Axilla/Brachial Plexus Flashcards
borders of axilla
anterior wall = pectoralis major and minor
posterior wall = latissimus dorsi, teres major, and subscapularis
medial wall = serratus anterior
lateral wall = intertubercular sulcus of humerus
base = skin and fascia of armpit
contents of axilla
- fat and connective tissue
- axillary v and lymphatics (outside sheath)
- cutaneous nerves
- axillary sheath with axillary a. and brachial plexus
5 principal groups of nodes in the axilla
- pectoral
- subscapular
- humeral
- central
- apical
pectoral nodes receive lymph from ____ and most of ____
anterior thoracic wall; breast
subscapular nodes receive lymph from ____ and ____ region
posterior thoracic wall; scapular
humeral nodes receive lymph from ___ except for portion along the ____
upper limb; cephalic v.
central nodes receive lymph from ____ to ____
pectoral, subscapular, and humeral nodes; apical nodes
apical nodes receive lymph from ____ plus the ____ nodes
all other axillary nodes; proximal cephalic vein
the axillary artery arises from the subclavian a. at the ____
lateral border of the 1st rib
axillary a. gives rise to brachial a. at the ____
inferior border of the teres major m.
1st part of axillary a. is between ___ and ____ and gives off ____
1st rib; pec minor m. ; superior thoracic a.
2nd part of axillary a. is ___ to pec minor m. and gives off ____ and ____
deep; thoracoacromial a. ; lateral thoracic a.
3rd part of axillary a. is between ___ and ____; gives off ____ and ____
pec minor; teres major; subscapular a.; anterior & posterior circumflex humeral aa.
brachial plexus composed of ventral rami ____; supplies all UL mm. except ____
C5-T1; trapezius (inn by CN XI)
structure of the brachial plexus
rami (5) - emerge in upper neck trunks (3) - form in lower neck divisions (6) - split off behind clavicle cords (3)- form in axillary region branches (5)- split off in upper arm
the lateral cord contains ___ divisions from the upper and middle trunks, thus containing contributions from ____ rami
anterior; C5-C7
the posterior cord contains ____ divisions of all the trunks, thus containing contributions from ____ rami
posterior; C5-T1
the medial cord contains the ___ division of the lower trunk, thus containing contributions from ____ rami
anterior; C8-T1
5 terminal branches of the brachial plexus
musculocutaneous (C5, C6, C7) median (C5-T1) axillary (C5 and C6) radial (C5-T1) ulnar (C8, T1)
major nerve of the anterior arm
musculocutaneous n. (C5-C7)
musculocutaneous n. is formed from the ___ cord and passes through _____ m. ; also enters ____ and ____ mm.
lateral; coracobrachialis; biceps brachii; brachialis
what does musculocutaneous n. innervate?
coracobrachialis, biceps brachii, and half of brachialis m.
median nerve (C5-T1) is formed from ___ and ____
half of the lateral cord; half of the medial cord
the median n. is the major nerve of the ____ and passes ____ to arm muscles
anterior forearm; medial
what does the median n. innervate?
most of the anterior forearm, 3 thenar eminence mm. and first 2 lumbricals in the hand
the ulnar n. is formed from the ____ cord; runs behind the ____ and is the major n. of the ____
medial; medial epicondyle; hand
what does the ulnar n. innervate?
most of the mm of the hand, flexor carpi ulnaris m., and the ulnar half of flexor digitorum profundus m. in the forearm
the axillary n. (C5-C6) is formed from the ____ cord; circles behind the ___ in the _____
posterior; humerus; quadrangular space
what does the axillary n. innervate?
deltoid and teres minor mm.
the radial n. (C5-T1) is formed from the ____ cord; it passes posterior to the humerus in the ____ and within the ____
posterior; radial groove; triangular interval
radial n. is the major n. of the ____ and ____
posterior arm; forearm
what does the radial n. innervate?
all muscles in the posterior arm and forearm plus half of the brachialis m.
other nerves of the brachial plexus are formed directly from ___, ____, and ____
rami; trunks; cords
other nerves of the brachial plexus include: ____, ____, ____ and additional nn.
upper plexus nn; pectoral nn; lower plexus nn
upper plexus includes branches from ____
C5-C7
pectoral nn. are from ____
upper and lower trunks
lower plexus nerves are from the ____ portions of all 3 trunks
posterior
upper plexus nn. include:
dorsal scapular n. (C5)
long thoracic n. (C5-C7)
suprascapular n. (C5-C6)
dorsal scapular n. innervates?
rhomboid and levator scapulae mm.
long thoracic n. innervates?
serratus anterior m.
suprascapular n. innervates?
supraspinatus and infraspinatus mm.
pectoral nn. include:
lateral pectoral n. (C5-C7)
medial pectoral n. (C8-T1)
lateral pectoral n. innervates?
pectoralis major m.
medial pectoral n. innervates?
pectoralis major and minor mm.
lower plexus nn. include:
upper subscapular n. (C5-C6)
thoracodorsal n. (C6-C8)
lower subscapular n. (C5-C6)
upper subscapular n. innervates?
subscapularis m.
thoracodorsal n. innervates?
latissimus dorsi m.
lower subscapular n. innervates?
subscapularis and teres major mm.
additional brachial plexus nn. include:
nerve to subclavius m. (C5-C6)
medial brachial cutaneous n. (C8-T1)
medial antibrachial cutaneous n. (C8-T1)
nerve to subclavius innervates?
subclavius m.
medial brachial cut. n. innervates?
sensory to medial arm
medial antibrachial cut. n. innervates?
sensory to medial forearm
