膀胱脉抵腰，肾脉入腰。又经曰∶腰者、肾之府也，转摇不能，肾将惫矣。是
腰痛乃肾与膀胱之病也。太阳经虚，则风寒湿诸客邪皆得为患，而肾虚之所患尤多。
腰肢痿弱，身体疲倦，脚膝酸软，脉或洪或细，皆无力，痛亦悠悠隐
隐不甚，是其候也。分寒热二证，脉细无力，气怯弱，小便清利，为阳虚，宜肾气丸（
见虚损）、橘香丸、生料鹿茸丸（见血）之类。仍以茴香炒研，猪腰切片，勿
令断，糁末其内，纸裹煨热，黄酒下。脉洪而无力，小便黄赤，虚火时炎，为阴虚。
东垣所谓醉以入房，损其真阴，则肾气热，热则腰脊痛不能举，久则髓减骨枯，发
为骨痿，六味丸（见虚损）、滋肾丸（见小便不通）、封髓丹（见遗精）之类。疟痢后，
月经后痛者，多
属虚，于补气血药加杜仲、侧柏叶。丹溪云∶久腰痛，必用官桂开之，痛方止。胁
腹痛亦然。有风有寒，有湿有热，有闪挫，有瘀血，有滞气，有痰积。伤于风，
脉必浮，或左或右，痛无常处，牵引两足，羌、防、秦艽必用。感寒而痛，腰
间冷如冰，脉必紧，得热则减，得寒则增，姜附汤（见中寒）加辣桂、杜仲，外用摩
腰膏。伤于湿，如坐水中，脉必缓，遇天阴或久坐（久坐则湿凝）必发，身体肿，渗湿汤、
肾着汤。（并见伤湿。）体重腰冷，饮食如故，小便自利，名肾着，（寒湿之气，凝着
不行。）治宜
除湿兼温散。风湿，独活寄生汤。湿热，苍术汤、独活汤、羌活汤。闪挫或跌扑损伤而痛。乳香
痛散，五积散（见中寒）加桃仁、大黄、苏木各一钱，倍当归。或以茴香根同红曲擂烂，热酒
调服。若因劳役负重而痛，和气饮（见肿胀），或普贤正气散。瘀血脉必涩，转侧若刀锥之刺，大
便黑，日轻夜重，桃仁酒调黑神散，或四物（并见血）。加桃仁、红花之属。气滞脉必沉，乌
药顺气散（见中风）、人参顺气散。痰注脉必滑，或沉弦，二陈（见痰）加南星、香附、乌药、
枳壳、威灵仙治痛要药，为末，每用二钱，糁猪腰内煨吃，热酒下，微利为度。
杜仲（姜汁炒断丝）、黑丑、破故纸、桃仁（炒，去皮尖）、玄胡索，等份为末，酒煮面糊，胡
桃肉和丸，桐子大，空心温酒或白汤下五七十丸，宜下者用之。腰痛虽属肾与膀胱，
然有子病累母者，故郁怒伤肝亦致腰痛，宜调肝散。有土病及水者，故忧思伤
脾，亦为腰痛，沉香降气汤（见气）和调气散（见中气。）腰痛面忽红忽黑，为心肾交争，难治
之证也。
膀胱的经脉下行至腰部，肾的经脉进入腰部。又经典记载：腰是肾的外府，如果腰部转动摇动困难，说明肾气将要衰败了。因此腰痛是肾与膀胱的疾病。太阳经虚弱，那么风寒湿等外邪都容易侵袭致病，而肾虚导致的患病尤其多。
腰部肢体痿弱无力，身体疲倦，脚膝酸软，脉象或洪大或细弱，但都没有力气，疼痛也是隐隐约约、不太剧烈，这是其证候表现。分为寒热两证：脉象细弱无力，气息怯弱，小便清长通畅，属于阳虚，适宜使用肾气丸（见虚损章节）、橘香丸、生料鹿茸丸（见血证章节）之类方剂。仍以茴香炒后研末，猪腰切片，不要切断，将药末撒入其中，用纸包裹煨热，用黄酒送服。脉象洪大但无力，小便黄赤，虚火时常上炎，属于阴虚。东垣所说的醉酒后行房事，损伤真阴，导致肾气发热，热则腰脊疼痛不能抬起，时间久了则髓减骨枯，发为骨痿，适宜使用六味丸（见虚损章节）、滋肾丸（见小便不通章节）、封髓丹（见遗精章节）之类方剂。疟疾痢疾之后，月经后出现疼痛的，多属于虚证，在补气血的药物中加入杜仲、侧柏叶。丹溪说：久治不愈的腰痛，必须用官桂来开通，疼痛才能停止。胁痛腹痛也是如此。有风邪、有寒邪、有湿邪、有热邪、有闪挫扭伤、有瘀血、有滞气、有痰积。
伤于风邪，脉象必定浮，或在左或在右，疼痛没有固定位置，牵引双腿，羌活、防风、秦艽是必用的药物。感受寒邪而疼痛，腰间冷如冰，脉象必定紧，遇热则减轻，遇寒则加重，可用姜附汤（见中寒章节）加辣桂、杜仲，外用摩腰膏。伤于湿邪，感觉像坐在水中，脉象必定缓，遇到阴天或久坐（久坐则湿气凝结）必定发作，身体浮肿，可用渗湿汤、肾着汤。（均见伤湿章节。）体重且腰部寒冷，饮食正常，小便自利，名为肾着病，（寒湿之气，凝滞附着不行。）治疗宜除湿兼温散。风湿证，用独活寄生汤。湿热证，用苍术汤、独活汤、羌活汤。
闪挫或跌扑损伤引起的疼痛。可用乳香痛散，五积散（见中寒章节）加桃仁、大黄、苏木各一钱，加倍当归用量。或者用茴香根同红曲捣烂，热酒调服。若因劳役负重引起的疼痛，用和气饮（见肿胀章节），或普贤正气散。
瘀血阻滞，脉象必定涩，转身侧卧如同刀锥刺割，大便黑色，白天轻晚上重，用桃仁酒调服黑神散，或四物汤（均见血证章节）。加入桃仁、红花之类的药物。气机阻滞，脉象必定沉，用乌药顺气散（见中风章节）、人参顺气散。痰浊注滞，脉象必定滑，或沉弦，用二陈汤（见痰证章节）加南星、香附、乌药、枳壳、威灵仙（治疗疼痛的要药），研为末，每次用二钱，撒入猪腰内煨熟吃下，热酒送服，以轻微腹泻为度。
杜仲（姜汁炒断丝）、黑丑、破故纸、桃仁（炒，去皮尖）、玄胡索，等份研为末，酒煮面糊，和胡桃肉制成丸药，如梧桐子大，空腹时温酒或白开水送服五七十丸，适合需要通下的患者使用。
腰痛虽然属于肾与膀胱，但有子病累及母的情况，所以郁怒伤肝也会导致腰痛，适宜用调肝散。有土病及水的关系，所以忧思伤脾，也会引起腰痛，用沉香降气汤（见气证章节）合调气散（见中气章节）。腰痛面色忽然发红忽然发黑，是心肾交争的表现，属于难治的证候。
