There are currently two theories about the occurrence of rectal prolapse. One is the sliding hernia theory: rectal prolapse is considered to be a sliding hernia of the rectal pelvic concave peritoneum. Under the pressure of the abdominal viscera, the pelvic concave peritoneal fold wall gradually sags, pressing the anterior wall of the rectum covering the peritoneal part. The rectum ampulla, and finally prolapsed through the anus. The second is the intussusception theory: normally the upper end of the rectum is fixed near the sacral promontory. Due to chronic cough and constipation, the increase in intra-abdominal pressure causes this fixed point to be injured, and it is easy for intussusception to occur at the junction of the sigmoid colon and rectum. Under the continuous effect of increased pressure and other factors, the intestinal canal inserted into the rectum gradually increases. Due to the alternating intussusception and intussusception, the rectal ligament and levator ani muscles are injured, and the intussusception is gradually increased. . Some people think that the above two theories are the same thing, but they are only different in degree. Sliding hernia is also an intussusception, but it does not affect the entire circle of intestinal wall. The latter is full-layer nesting. Infants and children with indigestion, cold or intestinal infections can cause diarrhea, which is a frequent pathological phenomenon. Due to the incomplete development of the anorectal tissue in children, the curvature of the sacrum has not yet formed, and the rectum is vertical, almost in line with the anal canal, and the posterior wall loses the strong support of the sacrum. If the diarrhea does not heal for a long time or recurs repeatedly, it can cause the rectum to separate from the surrounding tissue, the supporting tissue around the rectum relaxes, and cannot be astringent. Therefore, when diarrhea occurs in children, it should be treated in time.