Gross anatomy of the thorax

Question 1

what heart chamber forms the base of the heart

Answer 1

left atrium

Question 2

what chamber mainly forms the anterior (sternocostal) surface

Answer 2

right ventricle

Question 3

which thorax vertebrae does the base of the heart lie opposite to

Answer 3

T5 - T8

Question 4

what forms the diaphragmatic surface of the heart

Answer 4

mainly the left ventricle and partly by the right ventricle

Question 5

what separates the two ventricles

Answer 5

posterior interventricular groove

Question 6

describe the location of the pericardium in relation to the sternum, costal cartilagesand thoracic vertebrae

Answer 6

• It lies posterior to body of sternum & 2-6 costal cartilages.
• It lies anterior to 5-8 thoracic vertebrae

Question 7

what are the main blood supply and drainage of the pericardium

Answer 7

pericardiacophrenic arteries and veins

Question 8

what is the nerve supply of the fibrous pericardium

Answer 8

phrenic nerve

Question 9

what is the nerve supply of the visceral layer of serous pericardium

Answer 9

branches of the sympathetic trunk and vagus nerves

Question 10

how does fetal circulation differ from the adult one

Answer 10

The fetal circulation differs mainly from the adult one by the presence of 3 major vascular shunts:

• Ductus venosus: between the umbilical vein and inferior vena cava.
• Foramen ovale: between the right and left atrium.
• Ductus arteriosus: between the pulmonary artery and arch of aorta.

Question 11

how does Myocardial Ischaemia

occur and what are the two leading causes

Answer 11

Myocardial ischaemia occurs when the blood flow demands of the heart exceed the blood supplied by the coronary arteries.

The leading causes of myocardial ischaemia are:

• atherosclerosis
• blockage of coronary arteries due to the accumulation of lipid plaques and/or thrombus

Question 12

in what direction do the fibres of the external intercostal muscle go

Answer 12

downward and forward

Question 13

in which direction do the internal intercostal muscles go

Answer 13

downward and backward

Question 14

what is the name of the nerve T12 and why is it called this

Answer 14

subcostal nerve because it arises below the ribs

Question 15

serratus posterior superior:
origin
insertion
innervation
action

Answer 15

spinous processes of C7-T3
superior borders of 2nd-4th ribs
2nd-5th intercostal nerves
elevate ribs

Question 16

serratus posterior inferior
origin
insertion
innervation
action

Answer 16

spinous processes of C7-L2 vertebrae
inferior borders of 8th-12th ribs near their angles
anterior rami to T9-T12 thoracic spinal nerves
depress ribs

Question 17

levator costarum
origin
insertion
innervation
action

Answer 17

transverse processes of C7-T11
subjacent ribs between tubercle and angle
posterior primary rami of C8-T11 nerves
elevate ribs

Question 18

external intercostal
origin
insertion
innervation
action

Answer 18

inferior border of ribs
superior border of ribs below
intercostal nerve
elevate ribs during forced inspiration

Question 19

internal intercostal
origin
insertion
innervation
action

Answer 19

inferior border of ribs
superior border of ribs below
intercostal nerve
interosseous part: depresses ribs
interchondral part: elevates ribs

Question 20

innermost intercostal
origin
insertion
innervation
action

Answer 20

inferior border of ribs
superior border of ribs below
intercostal nerve
interosseous part: depresses ribs
interchondral part: elevates ribs

Question 21

subcostal muscle
origin
insertion
innervation
action

Answer 21

internal surface of lower ribs near their angles
superior border of 2nd or 3rd ribs below
intercostal nerve
interosseous part: depresses ribs
interchondral part: elevates ribs

Question 22

transverses thoracis
origin
insertion
innervation
action

Answer 22

posterior surface of lower sternum
internal surface of costal cartilages 2-6
intercostal nerve
weakly depress ribs

Question 23

what is the foramen ovale

Answer 23

The FORAMEN OVALE is a hole between the right and left atria, allowing blood to pass from the right side to the left and not ever get pumped to the lungs.

Question 24

what is the ductus arteriosus

Answer 24

The DUCTUS ARTERIOSUS allows blood to skip past the lungs and join up with the partially oxygenated blood that is being pumped out of the left ventricle.

