Thoracic Wall Muscles

Question 1

Define Axioappendicular muscles and their purpose

Answer 1

extend from thoracic cage to upper limb bone.

help elevate ribs in respiration

Question 2

Which muscles are the accessory muscles in respiration?

Answer 2

Scalene muscles, pectoralis major, pectoralis minor, serratus anterior

Question 3

Name the attachment and function of scalene muscles.

Answer 3

Attachment from neck vertebrae to 1st and 2nd ribs. Fixes the ribs and elevates lower ribs

Question 4

Which muscles are the true thoracic wall muscles?

Answer 4

Serratus Posterior Anterior, Serratus Posterior Interior, Levator Costarum, External Intercostal Muscles, Internal Intercostal Muscles, Innermost Intercostal Muscles, Subcostal, Tranversus Thoracis

Question 5

Describe the Levator Costarum

Answer 5

12 fan shape muscles

Question 6

What is the purpose of the intercostal muscles? Where are they located?

Answer 6

They keep the intercostal spaces rigid so that there’s no bulging during expiration and no drawing in during inspiration. They occupy the intercostal muscles

Question 7

How many pairs in the external intercostal muscles? Most active during?

Answer 7

11 pairs. Most active during inspiration

Question 8

External intercostal muscles are replaced anteriorly by? What’s unique about them?

Answer 8

external intercostal membranes. they run continuously with oblique muscles

Question 9

Internal intercostal muscles are replaced posteriorly by? What’s unique about them?

Answer 9

internal intercostal membranes. they are continuous with internal oblique muscles

Question 10

internal intercostals are weaker than? most active during?

Answer 10

weaker than external intercostal muscles and are most active during expiration.

Question 11

the innermost intercostal muscles are separated by?

Answer 11

intercostal nerves and vessels.

Question 12

subcostal muscles are located where?

Answer 12

lower thoracic wall

Question 13

describe the features of the transversus thoracis muscles.

Answer 13

4 or 5 slips. continuous with transversus abdominis.

Question 14

What is the main purpose of the diaphragm?

Describe its features

Answer 14

primary muscle of inspiration. shared wall separating thorax and abdomen

Question 15

What is passive unless one is exhaling against resistance?

Answer 15

Expiration

Question 16

superior attachment of the serratus posterior superior?

Answer 16

nuchal ligament, spinous processes of C7-T3 Vertebrae

Question 17

inferior attachment of the serratus posterior superior?

Answer 17

superior borders of 2nd to 4th ribs

Question 18

innervation of the serratus posterior superior?

Answer 18

2nd to 5th intercostal nerves

Question 19

main action of the serratus posterior superior?

Answer 19

proprioception - elevate ribs

Question 20

superior attachment of the serratus posterior inferior?

Answer 20

spinous processes of T11 to L2

Question 21

inferior attachment of the serratus posterior inferior?

Answer 21

inferior borders of 8th to 12th ribs near their angles

Question 22

innervation of the serratus posterior inferior?

Answer 22

anterior rami to T9 to T12 thoracic spinal nerves

Question 23

action of the serratus posterior inferior?

Answer 23

proprioception - depress ribs

Question 24

superior attachment of levator costarum.

Answer 24

transverse processes of T7-11

Question 25

inferior attachment of levator costarum.

Answer 25

subjacent ribs between tubercle and angle

Question 26

innervation of levator costarum

Answer 26

posterior primary rami of C8-T11

Question 27

action of levator costarum.

Answer 27

elevate ribs

Question 28

superior attachment of external, internal and innermost intercostal muscles.

Answer 28

inferior border of ribs

Question 29

inferior attachment of external, internal, innermost intercostal muscles

Answer 29

superior border of ribs below

Question 30

innervation of the external, internal, innermost intercostal muscles

Answer 30

intercostal nerve

Question 31

action of the external intercostal muscles.

Answer 31

elevate ribs during forced inspiration

Question 32

action of the internal intercostal and innermost intercostal muscles.

Answer 32

interosseous part: depresses ribs interchondral part: elevates ribs during active respiration

Question 33

superior attachment of the subcostal muscles.

Answer 33

internal surface of lower ribs near their angles

Question 34

inferior attachment of the subcostal muscles.

Answer 34

superior borders of 2nd or 3rd ribs below

Question 35

innervation of the subcostal muscles.

Answer 35

intercostal nerve

Question 36

action of the subcostal muscles

Answer 36

probably the same as internal intercostal muscles

Question 37

superior attachment of the transversus thoracis

Answer 37

posterior surface of the lower sternum

Question 38

inferior attachment of the transversus thoracis

Answer 38

internal surface of costal cartilages 2-6

Question 39

innervation of the transversus thoracis

Answer 39

intercostal nerves

Question 40

action of the transversus thoracis

Answer 40

weakly depress ribs. proprioception