指爪属筋余，脾为之运。小儿指尖冷，主惊厥。中指独热者属寒；中指独冷者，分男左
女右为痘痧发见之象。或其掌心冷而十指或开或合者，无治。(夏禹铸)
小儿拳四指己握，而大指加于四指上者，男顺女逆，小儿拳大指先屈于掌中，而四指加
于大
指上者，女顺男逆。小儿拳将大指插入食指叉而后握之，无论男女急慢惊风，均属险证，三
岁内至十岁外，皆可以此决之。(周于蕃)
指甲青者为心痛，又为肝气绝；指甲黑者筋绝；指甲白者死；指上有红丝缕者必夭。(
《大全》)
小儿热邪伤神，手如数物，谓十指屈伸不定，如数物之状然也。(《大全》)
凡病者手足、指甲下肉黑，八日死。(《大全》)
凡病者手掌肿而无纹，为无治。(《大全》)
抽衣撮空，循衣摸床，以及手撒不收者，皆无治。(周于蕃)
手热足冷，头痛发热者，为挟阴证。(周于蕃)
手热足冷，汗多妄言者，暑湿病也。(周于蕃)
足心热，主热；足胫冷，主寒。(《集成》)
足趺肿，呕吐头重者。不治。(《大全》)
足趺上肿，两膝大如斗者，十日死。(《大全》)
手背热与背上热者，外感；手心热与小腹热者，内伤。(周于蕃)
手心冷者腹中寒，手心热者虚火旺。(周于蕃)
足冷而晕者，气虚也。手足抽搐，身反向后者，痉病。(周于蕃)
额上及手足冷者为阴证。如不能久立，行则掉动者，骨败故也。(周于蕃)
仰睡而脚伸者热证，覆卧而脚蜷者寒证。(周于蕃)
手肿至腕，足肿至跗，面肿至颈，皆气虚不还，为最危。(周于蕃)
按∶脾主四肢。四肢厥逆，有寒有热，三阴证四肢厥冷，人所习见者寒厥也。厥尽也，
阳尽
而阴生，故四肢冷也。若热厥较寒厥尤多。《经》云∶热深厥亦深，热微厥亦微，同此厥逆
，寒热不分，生死立判，以之辨证，则手足尤为至要。(惕厉子)
指甲是筋的余气，由脾脏来运化。小儿指尖发冷，主病为惊厥。只有中指发热属于寒证；只有中指发冷的，需分男女：男看左手、女看右手，这是痘疹或痧疹将要发出的征象。如果掌心发冷，且十个手指有时张开有时握拢的，无法治疗。（夏禹铸）
小儿拳头四指已经握住，而大拇指覆盖在四指上面的，男孩为顺证，女孩为逆证；小儿拳头大拇指先弯曲在手掌中，而四指覆盖在大拇指上面的，女孩为顺证，男孩为逆证。小儿拳头将大拇指插入食指与中指之间的缝隙后握紧的，无论男孩女孩，无论是急惊风还是慢惊风，都属于险恶证候，三岁以内到十岁以外，都可以据此判断预后。（周于蕃）
指甲发青的，主心痛，又主肝气绝；指甲发黑的，主筋气绝；指甲发白的，主死亡；手指上有红色丝缕状的，必然夭折。（《医宗金鉴·幼科心法要诀》）
小儿热邪损伤神志，手部动作像数东西一样，指的是十个手指屈伸不定，如同数东西时的样子。（《医宗金鉴·幼科心法要诀》）
凡是患病者手足、指甲下的肉色发黑，八天内会死亡。（《医宗金鉴·幼科心法要诀》）
凡是患病者手掌肿胀且没有纹理的，无法治疗。（《医宗金鉴·幼科心法要诀》）
出现抽扯衣物、伸手抓空、摸衣寻床，以及手撒开不能收拢的，都无法治疗。（周于蕃）
手热足冷，伴有头痛发热的，为挟阴证（兼有阴经病变的外感证）。（周于蕃）
足心发热，主热证；足胫部发冷，主寒证。（《医宗金鉴·外科正宗》集成）
足背肿胀，伴有呕吐、头重的，无法治疗。（《医宗金鉴·幼科心法要诀》）
足背上肿胀，两膝肿大如斗的，十天内死亡。（《医宗金鉴·幼科心法要诀》）
手背发热和背部发热的，属外感；手心发热和小腹发热的，属内伤。（周于蕃）
脚冷且头晕的，是气虚。手足抽搐，身体向后反张的，是痉病。（周于蕃）
额头及手足发冷的，为阴证。如果不能久站，走路时摇晃不稳的，是骨骼败坏所致。（周于蕃）
仰卧睡觉时脚伸直的是热证，俯卧睡觉时脚蜷缩的是寒证。（周于蕃）
手肿至手腕，足肿至足背，面肿至颈部，都是气虚不能归元，属于最危险的证候。（周于蕃）
按语：脾主四肢。四肢厥逆（手脚冰冷），有寒证也有热证。三阴证（太阴、少阴、厥阴病）出现的四肢厥冷，人们常见的是寒厥。厥，就是尽的意思，阳气耗尽而阴气内生，所以四肢发冷。然而热厥比寒厥更多见。《内经》说：热邪越深，厥冷也越深；热邪越微，厥冷也越微。同样是厥逆，如果不分辨寒热，生死立判，用此来辨证，则观察手足尤为关键。（惕厉子）
The nails are the surplus of the sinews (tendons), governed by the Spleen's transportation and transformation. Cold fingertips in infants indicate Jue (convulsions). Heat isolated to the middle finger indicates a cold pattern; cold isolated to the middle finger, differentiated by gender (left hand for males, right hand for females), is a sign that variola (smallpox) or sand-rash (scarlet fever-like illness) is about to erupt. If the palm is cold and the ten fingers alternately open and close, it is incurable. (Xia Yuzhu)
When an infant's fist has four fingers curled inward with the thumb resting on top, it is a favorable prognosis for males and unfavorable for females. When the infant's fist has the thumb curled inside the palm first, with the four fingers resting on top of the thumb, it is a favorable prognosis for females and unfavorable for males. If the infant inserts the thumb into the cleft between the index and middle fingers before closing the fist, regardless of gender, whether acute or chronic Feng (wind syndrome/convulsion), it is a critical condition. This diagnostic sign applies to children from under three years old up to over ten years old. (Zhou Yufan)