The Bladder meridian descends to the waist, and the Kidney meridian enters the waist. Furthermore, the classics state: "The waist is the mansion of the Kidney; if turning and shaking are difficult, the Kidney Qi is about to fail." Therefore, low back pain is a disease of the Kidney and Bladder. When the Taiyang meridian (Greater Yang) is deficient, pathogenic factors such as wind, cold, and dampness can easily invade and cause illness, with deficiency of the Kidney leading to particularly frequent occurrences.
Symptoms include flaccidity and weakness of the waist and limbs, bodily fatigue, soreness and weakness of the feet and knees, pulse either surging or fine but always forceless, and pain that is dull, hidden, and not severe. These are its characteristic signs. It is divided into two syndromes: cold and heat. A fine and forceless pulse, timid Qi, and clear, free urination indicate Yang deficiency. Suitable formulas include Shenqi Wan (Kidney Qi Pill, see Deficiency Damage), Juxiang Wan (Citrus Fragrance Pill), and Shengliao Lurong Wan (Raw Material Deer Antler Pill, see Blood Disorders). Additionally, use Fennel seeds stir-fried and powdered, sliced pig kidneys (not cut through), sprinkle the powder inside, wrap in paper, and bake until hot; take with yellow wine. A surging yet forceless pulse, yellow-red urine, and occasional flare-ups of deficient fire indicate Yin deficiency. Dongyuan stated that indulgence in alcohol and sexual intercourse damages true Yin, causing Heat in the Kidney Qi. Heat leads to pain in the lower back and spine preventing lifting, and over time, depletion of marrow and withering of bones, developing into Bone Wei (Bone Flaccidity). Suitable formulas include Liuwei Wan (Six-Ingredient Pill, see Deficiency Damage), Zishen Wan (Nourish Kidney Pill, see Difficulty in Urination), and Fengsui Dan (Seal Marrow Elixir, see Spermatorrhea). Pain occurring after malaria/dysentery or menstruation mostly belongs to deficiency; add Eucommia Bark (Duzhong) and Biota Leaf (Cebaiye) to Qi- and Blood-tonifying herbs. Danxi said: For chronic low back pain, Guigui (Cinnamon Bark) must be used to open the pathways for the pain to cease. The same applies to hypochondriac and abdominal pain. Causes include Wind, Cold, Dampness, Heat, sprain/strain, Blood stasis, Qi stagnation, and Phlegm accumulation.
