《内经》言挛皆属肝，肝主身之筋故也。又阳明之复，甚则入肝，惊骇筋挛。又脾移寒于肝，痈
肿筋挛。有热、有寒、有虚、有实。热挛者，经所谓肝气热则筋膜干，筋膜干则筋急而挛。又云∶因
于湿，首如裹，湿热不攘，大筋软短，小筋弛长，软短为拘，弛长为痿之类是也。（丹溪云∶大筋软
短者，热伤血不能养筋，故为拘挛。小筋弛长者，湿伤筋不能束骨，故为痿弱。）筋膜干者用生 、
当归之属濡之。大筋软短者，薏苡仁散主之。《衍义》云∶筋急拘挛有两等，《素问》大筋受热则缩
而短，故挛急不伸，则可用薏苡仁。若《素问》言因寒筋急，不可用也。寒挛者，经所谓寒多则筋拳
骨痛者是也。乌头汤、《千金》薏苡仁汤。虚挛者，经所谓虚邪搏于筋则为筋拳。又云∶脉弗荣则筋
急。
又仲景云∶血虚则筋急。此皆血脉弗荣于筋而筋成挛。故丹溪治挛用四物加减，《本事》治筋急极用
养血地黄丸，盖本乎此。实挛者，丹溪治一村夫，背伛偻而足挛，已成废人，诊其脉两手皆沉弦而涩，
遂以戴人煨肾散与之，上吐下泻，过月余久，吐泻交作，如此凡三帖，然后平复。东垣治董监军，腊
月大雪初霁出外，忽觉有风气暴仆，诊得六脉俱弦甚，按之洪实有力，其证手挛急，大便秘涩，面赤
热，此风寒始至加于身也。四肢者脾也，以风寒之邪伤之，则搐急而挛痹，乃风淫末疾而寒在外也。
《内经》云∶寒则筋挛，正此谓也。本人素多饮酒，内有实热，乘于肠胃之间，故大便闭涩而面赤热。
内则手足阳明受邪，外则足太阴脾经受风寒之邪。用桂枝、甘草以却其寒邪，而缓其急搐；用黄柏之
苦寒滑以泻实而润燥，急救肾水；用升麻、葛根以升阳气，行手足阳明之经，不令遏绝；更以桂枝辛
热，入手阳明之经为引；用润燥复以芍药、甘草，专补脾气，使不受风寒之邪而退木邪，专益肺金也；
加人参以补元气为之辅佐；加当归身去里急而和血润燥，名之曰活血通经汤。更令暖房中近火摩搓其
手乃愈。《本事方》春夏服养血地黄丸、秋服羚羊角汤、冬服乌头汤。下虚则挟腰膝疼痛，防风散。
上虚则挟心神烦热，不得睡卧，麦门冬散、黄
丸。外感风湿四肢拘挛，苍耳子捣末煎服。酒煮木瓜令烂，研作粥浆，用裹筋急处，冷即易。灸筋急
不能行，内踝筋急，灸内踝四十壮，外踝筋急，灸外踝三十壮，立愈。
《黄帝内经》指出，各种筋脉拘挛的病证都归属于肝，因为肝主管全身的筋脉。另外，当阳明经之气发生复气病变时，严重时会影响肝脏，出现惊骇、筋脉拘挛的症状。还有脾脏将寒邪转移至肝脏，会导致痈肿和筋脉拘挛。这些情况有热证、寒证、虚证、实证之分。
热性拘挛，正如经典所说：“肝气热则筋膜干燥，筋膜干燥则筋脉紧急而拘挛。”又说：“因湿气侵袭，头部感觉像被包裹一样，若湿热不能清除，大筋会缩短变软，小筋会松弛延长，缩短导致拘急，松弛导致痿弱”之类的情形。（朱丹溪说：大筋缩短变软，是因为热邪损伤血液，无法滋养筋脉，所以产生拘挛；小筋松弛延长，是因为湿邪损伤筋脉，无法约束骨骼，所以产生痿弱。）对于筋膜干燥的情况，使用生地黄、当归等药物来濡养筋脉。对于大筋缩短变软的情况，主要使用薏苡仁散治疗。《本草衍义》说：筋脉紧急拘挛有两种情况，《素问》中提到大筋受热则收缩变短，所以拘急不能伸展，这时可以使用薏苡仁。如果是《素问》所说的因寒邪导致的筋脉紧急，则不能使用薏苡仁。
寒性拘挛，正如经典所说：“寒气多则筋脉蜷曲、骨骼疼痛。”可用乌头汤或《千金方》中的薏苡仁汤治疗。
虚性拘挛，正如经典所说：“虚邪搏结于筋脉，则导致筋脉蜷曲。”又说：“血脉不荣养则筋脉紧急。”张仲景也说：“血虚则筋脉紧急。”这些都是因为血脉不能荣养筋脉而导致筋脉拘挛。因此，朱丹溪治疗拘挛时使用四物汤加减，《本事方》治疗极度筋脉紧急时使用养血地黄丸，其理论依据就在于此。
实性拘挛，例如朱丹溪曾治疗一个村夫，背部佝偻且足部拘挛，已成废人，诊察其脉象两手皆沉弦而涩，于是给他服用戴人煨肾散，通过催吐和泻下疗法，经过一个多月，吐泻交替发作，如此共服三剂药后，身体才恢复平复。李东垣曾治疗董监军，在腊月大雪初晴外出时，忽然感觉风气猛烈而跌倒，诊得六脉皆弦紧有力，按之洪大坚实，症状表现为手部拘急、大便秘结不畅、面部发红发热，这是风寒之邪刚开始侵袭身体。四肢属于脾脏管辖，风寒邪气伤害了它，就会导致抽搐紧急、拘挛麻痹，这属于风邪侵犯肢体末端引发的疾病，而寒邪在体表。《内经》说：“寒则筋脉拘挛”，正是这个意思。此人平时饮酒较多，体内有实热，乘积在肠胃之间，所以大便闭结不畅且面部发红发热。内部是手足阳明经受邪，外部是足太阴脾经受风寒邪气。使用桂枝、甘草来驱除寒邪，并缓解紧急抽搐；使用黄柏的苦寒滑利之性来泻实热并润燥，急救肾水；使用升麻、葛根来提升阳气，疏通手足阳明经，防止气机遏绝；再用桂枝的辛热之性，作为引经药进入手阳明经；用润燥的方法配合芍药、甘草，专门补益脾气，使脾不受风寒邪气侵害从而退去木邪（肝木），专门益助肺金；加入人参来补益元气作为辅助；加入当归身以去除里急感并调和血液、润燥，将此方命名为活血通经汤。还让他住在温暖的房间里，靠近火源摩擦搓揉双手，这才痊愈。《本事方》记载：春夏季节服用养血地黄丸，秋季服用羚羊角汤，冬季服用乌头汤。
