1.2 Shoulder and Axilla

Question 1

What artery branches off the 1st part of the axillary artery?

Answer 1

superior thoracic artery

Question 2

What 2 arteries branch off the 2nd part of the axillary artery?

Answer 2

thoracoacromial artery, lateral thoracic artery

Question 3

What 3 arteries branch off the 3rd part of the axillary artery?

Answer 3

subscapular artery, anterior circumflex humeral artery, posterior circumflex humeral artery

Question 4

artery that supplies muscles in the 1st and 2nd rib intercostals, space and serratus anterior, branches off 1st part of axillary artery

Answer 4

superior thoracic artery

Question 5

short, wide trunk deep to clavicular head of pectoralis minor, divides into 4 branches, comes off 2nd part of axillary artery

Answer 5

thoracoacromial artery

Question 6

supplies pectoral muscles, axillary lymph nodes, and breast*** (important blood supply to lateral part of mammary gland in women)

Answer 6

lateral thoracic artery

Question 7

largest branch of axillary artery, divides into circumflex scapular and thoracodorsal

Answer 7

subscapular artery

Question 8

anterior and posterior, branch off third part of axillary artery, supplies shoulder muscles (deltoid, teres major and minor, long head of triceps)

Answer 8

circumflex humeral arteries

Question 9

receives directly or indirectly blood from thoracoepigrastric vein, which collects blood from the superficial veins of the inguinal region, blood can bypass when IVC is blocked

Answer 9

axillary vein

Question 10

two nerves vulnerable during axillary lymph node dissection

Answer 10

long thoracic nerve, thoracodorsal nerve

Question 11

• adducts and medially rotates humerus
• clavicle head flexes and sternocostal head adducts/medially rotates humerus
• forms most of anterior wall of axilla
• forms deltopectoral groove with the deltoid muscle, cephalic vein runs in this groove

Answer 11

pectoralis major

Question 12

origin: clavicular head and sternocostal head
insertion: lateral lip of intertubercular groove of humerus
- adducts and medially rotates humerus, flex clavicle

Answer 12

pectoralis major

Question 13

• origin: coracoid process of scapula

- inserts: ribs 3,4,5

Answer 13

pectoralis minor

Question 14

• fixes scapula to thoracic wall

- stretches arm forward, helps with inspiration

Answer 14

pectoralis minor

Question 15

• rotates the inferior angle of the scapula (combing hair)
• holds scapula against thoracic wall (doing pushups)
• forms medial wall of axilla
• protracts the scapula, when punching or reaching anteriorly

Answer 15

serratus anterior

Question 16

origin: external surface of ribs 1-8
insertion: anterior surface and medial border of scapula

Answer 16

serratus anterior

Question 17

injury to this nerve will paralyze the serratus anterior, give a winged scapula appearance

Answer 17

long thoracic nerve

Question 18

• origin: superior nuchal line, C7, T12

- insertion: acromion, spine of scapula

Answer 18

trapezius

Question 19

-elevates scapula, retracts scapula, depresses scapula and lowers shoulder

Answer 19

trapezius

Question 20

innervated by spinal accessory nerve Cranial Nerve XI

Answer 20

trapezius

Question 21

• extends, adducts, and medially rotates the humerus

- brings body toward arms when climbing

Answer 21

latissumus dorsi

Question 22

innervated by thoracodorsal nerve

Answer 22

latissimus dorsi

Question 23

• origin: T7, thoracolumbar fascia, iliac crest

- insertion: intertubercular groove

Answer 23

latissimus dorsi

Question 24

If this nerve is injured there is no counter force for shoulder when pushed up by crutch, can’t climb

Answer 24

latissimus dorsi

Question 25

- origin: transverse process of C1-C4 | - insertion: medial border superior part of scapula

Answer 25

levator scapulae

Question 26

what muscles are innervated by dorsal scapular nerve?

Answer 26

levator scapulae, rhomboids

Question 27

- origin: C7, T1, T2, T3, T4, T5 | - insertion: medial borders of scapulae

Answer 27

rhomboids

Question 28

- origin: acromion, spine of scapula, clavicle | - insertion: deltoid tuberosity

Answer 28

deltoid

Question 29

- abductor (inital 15 degrees by suprspinatus) | - flexion and extension

Answer 29

deltoid

Question 30

innervated by axillary nerve

Answer 30

deltoid

Question 31

origin: inferior angle of scapula insertion: medial lip of intertubercular groove

Answer 31

teres major

Question 32

- stabilizes humeral head, counteracts deltoid during abduction of the arm - adduction and medial rotation of humerus

Answer 32

teres major

Question 33

What artery exits the triangular space b/w teres major and long head of triceps?

Answer 33

circumflex scapular artery

Question 34

What artery and nerve exit the quadrangular space b/w teres major and long head of triceps?

Answer 34

posterior circumflex humeral artery, axillary nerve

Question 35

rotator cuff muscles?

Answer 35

supraspinatus, infraspinatus, teres minor, subscapularis

Question 36

origin: lesser tubercle and greater tubercle | - stabilize shoulder joint

Answer 36

rotator cuff

Question 37

helps with initial 15 degrees of abduction of arm

Answer 37

supraspinatus

Question 38

small viscous fluid filled sac lined by synovial membrane

Answer 38

subacromial/subdeltoid bursa