muscles of thoracic wall (7)

Question 1

whats this

Answer 1

external intercostal (superficial layer)
sup attachment : inferior border of ribs
inferior attachment: superior border of ribs below
innervation: intercostal nerves
main action: elevates ribs during forced inspiration

Question 2

whats this

Answer 2

internal intercostals (middle layer)
sup attachments: inferior border of ribs
inferior attachments: superior border of ribs below
innervation: intercostal nerves
main action: interosseous part depresses ribs; interchondral part elevates ribs during forced respiration

Question 3

whats this

Answer 3

innermost intercostal (deep layer)
sup attachments: inferior border of ribs
inferior attachment: superior border of rib below
innervation: intercostal nerves
main action: interosseous part depresses ribs; interchondral part elevates ribs

internal to intercostal neurovasculature

Question 4

upper limb muscles that attach to thoracic cage

Answer 4

pec major, pec minor, serrates anterior and latissimus dorsi

Question 5

which muscles can function as accessory muscles of respiration

Answer 5

pec major, pec minor, inferior part of serrates anterior, scalene muscles

Question 6

external intercostal membranes

Answer 6

replace external intercostal muscles, anteriorly near sternum

Question 7

internal intercostal membranes

Answer 7

replace internal intercostal membranes, posteriorly

Question 8

what are these guys

Answer 8

serretus posterior superior: elevates the ribs during inspiration/stabilizes thorax
serretus posterior inferior : helps draw the lower ribs inferiorly and posteriorly

Question 9

dermatomes

Answer 9

band like skin areas that are supplied by sensory fibres of a single spinal nerve root. overlapping of adjacent dermatomes usually occurs.

Question 10

myotomes

Answer 10

motor fibres of the spinal nerves supply the muscles.

Question 11

parts of diaphragm

Answer 11

• sternal part
• right costal part
• left costal part
• left crus: extend from diaphragm to vertebral column
• right crus : form a tether that which helps in muscular contraction
• lumbar part