Question 25

which ribs are the "floating ribs"

Answer 25

11 and 12

Question 26

between which thoracic vertebrae is the sternum placed

Answer 26

from T2-T9

Question 27

which ribs are the typical ribs

Answer 27

3rd to 9th

Question 28

describe the location of the superior mediastinum

Answer 28

from inlet of thorax to plane extending from level of sternal angle anteriorly to lower border of T4 vertebra posterioly

Question 29

what are the contents of the superior mediastinum

Answer 29

- Thymus - Three veins: > Left brachiocephelic v. > Right brachiocephelic v. > Superior vena cava > arch of aorta and its three branches (brachiocephalic trunk, left common carotid artery and left subclavian artery) > phrenic nerve > vagus nerve > trachea > oesophagus > thoracic duct > arch of azygos > left superior intercostal vein > left recurrent laryngeal nerve (branch of vagus)

Question 30

describe the location of the anterior mediastinum

Answer 30

posterior to body of sternum and attached costal cartilages, anterior to heart and pericardium

Question 31

what are the contents of the anterior mediastinum

Answer 31

- fat - remnants of thymus gland, - anterior mediastinal lymph nodes

Question 32

describe the location of the middle mediastinum

Answer 32

between anterior mediastinum and posterior mediastinum

Question 33

what are the contents of the middle mediastinum

Answer 33

- heart and pericardium - beginning or termination of great vessels - phrenic nerves - pericardiacophrenic vessels - lymph nodes

Question 34

describe the location of the posterior mediastinum

Answer 34

posterior to heart and pericardium, anterior to vertebrae T5－T12

Question 35

what are the contents of the posterior mediastinum

Answer 35

a) oesophagus b) thoracic aorta c) thoracic duct d) azygos venous system - Sympathetic trunks - Thoracic splanchnic nerves

Question 36

what is the function of the phrenic nerves

Answer 36

Both of these nerves supply motor fibres to the diaphragm and sensory fibres to the fibrous pericardium, mediastinal pleura, and diaphragmatic peritoneum.

Question 37

what are the structures and locations where the oesophagus can be compressed

Answer 37

- the junction of the oesophagus with the pharynx in the neck; - in the superior mediastinum where the oesophagus is crossed by the arch of aorta; - in the posterior mediastinum where the oesophagus is compressed by the left main bronchus; - in the posterior mediastinum at the oesophageal hiatus in the diaphragm.

Question 38

describe the distribution of the sympathetic trunk

Answer 38

- T1 – T4 = Thoracic viscera - T5 – T9 or T5 – T10 = Greater splanchnic n - T9 – T10 or T10 – T11 = Lesser splanchnic n - T12 = Least splanchnic n

Question 39

what are the two layers of pericardium

Answer 39

- outer fibrous layer = Fibrous pericardium | - inner serous sac = serous pericardium

Question 40

which costal cartilages does the heart lie posteriorly to and which thoracic vertebrae does the heart lie anteriorly to

Answer 40

- It lies posterior to body of sternum & 2-6 costal cartilages - It lies anterior to 5-8 thoracic vertebrae

Question 41

what is contained in the pericardial cavity and what is its function

Answer 41

- Pericardial cavity contains pericardial fluid | - acts as a lubricant

Question 42

what is the thing that separates the two atria from the ventricles

Answer 42

The 2 atria are separated from ventricles by the atrioventricular groove ( coronary sulcus)

Question 43

what separates the two ventricles

Answer 43

The 2 ventricles are separated by the ant. & post. Interventricular grooves

Question 44

what forms the upper border of the sterno-costal surface of the heart

Answer 44

formed by 2-atria, mainly the left

Question 45

what forms the right border of the sterno-costal surface of the heart

Answer 45

formed only by right atrium

Question 46

what forms the lower border of the sterno-costal surface of the heart

Answer 46

formed mainly by the right ventricle but also by right atrium

Question 47

what forms the left border of the sterno-costal surface of the heart

Answer 47

mainly by the left ventricle & left auricle

Question 48

how many cusps does the aortic valve have

Answer 48

3

Question 49

is the standard view of an x-ray PA or AP

Answer 49

PA

Question 50

what is the normal size for a heart in a chest x-ray

Answer 50

Occupies up to 50% of the maximum internal thoracic diameter on a standard PA erect view

