied by obstruction of urination and defecation. Use this medicine first to guide out stagnation, then consume the previous formula and treat Northern-type Foot Qi.
Ingredients: Qianghuo (Notopterygii Rhizoma et Radix), Duhuo (Angelicae Pubescentis Radix, each 5 qian), Fangji (Stephaniae Tetrandrae Radix), Chuan Gui (Angelicae Sinensis Radix, each 3 qian), Dahuang (Rhei Radix et Rhizoma, wine-roasted, 1 liang), Zhishi (Aurantii Fructus, bran-fried, 3 qian).

Secret Formula: Treats Damp-Heat.
Ingredients: Shengdi (Rehmanniae Radix), Huangbai (Phellodendri Cortex, wine-processed), Baizhu (Atractylodis Macrocephalae Rhizoma), Fangji (Stephaniae Tetrandrae Radix), Chuanxiong (Ligustici Chuanxiong Rhizoma), Binglang (Arecae Semen), Cangzhu (Atractylodis Rhizoma, salt-fried), Xijiao (Rhinoceoris Cornu), Gancao (Glycyrrhizae Radix et Rhizoma), Mutong (Akebiae Caulis).
For excess heat, add Huangqin (Scutellariae Radix) and Lian (Coptidis Rhizoma); for phlegm, add Zhuli (Bamboo Sap) and Jiangzhi (Ginger Juice); during fever, add Shigao (Gypsum Fibrosum); for solid stool, add Taoren (Persicae Semen); for difficult urination, add Niuxi (Achyranthis Bidentatae Radix).

Food Accumulation Flowing Into Collaterals:
Ingredients: Cangzhu (Atractylodis Rhizoma), Huangbai (Phellodendri Cortex), Fangji (Stephaniae Tetrandrae Radix), Nanting (Arisaematis Rhizoma), Chuanxiong (Ligustici Chuanxiong Rhizoma), Baizhi (Angelicae Dahuricae Radix), Binglang (Arecae Semen), Xijiao (Rhinoceoris Cornu), Niuxi (Achyranthis Bidentatae Radix). Add Guiban (Testudinis Carapax et Plastrum) for Blood deficiency.

Chushi Dan (Dampness-Expelling Pill): Treats various types of Dampness.
Ingredients: Chenpi (Citri Reticulatae Pericarpium, 2 liang), Daji (Euphorbiae Pekinensis Radix, fried, half liang), Heiqiu (Crotonis Fructus, fried, 3 qian), Gansui (Kansui Radix), Binglang (Arecae Semen), Chishao (Paeoniae Radix Rubra), Lingxian (Spatholobi Caulis), Zexie (Alismatis Rhizoma), Tingli (Descurainiae Semen seu Lepidii Semen, each 1 liang), Ruxiang (Olibanum, separately ground), Moyao (Myrrha, each 5 qian).
Make pills with paste, size of wutong seeds. Take 50 pills initially, increasing to 100 pills, with warm water. Avoid wet flour products.

Hua Tuo’s Discussion:
Internally, emotional disturbances such as worry, thought, joy, and anger, along with cold, heat, pathogenic, and toxic qi, inject into the feet and knees. The condition resembles various wind diseases and is called Hongjiaojiao (Foot Qi/Jiaji).
Externally, incorrect qi from Wind, Cold, Summerheat, and Dampness strikes the feet and knees, also called Hongjiaojiao (Foot Qi/Jiaji). The treatment principle states: For Excess conditions, promote drainage; for Deficiency conditions, tonify. Six Exogenous Pathogens are dispersed according to the Six Methods; Seven Emotions are dissipated according to the Six Qi.

Theory of Three Causes: Caused by invasion of Wind, Cold, Summerheat, Dampness, and toxic vapors. Wind causes a floating pulse; Cold causes a tight pulse; Dampness causes a fine pulse; Summerheat causes a surging pulse. Exterior patterns present with a floating pulse; Interior patterns present with a deep pulse. Wind causes pain; Dampness causes heaviness; Summerheat causes vexation; Wind causes wandering sensations. Treatment follows the meridian invaded. For example, pain in the head, neck, waist, and spine belongs to the Taiyang Meridian; suitable herbs include Mahuang (Ephedrae Herba) and Qianghuo (Notopterygii Rhizoma et Radix). Other cases follow this analogy.