Intraabdominal pressure dilates the umbilical stalk within the ring.
The umbilical stalk is attached circumferentially to the underside of the umbilical skin. With a small defect, the hernia defect is usually filled with a wad of preperitoneal fat. Peritoneum may be pushed into the defect, creating a hernia sac. Abdominal contents may then enter the sac. All rights reserved.