下部虚弱则伴有腰膝疼痛，用防风散治疗。上部虚弱则伴随心神烦热、无法入睡，用麦门冬散、黄丸治疗。外感风湿导致的四肢拘挛，用苍耳子捣碎成末煎服。用酒煮木瓜直至烂熟，研磨成粥浆，用来包裹筋脉紧急的部位，冷了即更换。对于筋脉紧急导致无法行走的情况，可艾灸；内踝筋脉紧急，灸内踝四十壮；外踝筋脉紧急，灸外踝三十壮，立即痊愈。
The *Huangdi Neijing* (Yellow Emperor's Inner Canon) states that all types of tendon contracture (*Jin Luan*) are associated with the Liver, because the Liver governs the tendons of the body. Furthermore, when there is a rebounding pathogenic factor in the Yangming channel, severe cases may affect the Liver, resulting in fright and tendon contracture. Additionally, if Cold from the Spleen transfers to the Liver, it can cause carbuncles and swelling along with tendon contracture. These conditions can be categorized into Heat, Cold, Deficiency, and Excess patterns.
In cases of Heat-induced contracture, as stated in the classics: "When Liver Qi is hot, the fascia becomes dry; when the fascia is dry, the tendons become tight and contract." It also says: "Affected by Dampness, the head feels wrapped; if Damp-Heat is not dispelled, the large tendons become soft and short, while the small tendons become lax and long. Shortening leads to constraint (*Ju*), while laxity leads to flaccidity (*Wei*)." (Zhu Danxi said: Large tendons becoming soft and short indicates that Heat has damaged the Blood, failing to nourish the tendons, thus causing contracture. Small tendons becoming lax and long indicates that Dampness has damaged the tendons, failing to bind the bones, thus causing flaccidity.) For cases of dry fascia, herbs such as Sheng Di Huang (Rehmanniae Radix Preparata) and Dang Gui (Angelicae Sinensis Radix) are used to moisten and nourish. For cases where large tendons are soft and short, Yi Yi Ren San (Coix Seed Powder) is the primary prescription. The *Bencao Yan yi* (Supplement to Materia Medica) states that there are two types of tendon urgency and contracture: according to the *Suwen*, when large tendons are affected by Heat, they shrink and shorten, causing urgency and inability to extend; in such cases, Yi Yi Ren (Coicis Semen) can be used. However, if the condition is due to Cold as described in the *Suwen*, Yi Yi Ren should not be used.
