1. بسم الله الرحمن الرحيم

2. Anatomy of the diaphragm

3. Origin of diaphragm 1- Sternal origin:
Back of xiphoid process of sternum.
2- Costal origin:
Inner aspect of lower 6 ribs.
3- Vertebral origin:
a. Two crura:
Right crus arises from the ventral aspect of the upper three lumbar vertebrae.
Left crus arises from the upper two lumbar vertebrae.

4. Origin of diaphragm
b. Arcuate ligaments: * Median arcuate ligament: A median tendinous arch connecting the right and left crura. * Medial arcuate ligament: On each side, connecting each crus with the tip of transverse process of L1. * Lateral arcuate ligament: On each side, connecting the tip of transverse process of L1 with the last rib.

5. Insertion of diaphragm
Into the central tendon of diaphragm which is formed of three lobes: 1- right lobe. 2- left lobe. 3- median lobe. * The central tendon is depressed and the lateral parts are elevated forming the right and left copula.

7. Nerve supply and action
Nerve supply: 1- Phrenic nerve: motor, sensory. 2- Lower intercostal nerves: sensory. Action: 1- Muscle of respiration. 2- Increase the intra abdominal pressure in forced actions. 3- right crus acts as a sphincter to the lower end of oesophagus.

8. Major openings in the diaphragm

9. Major openings in the diaphragm
1- IVC opening: a.Site: In the central tendon of diaphragm between right and median lobe. b.Level: T8 c.Structures passing through: 1)IVC. 2)Right phrenic nerve. 3)Lymphatics.

10. Major openings in the diaphragm
2- Aortic opening: a.Site: Posterior to median arcuate ligament. b.Level: T12 c.Structures passing through: 1)Aorta. 2)Azygos vein. 3)Thoracic duct.

11. Major openings in the diaphragm
3- Oesophageal opening: a.Site:Right crus. b.Level: T10 c.Structures passing through: 1)Oesophagus. 2)Vagi. 3)Anastomotic branches between left gastric and aortic oesophageal arteries.

12. Other structures passing through the diaphragm
1-Splanchnic nerves which pierce the crura. 2-Inferior hemiazygos vein which pierce the left crus. 3-Psoas major M. 4-Sympathetic trunk. *3,4 pass deep to the medial arcuate ligament. 5-Quadratus lumborum. 6- Subcostal N, Vs. *5,6 Pass deep to the lateral arcuate ligament.

13. Other structures passing through the diaphragm
7-Lower five intercostal Ns, Vs between the slips of the costal origin of diaphragm. 8-Superior epigastric vessels between sternal and costal origin. 9-Musculo phrenic vessels between the 7th and 8th costal slips.

14. Prof.: Dr. Wafaa Abdel-Rahman
Thank You
Prof.: Dr. Wafaa Abdel-Rahman