Axilla & Brachial Plexus Flashcards
What is the axilla?
Pyramidal space
Inferior to shoulder, superior to armpit
Which structures form the walls of the axilla?
Medial = superolateral aspect of chest Anterior = Pectoralis major Posterior = Teres major
What are the roles of Pectoralis major?
Major muscle of climbing
Accessory muscle of inspiration
What is the axillary vein?
Continuation of brachial vein
Becomes axillary at lower border of Teres major
Where does the subclavian artery become the axillary artery?
Lateral border of first rib
Which nerve roots form the brachial plexus?
Anterior rami of C5-T1
From proximal to distal, what are the components of the brachial plexus?
Roots Trunks Divisions Cords Named Nerves
What are the trunks of the brachial plexus and their components?
Superior = C5 and C6 Middle = C7 Inferior = C8 and T1
What ar the divisions of the brachial plexus?
Each trunk divides into an anterior and posterior division
What are the cords of the brachial plexus and their components?
Medial = Anterior division of inferior trunk Lateral = Anterior divisions of superior and middle trunks Posterior = Posterior divisions of all three trunks
What are the named nerves of the brachial plexus and their components?
Ulnar nerve = medial cord Musculocutaneous nerve = lateral cord Axillary nerve = posterior cord Radial nerve = posterior cord Median nerve = medial and lateral cords
Where are the roots and trunks of the brachial plexus located?
Between anterior and middle scalene muscles
Where are the divisions of the brachial plexus located?
Immediately posterior to the subclavian vessels in the root of the neck
Where are the cords of the brachial plexus located?
Around the axillary artery (distal to first rib)
Where does the musculocutaneous nerve supply?
Anterior compartment of the arm
