Axillary Contents, Brachial Plexus Flashcards
Anterior boundary of the axillary region?
Pec. Major, Pec. Minor, Clavipectoral Fascia
Boundary marking the inlet of the axillary region?
1st rib, scapula clavicle
Boundary marking the medial axillary wall?
Serratus anterior, upper ribs
lateral boundary of the axillary region?
intertubercular groove
Posterior wall of the axillary region?
subscapularis, teres major, latissimus dorsi
Contents of the axillary region?
cords and terminal branches of the brachial plexus, axillary lymph nodes, axillary artery, fat
Location of 1st part of the axillary artery?
medial to where it runs under pec. minor.
Location of 2nd part of the axillary artery?
portion located under pec. minor
3rd part of the axillary artery?
lateral to pec. minor insertion on coracoid process
How many divisions are in each part of the axillary artery?
1st - 1 div.
2nd- 2 div.
3rd - 3 div.
Branches of the 1st part of the axillary artery?
supreme thoracic
Branches of the 2nd part of the axillary artery?
thoracoacromial a., lateral thoracic a.
Branches of the Thoracoaromial trunk?
Clavicular, acromial, deltoid, PECTORAL
Branches of the 3rd part of the axillary artery?
POSTERIOR CIRCUMFLEX HUMERAL, ANTERIOR CIRCUMFLEX HUMERAL ARTERY, SUBSCAPULAR ARTERY
Branches of the subscapular artery?
circumflex scapular artery, thoracodorsal artery
Why is the axillary space important?
its the gateway to the upper limb
What regions are linked by the axillary space?
Thoracic and neck region to arm
What encloses the contents of the axillary region?
The axillary sheath
Roots of the brachial plexus are also known as…
ventral primary rami
What compartment do the anterior divisions supply?
anterior
what compartment do the posterior divisions supply?
Posterior
The lateral cord contains fibers from what ventral rami?
C5-C7
The medial cord contains fibers from which ventral rami?
C8-T1
The posterior cord contains fibers from which ventral rami?
C5-T1
How are the nerve cords named in the brachial plexus?
After their position relative to axillary artery
The musculocutaneous nerve contains fibers from which two ventral rami?
C5, C6
The median nerve contains fibers from which ventral rami?
C5-T1
The ulnar nerve contains fibers from which ventral rami?
C8-T1
The median nerve contains nerve fibers from which ventral rami?
C5-T1
the axillary nerve contains fibers from which ventral rami?
C5, C6
The radial nerve contains fibers from which ventral rami?
C5-T1
Which nerves supply the anterior compartment of the upper limb?
Musculocutaneous, median, and ulnar
Which nerves supply the posterior compartments of the upper limb?
axillary and radial nerves
Which two nerves supply motor innervation to the the anteior compartment of the forarm and palm?
Median (C5-T1) and Ulnar (C8, T1) nerves
Which nerves supply motor innervation to the anterior compartment of the arm?
Musculocutaneous
The radial nerve exits to the posterior compartment through…
triangular interval
Where can the 3 subscapular nerves be located?
ventral surface of the subscapularis muscle
What is unique about the innervation of serratus anterior?
The long thoracic n. runs superficially along its surface
When might the long thoracic n. be compromised?
during surgery near the anterior chest wall (masectomy)
Indication that long thoracic nerve has been severed in mastectomy?
weakness when brushing hair
the superior (supreme) thoracic artery supplies which region(s)?
upper regions of the medial and anterior axillary walls.
Thoracoacromial trunk and its branches supply which muscles?
those on the anterior axillary wall.
The lateral thoracic artery supplies…
mammary gland and serratus anterior. (travels w/ long thoracic n.)
Posterior circumflex humeral artery
around surgical neck of humerus
anterior humeral circumflex artery
anterior travel around the surgical neck
Subscapular artery supplies…
the posterior axiallary wall with its two branches (circumflex scapular artery, thoracodorsal artery)
Where is blood supply to the upper limb susceptible to trauma?
Where is is subcutaneous or in a fixed position
Fracture of the 1st rib or anterior dislocation of the humeral head may cause trauma to the…
axillary artery
What does the dorsal scapular anastamoses refer to?
Collateral circulation around the scapula provided by circumflex scapular –> dorsal scapular, suprascapular arteries
Blockage of 1st or 2nd part of axillary will not completely cut off UE blood supply, why?
Blood from suprascapular and dorsal scapular arteries may flow back via circumflex scapular artery to re-enter axillary artery downstream
75% of lymph from breast tissue drains into…
axillary lymphatics
25% of breast tissue lymph travesls where?
to the parasternal lymph nodes to the other breast
