Axilla/Brachial Plexus

Question 1

borders of axilla

Answer 1

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

Question 2

contents of axilla

Answer 2

• fat and connective tissue
• axillary v and lymphatics (outside sheath)
• cutaneous nerves
• axillary sheath with axillary a. and brachial plexus

Question 3

5 principal groups of nodes in the axilla

Answer 3

• pectoral
• subscapular
• humeral
• central
• apical

Question 4

pectoral nodes receive lymph from ____ and most of ____

Answer 4

anterior thoracic wall; breast

Question 5

subscapular nodes receive lymph from ____ and ____ region

Answer 5

posterior thoracic wall; scapular

Question 6

humeral nodes receive lymph from ___ except for portion along the ____

Answer 6

upper limb; cephalic v.

Question 7

central nodes receive lymph from ____ to ____

Answer 7

pectoral, subscapular, and humeral nodes; apical nodes

Question 8

apical nodes receive lymph from ____ plus the ____ nodes

Answer 8

all other axillary nodes; proximal cephalic vein

Question 9

the axillary artery arises from the subclavian a. at the ____

Answer 9

lateral border of the 1st rib

Question 10

axillary a. gives rise to brachial a. at the ____

Answer 10

inferior border of the teres major m.

Question 11

1st part of axillary a. is between ___ and ____ and gives off ____

Answer 11

1st rib; pec minor m. ; superior thoracic a.

Question 12

2nd part of axillary a. is ___ to pec minor m. and gives off ____ and ____

Answer 12

deep; thoracoacromial a. ; lateral thoracic a.

Question 13

3rd part of axillary a. is between ___ and ____; gives off ____ and ____

Answer 13

pec minor; teres major; subscapular a.; anterior & posterior circumflex humeral aa.

Question 14

brachial plexus composed of ventral rami ____; supplies all UL mm. except ____

Answer 14

C5-T1; trapezius (inn by CN XI)

Question 15

structure of the brachial plexus

Answer 15

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

Question 16

the lateral cord contains ___ divisions from the upper and middle trunks, thus containing contributions from ____ rami

Answer 16

anterior; C5-C7

Question 17

the posterior cord contains ____ divisions of all the trunks, thus containing contributions from ____ rami

Answer 17

posterior; C5-T1

Question 18

the medial cord contains the ___ division of the lower trunk, thus containing contributions from ____ rami

Answer 18

anterior; C8-T1

Question 19

5 terminal branches of the brachial plexus

Answer 19

musculocutaneous (C5, C6, C7)
median (C5-T1)
axillary (C5 and C6)
radial (C5-T1)
ulnar (C8, T1)

Question 20

major nerve of the anterior arm

Answer 20

musculocutaneous n. (C5-C7)

Question 21

musculocutaneous n. is formed from the ___ cord and passes through _____ m. ; also enters ____ and ____ mm.

Answer 21

lateral; coracobrachialis; biceps brachii; brachialis

Question 22

what does musculocutaneous n. innervate?

Answer 22

coracobrachialis, biceps brachii, and half of brachialis m.

Question 23

median nerve (C5-T1) is formed from ___ and ____

Answer 23

half of the lateral cord; half of the medial cord

Question 24

the median n. is the major nerve of the ____ and passes ____ to arm muscles

Answer 24

anterior forearm; medial

Question 25

what does the median n. innervate?

Answer 25

most of the anterior forearm, 3 thenar eminence mm. and first 2 lumbricals in the hand

Question 26

the ulnar n. is formed from the ____ cord; runs behind the ____ and is the major n. of the ____

Answer 26

medial; medial epicondyle; hand

Question 27

what does the ulnar n. innervate?

Answer 27

most of the mm of the hand, flexor carpi ulnaris m., and the ulnar half of flexor digitorum profundus m. in the forearm

Question 28

the axillary n. (C5-C6) is formed from the ____ cord; circles behind the ___ in the _____

Answer 28

posterior; humerus; quadrangular space

Question 29

what does the axillary n. innervate?

Answer 29

deltoid and teres minor mm.

Question 30

the radial n. (C5-T1) is formed from the ____ cord; it passes posterior to the humerus in the ____ and within the ____

Answer 30

posterior; radial groove; triangular interval

Question 31

radial n. is the major n. of the ____ and ____

Answer 31

posterior arm; forearm

Question 32

what does the radial n. innervate?

Answer 32

all muscles in the posterior arm and forearm plus half of the brachialis m.

Question 33

other nerves of the brachial plexus are formed directly from ___, ____, and ____

Answer 33

rami; trunks; cords

Question 34

other nerves of the brachial plexus include: ____, ____, ____ and additional nn.

Answer 34

upper plexus nn; pectoral nn; lower plexus nn

Question 35

upper plexus includes branches from ____

Answer 35

C5-C7

Question 36

pectoral nn. are from ____

Answer 36

upper and lower trunks

Question 37

lower plexus nerves are from the ____ portions of all 3 trunks

Answer 37

posterior

Question 38

upper plexus nn. include:

Answer 38

dorsal scapular n. (C5) long thoracic n. (C5-C7) suprascapular n. (C5-C6)

Question 39

dorsal scapular n. innervates?

Answer 39

rhomboid and levator scapulae mm.

Question 40

long thoracic n. innervates?

Answer 40

serratus anterior m.

Question 41

suprascapular n. innervates?

Answer 41

supraspinatus and infraspinatus mm.

Question 42

pectoral nn. include:

Answer 42

lateral pectoral n. (C5-C7) | medial pectoral n. (C8-T1)

Question 43

lateral pectoral n. innervates?

Answer 43

pectoralis major m.

Question 44

medial pectoral n. innervates?

Answer 44

pectoralis major and minor mm.

Question 45

lower plexus nn. include:

Answer 45

upper subscapular n. (C5-C6) thoracodorsal n. (C6-C8) lower subscapular n. (C5-C6)

Question 46

upper subscapular n. innervates?

Answer 46

subscapularis m.

Question 47

thoracodorsal n. innervates?

Answer 47

latissimus dorsi m.

Question 48

lower subscapular n. innervates?

Answer 48

subscapularis and teres major mm.

Question 49

additional brachial plexus nn. include:

Answer 49

nerve to subclavius m. (C5-C6) medial brachial cutaneous n. (C8-T1) medial antibrachial cutaneous n. (C8-T1)

Question 50

nerve to subclavius innervates?

Answer 50

subclavius m.

Question 51

medial brachial cut. n. innervates?

Answer 51

sensory to medial arm

Question 52

medial antibrachial cut. n. innervates?

Answer 52

sensory to medial forearm