Question 51

between which structures is the tricuspid valve found

Answer 51

right atrium and right ventricle

Question 52

between which structures is the mitral valve found

Answer 52

left atrium and left ventricle

Question 53

what forms the right border of the heart

Answer 53

right atrium

Question 54

what forms the inferior border of the heart

Answer 54

left ventricle and right ventricle

Question 55

what forms the left border of the heart

Answer 55

left ventricle (and some of the left atrium)

Question 56

what forms the superior border of the heart

Answer 56

right and left atrium and the great vessels

Question 57

what makes up the anterior (or sternocostal) division of the heart

Answer 57

Right ventricle

Question 58

what makes up the posterior (or base) division of the heart

Answer 58

Left atrium

Question 59

what makes up the inferior (or diaphragmatic) division of the heart

Answer 59

Left and right ventricles

Question 60

what makes up the | right pulmonary division of the heart

Answer 60

Right atrium

Question 61

what makes up the left pulmonary division of the heart

Answer 61

Left ventricle

Question 62

The right lung contains a horizontal fissure. What rib does this fissure follow the course of?

Answer 62

4th

Question 63

The parasympathetic supply to the lungs is derived from which nerve?

Answer 63

Vagus nerve

Question 64

The mediastinum is divided into superior and inferior compartments by an imaginary line at what vertebral level?

Answer 64

T4

Question 65

What forms the posterior border of the superior mediastinum

Answer 65

Vertebral bodies T1-T4

Question 66

What are the nerve roots of the phrenic nerve

Answer 66

C3,4,5

Question 67

What is the posterior border of the anterior mediastinum?

Answer 67

Pericardium

Question 68

Which muscle forms the floor of the anterior mediastinum?

Answer 68

Diaphragm

Question 69

In adolescents, which organ can be found within the anterior mediastinum?

Answer 69

thymus

Question 70

The sternal angle is formed by the junction of which two bones?

Answer 70

Sternal body and manubrium

Question 71

Which muscle forms the inferior border of the middle mediastinum?

Answer 71

Diaphragm

Question 72

Which of the great vessels of the heart gives rise to the coronary arteries?

Answer 72

Ascending aorta

Question 73

What is the anterior border of the posterior mediastinum?

Answer 73

Pericardium

Question 74

Which part of the aorta is located within the posterior mediastinum?

Answer 74

Descending aorta

Question 75

Via which diaphragmatic hiatus does the thoracic duct enter the posterior mediastinum?

Answer 75

Aortic hiatus

Question 76

Which part of the sternum articulates with the clavicle?

Answer 76

Manubrium

Question 77

Which structures do the sternal articular facets articulate with?

Answer 77

Costal cartilage of the ribs

Question 78

What is the approximate vertebral level of the tip of the xiphoid process?

Answer 78

T10

Question 79

Which option correctly describes the contents of the costal groove? a) Intercostal artery b) Intercostal vein c) Intercostal nerve d) All of the above

Answer 79

d

Question 80

Which part of the vertebrae does the tubercle of each rib articulate with?

Answer 80

Transverse process

Question 81

Which structure does the central tendon of the diaphragm fuse with?

Answer 81

Pericardium

Question 82

Approximately which vertebral level is the oesophageal hiatus situated?

Answer 82

T10

Question 83

What is the innervation of the diaphragm?

Answer 83

Phrenic nerves

Question 84

Which of the following muscles is active during the inspiratory phase of breathing? a) Internal oblique b) Internal intercostals c) External intercostals d) Transversus thoracis

Answer 84

c

Question 85

Transversus thoracis extend from the inferior sternum to the internal costal cartilages of which ribs?

Answer 85

2-6

Question 86

A patient is undergoing a bronchoscopy for removal of a foreign object. At approximately which vertebral level does the trachea bifurcate?

Answer 86

T4

Question 87

Which nerve supplies sensory innervation to the mucosa of the trachea?

Answer 87

Recurrent laryngeal nerve

Question 88

At patient presents with a stab wound to the chest. A open thoracotomy is performed. In which of the following spaces can the superior vena cava be located? a) Posterior mediastinum b) Diaphragmatic caval hiatus c) Entrance to left atrium d) Superior mediastinum

Answer 88

Superior mediastinum

Question 89

The superior vena cava receives tributaries from which vessel?

Answer 89

Azygous vein