Intercostal Spaces Flashcards
(22 cards)
What is the order of the neurovascular bundle in the intercostal space?
Veins, Arteries, Nerves
This order is often abbreviated as VAN.
Where is the subcostalis muscle located?
Inner aspect of intercostal spaces posteriorly
What is the origin of the subcostalis muscle?
Inner surface of rib above, near its angle
What is the main action of the subcostalis muscle?
Depresses the ribs
Where does the sternocostalis muscle originate?
Lower 1/3 of posterior surface of body of sternum, posterior surface of xiphoid, and posterior surfaces of costal cartilages of 4th to 7th ribs
What is the insertion point of the sternocostalis muscle?
Costal cartilages of 2nd to 6th ribs
What is the action of the internal intercostal muscle?
Depresses the ribs, aids in forceful exhalation
True or False: The external intercostal muscles elevate the ribs during inspiration.
True
How are the intercostal muscles arranged?
In three sheets from outside inward: External Intercostal, Internal Intercostal, Innermost Intercostal
What fills the gaps between the ribs in the thoracic cage?
Intercostal muscles, intercostal nerves, vessels, and lymphatics
How many intercostal spaces are there on each side of the thoracic cage?
11 intercostal spaces
What is the clinical relevance of knowing the neurovascular structures of the intercostal spaces?
To avoid iatrogenic injury during medical procedures
What is the purpose of pleural drainage?
To remove air, blood, or fluid from the pleural cavity
What are the branches of the intercostal nerve responsible for?
Motor innervation to intercostal muscles and sensory innervation to parietal pleura and skin
What is the course of the intercostal nerve?
Runs in the costal groove and ends near the sternum
From which spinal nerves do the intercostal nerves originate?
Anterior rami of spinal nerves T1 – T11
Fill in the blank: The anterior primary ramus of the twelfth thoracic nerve forms the _______.
Subcostal nerve
What can cause an enlarged azygos vein?
Over hydration, pregnancy, constrictive pericarditis, superior vena cava obstruction, inferior vena cava obstruction, portal hypertension
Where do the upper two intercostal spaces receive blood supply from?
Superior intercostal artery, a branch of the costo-cervical trunk of the subclavian artery
What supplies the lower nine intercostal spaces?
Branches directly from the thoracic aorta
How do the anterior intercostal arteries connect with the posterior intercostal arteries?
Form anastomosis with the first two posterior intercostal arteries
What drains the anterior intercostal veins?
Internal thoracic and musculophrenic veins
