Axilla

Question 1

What makes up the anterior wall of the axilla?

Answer 1

pectoralis major & minor

Question 2

What makes up the posterior wall of the axilla?

Answer 2

subscapularis, teres major, latissimus dorsi, long head of triceps

Question 3

What makes up the lateral wall of the axilla?

Answer 3

humerus

Question 4

What makes up the apex of the axilla?

Answer 4

1st rib, clavicle, superior scapula

Question 5

What makes up the base of the axilla?

Answer 5

fascia & skin

Question 6

What are the 1st section branches of the axillary artery?

Answer 6

superior thoracic artery (along pec minor)

Question 7

What does the superior thoracic artery supply?

Answer 7

1st-2nd intercostal spaces, subclavius, superior serratus anterior

Question 8

What are the 2nd section branches of the axillary artery?

Answer 8

thoracoacromial artery (trunk) - 4 branches->pectoral, deltoid, acromial, clavicular
lateral thoracic artery (travels with long thoracic nerve then descends lateral thoracic wall)

Question 9

What does the thoracoacromial artery (trunk) supply?

Answer 9

1st-2nd intercostal spaces

Question 10

What does the lateral thoracic artery supply?

Answer 10

pectoral muscles, serratus anterior, intercostal muscles, lateral breast

Question 11

What are the 3rd section branches of the axillary artery?

Answer 11

subscapular - 2 branches->circumflex scapular, thoracodorsal
anterior circumflex humeral artery
posterior circumflex humeral artery

Question 12

What does the subscapular artery supply?

Answer 12

circumflex scapular - posteriorly around lateral scapula border, dorsal scapula (anastomosis)
thoracodorsal - latissimus dorsi

Question 13

What is the difference between anterior and posterior circumflex humeral arteries? What do they supply?

Answer 13

anterior - smaller and passes laterally
posterior - larger and passes medially (with axillary nerve)

encircle humerus surgical neck
deltoid, teres major & minor, long head of triceps

Question 14

What makes up the scapular anastomosis? (Where are they from?)

Answer 14

dorsal scapular (subclavian), suprascapular (subclavian), circumflex scapular (subscapular), & intercostal branches

Question 15

Describe the brachial plexus

Answer 15

ventral rami of C5-T1, passes between anterior & middle scalenes, sensory & motor to upper limbs

Question 16

What are the terminal branches of the brachial plexus and what are their roots?

Answer 16

Musculocutaneous: lateral cord, C5-C7
Axillary: posterior cord, C5-C6
Radial: posterior cord, C5-T1
Median: lateral cord & medial cord, C6-T1
Ulnar: medial cord, C8-T1

Question 17

Where does the axillary nerve travel?

Answer 17

passes through quadrangular space with posterior circumflex artery (humerus surgical neck)

Question 18

What does the axillary nerve innervate?

Answer 18

deltoid & teres minor

Question 19

What is the sensory to the axillary nerve?

Answer 19

upper lateral arm

Question 20

Where does the musculocutaneous nerve travel?

Answer 20

pierces coracobracialis muscles & descends between brachialis & biceps

Question 21

What does the musculocutaneous nerve innervate?

Answer 21

anterior compartment of arm: biceps brachii, coracobrachialis, brachialis

Question 22

What is the sensory to the musculocutaneous nerve?

Answer 22

lateral forearm

Question 23

Where does the radial nerve travel?

Answer 23

posterior to humerus in medial groove with deep brachial artery (susceptible to humeral shaft fracture)

Question 24

What does the radial nerve innervate?

Answer 24

all posterior arm & forearm

Question 25

What is the sensory to the radial nerve?

Answer 25

posterior & inferolateral arm, posterior forearm, dorsum of hand

Question 26

Where does the median nerve travel?

Answer 26

adjacent to brachial artery (no branches to arm)

Question 27

What does the median nerve innervate?

Answer 27

forearm & hand (except flexor carpi ulnaris & half of flexor digitorum profundus)

Question 28

What is the sensory to the median nerve?

Answer 28

lateral palmar skin

Question 29

Where does the ulnar nerve travel?

Answer 29

descends medially in arm, passes posterior to medial epicondyle of the humerus

Question 30

What does the ulnar nerve innervate?

Answer 30

flexor carpi ulnaris, ulnar half of flexor digitorum profundus, most intrinsic muscles of the hand

Question 31

What is the sensory to the ulnar nerve?

Answer 31

medial 1.5 digits & medial aspect of hand

Question 32

What makes up the medial wall of the axilla?

Answer 32

upper rib cage-4th rib, intercostals, serratus anterior