Constipation refers to various causes of difficult defecation, reduced frequency of defecation, or a sense of incomplete defecation, and can be divided into two categories: functional constipation and secondary constipation. Functional constipation typology: 1, slow transmission type (STC): also known as delayed emptying type or colonic weakness, refers to the speed of intestinal contents from the proximal colon to the distal colon and rectum movement is lower than normal, associated with abnormal intestinal dynamics. Manometry studies have shown a significant reduction in the amplitude frequency of colonic contractions and propulsive peristalsis, mostly associated with abnormalities in the interosseous plexus and alterations in enteric neurotransmitters, the mechanisms of which include: A reduction in the number of high-amplitude propulsive contractions of the colon that drive the movement of intestinal contents to the distal end, possibly associated with a reduction in vasoactive intestinal peptide (VIP) receptors, elevated levels of growth inhibitory hormone (SS), and genes related to 5-HT, gastrin, calcitonin peptide (CGRP), substance P (SP), nitric oxide (NO), and other gastrointestinal hormone levels. The main clinical manifestations are lack of bowel movement or hard feces, delayed passage time of the whole stomach or colon or low colonic power. 2, export obstruction type (OOC): also known as pelvic floor dysfunction, refers to the accumulation of feces in the rectum can not be smoothly expelled from the anus, commonly in the elderly and women, OOC is a group of multi-source dysfunction, rectal sensory hypofunction, anorectal reflex weakening, contradictory contraction of the anal canal sphincter during defecation, pelvic floor dynamics disorders so that the anal canal pressure exceeds the rectal pressure are the basis for the development of export obstruction type constipation. Clinically, it is characterized by a feeling of incomplete defecation, straining to defecate or low defecation volume, and often accompanied by a feeling of anorectal cramping. There is often anal sphincter dysfunction, pelvic floor muscle dysfunction, etc. 3, mixed type: slow transmission and functional outlet obstruction exist at the same time. Functional constipation examination methods: 1, colonic transit time (CTT): swallow capsules containing impermeable X-ray markers, and take abdominal plain films at 24h, 48h and 72h (if necessary) to calculate the excretion rate. The excretion rate at 72h is >90% under normal conditions. The location of the marker in the colon was determined from the bony marker in the abdominal plain film. On the right side of the spine, the marker in the area above the line between the fifth lumbar vertebra and the pelvic outlet was located in the right hemicolon. On the left side of the spine, markers above the line between the fifth lumbar vertebra and the left anterior superior iliac spine are located in the left hemicolectum; markers below the above line are located in the sigmoid rectum. If most of the markers remain above the sigmoid colon, it is the slow transmission type, and if it is located in the sigmoid rectum, it is the exit obstruction type. 2.Defecography (BD): The photographs taken were compared with force discharge and sedation to observe the changes in resting pressure, anal retraction and anorectal angle during force discharge, to assess the contraction and relaxation function of the puborectal muscle and to understand the anatomical abnormalities of the rectal pelvic floor. The perineal descent with forceful evacuation with supra-anal distance ≥ 31 mm and pelvic floor spasm syndrome are the contraction of pelvic floor muscles without relaxation during forceful evacuation, and the anorectal angle does not increase during forceful evacuation and more spastic pressure marks of the puborectal muscles appear. 3.Anorectal manometry (ARM): measured by perfusion or balloon method to determine the function of the internal and external anal sphincter.