The Thoracic Wall

Question 1

thorax

Answer 1

part of body b/n neck & diaphragm

Question 2

mid-clavicular line

Answer 2

imaginary line running vertically downward from the midpoint of the clavicle

Question 3

mid-axillary line

Answer 3

imaginary line running vertically downward from mid-axilla

Question 4

manubrium:

part of the ___

lies at the level of ___

jugular (suprasternal) notch: ___

articulates with the ___

lower border articulates with the ___

rib 2 lies at the ___

Answer 4

sternum

T3 - T4

concave center of the upper border

clavicles & the 1st & upper part of the 2nd rib

body (manubriosternal joint, sternal angle of Louis)

manubriosternal joint

Question 5

body (part of the sternum):

lies at the level of ___

articulates with ___

rib 7 lies at the ___

Answer 5

T5 - T9

ribs 2-7

xiphosternal joint

Question 6

xiphoid process:

part of the ___

lies at the level of ___

Answer 6

sternum

T10

Question 7

true ribs

Answer 7

vertebrosternal

upper 7 pairs

attached anteriorly to the sternum by costal cartilages

Question 8

false ribs

Answer 8

lower 5 pairs

vertebrochondral ribs (8, 9, 10) - attached to each other & to 7th rib by their costal cartilages (connection to sternum is indirect)

free/floating ribs (11 & 12) - have no anterior attachment

Question 9

typical ribs

Answer 9

ribs 3-9

Question 10

typical ribs:

head

Answer 10

two facets for articulation w/ the corresponding vertebral bodies & the body above

Question 11

typical ribs:

tubercle

Answer 11

facet for the transverse process of the corresponding vertebra

Question 12

typical ribs:

neck

Answer 12

constriction b/n head & tubercle

Question 13

typical ribs:

shaft/body

Answer 13

thin, twisted, contains a costal groove along the inferior border

Question 14

typical ribs:

costal groove

Answer 14

contains (superior to inferior): VAN

• intercostal vein
• intercostal artery
• intercostal nerve

Question 15

typical ribs:

costal angle

Answer 15

where the shaft bends sharply forward

Question 16

atypical ribs:
first rib

important b/c ___

___ than other ribs

almost ___

___ for first vertebral body

scalene tubercle: ___

• subclavian vein crosses rib ___ to scalene tubercle
• subclavian artery & inferior trunk of brachial plexus cross rib ___ to scalene tubercle

Answer 16

of its relationship to the brachial plexus & large vessels of the arm

shorter & wider

horizontal

head single facet

insertion of the scalenus anterior muscle (near inner border)

• anterior
• posterior

Question 17

atypical ribs:

second rib

Answer 17

main atypical feature is a rough area on its upper surface, the tuberosity for the serratus anterior muscle

Question 18

atypical ribs:

10, 11, & 12

Answer 18

single facet of head for bodies of corresponding vertebrae

Question 19

atypical ribs:

11 & 12

Answer 19

no tubercles or facets for transverse processes

Question 20

intercostal muscle nerve supply

Answer 20

intercostal nerves

Question 21

external intercostal muscles:

pass ___ from the rib above to the rib below

conform to the ___ muscles of the ___

extend from the ___ posteriorly to the ___ anteriorly

replaced anteriorly by the ___

Answer 21

downward & forward

external oblique, abdomen

rib tubercle, costochondral junction

external intercostal membrane

Question 22

internal intercostal muscles:

pass ___ from rib above to rib below

conform to the ___ muscles of the ___

extend from ___ anteriorly to ___ posteriorly

replaced posteriorly by the ___

Answer 22

downard & backward

internal oblique, abdomen

sternum, angles of ribs

internal intercostal membrane

Question 23

innermost intercostal layer:

___ than the other two intercostal muscles

best distinguished by the fact that they ___

the ___ of both the thoracic & abdominal walls lies b/n the middle & deepest layer of muscles

Answer 23

less well developed

are separated form the internal intercostal muscles by the neurovascular bundles

neurovascular plane

Question 24

innermost intercostal layer:

innermost intercostal muscles (intercostalis intimi)

