Causes for Small Intestinal Obstruction
Disease	Description
Adhesions	A loop of bowel can get caught in an "internal" hernia produced by a band of connective tissue between other loops of bowel or peritoneum. There is typically a history of previous surgery.
Hernia	An inguinal hernia can be large enough to trap a loop of bowel that slips into the hernia sac.
Neoplasm	Primary carcinomas of the small bowel are rare, but metastases are not, and there are plenty of nearby primary sites--colon, ovary, pancreas, stomach, etc.
Volvulus	Small bowel can twist on the mesentery to create a volvulus and an obstruction. This condition is rare
Intussusception	The small bowel can telescope on itself, producing an obstruction. This condition is rare.
Stricture	Inflammation can narrow the lumen. Crohn disease is most likely to do this. Tuberculous enteritis is rare. Foreign bodies may perforate or produce local irritation that constricts the lumen.

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