Anatomy question. mesenteries and peritoneum.?

When the spleen ruptures, the blood goes into the peritoneal cavity. If you have a hole in the anterior wall of the stomach, the contents would leak into the peritoneal cavity. A hole in the posterior wall of the stomach leads to the lesser sac. The greater omentum can't really rupture. There are blood vessels in it, and if they bleed, they do so into the peritoneal cavity or within the greater omentum itself. If the small intestine ruptures, it usually does so into the peritoneal cavity. It is also possible for it to have a contained rupture into the mesentery. The duodenum (which is the first part of the small intestine) will generally leak into the retroperitoneum or the lesser sac. A urethral injury just goes into soft tissue in the pelvis. The urethra is the tube that empties your bladder. When you get to the urethra, you are pretty much completely outside of the abdominal cavity.