Duodenojejunal flexure

Structure

The ascending portion of the duodenum ascends on the left side of the aorta, as far as the level of the upper border of the second lumbar vertebra. At this point, it turns abruptly forward to merge with the jejunum, forming the duodenojejunal flexure. This forms the beginning of the jejunum. The duodenojejunal flexure is surrounded by the suspensory muscle of the duodenum. It is retroperitoneal, so is less mobile than the jejunum that comes after it, helping to stabilise the jejunum.

The duodenojejunal flexure lies in front of the left psoas major muscle, the left renal artery, and the left renal vein. It is covered in front, and partly at the sides, by peritoneum continuous with the left portion of the mesentery.

Clinical significance

The ligament of Treitz, a peritoneal fold, from the right crus of diaphragm, is an identification point for the duodenojejunal flexure during abdominal surgery.

Additional images

File:Gray1042.png|Duodenojejunal fossa. File:Gray1225.png|Front of abdomen, showing surface markings for duodenum, pancreas, and kidneys.

References

References

1. 10.1007/s13304-020-00910-7
2. Lissauer et.al. [https://books.google.com/books?id=gQbQDwAAQBAJ ''Neonatology at a Glance'']. John Wiley & Sons, 2020, p.125.
3. (2017-01-01). "Small Intestine". Elsevier.
4. Drake, Richard L.. (2005). "Gray's anatomy for students". Elsevier/Churchill Livingstone.
5. (2017-01-01). "Chapter 2 - Anatomy, Physiology, and Selected Pathologies of the Gastrointestinal Tract". Academic Press.
6. Jacob, S. (2007) Chapter 4: Abdomen; Human anatomy, A clinically-orientated approach.