[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Embryology](https://durgical.com/en/embryology/) › [Digestive system](https://durgical.com/en/embryology/#a-digestive) › Mesenteries, the omental bursa and the spleen [Embryology](https://durgical.com/en/embryology/) · [Digestive system](https://durgical.com/en/embryology/#a-digestive) # Mesenteries, the omental bursa and the spleen - Embryonic structure The peritoneal sheets that hang the gut fold as the organs turn, forming the omenta and the omental bursa; the spleen grows between them. Updated 2026-11-01 **See it in 3D:** [Greater omentum](https://durgical.com/en/anatomy/greater-omentum/) · [Lesser omentum](https://durgical.com/en/anatomy/lesser-omentum/) · [Mesocolon](https://durgical.com/en/anatomy/mesocolon/) · [Spleen](https://durgical.com/en/anatomy/spleen/) · [Falciform ligament](https://durgical.com/en/anatomy/falciform-ligament/) · [Splenic artery](https://durgical.com/en/anatomy/splenic-artery/) · [Peritoneum](https://durgical.com/en/anatomy/peritoneum/) ## Key points - Dorsal mesogastrium → greater omentum and the gastrosplenic and splenorenal ligaments; the spleen forms between its layers. - Ventral mesogastrium → lesser omentum (hepatogastric and hepatoduodenal ligaments) and falciform ligament. - The hepatoduodenal ligament carries the portal triad: bile duct, proper hepatic artery and portal vein. - The omental bursa lies behind the stomach and communicates with the greater sac through the omental (epiploic) foramen of Winslow. - Week 5: the spleen arises from mesenchyme between the layers of the dorsal mesogastrium; it is mesodermal, not endodermal. - Secondarily retroperitoneal: duodenum (except the bulb), pancreas, ascending colon and descending colon. ## What it is The primitive gut hangs from the posterior wall by a dorsal mesentery; only the end of the foregut also has a ventral mesentery, derived from the septum transversum. As the stomach rotates, the dorsal mesogastrium forms the greater omentum and the omental bursa, and the spleen develops between its layers. Some mesenteries fuse with the posterior wall and leave organs secondarily retroperitoneal. ## Key facts - Weeks 5–6: the splenic primordium appears in the dorsal mesogastrium. - The fetal spleen takes part in haematopoiesis. - The splenic artery is a branch of the celiac trunk, although the spleen does not come from the gut. ## Structure - Dorsal mesentery: suspends the tube from the lower esophagus to the cloaca and carries its vessels, nerves and lymphatics. - Ventral mesentery: present only at the terminal esophagus, stomach and proximal duodenum; it comes from the septum transversum. - The liver grows into the ventral mesentery and divides it into the lesser omentum, toward the stomach, and the falciform ligament, toward the anterior wall. ## What it becomes - Greater omentum: a fold of dorsal mesogastrium hanging in front of the intestines; its layers fuse and attach to the transverse colon. - Omental bursa (lesser sac) and omental foramen. - Mesentery of the small intestine, transverse mesocolon and sigmoid mesocolon, which persist. - Spleen with its gastrosplenic and splenorenal ligaments. ## Clinical notes - Accessory spleens: nodules of splenic tissue, mostly near the hilum; they can explain relapse of a haematological disease after splenectomy. - Polysplenia and asplenia: linked to laterality defects (heterotaxy) and congenital heart disease. - Abnormal mesenteric fixation: a narrow mesenteric base in malrotation, with a risk of volvulus. - Internal hernias through the omental foramen or mesenteric defects. ## Memory aid The dorsal mesogastrium is a curtain the stomach drags along as it turns: it drops like an apron (greater omentum), leaves a pocket behind (lesser sac) and hides the spleen in its folds. ## Test yourself Think of the answer, then tap the question to see it. ## Which mesentery gives rise to the greater omentum? The dorsal mesogastrium, which the rotating stomach pulls along and which grows into an apron. ## What does the hepatoduodenal ligament contain? The portal triad: bile duct, proper hepatic artery and portal vein; it forms the anterior edge of the omental foramen. ## Is the spleen a foregut derivative? No. It is mesodermal, arising from mesenchyme of the dorsal mesogastrium, although it is supplied by a branch of the celiac trunk. ## Why is the pancreas secondarily retroperitoneal? Because the dorsal mesentery of the duodenum, which contained it, fuses with the peritoneum of the posterior wall. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/embryology/mesenteries-the-omental-bursa-and-the-spleen/) ## See it in 3D The structures of Durgical's 3D anatomy where it is found. - [Greater omentum](https://durgical.com/en/anatomy/greater-omentum/) - [Lesser omentum](https://durgical.com/en/anatomy/lesser-omentum/) - [Mesocolon](https://durgical.com/en/anatomy/mesocolon/) - [Spleen](https://durgical.com/en/anatomy/spleen/) - [Falciform ligament](https://durgical.com/en/anatomy/falciform-ligament/) - [Splenic artery](https://durgical.com/en/anatomy/splenic-artery/) - [Peritoneum](https://durgical.com/en/anatomy/peritoneum/) ## Related - [Primitive gut: foregut, midgut and hindgut and their arteries](https://durgical.com/en/embryology/primitive-gut-foregut-midgut-and-hindgut-and-their-arteries/) - [Foregut: esophagus, stomach rotation and duodenum](https://durgical.com/en/embryology/foregut-esophagus-stomach-rotation-and-duodenum/) - [Liver, gallbladder and pancreas](https://durgical.com/en/embryology/liver-gallbladder-and-pancreas/) - [Midgut: physiological herniation and rotation](https://durgical.com/en/embryology/midgut-physiological-herniation-and-rotation/) - [Intraembryonic coelom: pericardial, pleural and peritoneal cavities](https://durgical.com/en/embryology/intraembryonic-coelom-pericardial-pleural-and-peritoneal-cavities/) - [Malrotation and midgut volvulus](https://durgical.com/en/embryology/malrotation-and-midgut-volvulus/) - [Biliary atresia](https://durgical.com/en/embryology/biliary-atresia/) ## Related conditions - [Splenic injury](https://durgical.com/en/conditions/splenic-injury/) [← All of embryology](https://durgical.com/en/embryology/) Educational content on embryonic development; not a guide to prenatal diagnosis or to medicines in pregnancy and no substitute for a health professional's advice. No doses are given. Sources: [Anatomy, Abdomen and Pelvis, Peritoneum](https://www.ncbi.nlm.nih.gov/books/NBK534788/) (StatPearls Publishing (NCBI Bookshelf), 2023); [Anatomy, Abdomen and Pelvis, Spleen](https://www.ncbi.nlm.nih.gov/books/NBK482235/) (StatPearls Publishing (NCBI Bookshelf), 2026); Langman's Medical Embryology, 13th ed., ch. 15: Digestive System (Wolters Kluwer, 2015). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/embryology/mesenteries-the-omental-bursa-and-the-spleen/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/embryology/mesenteries-the-omental-bursa-and-the-spleen/