Respiratory Anatomy 1.2

Question 1

What are the external intercostal muscles replaced with anteriorly?

Answer 1

External intercostal membranes

Question 2

What are the internal intercostal muscles replaced with posteriorly?

Answer 2

Internal Intercostal membrane

Question 3

Where do innermost muscles exist?

Answer 3

Only in the middle of the thoracic cage.

Question 4

What is the arterial supply of this thoracic wall?

Answer 4

Posterior intercostal arteries which are a branch of the descending thoracic aorta. Anterior intercostal arteries are a branch of the internal thoracic arteries which are a branch of the subclavian artery. It is also suppled by branches from axillary arteries.

Question 5

What is the venous supply of this thoracic wall?

Answer 5

The azygous vein which drains into the superior vena cava.
Accessory hemiazygous vein and hemiazygous vein which both drain into azygous vein
Internal thoracic vein which drains into the subclavian vein which all go the vena cava superior to the right atrium.

Question 6

What is the lymphatic drainage of the thoracic wall?

Answer 6

Right side of the chest drains into the right lymphatic duct which drains into the right subclavian vein.
Left side of the chest drains into the thoracic duct which drains into the angle between the subclavian vein and the internal jugular vein
Breast drains into the axillary lymph nodes, parasternal lymph nodes and abdominal lymph nodes.

Question 7

What is a dermatome?

Answer 7

Area of the skin supplied by a single spinal nerve.

Question 8

How may pairs of spinal nerves are supplied to the thoracic wall?

Answer 8

12

Question 9

What is a myotome?

Answer 9

A single spinal nerve that supplies a muscle.

Question 10

What is the cavity in the middle of the thorax called?

Answer 10

Mediastinum

Question 11

What can the mediastinum be divided into?

Answer 11

Superior and inferior

Question 12

What 3 sections can be the inferior mediastinum be divided into?

Answer 12

Anterior, middle and posterior.

Question 13

What does the mediastinum contain?

Answer 13

It contains the heart , vessels, oesophagus, thymus and lymph nodes.

Question 14

What splits the thoracic cavity?

Answer 14

Pericardial sac

Question 15

What covers the mediastinum?

Answer 15

It’s covered by the mediastinal pleura

Question 16

What is the diaphragm?

Answer 16

Fibro-muscular septum

Question 17

What does the diaphragm do?

Answer 17

It separates the thoracic cavity from the abdominal cavity.

Question 18

Where are the three attachments of the diapragm?

Answer 18

Lumbar vertebrae
Costal cartilages of rib 7 to 12
Xiphoid process of sternum

Question 19

Where is the central attachment?

Answer 19

Cetral tendon of the diaphragm which is attached to fibrous pericardium

Question 20

What are crura?

Answer 20

They are the right and left part of the diaphragm that arise from the vertebrae and are tendinous in nature

Question 21

Where does the right crus arise from?

Answer 21

L1 - L3

Question 22

Where do some of the fibres of the right crura surround?

Answer 22

the oesophageal opening and help prevent reflux of gastric contents back into the oesophagus.

Question 23

Where does the left crus arise from?

Answer 23

L1 - L2 and their intervertebral discs

Question 24

What are the three openings of the diaphragm?

Answer 24

The caval opening
The oesophegeal hiatus
The aortic hiatus

Question 25

Where is the caval opening located?

Answer 25

T8

Question 26

Where is the oesophagus hiatus?

Answer 26

T10

Question 27

Where is the aortic hiatus located?

Answer 27

T12

Question 28

What does the vena caval opening pass through?

Answer 28

The central tendon

Question 29

What does the vena caval opening transmit?

Answer 29

inferior vena cava and the right phrenic nerve.

Question 30

What does the oesophageal opening pass through

Answer 30

muscular sling of the right crus

Question 31

What does the oesophageal opening pass through?

Answer 31

It passes through the oesophagus and the vagus nerve.

Question 32

What does the aortic hiatus pass through?

Answer 32

between the right and left crus

Question 33

What does the aortic hiatus pass though?

Answer 33

aorta, the azygous vein, the hemiazygous vein and the thoracic duct.

Question 34

What innervates the diaphragm?

Answer 34

The phrenic nerve

Question 35

How many phrenic nerves are there?

Answer 35

2

Question 36

Where do the phrenic nerves pass through?

Answer 36

In front of the hilium on the sides of the heart.

Question 37

Is the phrenic nerve a mixed nerve?

Answer 37

Yes (both motor and sensory)

Question 38

What are the roots of the phranic nerve?

Answer 38

C3 - C5

Question 39

What are the sensory functions of the phranic nerve?

Answer 39

Supply the central part of the diaphragm

Question 40

What are the innervations of peripheral portions of the diaphragm?

Answer 40

Sensory fibres of intercostal nerves T7-T12

Question 41

What will happen if the right phrenic nerve is damaged?

Answer 41

Right dome will be paralysed and it goes upwards instead of downwards becasue the active part will contract and go down and will push the abdominal viscera to the other side so the paralysed part will go higher instead of lower.