Answer 24

similar to internal intercostal muscles

Question 25

innermost intercostal layer:
subcostal muscles:

pass from ___

usually span ___

parallels direction of the ___

Answer 25

inside angle of one rib to rib two levels inferior

two intercostal spaces

internal intercostal muscles

Question 26

innermost intercostal layer:
transversus thoracis:

___ fan out from the ___

continuous inferiorly w/ the ___

Answer 26

4-5 slips of muscle, inferior part of sternum to costal cartilages 2-6

transversus abdominus muscle

Question 27

intercostal nerves:

___ of the first ___ nerves

subcostal nerve: ___

after giving off the ___, the ___ continues in the direction of the original spinal nerve

each intercostal nerve enters the space b/n the ___ & the ___, then continues forward between the ___ & the ___

Answer 27

ventral rami, 11 thoracic

ventral ramus of T12 lies below 12th rib

dorsal ramus, ventral ramus

parietal pleura, internal intercostal membrane, internal intercostal muscles, innermost layer

Question 28

atypical nerves:
first intercostal nerve:

represents ___

major part of the ___ joins the ___

Answer 28

only a small portion of the ventral ramus of T1

ramus, brachial plexus

Question 29

atypical nerves:
second intercostal nerve (sometimes also third intercostal nerve):

lateral cutaneous branch (intercostobrachial nerve): ___

in coronary artery disease, ___ is referred along this nerve to the medial side of the arm

Answer 29

joins the medial cutaneous nerve of the arm & helps supply the skin of the axilla (armpit) & upper medial arm

pain

Question 30

atypical nerves:
7th - 11th intercostal nerves:

leave the ___ & continue into the ___

continue in the ___

Answer 30

intercostal spaces, abdominal wall

same plane (b/n the internal oblique & transversus abdominus muscles)

Question 31

atypical nerves: 
subcostal nerve (T12)

Answer 31

follows course of 7th-11th intercostal nerves

Question 32

intercostal arteries

Answer 32

each space contains one large posterior intercostal artery & two small anterior intercostal arteries

Question 33

posterior intercostal arteries:

first two spaces: ___

lower nine spaces: ___

continue into the ___

Answer 33

branches of the supreme intercostal artery (which itself is a branch of the costocervical trunk of the subclavian artery)

direct branches from the thoracic aorta

abdominal wall w/ the corresponding nerves

Question 34

anterior intercostal arteries:

upper six spaces: ___

lower anterior intercostals & subcostal artery: ___

Answer 34

branches of the internal thoracic artery, anastomose laterally w/ the posterior intercostal arteries

branches of the musculophrenic artery (one of the terminal branches of the internal thoracic artery), continue into abdominal wall w/ corresponding nerves

Question 35

internal thoracic artery (internal mammary artery):

branch of the ___

descends in the ___

divides behind the ___ into two terminal branches: ___ & ___

Answer 35

subclavian artery in the root of the neck

thorax just lateral to the sternum, anterior to the transversus thoracis muscle

6th costal cartilage, superior epigastric artery, musculophrenic artery

Question 36

branches of the internal thoracic artery

Answer 36

upper six anterior intercostal arteries

pericardiophrenic artery

perforating branches

Question 37

internal thoracic artery (internal mammary artery):

pericardiophrenic artery

Answer 37

runs w/ phrenic nerve

supplies the pericardium, diaphragm, & part of the pleura

Question 38

internal thoracic artery (internal mammary artery):

perforating branches

Answer 38

pass to the skin w/ the anterior cutaneous branches of the intercostal nerves

contribute to the blood supply of the breast & enlarged in women during lactation

Question 39

veins:

all ___ are accompanied by corresponding veins

the posterior intercostal veins empty into the ___ veins

anterior intercostal veins: ___

internal thoracic vein: ___

Answer 39

arteries

azygous & hemiazygous

drain into the musculophrenic vein or the internal thoracic vein

drains into the brachiocephalic vein