Muscles of Thoracic Wall

Question 1

muscles of thorax

Answer 1

Pectoralis
Serratus anterior
Serratus posterior
External intercostals

Question 2

Serratus posterior superior

Answer 2

Superior attachment- nuchal ligament, spinous processes of C7 to T3
Inferior attachment - superior borders of 2nd to 4th ribs
Innervation- 2 to 5 intercostal nerves
action - proprioception elevate ribs

Question 3

serratus posterior inferior

Answer 3

superior attachment- spinous processes of T11 to L2
Inferior attachment - inferior borders of 8 to 12 ribs near angles
Innervation - anterior rami T9 - T12 thoracic spinal nerves
action - proprioception depress ribs

Question 4

Levator costarum

Answer 4

superior attachment- transverse processes of C7 to T11
Inferior attachment - subjacent ribs between tubercle and angle
Innervation - posterior primary remind of C8 - T11
Action - elevate ribs

Question 5

external intercostal

Answer 5

Superior attachment- inferior border of ribs
Inferior attachment - superior border of ribs
Innervation - intercostal nerve
Action - elevate ribs during forced inspiration

Question 6

Internal intercostal

Answer 6

superior attachment- inferior border of ribs
Inferior attachment - superior border of ribs
Innervation- intercostal nerve
Action- interosseous part- depress ribs
Interchondral part - elevate rib
During active forced respiration

Question 7

innermost intercostal

Answer 7

superior attachment- inferior border of ribs
Inferior attachments - superior border of ribs
Innervation - intercostal nerve
Action - interosseous part- depresses ribs interchondral part- elevates ribs
During active forced respiration

Question 8

Subcostal

Answer 8

superior attachment- internal surface of lower ribs near the angle
Inferior attachment - superior borders of second and third ribs below
Innervation - intercostal nerve
Action - probably act in the same manner as internal intercostal muscles

Question 9

transverses thoracis

Answer 9

Superior attachment- posterior surface of lower sternum
Inferior attachment - internal surface of costal cartilage 2 to 6
Innervation - intercostal nerve
Action - weekly depress ribs proprioception

Question 10

Internal intercostals location

Answer 10

11 pairs of muscles
deep to the external intercostals
run obliquely at right angles to external intercostals
Posteriorly, they formed the internal intercostal membrane

Question 11

Innermost, intercostals location

Answer 11

11 pairs that room similar to the Internal intercostals

separated from the internal intercostals by the intercostal nerves and vessels

Cover the middle 3/4 of the intercostal space

Question 12

Subcostal muscles location

Answer 12

thin muscular slips that extend from the angle of the rib on the internal surface to internal surface of rib below

Cross into intercostal spaces

Run the same direction as internal intercostals

Question 13

Transversus thoracis location

Answer 13

four or five muscular slips that arise from the xiphoid and body of the sternum

Span superiorly, and laterally to the 2nd to 6th costal cartilages

Question 14

levatores costarum

Answer 14

12 fan shaped muscles

Arise on the transverse processes of C7 to T11

Inferiorly and laterally insert on ribs below

Question 15

intercostal nerves

Answer 15

ventral primary rami of the first 11 thoracic spinal nerves

12 thoracic spinal nerve is called a subcostal nerve

Question 16

intercostal arteries

Answer 16

Each intercostal space supplied by….

Large posterior intercostal artery arising from the aorta
Small anterior intercostal artery arising from the internal thoracic artery

Question 17

Internal thoracic artery arises from what

Answer 17

Arises from the subclavian artery

Question 18

Extrinsic muscles

Answer 18

diaphragm
Pectoral muscles
Scalenes
Sternocleidomastoid

Question 19

Intrinsic muscles

Answer 19

external intercostals
Internal intercostals
Innermost intercostals
Subcostal muscles
Transverses thoracis
levatores costarum

Question 20

How many synovial joints at each level?

Answer 20

Six

2 zygapophyseal
2 costotransverse
2 costovertebral