Thoracic wall

Question 1

Boundaries of thorax

Answer 1

Upper - Thoracic inlet (sup thoracic aperture) 5 cm ant- post and 10 cm transversely
T1 and first ribs
Lower - thoracic outlet (inferior thoracic aperature)
T12, ribs 7 to 12, xiphoid process

Question 2

What does the thorax contain?

Answer 2

• An external musculoskeletal cage

- An internal cavity

Question 3

Function of thoracic wall x 3

Answer 3

❑ Respiration 
- Intrinsic and extrinsic muscles
- Vital for lung health
❑ Protect organs
- Heart
- Lungs
❑ Supports the breast

Question 4

Differences male vs female

Answer 4

• Sternum is shorter in females
• Thoracic inlet is more oblique in females
• Suprasternal notch is level with T3 in females
• Suprasternal notch is level with T2 in males

Question 5

What is the anterior axillary fold formed by?

Answer 5

The lower border of the pectoralis major muscle

Question 6

What is the posterior axillary fold formed by?

Answer 6

The latissimus dorsi and teres major muscles.

Question 7

Axillary lines diagram

Answer 7

Question 8

Thoracic lines diagram

Answer 8

Question 9

Bone marrow biopsy

Answer 9

A hematopoietic tissue, meaning blood cells are produced in this site. To obtain a bone marrow biopsy, a large bore needle is introduced into the sternum and a sample is aspirated

Question 10

What is the first palpable vertebral spinous process?

Answer 10

C7 - vertebra prominens

Question 11

Where are ribs counted from?

Answer 11

Second rib

Question 12

What passes behind the manubrium?

Answer 12

The superior vena cava

Question 13

What is the manubriosternal junction / sternal angle [angle of Louis] ?

Answer 13

The point of junction with the second costal cartilage (T4 – T5)

Question 14

What is an important landmark for the anatomical end of ant thoracic cage?

Answer 14

Xiphoid process

Question 15

4 areas that are used for auscultating (listening to heart valves with a stethoscope)

Answer 15

• Aortic area: At the 2nd intercostal space to the right of the sternum
• Pulmonic area: At the 2nd intercostal space to the left of the sternum
• Tricuspid area: Over the lower-left sternal border
• Mitral area: Apex beat - Left 5th intercostal space at the midclavicular line

Question 16

Label

Answer 16

Question 17

Thoracic wall components

Answer 17

❑ Muscles and bones enclosing the thoracic cavity –a musculoskeletal wall
❑ Excludes the diaphragm
❑ 12 thoracic vertebrae – typical and atypical
❑ 12 pairs of ribs with costal cartilages
❑ The sternum
❑ Intercostal spaces
❑ Endothoracic fascia
❑ Parietal and visceral pleura

Question 18

Endothoracic fascia

Answer 18

Deep to the intercostal spaces and ribs, separating these structures from the underlying pleura. Outermost membrane of the thoracic cavity
o Contains variable amounts of fat
o Thickens over the top of each lung as Suprapleural (Sibson’s fascia) membrane attaches to the internal border of the first rib and the transverse processes of C7