Blueish nails indicate Heart pain and also Liver Qi exhaustion; black nails indicate Sinew exhaustion; white nails indicate death; red thread-like markings on the fingers indicate premature death. (*Yi Zong Jin Jian*)
Heat pathogen damaging the Spirit in infants causes the hands to move as if counting objects, meaning the ten fingers flex and extend irregularly, resembling the motion of counting. (*Yi Zong Jin Jian*)
In any disease, if the flesh under the fingernails and toenails turns black, death occurs within eight days. (*Yi Zong Jin Jian*)
If the palms are swollen and lack creases, it is incurable. (*Yi Zong Jin Jian*)
Pulling at clothes, grasping at empty air, touching clothes and beds, and hands flaccidly open and unable to close are all incurable. (Zhou Yufan)
Hot hands and cold feet accompanied by headache and fever indicate a mixed Yin syndrome (exterior contraction involving the Yin meridians). (Zhou Yufan)
Hot hands and cold feet with profuse sweating and delirious speech indicate Summerheat-Dampness disease. (Zhou Yufan)
Hot soles indicate heat patterns; cold calves indicate cold patterns. (*Ji Cheng*)
Swelling of the dorsum of the foot accompanied by vomiting and heavy head is incurable. (*Yi Zong Jin Jian*)
Swelling of the dorsum of the foot with knees enlarged like a bucket indicates death within ten days. (*Yi Zong Jin Jian*)
Heat in the back of the hands and back indicates exterior contraction; heat in the palms and lower abdomen indicates interior injury. (Zhou Yufan)
Cold palms indicate cold in the abdomen; hot palms indicate flourishing deficiency fire. (Zhou Yufan)
Cold feet with dizziness indicate Qi deficiency. Convulsions of the limbs with the body arching backward indicate Jing (spasm/tetanus) disease. (Zhou Yufan)
Cold forehead and extremities indicate a Yin syndrome. Inability to stand for long periods and unsteady gait when walking indicate bone deterioration. (Zhou Yufan)
Sleeping supine with legs extended indicates a heat pattern; sleeping prone with legs curled indicates a cold pattern. (Zhou Yufan)
Swelling of hands to the wrists, feet to the dorsum, and face to the neck indicates Qi deficiency failing to return to its source, which is the most critical condition. (Zhou Yufan)
Note: The Spleen governs the four limbs. Limb Jue (cold extremities) can be due to cold or heat. The limb coldness seen in Three Yin syndromes (Taiyin, Shaoyin, Jueyin diseases) is commonly known as Cold Jue. "Jue" means exhaustion; when Yang Qi is exhausted and Yin arises, the limbs become cold. However, Heat Jue is more common than Cold Jue. The *Classic* states: "The deeper the heat, the deeper the Jue; the slighter the heat, the slighter the Jue." In cases of identical Jue, failing to distinguish between cold and heat leads to immediate determination of life or death. Therefore, in differentiation, observing the hands and feet is paramount. (Ti Li Zi)