Muscles

Question 1

External Intercostals

Answer 1

O: inferior ribs above 1-11
I: Superior ribs below 2-12
A: Maintain ICS during respiration, elevate ribs during inspiration
N:Intercostal nerves
run infero-medially
replaced ANTERIORALLY by external intercostal membrane

Question 2

Internal intercostals

Answer 2

O: Superior ribs below
I: inferior part of ribs above
A: maintain ICS during respiration, depress ribs during expiration
N:Intercostal nerves
run inferolaterally
replaced POSTERALLY by external intercostal membrane

Question 3

Innermost intercostal

Answer 3

O: superior part of ribs near angle
I: inferior part of ribs above
A: Maintain ICS during respiration, depress ribs during expiration
N:Intercostal nerves

Question 4

Subcostal

Answer 4

O: superior part of ribs near angle
I:inferior border of rib 2 or 3 or ICS higher
A: depress ribs during expiration
N:Intercostal nerves

Question 5

Transverse Thoracic

Answer 5

O: internal surface of inferior sternum
I: inferior border of ribs 2-6
A: depress ribs during expiration
N:Intercostal nerves 2-6

Question 6

Levator cosatrum

Answer 6

O: TPs of CV7-TV11
I: ribs 9-12 inferior near angle
A: assist with elevating ribs during forced inspiration
N: Ventral rami of C8-T11

Question 7

Serratus Posterior Superior

Answer 7

O: Nuchal ligament and SPs of C7-T3
I: ribs 2-5 lateral to angle
A: Elevates ribs during inspiration
N: Intercostal nerves T1-4

Question 8

Serratus Posterior inferior

Answer 8

O: SPs of T11-L2
I: ribs 9-12 lateral to angle
A: depresses lower four ribs allowing diaphram to act during inspiration
N: Intercostal nerves T9-T11