It is located in its greater part in the stage known méso colic.
There is a small segment in the stage under méso colic
Descriptive anatomy of the duodenum
It is rolled up on him even by describing a loop more or less closed: the framework duodénal.
4 parts are distinguished to him:
The 1st duodenum: the higher duodenum
It is born following the pylore on the level from the right blank from the first lumbar vertebra (L1).
Its way is oblique in crânial and side right.
Its initial portion is mobile (exception).
The zone dilated after the pylore is the bulb duodénal which because of its histological configuration is the seat of frequent ulcer.
The 2nd duodenum: the downward duodenum
It follows upon the 1st duodenum by forming an angle of less 90°: the higher angle genu.
It goes down compared to the end from the transverse processes of L1 àL4.
It has as principal characteristics to receive the ways of drainage of pancreatic juice and the bile which comes from the foiepar the cholédoque conduit.
The 3rd duodenum: the horizontal duodenum
It follows upon the 2nd duodenum by forming an angle of 90°: the lower angle genu.
It has two characteristics:
- it is crossed by the vessels mesenteric superior ahead (arteries and veins). These vessels irrigate to it quasi totality of the remainder of the small intestine.
- it rests on L4 like a block.
If there is an important abdominal traumatism, the 3rd duodénal is crushed on L4 and there is risk of perforation.
The 4th duodenum: the ascending duodenum.
It is vertical, it extends from L4 to the end from the transverse process of L2.
On the level of L2, it continues with the remainder of the small intestine: jejunum.
The transitions is done by a very acute angle: the duodéno-jejunal angle which comprises a muscle attaching it to the left pillar of the diaphragm: it is the muscle hanger of the duodéno-jejunal angle.
The spleen is a large blood-vascular 
The liver is the largest gland of the human body.It has the shape of a flattened ellipsoid, passes almost transversely