Anatomy - Upper Respiratory Tract & Anterior Chest Wall Flashcards
What bones does the pectoralis major articulate with?
clavicle and sternum
What do the pectoralis minor attach to?
Part of scapula and then to the ribs
What are pectoralis major and minor known as?
Accessory respiratory muscles
What is the 1ary action of the pectoralis major and minor?
How do they contribute in times of respiratory distress?
On the upper limb
These muscles will contract to help elevate the thoracic cage during inspiration.
Where does the serratus anterior originate?
Muscle that originates on the surface of the 1st to 8th ribs at the side of the chest
What does the serratus anterior act to do?
Acts to pull the scapula towards the thorax.
As the external intercostals muscles approach anterior aspect, how do they change?
Lose muscle fibres and start to become membranous
Where is the intercostal neurovascular bundle found?
Between the internal and innermost intercostal muscles
Where does the intercostal neurovascular bundle sit?
In the costal groove
What is the order of the intercostal neurovascular bundle?
VAN - vein, artery, nerve (superior to inferior)
What does the intercostal nerve supply?
Supplies those intercostal muscles.
Also supplies the parietal pleura (lines thoracic cavity) which lies deep to intercostal muscles.
What does the intercostal vein drain?
Drains intercostal muscles of deoxygenated blood
What does the intercostal vein drain into?
Azygos system
Which arteries directly supply the thoracic wall?
- Posterior intercostal arteries
- Anterior intercostal arteries
- Internal thoracic arteries
Where does the internal thoracic artery originate from? (one on right and one on left)
Subclavian artery
What does the internal thoracic artery supply? (one on right and one on left)
intercostal muscles, skin and parietal pleura associated with the first 6 intercostal spaces.
Describe route of internal thoracic artery (left and right)
The arteries enter the thoracic cavity as they descend behind the clavicle and first costal cartilage. Upon entering the chest cavity, the vessel is crossed anteriorly by the phrenic nerve. It continues posteriorly to the first six costal cartilages, lateral to the sternum, and deep to the pectoralis major. The vessel passes behind the external intercostal membrane and internal intercostal muscles up to the level of the second or third costal cartilage. Beyond this level, it passes in front of the transversus thoracis muscles
What branches does the internal thoracic artery give off?
Mummy Swallowed Ancient Papyrus Scrolls’, which stands for:
Musculophrenic a. Superior epigastric a. Anterior intercostal a. Perforating a. Sternal a.
Which anterior intercostal arteries does the internal thoracic give off?
Upper 6 anterior intercostal arteries
What are each of the upper 9 intercostal spaces supplied by?
3 vessels; a single posterior intercostal artery and the two anterior intercostal arteries.
What are the 10th and 11th intercostal spaces supplied by?
The 10th and 11th intercostal spaces are supplied by the posterior intercostal arteries only
What is the source for the upper 6 anterior intercostal arteries?
Internal thoracic artery
How many posterior intercostal arteries are there?
11
Where does the 1st and 2nd posterior intercostal arteries originate from?
From the superior (supreme) intercostal artery, a branch of the costocervical trunk
Where does the 3rd to 11th posterior intercostal arteries arise from?
Directly from the thoracic aorta.
Is the thoracic aorta displaced towards the left or right of the vertebral column?
Left
Where are the subcostal arteries branches of?
direct branches of the thoracic aorta
What are the subcostal arteries analagous to?
They are analogous to the posterior intercostal artery, so if there was a 12th intercostal space, they would be the 12th intercostal arteries. Each subcostal artery gives the anterior and posterior branches that travel along with the subcostal space below the twelfth rib.
Where do the subcostal arteries travel?
accompanies the subcostal vein and nerve in the subcostal space
How many internal thoracic arteries are there?
Only a right and a left
What lies posteriorly to the nasal and oral cavity?
Pharynx
How does inspired air reach the paranasal sinuses?
Conchae creates meatuses (pathways) which open into paranasal sinuses
Which duct runs from the eye into the nasal cavity via the inferior meatus?
Nasolacrimal duct
Where does the auditory tube (Eustachian tube) run to/from?
runs from pharynx to the tympanic membrane (ear drum)
What is purpose of auditory tube?
How we equalise air pressure across tympanic membrane.
Where does nasopharynx run from/to?
Runs from posterior nasal cavity to uvula.
What separates the nasal and oral cavity? How does this change?
The palate separating the nasal and oral cavity starts off muscular but softens (‘soft palate’) as you move posteriorly.
What is importance of epiglottis?
Important in sealing off larynx (airway) during swallowing (not a complete seal so can still end up with foreign bodies in respiratory system).
What does the laryngopharynx continue inferiorly as?
The oesophagus
What is found anterior to the laryngopharynx?
Larynx which continues as trachea
How many pairs of anterior intercostal arteries are there?
9
Where do the first 6 anterior intercostal arteries arise from?
Internal thoracic artery
Where do the last 3 anterior intercostal arteries arise from?
from the musculophrenic arteries
