02.1 Lower Respiratory Tract - Anatomy

Question 1

What are the true ribs and why are they true ribs?

Answer 1

1-7

Connected by costal cartilage to sternum

Question 2

How are ribs 8-12 connected?

Answer 2

8-10 connected to costal cartilage above

11,12 are floating ribs with their ends free in the abdominal muscles

Question 3

Which ribs are typical?

Answer 3

3-9

Question 4

What are the features of a typical rib?

Answer 4

Shaft
Costal groove on inferior surface
Articulating process for the transverse process
Neck
Head
2 Articulate facets, for corresponding vertebrae and the one above

Question 5

Why is rib 1 considered atypical?

Answer 5

Rib 1 is short, broad and the most curved

It has a single articular facet

Question 6

Why is rib 2 considered atypical?

Answer 6

Poorly marked costal groove

Question 7

Why are ribs 11-12 considered atypical?

Answer 7

Single facet
No tubercle
Floating

Question 8

What are the three intercostal muscles in each intercostal space?

Answer 8

External
Internal
Innermost

Question 9

What direction do the external intercostal muscle fibres run?

Answer 9

Inferiorly and anteriorly

Question 10

What does contraction of the external intercostal muscles do?

Answer 10

Elevates the ribs.

Elevating upper ribs increases AP diameter.
Elevation of lower ribs increases lateral diameter.

Question 11

What is the role of the internal and innermost intercostal muscles?

Answer 11

To depress the ribs during forced expiration.

Reduces AP and lateral diameters of the chest.

Question 12

Where does each rib’s neurovascular bundle run?

Answer 12

In the costal groove of each rib

Question 13

What nerves are in the neurovascular bundle, where do they run and what do they supply?

Answer 13

Anterior rami of thoracic spinal nerves, T1-T12

Between internal and innermost intercostal muscles

Supply the intercostal muscles, parietal pleura and overlying skin

Question 14

What arteries supply the intercostal muscles?

Answer 14

Anterior and posterior intercostal arteries.

Question 15

How many arteries are in each intercostal space?

Answer 15

1x posterior artery from the thoracic aorta

2x anterior artery from the internal thoracic artery

Question 16

What is the venous drainage of the intercostal spaces?

Answer 16

Primarily into the azygos system.

Some drainage into the internal thoracic vein.

Question 17

What makes up the azygos system?

Answer 17

Azygos vein - Right aide

Hemiazygos vein and accessory hemiazygos vein - Left side

Question 18

What nerve supplies the diaphragm?

Answer 18

Phrenic nerve (C3,C4,C5)

Question 19

At what level is the opening for the vena cava in the diaphragm?

Answer 19

T8

Question 20

At what level is the opening for the oesophagus in the diaphragm?

Answer 20

T10

Question 21

At what level is the opening for the aorta in the diaphragm?

Answer 21

T12

Question 22

What is the level of the diaphragm domes during expiration?

Answer 22

Right - behind 5th rib MCL

Left - 5th ICS, MCL

Question 23

What is the costodiaphragmatic recess?

Answer 23

The pleura lined gutters that the lungs don’t fill.

Question 24

What are the borders of the trachea?

Answer 24

Lower border of cricoid cartilage to the carina

Question 25

What are the most inferior points of the pleura in terms of body markings?

Answer 25

8th rib, mid clavicular line 10th rib, mid axillary line 12th rib, in the scapular line

Question 26

What are the inferior limits of the lungs in terms of body markings?

Answer 26

6th rib MCL 8th rib Mid axillary line 10th rib Scapular line

Question 27

Which bronchi is stuff more likely to get stuck in and why?

Answer 27

Right bronchi as it is shorter, wider and more vertical

Question 28

What can an apical lung tumour involve?

Answer 28

Brachial plexus Subclavian vessels Sympathetic trunk

Question 29

What structures can be found in the superior mediastinum?

Answer 29

``` Superior vena cava Brachiocephalic veins Arch of aorta Trachea Oesophagus Thoracic duct Thymus Vagus nerve Left recurrent laryngeal nerve Phrenic nerve ```

Question 30

What can be found in the middle mediastinum?

Answer 30

``` Pericardium Heart Roots of the great vessels Azygos vein Main bronchi ```

Question 31

What can be found in the posterior mediastinum?

Answer 31

``` Oesophagus Thoracic aorta Azygos and hemiazygos veins Sympathetic trunks Vagus nerve Splanchnic nerves ```

Question 32

What are the three parts of the sternum?

Answer 32

Manubrium Body Xiphoid process