The Thoracic Wall

Question 1

An axial slice at the level of the xiphoid process anteriorly and the body of T9 posteriorly indicates the level of:

Answer 1

1- superior border of the liver

2- inferior border of the heart

3- the central diaphragmic tendon

Question 2

marks the superior level of the pericardium and the superior limit of the pulmonary trunk

Answer 2

Sternal angle

Question 3

Shows the level of the beginning and end of the arch of aorta

Answer 3

Sternal angle

Question 4

is the level at which the trachea bifurcates into R and L main bronchi

Answer 4

Sternal angle

Question 5

Sternal angle

Answer 5

An axial slice through the sternal angle:

ant: sternal angle
pst: T4-T5 intervertebral discs

Question 6

List 4 of the structures marked/shown by an axial slice through the sternal angle anteriorly and the T4/T5 intervertebral disc posteriorly:

Answer 6

1- sup level of pericardium

2- sup limit of the pul. trunk

3- arch of aorta begins and ends

4- trachea divides into R/L main bronchi

5- rib II articl8 w/ sternum

Question 7

Protection of intercostal vasculatures

Answer 7

The intercostal vein and artery lie in costal groove and are protected by bone. The intercostal nerve is not typically protected by bone.

Question 8

Costal groove

Answer 8

The ribs shaft has a groove on the inf. margin of its internal surface. Intercostal aa and vv lie in this groove.

Question 9

Crest of the head

Answer 9

the head of a typical rib is wedge-shaped and is divided into two facets by the crest of the head.

Question 10

The tubercle for serratus anterior is located on its superior surface.

Answer 10

Rib II

Question 11

It has a singular articular facet on its head for articulation with T1

Answer 11

Rib 1

Question 12

Ant. scalene muscle inserts into this rib

Answer 12

Rib I (Scalene tubercle)

Question 13

Short ribs without a neck or tubercle

Answer 13

11 and 12

Question 14

Ribs with one facets on their heads ( articulation with single vertebrae)

Answer 14

1 and 10-12

Question 15

Demifacets on each side of the vertebral body articulate with —— while transverse costal facets articulate with the —– of the ribs.

Answer 15

head, tubercles

Question 16

Has a complete superior costal facet instead of a demifacet.

Answer 16

T1

Vertebra T1 has a complete superior costal facet instead of a demifacet. The head of rib 1 does not articulate with vertebra C7.

Question 17

a single complete costal facet for articulation with the same-numbered rib.

Answer 17

vertebrae T10-12

Question 18

lack transverse costal facets on their transverse processes.

Answer 18

Vertebrae T11 & T12

Vertebrae T11 and T12 lack transverse costal facets on their transverse processes. Ribs 11 and 12 do not articulate with the transverse processes.

Question 19

Joints of costal articulation

Answer 19

1- Costochondral joints
2- Sternocostal joints
3- Costotransverse joints
4- Costovertebral joints (joint of head of rib)

Question 20

Costovertebral and costotransverse joints are

Answer 20

synovial joint

Question 21

Costovertebral joint

Answer 21

The head of a typical rib articulates with the superior demifacet of the same-numbered vertebra and the inferior demifacet of the vertebra above it to form a joint of head of rib (synovial joint).

Question 22

Costotransverse joint

Answer 22

The tubercle of the rib articulates with the transverse process of the same-numbered vertebra to form a costotransverse joint (synovial joint).

Question 23

The types of the sternocostal joints

Answer 23

Rib I- Synchondrosis (fibrocartilaginous)

Ribs II- VII- Synovial

Question 24

Costochondral joints

Answer 24

The bodies of ribs articulate with their costal cartilages at fibrocartilaginous joints known as costochondral joints.

Question 25

Sternocostal joints

Answer 25

The costal cartilages of the 7 true ribs articulate with the sternum at sternocostal joints.

Question 26

Interchondral joints

Answer 26

The costal cartilages of ribs 7-10 articulate with the cartilage above at synovial joints known as interchondral joints.

Question 27

The contents of intercostal space (general)

