First, the concept of constipation Constipation is a symptom of a variety of diseases, manifested as too little stool, too hard, too difficult to discharge, or combined with some special symptoms: such as prolonged straining to defecate, rectal distension, incomplete defecation, or even the need to use manipulation to help defecate. Without the use of laxatives, the spontaneous evacuation of feces is not more than 2 times in 7 d or there is no bowel movement for a long time. Second, the etiology of constipation normal defecation needs to contain a certain amount of dietary fiber gastrointestinal contents at a normal speed through the digestive tract segments, timely arrival in the rectum, and can stimulate the rectal anal canal, triggering defecation reflex. During defecation, the pelvic floor muscle groups coordinate their activities to complete defecation. Any one of the above obstacles can cause constipation. 1, general etiology: (1) unreasonable diet, dietary fiber intake is a common cause; (2) poor defecation habits; (3) long-term inhibition of the urge to defecate; (4) irrational use of laxatives; (5) environmental or defecation position changes; (6) pregnancy; (7) old age, nutritional disorders. 2, colorectal and pelvic floor organic lesions and functional disorders: (1) colonic mechanical obstruction: benign and malignant tumors; (2) rectal or anal canal outlet obstruction: anal fissure, anal canal or rectal stenosis, internal sphincter dystocia, anterior rectal protrusion, rectal prolapse, pelvic floor spasticity syndrome, puborectalis hypertrophy, sacral rectal separation, pelvic floor hernia, etc.; (3) colorectal neuropathic and muscular abnormality: pseudoenteric obstruction, congenital megacolon, idiopathic megacolon, megarectum, slow-passing type i.e. transmissible colonic bradykinesia, irritable bowel syndrome (constipation type), etc. 3, colorectal nerve abnormalities: (1) central: various brain disorders, mass compression, spinal cord lesions, multiple sclerosis, etc.; (2) innervation abnormalities. 4.Mental or psychological disorders: (1) psychosis; (2) depression; (3) anorexia nervosa. 5.Medicinal origin: (1) Drugs: such as codeine, morphine, antidepressants, anticholinergic agents, iron, calcium channel antagonists, etc.; (2) Braking. 6.Endocrine abnormalities and metabolic diseases: such as hypothyroidism, hyperparathyroidism, hypokalemia, diabetes mellitus, hypopituitarism, pheochromocytoma, and lead poisoning. 7, connective tissue diseases: such as scleroderma. Third, the constipation examination methods and assessment of constipation for the special examination of constipation, should be in the detailed history and a variety of routine checks such as anorectal auscultation, barium enema and colonoscopy, except for organic pathology after the selection. 1, ask the medical history: detailed inquiry about the symptoms of constipation and the course of the disease, dietary habits, gastrointestinal symptoms, accompanying symptoms and diseases, and the use of medication; constipation symptom characteristics (frequency of bowel movements, stool, whether it is difficult or not, whether there is a lack of stool after the bowel movement, a feeling of falling and fecal material); assessment of the mental, psychological state; attention to the presence of tumor warning symptoms, such as blood in the stool, anemia, emaciation, fever, black stools, abdominal pain, and so on. 2, general examination: anorectal fingerprinting can understand whether there is fecal retention in the rectum and the nature of the anal canal, rectal stenosis and rectal occupancy, etc., and can understand the anal canal sphincter, the functional status of puborectalis muscle and whether there is rectal protrusion, rectal prolapse, etc.; routine blood, fecal routines, fecal occult blood test is to exclude the colorectal and anal organisms, an important and simple examination; biochemical examination, hormone level and metabolic examination, if necessary, Hormone level and metabolism examination; for suspected anal and colorectal lesions, anoscopy, colonoscopy or barium enema should be performed. 3.Special examination: For patients with long-term chronic constipation, the following examinations can be chosen as appropriate. Gastrointestinal transit test (GIT): commonly used impermeable X-ray markers. Laxatives and other drugs affecting intestinal function are prohibited from 3 d before the test. Twenty markers are swallowed with the test meal at breakfast, and one X-ray film of the abdomen is taken at certain intervals (6, 24, 48, 72 h after taking the markers) to calculate the rate of elimination. Under normal circumstances, most of the markers were excreted after 48-72 h of marker administration. According to the distribution of markers on the radiograph, it is helpful to assess whether the constipation is slow transit constipation (STC) or outletobstructive constipation (OOC), which is easy to perform and still commonly used. Defecography: The feces should be emptied before imaging. Thick barium with appropriate amount of sodium carboxymethylcellulose or barium paste 300 ml enema to fill up to the descending colon, and apply the anal canal to mark the anus. Photograph the mucosal phase after resting, anal lifting, forceful evacuation, and expulsion of the contrast agent while seated sideways on a special fecal bucket. The film should include the sacrococcyx, pubic symphysis, and anus. Measurements: In normal subjects, the anus angle is taken as the posterior anus angle, which increases with force from rest and should be greater than 90 degrees, and is minimized with anal lifting. The supraanal distance, pubic distance, and pubic distance are measured at the pubic caudal line, with negative values above the pubic caudal line and positive values below. The supra-anal distance is greater than the resting distance, but the supra-anal distance must be less than 30 mm (less than 35 mm in menstruating women), and the ethano- pubic distance and mini-pubic distance are negative values. Sacrorectal distance measures the distance between the sacrococcygeal joints from sacral 2 to 4, between the sacrococcygeal joints, and between the tip of the coccyx and the posterior end of the rectum in five positions, and the sacrorectal distance should be less than 10 mm or less than 20 mm and homogeneous. Anterior rectal dilatation is a pouch-like protrusion of the distal portion of the jugular abdomen into the anterior aspect, with a depth of less than 15 mm. barium is discharged smoothly. Fecography is useful in the diagnosis of anatomic and dysfunctional abnormalities of the rectum and anal canal. If necessary, fecography can be synchronized with pelvic floor peritoneography to help diagnose pelvic floor hernia and endorectal intussusception. Anorectal manometry: there are liquid, gas, sensorimeter manometry, commonly used perfusion or liquid manometry, the indicators include rectal pressure, anal tube resting pressure and anal tube systolic pressure and anorectal inhibitory reflexes, but also determine the rectal sensory function and rectal compliance. It helps to assess the anal sphincter, rectum with or without power and sensory dysfunction. Pelvic floor, pelvic electromyography: commonly used electrodes are concentric needle electrode and anal plug electrode. Recording the wave amplitude and action potential of anal canal electromyography can determine the presence or absence of myogenic lesions; pubic nerve latency determination can show whether there is any damage to the pubic nerve. Colonic pressure monitoring: a pressure transducer is placed into the colon and changes in colonic pressure are monitored continuously for 24 to 48 h under relatively physiologic conditions to determine the presence or absence of colonic weakness. It is important in guiding the choice of surgical treatment, especially segmental colectomy, for constipation. Other: anal ultrasound endoscopy can understand the anal sphincter with or without defects or functional abnormalities; pelvic floor dynamic magnetic resonance imaging can be used to accurately evaluate pelvic organ prolapse and pelvic floor morphology. The diagnosis of constipation should include: the cause and/or trigger of constipation, the degree and type of constipation. It is important to understand the extent of the involvement of constipation, the presence of local structural abnormalities and the causal relationship with constipation, which is essential for the development of treatment and the prediction of outcome. 1, the degree of constipation: mild: symptoms are mild, does not affect life, can get better after general treatment, no need to use drugs or less use of drugs; severe: constipation symptoms persist, the patient is unusually painful, serious impact on life, can not stop drugs or treatment is ineffective; moderate: is between the two. The so-called intractable constipation is often severe constipation, which can be seen in the exit obstruction type constipation, colon weakness and severe constipation type irritable bowel syndrome (IBS). Types of constipation: According to the clinical symptoms of constipation, it can be divided into two basic types: slow transmission type (STC) and outlet obstruction type (OOC); OOC is more common, and many patients complaining of constipation have rectal emptying abnormalities, and the simultaneous existence of STC and OOC is a mixed type. The constipation type of irritable bowel syndrome is a type of constipation related to abdominal pain or bloating, and at the same time, it may also have the characteristics of the above types. V. Treatment of constipation Treatment principle: According to the mild, medium and severe degree of constipation and the etiology and type of constipation, individualized comprehensive treatment is adopted to restore normal defecation.