The Thorax

Question 1

Identify which ribs are true ribs, false ribs and floating ribs

Answer 1

Ribs 1-7 are true ribs
Ribs 8-10 are false ribs
Ribs 11 and 12 are floating ribs

Question 2

What is the structure of the ribs?

Answer 2

There are 3 sections: Head, Neck and Body

Question 3

Describe the head of a rib

Answer 3

It is wedge shaped, and has 2 articulating facets (except for ribs 1, 10, 11 and 12) to articulate with its corresponding vertebrae and the vertebrae above

Question 4

Describe the neck of a rib

Answer 4

It has a tubercle which articulates with the transverse process of the vertebrae

Question 5

Describe the body of a rib

Answer 5

It is flat and curved, its internal side has a groove on its inferior side–> the costal groove

Question 6

What are the special features of Rib 1

Answer 6

1. It has only 1 articulating facet
2. It forms a primary cartilaginous joint with the sternum
3. It has a groove for the Subclavian vein anterior to the tubercle
4. It has a groove for the Subclavian Artery posterior to the tubercle
5. The Scalene Tubercle on the upper surface is attached to the scalenus anterior muscle

Question 7

What kind of joint joins the ribs and the vertebrae?

Answer 7

Synovial joints

Question 8

What kind of joins are between Costal Cartilages 2-7 and the Sternum?

Answer 8

Synovial Joints

Question 9

What kind of joins are between Costal Cartilages 8-10 and the Sternum?

Answer 9

They do not articulate directly with the sternum- They have synovial joints with the costal cartilages immediately above them

Question 10

What are the 3 sections of the Sternum?

Answer 10

Manubrium, Body and Xyphoid Process

Question 11

Where is the Xyphoid Process?

Answer 11

T9

Question 12

Where is the Manubriosternal Joint and what is the other name for it?

Answer 12

Level T4, also known as the “Angle of Louis”

Question 13

What are the parts of Thoracic Vertebrae?

Answer 13

1. Spinous Process
2. Transverse Processes
3. Pedicle (joins body to transverse process)
4. Lamina (joins transverse process to the spinous process)
5. Superior Articular Process (forms synovial joints with vertebrae above)

Question 14

What kind of join is between 2 vertebrae?

Answer 14

Secondary Cartilaginous Joint

Question 15

What is a slipped disc?

Answer 15

When there is a tear in the fibrous ring surrounding the articulating disc, causing the disc to ‘pop out’

Question 16

What are the movements of the ribs that aid with breathing?

Answer 16

Pump handle movement and Bucket handle movement

Question 17

Describe Pump Handle movement

Answer 17

In inspiration, the sternum moves outwards and upwards, pulling the ribs with it, increasing the anterior space in the thoracic cavity

Question 18

Describe Bucket Handle movement

Answer 18

In inspiration, the lower ribs elevate laterally, increasing the transverse space in the thoracic cavity

Question 19

What are the intercostal muscles?

Answer 19

1. External
2. Internal
3. Innermost

Question 20

Describe the External Intercostal Muscles (Direction)

Answer 20

Passes downwards diagonally and medially

Question 21

Describe the internal and innermost intercostal muscles

Answer 21

Passes downwards diagonally and laterally

Question 22

What are the muscles of respiration?

Answer 22

1. Diaphragm
2. External Intercostals
3. Accessory muscles: Abdominal muscles, sternocleidomastoid and pectoral muscles

Question 23

What is the neuromuscular supply to the intercostal muscles?

Answer 23

Neurovascular bundles in the costal groove, consisting of Vein, Artery and Nerve

Question 24

What is the Arterial Supply of the Thorax?

Answer 24

1. Posterior Intercostal Arteries
2. Internal Thoracic Arteries
3. Axillary Artery

Question 25

What is the venous drainage of the thorax anteriorly?

Answer 25

Anterior Intercostal Veins--> Internal Thoracic Veins--> Subclavian Vein--> Brachiocephalic Vein--> Superior Vena Cava

Question 26

What is the venous drainage of the thorax posteriorly?

Answer 26

Posterior Intercostal veins--> Azygous system--> Superior Vena Cava

Question 27

Where does the azygous vein cross into the Superior Vena Cava?

Answer 27

Level T4

Question 28

Where is the Accessory Hemizygous Vein and where does it cross into the Azygous Vein?

Answer 28

It is on the left side from levels T4-T8 and it join back into the Azygous Vein at T8

Question 29

Where are the Hemiazygous Veins and where does it cross into the Azygous Vein?

Answer 29

It is on the left side from T9-T12, and it joins back into the Azygous Vein at T9

Question 30

What is the Nervous Supply of the Thorax?

Answer 30

1. Intercostal Nerves | 2. Phrenic Nerves

Question 31

Where does the Phrenic Nerve Originate?

Answer 31

Roots C3,4,5

Question 32

What are the subdivisions of the mediastinum?

Answer 32

Anterior, Middle, Posterior, Superior and Inferior

Question 33

What is a Pneumothorax?

Answer 33

When there is air between the visceral and partial pleura of the lung

Question 34

What is a Pleural Effusion?

Answer 34

When there is fluid in the pleural space

Question 35

What is a Haemothorax?

Answer 35

When there is blood in the pleural space

Question 36

Where would you insert a chest drain?

Answer 36

4th/5th intercostal space just anterior to the mid-axillary line or the 2nd intercostal space along the mid-clavicular line