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Diaphragmatic Hernia
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Origin
- Sternal Part
- small rigth and left slips arising from posterior surface xiphoid
process
- Costal part
- six slips arise from deep surfaces of lower six ribs and their costal
cartilages
- vertebral part
- crura
- right crus
- arises from sides of bodies of L1-L3
- some fibres pass to left around oesophagus
- left crus
- arises from sides of bodies of L1,L2
- arcuate ligaments
- medial
- thickened upper margin of fascia over psoas muscle
- from side of body of L2 to tip of transverse process L1
- lateral
- thickened upper margin of fasica over quadratus lumborum
- from transverse process L1 to lower border 12th rib
- median
- connects medial borders of both crura
- crosses anterior to aorta
Insertion
- central tendon
- superior surface partially fused with fibrous pericardium
Orifices
- vena cava at T8
- + terminal branches of right phrenic nerve
- oesophagus at T10 (through right crus)
- also with vagus nerves
- oseophageal branches of left gastric vessels
- lymphatics of lower 1/3 of oesophagus
- aorta at T12 (posterior to median arcuate ligament)
- also with azygos vein and thoracic duct
Other orifices
- greater, lesser and least splanchnic nerves pierce crura
- sympathetic trunks pass posterior to medial arcuate ligament
- superior epigastric vessels pass between sternal and costal origins
- left phrenic nerve peirces left dome
- neurovascular bundles of 7th to 11th intercostal spaces pass between
muscular slips of costal origin
Action
- on contraction central tendon pulled down
- increases vertical diameter of thorax
Nerve supply
- Phrenic nerve
- some sensory supply to periphery from lower 6 intercostal nerves
Functions
- inspiration
- abdominal straining
- weight-lifting
- thoraco-abdominal pump
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