What is the mesentery?
The mesentery is also referred to as mesentery or meso and is a doubling of the peritoneum, the peritoneum. It has the function of a "hanging tape" of the intestine and emanates from the posterior abdominal wall. The intestine is partially attached to the mesentery, allowing for fixation with simultaneous mobility.
In a broader sense, the term mesentery refers to all mesenteries of the organs within the peritoneum. In a narrower definition, the mesentery refers only to the mesentery of the small intestine, more specifically the ileum and the jejunum.
Anatomy & Construction
The respective intestinal sections are partially hung on the mesenteries, which ensures that they remain mobile despite a certain fixation. To supply the intestine, the mesenteries contain lymphatic channels, connective and fatty tissue, nerves and vessels.
The mesentery passes over the intestinal loops into the serosa of the intestine. Organ-remote mesenteric attachments are called "mesentery roots" (radix mesenterii). At the radix mesenterii, the visceral and parietal sheets of the peritoneum meet. A mesentery spanned between two organs is called a ligament.
There are several mesenteries in the human body, some of which exist only in the embryonic stage and later regress. The mesenteries can be divided into:
The mesogastrium consists of two parts, the mesogastrium ventral and the mesogastrium dorsale. The mesogastrium ventrale is the anterior mesentery of the stomach, the mesogastrium ventrale the posterior. The mesogastrium develops during the embryonic period and changes in the development of the body into various other structures.
The mesogastrium ventrale, which exists during the embryonic stage, can be subdivided into the ventral and the dorsal mesohepaticum. The Mesohepaticum ventrale develops into the ligament falciforme hepatis. The mesohepaticum dorsale develops into the omentum minus.
The mesogastrium dorsale, the posterior mesentery of the stomach, develops into the greater omentum as well as the gastric ligament, the gastro-intestinal ligament, the gastrophenic ligament, the phrenic ulnar ligament and the phrenicocolic ligament.
The mesoduodenum is the mesentery of the duodenum. It develops during the embryonic period. It is subdivided into the mesoduodenum dorsale (the posterior mesoduodenum) and the mesoduodenum ventrale (the anterior mesoduodenum).
In the mesoduodenum dorsale, the attachment of the pancreas (pancreas) develops. After the embyrional stage it engulfs with the backward displacement of the duodenum with the posterior abdominal wall.
The mesoduodenum ventrale together with the mesogastrium ventrale becomes the omentum minus, which can be subdivided into the ligamentum hepatogastricum and the ligamentum hepatoduodenale.
The mesojejunum is the mesentery of the jejunum. It is attached to the posterior abdominal wall together with the mesoileum. In the mesojejunum, the jejunal and jejunal veins run from the superior mesenteric artery or from the superior mesenteric vein, as well as nerve fibers and lymphatics, which supply the small intestine.
The mesoileum is the mesentery of the ileum. It is attached to the posterior abdominal wall together with the jejunal mesentery (mesojejunum). The attachment site is called radix mesenterii. In the mesoileum, the ileal arteries and the ileal arteries extend from the superior mesenteric artery or from the superior mesenteric vein, as well as nerve fibers and lymphatics, which supply the ileum.
The mesorectum is the mesentery of the rectum (rectum). It connects the rectum with the sacrum (sacrum).
Furthermore, the mesocolon exists, which can be subdivided into:
- Mesocolon transversum
The mesocolon transversum is the mesentery of the transverse colon, the middle part of the colon. It forms together with the ligamentum gastrocolicum the recess inferior of the bursa omentalis.
- Mesocolon sigmoideum
The mesocolon sigmoideum is the mesentery of the sigmoid colon (sigmoid). It forms the recessus intersigmoideus above the left psoas major muscle. It is very flexible overall, but is fixed at the transition points to the rectum and the descending colon.
The mesoappendix is the mesentery of the appendix vermiformis, the appendix. The mesoappendix represents a peritoneal duplication and may extend to the tip of the appendix. It connects the appendix with the ileum. It also contains the appendicular artery, the appendicular vein, as well as the lymphatic vessels and nerves.
Function & Tasks
The mesentery as a generic term stands for a "mesentery", which forms the hanging band of the intestine. It guarantees the fixation of the intestine with simultaneous mobility. The other functions of the various mesenteries can be briefly summarized by the fact that they pass through nerves, lymphatics and vessels, whereby the respective organs are supplied. In particular, the exact function and function of the mesentery is related to the organ being supplied.
In connection with the mesentery, a so-called volvulus, a rotation of a section of the digestive tract about its mesenteric axis, is conceivable as a possible complaint or illness. This rotation restricts the blood supply to the affected segment passing through the mesentery. Possible intestinal obstruction and the loss of intestinal tissue (intestinal gangrene). The acute Volvulus represents a surgical emergency.
Furthermore, anatomical malformations of the mesenteries and injury of the mesenteries by external influence, eg by shooting or stab wounds are possible.