According to the location of intestinal entrapment and the presence of obvious organic lesions, it is divided into primary intestinal entrapment and secondary intestinal entrapment, secondary intestinal entrapment is mostly seen in tumors, trauma and post-surgery and inflammatory lesions of the intestine.
Primary (30%): the occurrence of intestinal segment and its vicinity can not find obvious organic factors, accounting for 75% to 90% of the number of pediatric intussusception, only 10% to 15% of adults for primary, infants and children intussusception onset of age below 1 year, 5 to 9 months of the highest incidence of breastfeeding children, more than 2 years of age gradually decreased, mostly in the season of climate change, especially in the spring and autumn, this season In addition, sudden changes in the nature of food, food allergies, diarrhea, etc. in infants and young children may become a contributing factor to intussusception, the neonatal ileocecal tract is often not fixed, usually only in the postnatal years gradually fixed attached to the posterior abdominal wall; because the tract is too long, flaccid, resulting in excessive ileocecal wandering, is the main cause of the This is the main anatomical factor in the development of intussusception in this area.
Tumor (25%): It is the most common cause of adult intestinal loop, polyps, smooth muscle tumor, lipoma, fibroma and cancer of the intestine can cause secondary intestinal loop, because the presence of tumor in the ileocecal region or other intestinal segments often leads to intestinal peristalsis malfunction, and becomes a trigger point for loop. Nagomey statistics, 2/3 of the colon and 1/3 of the small intestine are cancerous, the latter 70% are metastatic cancer, small intestine is covered by choroidal adenoma, lipoma, smooth muscle tumor and various polyps including Orenstein reported a case of duodenojejunostomy complicated by pancreatitis due to choriocapillaris adenoma, and Jennings reported a case of duodenojejunostomy due to lipoma.
Trauma and surgery (20%): abdominal trauma and intussusception after surgery is increasingly reported, Duncan due to abdominal trauma dissection in 586 cases, 21 cases of postoperative intestinal obstruction, of which 6 cases (28.6%) for intussusception, it is worth noting that these 6 cases originally no small intestine injury, but more with shock and liver injury, Xianyang City Second Hospital has admitted a case of multiple small intestine due to sharp objects Cooperman reported that post-appendectomy stump overlap occurred mostly in 2 weeks after surgery, and there were also cases with symptoms up to 6 years after surgery. It is not clear why intestinal stenosis occurs after trauma or abdominal surgery, but it is assumed that it may be related to intestinal wall hematoma, edema, adhesions, intestinal dysfunction, electrolyte imbalance, intestinal cavity built-in tube and chronic intestinal dilatation, and poor intestinal anastomosis alignment.
Other causes (10%): intestinal inflammation causes intestinal peristalsis, mainly limited ileitis, nonspecific ileocecal ulcers, acute ileocecal flap, acute and chronic appendicitis, etc. In addition, intestinal tuberculosis, bacillary or typhoid ulcers can cause intussusception. The hematoma is a rare cause of secondary intussusception.