2.6 Axilla Flashcards
What is the lateral boundary of the axilla?
intertubercular groove of the humorous
What is the medial boundary of the axilla?
ribs, intercostal muscles and serrates anterior
What is the posterior boundary of the axilla?
subscapularis, latissimus dorsi, teres major
What is inclosed in the axillary sheath?
axillary vessels, axillary lymph nodes, and brachial plexus
Where does the transition between subclavian and axillary arteries begin?
lateral edge of the 1st rib
Axillary artery becomes the brachial artery as it passes the …
lower border of teres major muscle
The 1st segment of the axillary artery is … to the pectorals minor m.
proximal
The 2nd segment of the axillary artery is … to the pectorals minor m.
under (deep)
The 3rd segment of the axillary artery is … to the pectorals minor m.
lateral
What is the branch of the 1st segment of the axillary artery?
superior thoracic a.
Superior thoracic a. supplies muscles in…
the 1st two intercostal spaces
What are the 2 branches of the 2nd segment of the axillary artery?
thoracoacromial a (acromial, deltoid, pectoral) and lateral thoracic a.
What are the 3 branches of the 3rd segment of the axillary artery?
subscapular a (circumflex scapular a. and thoracodorsal a), post. humeral circumflex a. and ant. humeral circumflex
Where is the axillary vein in relation to the axillary artery?
superficial
The axillary vein is formed by the union of what 2 veins?
basilic and brachial vv.
The cephalic v lies in the deltopectoral groove and pierces the clavipectoral fascia to drain into the …
axillary v.
Deep lymphatics accompany the deep veins and terminate in the …
humeral (lateral) axillary lymph nodes
Superficial lymphatics enter in to what …
cubital lymph nodes or humeral (lateral) axillary lymph nodes
superficial lymphatics of accompanying the cephalic vein drain to the …
apical axillary lymph nodes
Lymphatics from the anterior chest wall and breast drain into which axillary lymph nodes?
pectoral (anterior) axillary lymph nodes
Lymphatics from the upper back and shoulder drain into which axillary lymph nodes?
subscapular (posterior) axillary lymph nodes
inflammation of axillary lymph nodes may cause pain as in …
lymphangitis
Following resection of metastatic nodes severe… may result due to lack of appropriate lymphatic return in upper limb
lymphedema
The brachial plexus is a network of nerves supplying what innervation to the upper extremity?
somatic sensory, somatic motor, and sympathetic
The brachial plexus is formed by the union of …
ventral primary rami of C5-T1
Roots are the ventral rami emerging from the spinal cord and located between what muscles?
anterior and middle scalene mm.
What are the 2 nerves coming of the roots of the brachial plexus?
dorsal scapular n. and long thoracic n.
What is the path of innervation of the dorsal scapular n?
C5 to rhomboid muscles and elevator scapulae m.
What is the path of innervation of the long thoracic n?
C5-C7 to serrates ant. m.
What are the named branches of the Superior Trunk?
suprascapular n and nerve to subclavius
What Roots form the superior trunk?
C5 and C6 roots
What is the path of innervation of the suprascapular n?
C5 and C6 to supraspinatus and infraspinatus mm
What is the path of innervation of the nerve to subclavius?
C5 to subclavius m
What root(s) form the middle trunk?
C7 root
What root(s) form the inferior trunk?
C8 and T1 roots
Each Trunk divides into anterior and posterior Divisions, located …, which unite to form Cords
posterior to the clavicle
The Medial Cord is formed by …division of … trunk; 5 named branches
anterior division of the inferior trunk
What are the 5 named branches of the Medial Cord?
medial pectoral n, medial brachial cutaneous n, medial ante brachial cutaneous n, ulnar n, and median n
What is the path of innervation of the medial pectoral n?
C5-T1 to pectoral m
What is the path of innervation of the medial brachial cutaneous n?
C8-T1 SENSORY to medial side of arm
What is the path of innervation of the medial ante brachial cutaneous n?
C8-T1 SENSORY to medial side of forearm
What is the path of innervation of the ulnar n?
C7-T1 hand innervation
What is the path of innervation of the median n?
C5-T1 MOTOR innervation to hand flexors
What forms the Posterior Cord?
posterior divisions of ALL trunks
What are the 5 named branches of the Posterior Cord?
upper subscapular n, thoracodorsal n (middle subscapular n), lower subscapular n, axillary n, and radial n
What is the path of innervation of the upper subscapular n?
C5-C6 to upper portion of subscapularis m
What is the path of innervation of the thoracodorsal n (middle subscapular n)?
C7-C8 to latissimus dorsi m
What is the path of innervation of the lower subscapular n?
C5-C6 to lower portion of subscapularis m
What is the path of innervation of the axillary n?
C5-C6 to deltoid and teres minor mm and sensory to lateral upper arm
What is the path of innervation of the radial n?
C5-T1 to brachial and antebrachial mm; hand extensors
What forms the Lateral Cord?
anterior divisions of superior and middle trunks
What are the 2 named branches of the Lateral Cord?
Lateral pectoral n and musculocutaneous n
What is the path of innervation of the lateral pectoral n?
C5-C7 to pectoralis major m
What is the path of innervation of the musculocutaneous n?
C5-C7 to coracobrachialis, biceps brachii, and brachial mm
What are the 5 terminal portions making major branches?
Musculocutaneous n, median n, axillary n, radial n, ulnar n.
Injuries to the superior part of the plexus (C5-C6) result in …
shoulder/arm paralysis (Erb-Duchenne palsy)
Erb-Duchenne palsy (shoulder/arm paralysis) yields the upper limb with …
an adducted shoulder, medially rotated arm and extended elbow
Injuries to the inferior part of the plexus (C8-T1) results in …
forearm/hand paralysis (Klumpke paralysis/claw hand)