In cases of Cold-induced contracture, as stated in the classics: "Excessive Cold causes the tendons to curl and the bones to ache." Wutou Tang (Aconite Decoction) or Yi Yi Ren Tang (Coix Seed Decoction) from the *Qianjin Fang* can be used.
In cases of Deficiency-induced contracture, as stated in the classics: "Deficient pathogens attacking the tendons result in tendon curling." It also says: "If the vessels do not nourish, the tendons become urgent." Zhang Zhongjing also stated: "Blood deficiency leads to tendon urgency." All these indicate that tendon contracture arises because the blood vessels fail to nourish the tendons. Therefore, Zhu Danji treated contracture using Si Wu Tang (Four Substances Decoction) with modifications. The *Ben Shi Fang* treated extreme tendon urgency with Yang Xue Di Huang Wan (Blood-Nourishing Rehmannia Pill), based on this principle.
In cases of Excess-induced contracture, for example, Zhu Danji once treated a villager who was hunchbacked and had contracted feet, rendering him disabled. His pulse was deep, wiry, and choppy in both hands. Zhu administered Dai Ren Wei Shen San (Dai Person's Roasted Kidney Powder). Through induced vomiting and purging, over more than a month, vomiting and diarrhea alternated. After three doses of this regimen, the patient recovered. Li Dongyuan once treated Supervisor Dong. In the twelfth lunar month, after heavy snow cleared, Dong went outside and suddenly felt a violent wind causing him to collapse. His six pulses were extremely wiry, forceful and full upon pressure. His symptoms included hand contracture, constipation, redness, and heat in the face. This indicated that Wind-Cold had just invaded the body. The limbs are governed by the Spleen; when injured by Wind-Cold pathogens, they twitch, become urgent, and suffer from contracture and numbness. This is a disease of the extremities caused by excessive Wind, with Cold remaining on the exterior. The *Neijing* states: "Cold causes tendon contracture," which applies here. The patient usually drank alcohol, leading to internal Excess Heat accumulating in the intestines and stomach, causing constipation and facial redness/heat. Internally, the Hand and Foot Yangming channels were affected; externally, the Foot Taiyin Spleen channel was affected by Wind-Cold. Guizhi (Cinnamomi Ramulus) and Gancao (Glycyrrhizae Radix et Rhizoma) were used to expel Cold and relieve urgency/twitching. Huangbai (Phellodendri Cortex), bitter, cold, and slippery, was used to drain Excess and moisten dryness, urgently saving Kidney Water. Shengma (Cimicifugae Rhizoma) and Gegen (Puerariae Lobatae Radix) were used to raise Yang Qi and circulate the Hand and Foot Yangming channels, preventing stagnation. Guizhi, being acrid and hot, served as a guiding herb entering the Hand Yangming channel. Shaoyao (Paeoniae Radix Alba) and Gancao were added to moisten dryness and specifically tonify Spleen Qi, protecting against Wind-Cold and subduing Wood (Liver) to benefit Metal (Lung). Renshen (Ginseng Radix) was added to tonify Yuan Qi as an assistant. Danggui Shen (Angelicae Sinensis Radix Root) was added to relieve interior urgency, harmonize Blood, and moisten dryness. This formula was named Huoxue Tongjing Tang (Invigorate Blood and Unblock Channels Decoction). He also instructed the patient to stay in a warm room near fire and rub his hands until healed. The *Ben Shi Fang* records taking Yang Xue Di Huang Wan in Spring and Summer, Lingyang Jiao Tang (Antelope Horn Decoction) in Autumn, and Wutou Tang in Winter.
Lower Deficiency accompanied by lower back and knee pain is treated with Fangfeng San (Saposhnikoviae Powder). Upper Deficiency accompanied by mental restlessness, heat, and insomnia is treated with Maimendong San (Ophiopogonis Powder) and Huang Wan (Yellow Pill). External contraction of Wind-Dampness causing four-limb constraint is treated by decocting Cang Er Zi (Xanthii Fructus) powder. Mu Gua (Chaenomelis Fructus) boiled in wine until soft, ground into porridge, and applied to the contracted area (replacing when cold) is also effective. For tendon contracture preventing walking, moxibustion is used: forty moxa cones on the medial malleolus for medial ankle contracture, and thirty moxa cones on the lateral malleolus for lateral ankle contracture, resulting in immediate cure.