Anatomy of the thorax

Question 1

What does the thorax contain?

Answer 1

Lungs
heart
oesophagus
trachea
major vessels e.g. aorta

Question 2

What is the thoracic wall made up of?

Answer 2

12 pairs of ribs
costal cartilages
sternum
nerves and arteries that supply it 
intercostal muscles 
thoracic vertebrae

Question 3

What is the sternum made up of?

Answer 3

Manubrium
Body
Xiphoid process

Question 4

What are the true ribs?

Answer 4

Ribs 1-7

Their cartilage is directly attached to the sternum

Question 5

what are the false ribs?

Answer 5

ribs 8-10

their cartilage attaches to the cartilage above, rather than directly to the sternum

Question 6

what are the floating ribs?

Answer 6

ribs 11 and 12

they don’t attach to the sternum at all

Question 7

What is the superior thoracic aperture?

Answer 7

region just above the first rib, it is a thoracic opening.

Question 8

What does inferior thoracic aperture do?

Answer 8

it connects the thorax with the abdomen

Question 9

what attaches at the inferior thoracic aperture?

Answer 9

diaphragm

Question 10

what is the diaphragm, what is is the principal muscle for and where does it project upto?

Answer 10

a dome shaped, sheet of muscle which is the principal muscle of respiration. it extends up to the level of the 5th rib

Question 11

What are the attachments of the diaphragm?

Answer 11

Attachments:
• Inferior 6 costal cartilages and adjacent ribs
• Xiphoid process
• L1-L3 vertebrae (extends down to attach to top 3 lumbar vertebrae)

Question 12

What is the nerve supply of the diaphragm

Answer 12

Nerve supply:
• Phrenic nerve (C3-C5)

C3,4 ,5 – Keep the diaphragm alive !!!

Question 13

what is an aperture?

Answer 13

an opening to allow vessels to pass through

Question 14

What are three diaphragmatic apertures?

Answer 14

Caval opening (IVC)
Oesophageal hiatus
Aortic hiatus

Question 15

What drains through each diaphragmatic aperture and at what level

Answer 15

Caval: IVC at T8
Oesophagus: Oesophagus at T10
Aortic: Aorta at T12

I 8 10 E (American spelling) A 12!!!

Question 16

List the apertures form anterior to posterior

Answer 16

Caval/IVC (MOST ANTERIOR)
oesophagus
aorta

Question 17

What are the 3 intercostal muscle layers?

Answer 17

Three layers: external, internal, innermost

Question 18

what direction do external muscle fibres run in? What direction do they pull on the ribs?

Answer 18

They run from outwards to inwards and downwards. They lift the ribs below it. (inspiration)

Question 19

what direction do internal muscle fibres run in? What direction do they pull on the ribs?

Answer 19

they run downwards and outwards. they pull the above rib downwards.

Question 20

Where is the innermost muscle layer?

Answer 20

Deep to the inner muscle layer, it forms an incomplete layer

Question 21

Where does the neurovascular bindle lie?

Answer 21

between the internal and innermost layers

Question 22

what are the primary muscles of inhalation?

Answer 22

diaphragm

external intercostal

Question 23

what are the accessory muscles of inhalation for when it is active? (4)

Answer 23

sternocleidomastoid
pectoralis minor
scalene
serratus anterior

Question 24

what are the accessory muscles of exhalation for when it is active? (5)

Answer 24

internal oblique
external oblique 
rectus abdominus
transversus thoracis
internal intercostal

Question 25

From superior to inferior what is the order of the NV bundle? What is most exposed/least protected?

Answer 25

Vein
Artery
Nerve
(VAN)

The nerve is most exposed.

Question 26

What does the Posterior intercostal artery originate from ?

Answer 26

Aorta

Question 27

What does the Anterior intercostal artery originate from ?

Answer 27

Internal thoracic artery

Question 28

Where does the internal thoracic artery run?

Answer 28

On either side of the sternum

Question 29

Where does the internal thoracic artery originate from?

Answer 29

subclavian artery

Question 30

What does internal thoracic artery bifurcate into?

Answer 30

Superior epigastric

musculophrenic artery

Question 31

if the proximal aorta is restricted how can blood flow be maintained.

Answer 31

Subclavian – internal thoracic – anterior intercostal - posterior intercostal – aorta

Question 32

What are the divisions of the thoracic cavity?

Answer 32

Left and right pulmonary cavity

mediastinum

Question 33

What is the main organ in the mediastinum?

What are some of the other organs?

Answer 33

Heart

Trachea, oesophagus, thoracic duct, lymph nodes, phrenic and cardiac veins

Question 34

what are the two pleurae of the lungs and which one is outer?

Answer 34

Parietal (outer)
Visceral
both continuous with one another

Question 35

what are pleural recesses ?

Answer 35

These are potential spaces between the costal and diaphragmatic pleura that the lungs can move into during inspiration.

Question 36

What is thoracentesis and where is the best lace for it?

Answer 36

Thoracentesis is a procedure to remove fluid or air from around the lungs.
Superior to rib to avoid NV bundle.