Wind injury results in a floating pulse, pain on either the left or right side, pain without fixed location, radiating to both legs; Qianghuo (Notopterygium Rhizome), Fangfeng (Saposhnikovia Root), and Qinjiao (Gentiana Macrophylla Root) are essential. Cold injury causes pain with the waist feeling cold as ice, a tight pulse, relief with heat, and aggravation with cold; treat with Jiangfu Tang (Ginger and Aconite Decoction, see Middle Cold) plus Lagui (Spicy Cinnamon) and Duzhong, externally apply Moyao Gao (Waist Rubbing Plaster). Dampness injury feels like sitting in water, a slow pulse, onset during cloudy weather or prolonged sitting (prolonged sitting condenses dampness), bodily swelling; treat with Shenshi Tang (Leach Dampness Decoction) or Shen Zhuo Tang (Kidney Fixation Decoction) (both see Injury by Dampness). Heavy body, cold waist, normal diet, and free urination are named Shen Zhuo (Kidney Fixation), where Cold-Damp Qi condenses and adheres without moving. Treatment should dispel dampness while warming and dispersing. For Wind-Damp, use Duhuo Jisheng Tang (Angelica Pubescens and Hosta Root Decoction). For Damp-Heat, use Cangzhu Tang (Atractylodes Rhizome Decoction), Duhuo Tang, or Qianghuo Tang.
Pain from sprains or falls: Use Ruxiang Tong San (Frankincense Pain Powder), or Wuji San (Five Accumulations Powder, see Middle Cold) plus Taoren (Peach Kernel), Dahuang (Rhubarb Root), and Sumu (Sappan Wood) each 1 qian, double the dose of Danggui (Angelica Sinensis). Alternatively, pound Fennel root with Red Yeast Rice, mix with hot wine, and take. Pain from labor and heavy lifting: Use Heqi Yin (Harmonize Qi Drink) or Puxian Zhengqi San.
Blood stasis presents with a choppy pulse, pain upon turning like knife or awl piercing, black stool, lighter by day and heavier by night; treat with Tao Ren Jiu Tiao Heishen San (Black God Powder mixed with Peach Kernel Wine) or Siwu Tang (Four Substances Decoction, see Blood Disorders), adding Taoren (Peach Kernel) and Honghua (Safflower). Qi stagnation presents with a deep pulse; treat with Wuyao Shunqi San (Lindera Smooth Qi Powder) or Renshen Shunqi San (Ginseng Smooth Qi Powder). Phlegm accumulation presents with a slippery or deep-wiry pulse; treat with Erchen Tang (Two Aged Herbs Decoction, see Phlegm) plus Nanxing (Arisaema Rhizome), Xiangfu (Cyperus Rhizome), Wuyao (Lindera Root), Zhike (Bitter Orange Fruit), and Weilingxian (Syneilesis Aconitifolia Root), an important herb for pain. Grind to powder, use 2 qian per dose, sprinkle inside pig kidney, bake and eat, take with hot wine, stopping when mild diarrhea occurs.
Prepare Duzhong (stir-fried with Ginger Juice until fibers break), Heiqiu (Black Morning Glory Seed), Poguzhi (Cistanche Stem), Taoren (Peach Kernel, stir-fried, skin and tip removed), and Yuanhusuo (Corydalis Rhizome) in equal parts. Grind to powder, make pills using wine-boiled wheat paste and Walnut Meat, size of paulownia seeds. Take 50-70 pills on an empty stomach with warm wine or plain water; suitable for patients requiring purgation.
Although low back pain belongs to the Kidney and Bladder, there are cases where the child disease affects the mother; thus, Liver injury from depression and anger also causes low back pain, treat with Tiaogan San (Regulate Liver Powder). There are cases where Earth disease affects Water; thus, Spleen injury from worry and overthinking also causes low back pain, treat with Chenxiang Jiangqi Tang (Agarwood Descend Qi Decoction) combined with Tiaoqi San (Regulate Qi Powder). Low back pain accompanied by sudden redness or blackness of the face indicates contention between Heart and Kidney, a difficult-to-treat syndrome.