Module 01 - Thoracic Region Flashcards
(161 cards)
What is a septum?
A wall or partition dividing a body space of cavity each named according to its location
Describe the diaphragm structurally
Thin musculotendinous septum that separates the thoracic and abdominal cavities
Its structure comprises 2 domes; left and rise, a central tendon, and crus
What is the principal muscle of respiration?
Diaphragm
What do respirologists call the domes of the diaphragm?
right and left hemidiaphragm
How many domes does the diaphragm have? + what are they called
2
Right dome
Left dome
How high can the right dome rise?
Upper border of the fifth rib
How high can the left dome rise?
Lower border of the fifth rib
Where do the peripheral muscular fibers of the diaphragm attach?
Central Tendon
Where is the Central Tendon located?
Just inferior to the fibrous pericardium of the heart
What is the right crus?
muscuolotendinous extension of the diaphragm that originates from the front of the bodies of the upper THREE lumbar vertebrae - on the right side
What is the left crus
muscuolotendinous extension of the diaphragm that originates from the front of the bodies of the upper TWO lumbar vertebrae - on the left side
Name two differences between right and left crus
Right crus is on the RIGHT anterior side of the Upper 3 lumbar vertebrae
Left crus is on the LEFT anterior side of the upper 2 lumbar vertebrae
How many apertures are there in the diaphragm? What are they
3
Caval Opening
Esophageal Hiatus
Aortic Hiatus
What is an aperture?
an opening that allow passage of key structure
Where is the Caval Opening?
At the level of the 8th thoracic vertebra, in the posterior thorax on the right side
What structure passes through the caval opening?
Inferior Vena Cava (IVC)
What is the esophageal hiatus?
It is an aperture (opening) in the the diaphragm that allows the passage of the esophagus through the diaphragm
Where is the esophageal hiatus?
In the muscle of the right crus, at the level of the 10th thoracic vertebra
Where does the esophagus lie in its thoracic portion
As it descends through the thorax it deviates left, lying anterior to the thoracic aorta
Where is the aortic hiatus?
between right and left crus, anterior to the 12th thoracic vertebra - it is on the left side of the posterior thorax
What’s the mnemonic to remember all three apertures of the diaphragm?
I ate 10 eggs at 12
IVC T8 T10 Esophagus Aorta T12
What direction do the fibres of external intercostals run?
Anteroinferiorly from the lower border of the rib.
“Hand in your pockets” - runs same direction as your hand if you were to put them in your pockets
What direction do the fibres of internal intercostals run?
Posterosuperiorly from the upper border of the rib
What direction do the fibres of innermost intercostals run?
Posterosuperiorly from the upper border of the rib