4.2.3 Thoracic Wall and Lung Cavities

Question 1

Identify the structures.

Answer 1

Question 2

Where is the thorax located?

Answer 2

B/t the neck and abdomen

Question 3

What are the key skeletal elements of the thorax?

Answer 3

12 thoracic vertebrae

12 ribs and costal cartilages

1 sternum

Question 4

What are the components of the sternum?

Answer 4

Manubrium, body, xiphoid process

Question 5

What are the three types of ribs? Which ribs belong to each of these classifications?

Answer 5

True ribs (1-7): attach directly to sternum

False ribs (8-10 or some say 8-12): costal cartilages do not directly attach to sternum)

Floating ribs (11-12): lack costal cartilage

Question 6

Which ribs are included in the typical ribs? What are there four common structures?

Answer 6

3-9

Head, tubercle, shaft/body, and angle of rib

Question 7

What is the most frequent site of rib fractures?

Answer 7

Just lateral to the angle of the rib

Question 8

How many facets does the head of true ribs have?

Answer 8

2, a superior and inferior facet

Question 9

What are these components of the ribs?

Answer 9

Question 10

The scalene tubercle in the 1st rib is the site of attachment for which muscle?

Answer 10

anterior scalene m.

Question 11

What is another name for the sternal angle?

Answer 11

Angle of Lewis

Question 12

If which structure is left intact, will it allow for possible regeneration of the rib?

Answer 12

Periosteum

Question 13

Where is the 13th rib usually located?

Answer 13

On C7

about 0.5 to 1% of the population has a cervical rib

Question 14

What is circumscribed in green? What is the dense fibrous band connecting it to?

Answer 14

The cervical rib; the dense fibrous band is connecting it to the 1st rib

Question 15

What condition is associated with the presence of the cervical rib?

Answer 15

Venous Thoracic Outlet Syndrome

(Fun fact: Your fellow classmate THE Miles Sanderson had this syndrome, which led to a blood clot in his shoulder.)

Question 16

Where do the ribs 1-7 articulate with the stenurm?

Answer 16

Question 17

What 4 bodily landmarks occur at the level of the sternal angle (the junction of the manubrium with body of sternum)?

Answer 17

Attachment of the 2nd rib

intervertebral level at disc b/t T4 and T5

bifurcation of trachea

azygos veins drains into the SVC

Question 18

Where are the regions of the mediastinum located?

Answer 18

Question 19

What commorbidity is often associated with pectus excavatum?

Answer 19

Mitral valve prolapse

Question 20

What is pectus carinatum?

Answer 20

Ridge projecting anteriorly (more rare than excavatum)

Question 21

In what patient population is pectus carinatum most likely to develop?

Answer 21

11 to 14 y/o pubertal males undergoing a growth spurt

Question 22

What is the name of the joint between the ribs and its corresponding vertabrae?

Answer 22

Costovertebral joint, it’s a synovial joint b/t head of rib and body of vertebra at a facet or demifacet

Question 23

The costotranverse joint is a synovial joint b/t what two structures?

Answer 23

tubercle of the rib and the transverse process of the vertebra

Question 24

In which ribs is the costotranverse joint fairly curved? fairly flat?

Answer 24

Curved: 1-7

Flat: 8-12

Question 25

What type of joints are the sternocostal joints?

Answer 25

Cartilaginous

Question 26

What is costochondritis? In what population is it most common?

Answer 26

Chest pain due to inflammation of the cartilage and bones in the chest wall.

Overuse injury in athletes

Question 27

What the three layers of the intercostal muscles?

Answer 27

External, internal, and innermost

The external runs down and medial on both sides (like putting hands into front pockets), and the internal and innermost run direction 90 degrees to that

Question 28

Where do the intercostal nerves run?

Answer 28

Between the internal and innermost intercostal muscle (b/t I and I)

Question 29

What is different about the subcostal muscles?

Answer 29

They “skip” a rib

Found on the posterior portion of thoracic wall

Question 30

Where does the pectoralis major originate and insert? pectoralis minor? serratus anterior muscle?

Answer 30

Question 31

Where are the lateral cutaneous and anterior cutaneous branches given of the intercostal nerves?

Answer 31

Question 32

Which vein seperates the pectoralis major and the deltoid?

Answer 32

Cephalic vein

Question 33

Describe the typical positioning of artery, vein, and nerve from cranial to caudal under the groove of each rib?

Answer 33

VAN

V: vein

A: artery

N: nerve

Question 34

What is shingles?

Answer 34

A reactivation of a latent herpes varicella-zoster viral infection

Question 35

What is a dermatome? Where are dermatomes C5, T4, T7, T10, L1

Answer 35

An area of the skin which receives innervation from a single spinal nerve.

C5: clavicle

T4: “teat”, nipple

T7: xiphoid process (pointy)

T10: umbilicus (O reminds you of the umbilicus)

L1: inguinal ligament

Question 36

~75% of the breast is drained into which lymph nodes?

Answer 36

Axillary lymph nodes

Question 37

What is polythelia? In what population is it most common?

Answer 37

Supernumerary nipple(s) which may appear similar to a mole, anywhere along the mammalian lines (milk lines)

Males

Question 38

What is polymastia? When is most liked noticed?

Answer 38

Additonal breast along the milk line b/t the axilla and groin.

Rare, most likely noticed at the time of pregnancy due to enlargement and possible production of milk

Question 39

What is gynecomastia?

Answer 39

Excessive development of the male mammary gland

Question 40

What is contained in the mediastinum?

Answer 40

heart, great vessels, trachea, esophagus, and thymus

Question 41

Which muscle acts as the principal muscle of inspiration?

Answer 41

Diaphragm

Question 42

The are two pectoral nerves? Which pectoralis muscles do they innervate?

Answer 42

Lateral and Medial Pectoral Nerve

Medial pectoral nerve innervates both the major and minor pectoralis

Lateral pectoral nerve only innervates the pectoralis major