Answer 27

``` intercostal muscles (3 layers) intercostal nn and bv ```

Question 28

From the costochondral junctions to the sternum, the muscles are replaced by

Answer 28

external intercostal membrane

Question 29

External intercostal membrane

Answer 29

orientation: forward and down | replaced by external intercostal membrane starting from costochondral junctions

Question 30

Internal intercostal membrane

Answer 30

“backward & down” | Posterior and medial to the angles of the ribs, the muscles are replaced by the internal intercostal membrane

Question 31

innermost intercostal muscle

Answer 31

similar to the internal intercostal muscle

Question 32

innervation of the intercostal muscles

Answer 32

intercostal nn. | T12 n is subcostal n

Question 33

subcostal n.

Answer 33

T12 n. is subcostal

Question 34

Transversus thoracis m. Subcostal m. Also innervated by

Answer 34

intercostal nn.

Question 35

Contents of intercostal space (specific)

Answer 35

Posterior intercostal Vein Posterior intercostal Artery From thoracic aorta Intercostal Nerve Anterior intercostal artery From internal thoracic artery Form the VAN

Question 36

Orientation of intercostal a and v

Answer 36

intercostal v is sup to a. | Both V and A are protected by the costal groove.

Question 37

Orientation of the intercostal n

Answer 37

Inf. to the intercostal a.

Question 38

The location of intercostal VAN

Answer 38

lies b/w the internal and innermost intercostal muscles.

Question 39

Intercostal nn

Answer 39

Ant ramus of a thoracic spinal nerve. | Gives off lateral and anterior cutaneous branches

Question 40

The arterial supply to the thoracic wall comes from the:

Answer 40

Thoracic aorta Subclavian a Axillary a

Question 41

Thoracic aorta supplies the thoracic wall via

Answer 41

the pst. intercostal and subcostal aa.

Question 42

Subclavian a. supply the thoracic wall via

Answer 42

internal thoracic and supreme intercostal aa.

Question 43

Axillary a. supply the thoracic wall via

Answer 43

sup. and lat. thoracic aa.

Question 44

The posterior intercostal arteries give rise to -----.

Answer 44

The posterior intercostal arteries give rise to branches that accompany the posterior rami of the spinal nerves and the lateral cutaneous branches of the intercostal nerves.

Question 45

The posterior intercostal arteries of intercostal spaces 3-11 (and the subcostal arteries) arise -----.

Answer 45

The posterior intercostal arteries of intercostal spaces 3-11 (and the subcostal arteries) arise posteriorly from the thoracic aorta.

Question 46

The posterior intercostal arteries of intercostal spaces 1 and 2 arise from -----.

Answer 46

The posterior intercostal arteries of intercostal spaces 1 and 2 arise from the supreme (superior) intercostal artery, a branch of the costocervical trunk.

Question 47

The internal thoracic arteries terminate in the sixth intercostal space by dividing into the ----- and -----arteries.

Answer 47

Superior epigastric and musculophrenic arteries.

Question 48

The internal thoracic arteries arise in the root of the neck from the -----surfaces of the ----- arteries.

Answer 48

From the inferior surfaces of the subclavian arteries.

Question 49

The internal thoracic arteries descend on the ----- surface of the thorax ----- to the sternum and ----- to the clavicle and upper six costal cartilages.

Answer 49

internal surface lateral to the sternum posterior to the clavicle

Question 50

Spaces without anterior intercostal aa.

Answer 50

Intercostal spaces 10-11

Question 51

The anterior intercostal arteries of intercostal spaces 1-6 arise from the -----.

Answer 51

internal thoracic aa.

Question 52

The anterior intercostal arteries of spaces 7-9 arise from -----.

Answer 52

musculophrenic aa.

Question 53

The anterior and posterior intercostal arteries have -----and ----- branches that anastomose with each other.

Answer 53

terminal and collateral

Question 54

The intercostal veins accompany the intercostal arteries and nerves and lie most superior in the -----.

Answer 54

costal grooves

Question 55

The posterior intercostal veins anastomose with the ----- veins.

Answer 55

anterior intercostal

Question 56

Most posterior intercostal veins drain into the ----- , while the anterior intercostal veins drain into the -----.

Answer 56

pst- azygos system of veins ant- internal thoracic veins

Question 57

The internal thoracic veins accompany the -----.

Answer 57

internal thoracic arteries

Question 58

The breast

Answer 58

Breast tissue is typically found overlying the pectoralis major m. Overlies ribs 2-6 from sternum to midaxillary line location of the nipple will vary according to the size and shape of the breast The nipple contains the openings of the 15-20 lactiferous ducts

Question 59

The mammary glands are enclosed in

Answer 59

superficial fascia/ subcutaneous connective tissue.

Question 60

suspensory ligament

Answer 60

variable amt of fat and bands of fibrous CT

Question 61

retromammary space

Answer 61

separates the breast from deep fascia over pectoralis major by loose CT. It also allows some movement over the chest wall.

Question 62

Allows minor movement of the breast over chest wall

Answer 62

retromammary space

Question 63

The axillary tail

Answer 63

breast tissue extend into axilla. | Significant during breast examination

Question 64

Blood supply of the breast

Answer 64

Mainly from mammary branches of: internal thoracic artery lateral thoracic artery posterior intercostal arteries

Question 65

Venous drainage of the breast

Answer 65

Has a venous drainage roughly mirroring its arterial supply: | tributaries of the posterior intercostal veins may carry cancer cells to the vertebral venous plexus.

Question 66

lymphatic drainage of the breast

Answer 66

60-75% of lymph from the breast drains into the axillary nodes Very important in understanding the mechanisms of metastasis of breast cancer