Diaphragm

Three large openings

The aortic hiatus

The lowest and most posterior of the large apertures

level of the T 12

The esophageal hiatus

In muscular part of the diaphragm

At level of the T 10, and is elliptical in shape.

placed above, in front, and a little to the left of the aortic hiatus,

Transmits the esophagus, the vagus nerves, and some small esophageal arteries.

The vena caval foramen

the highest of the three,

situated about the level of the fibrocartilage between T 8 - T 9 vertebræ

quadrilateral in form

Transmits the inferior vena cava, some branches of the right phrenic nerve

lesser apertures,

two in the right crus : transmit the greater and lesser right splanchnic nerves;

three in the left crus : transmit the greater and lesser left splanchnic nerves and the hemiazygos vein

The gangliated trunks of the sympathetic usually enter the abdominal cavity behind the diaphragm, under the medial lumbocostal arches.

On either side two small intervals exist : diaphragm are deficient and are replaced by areolar tissue

One between the sternal and costal parts transmits the superior epigastric branch of the internal mammary artery

Other : not present in all, when exists separates the upper and back part of the kidney