Muscles that move the Ribs

Question 1

3 layers of intercostal muscles

Answer 1

• External
• Internal
• Innermost

Question 2

Where do the external intercostals originate and insert?

Answer 2

• O = inferior border of rib above
• I = superior border of rib below

Question 3

Which direction do the muscles fibres of the external intercostals run in?

Answer 3

Anteriorly, from above to below

Question 4

Where do the internal intercostals originate and insert?

Answer 4

• O = superior border of rib below
• I = inferior border of rib above

Question 5

Which direction do the muscles fibres of the internal intercostals run in?

Answer 5

Anteriorly, from below to above

Question 6

Where do the innermost intercostals originate and insert?

Answer 6

• O = superior border of rib below
• I = inferior border of rib above

Question 7

Which direction do the muscles fibres of the innermost intercostals run in?

Answer 7

Anteriorly, from below to above

Question 8

Action of external intercostals

Answer 8

Elevate rib below above and outwards

Question 9

Action of internal intercostals

Answer 9

Depress rib above down and inwards

Question 10

Action of innermost intercostals

Answer 10

Depress rib above down and inwards

Question 11

Between which muscles is the neurovascular bundle found?

Answer 11

• Internal intercostals
• Innermost intercostals

Question 12

At what level does the IVC pass through the diaphragm?

Answer 12

T8

Question 13

At what level does the oesophagus pass through the diaphragm?

Answer 13

T10

Question 14

At what level does the aorta pass through the diaphragm?

Answer 14

T12

Question 15

Arcuate ligaments of the diaphragm (medial to lateral)

Answer 15

• Median arcuate ligament
• Medial arcuate ligament
• Lateral arcuate ligament

Question 16

What are the crura (sing. crus)?

Answer 16

Tendinous structures that extend from the posterior aspect of the diaphragm down the vertebral column