Pectoral Region and Brachial Plexus

Question 1

proximal attachment of pectoralis major

Answer 1

clavicular: medial clavicle
sternocostal: anterior sternum, superior 6 costal cartilages and external oblique aponeurosis

Question 2

distal attachment of pectoralis major

Answer 2

lateral lip of intertubercular sulcus of humerus

Question 3

inn. of pectoralis major

Answer 3

medial and lateral pectoral n, clavicular (C5-6), sternocostal (C7-T1)

Question 4

action of pectoralis major

Answer 4

adduct and medially rotate arm, draw scapula anteriorly and inferiorly
clavicular: flex arm
sternocostal: extend arm from flexed position

Question 5

proximal attachment of pectoralis minor

Answer 5

3-5th ribs near costal cartilages

Question 6

distal attachment of pectoralis minor

Answer 6

scapular and coracoid process

Question 7

inn. of pectoralis minor

Answer 7

medial pectoral n (C8-T1)

Question 8

action of pectoralis minor

Answer 8

draw scapula inferiorly and anteriorly against thoracic wall to stabilize it

Question 9

proximal attachment of serratus anterior

Answer 9

1st-9th ribs

Question 10

distal attachment of serratus anterior

Answer 10

vertebral border and inferior angle of scapula

Question 11

inn. of serratus anterior

Answer 11

long thoracic n (C5-C7)

Question 12

action of serratus anterior

Answer 12

protract scapula and hold against thoracic wall, rotate scapula upwards

Question 13

proximal attachment of subclavius

Answer 13

junction of rib 1 and its costal cartilage

Question 14

distal attachment of subclavius

Answer 14

inferior surface of middle clavicle

Question 15

inn. of subclavius

Answer 15

subclavian n (C5-C6)

Question 16

action of subclavius

Answer 16

anchor and depress scapula (via clavicle)

Question 17

proximal attachment triceps brachii

Answer 17

long head- infraglenoid tubercle of scapula
lateral- posterior arterial humerus proximal to radial groove
medial- posterior humerus distal to radial groove

Question 18

distal attachment triceps brachii

Answer 18

proximal olecranon process of ulna

Question 19

inn. of triceps brachii and anconeus

Answer 19

radial n

Question 20

action of triceps brachii

Answer 20

chief forearm extensor (long head resists humeral dislocation)

Question 21

anconeus proximal attachment

Answer 21

lateral epicondyle of humerus

Question 22

anconeus distal attachment

Answer 22

lateral olecranon and proximal ulna

Question 23

action of anconeus

Answer 23

assist triceps in forearm extension, stabilize elbow joint

Question 24

proximal attachment of biceps brachii

Answer 24

short head- scapular coracoid process
long head- supraglenoid tubercle of scapula

Question 25

distal attachment of biceps brachii

Answer 25

radial tuberosity and bicipital aponeurosis

Question 26

inn. of biceps brachii, coracobrachialis, and brachialis (anterior arm)

Answer 26

musculocutaneous n

Question 27

action of biceps brachii

Answer 27

supinates forearm, when supine* flexes forearm, assists arm (upper arm) flexion (long head)
short head resists shoulder dislocation

Question 28

proximal attachment of coracobrachialis

Answer 28

tip of coracoid process of scapula

Question 29

distal attachment of coracobrachialis

Answer 29

middle of medial humerus surface

Question 30

action of coracobrachialis

Answer 30

help flex and adduct arm (resists shoulder dislocation)

Question 31

proximal attachment of brachialis

Answer 31

distal 1/2 of anterior humerus

Question 32

distal attachment of brachialis

Answer 32

coronoid process and ulnar tuberosity

Question 33

action of brachialis

Answer 33

flex forearm in ALL positions*