Week 1: Thoracic Anatomy Flashcards
Which are the true ribs?
1-7
Which are the false ribs?
8-10
Which are the floating ribs?
11-12
Which tissue do the thoracic cage and wall refer to respectively?
cage: skeletal wall: muscular
Which structures pass through the inferior thoracic aperture? Also think of the level of passage through the diaphragm
- oesophagus (T10 - level of passage through diaphragm) - aorta (T12 - level of passage through diaphragm) - inferior vena cava (T8 - level of passage through diaphragm) - thoracic duct - azygous vein - phrenic nerve
At what level are the oesophageal and aortic hiatus respectively?
T10 and T12
Name 4 functions of the thoracic cage
- protect throacic organs - protect abdominal organs - provide attachment for muscles - support the weight of the upper limbs
Name the components of the thoracic cage
- thoracic vertebrae - intervertebral discs - ribs - sternum - costal cartilages
What cartilage type makes up the costal cartilage?
hyaline
How many ribs are there in total?
12
In which ways does the thoracic cage expand (3)?
- Ribs elevate and flare out (transverse plane increase) - Sternum and distal ribs elevate and move anteriorly (sagittal plane) - Diaphragm contracts and moves inferiorly (coronal plane)
How does Boyle’s Law explain inspiration through an increase in the thoracic space
The increase in volume is inversely proportional to the air pressure. This means an increase in volume decreases the pressure and creates a negative pressure compared to atmospheric air. This negative pressure causes air to move into the lungs
To which structures does the diaphragm attach
Xiphoid process - Costal margin - Lateral floating ribs - T12 - Central tendon (insertion)
Which 3 main structures pass through the diaphragm?
- IVC (level T8) - oesophagus (Level T10) - aorta (Level T12)
What is the nervous spply of the diaphragm? (nerve+roots)
phrenic nerve via anterior rami of C3,4,5
Describe the external intercostal muscle (activity, fibre direction)
Fibres run inferio-medially - Active during inspiration