Anterior Shoulder - Axilla and Arm Muscles

Question 1

Pectoralis Major Clavicular Head Origin

Answer 1

anterior surface of medial half of clavicle

Question 2

Pectoralis Major Insertion

Answer 2

Lateral lip of intertubercular sulcus of humerus

Question 3

Pectoralis Major Action

Answer 3

Adducts and medially rotates the humerus; draws scapula anteriorly and inferiorly

Question 4

Pectoralis Major Innervation

Answer 4

Lateral and medial pectoral nerves; clavicular head (C5,C6); sternocostal head (C7,C8,T1)

Question 5

Pectoralis Minor Origin

Answer 5

3rd-5th ribs near their costal cartilages

Question 6

Pectoralis Minor Insertion

Answer 6

Medial border and superior surface of coracoid process of scapula

Question 7

Pectoralis Minor Action

Answer 7

Stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall

Question 8

Pectoralis Minor Innervation

Answer 8

Medial Pectoral Nerve (C8,T1)

Question 9

Serratus Anterior Origin

Answer 9

External surfaces of lateral parts of 1st-8th ribs

Question 10

Serratus Anterior Insertion

Answer 10

Anterior surface of medial border of scapula

Question 11

Serratus Anterior Action

Answer 11

Protracts the scapula and holds it against thoracic wall; rotates scapula

Question 12

Serratus Anterior Innervation

Answer 12

Long thoracic nerve (C5,C6,C7)

Question 13

Subclavius Origin

Answer 13

Junction of 1st rib and its costal cartilage

Question 14

Subclavius Insertion

Answer 14

Inferior surface of middle third of clavicle

Question 15

Subclavius Action

Answer 15

Anchors and depresses clavicle

Question 16

Subclavius Innervation

Answer 16

Nerve to subclavius (C5,C6)

Question 17

Corachobrachialis Origin

Answer 17

Tip of coracoid process of scapula

Question 18

Corachobrachialis Insertion

Answer 18

Middle third of medial surface of humerus

Question 19

Corachobrachialis Action

Answer 19

Helps flex and adduct arm; resists dislocation of shoulder

Question 20

Corachobrachialis Innervation

Answer 20

Musculocutaneous nerve (C5,C6,C7)

Question 21

Biceps Brachii Long head Origin

Answer 21

Supraglenoid tubercle of scapula

Question 22

Biceps Brachii insertion

Answer 22

Tuberosity of radius and bicipital aponeurosis

Question 23

Biceps Brachii action

Answer 23

Supinates forearm and flexes forearm when it is supinated; short head resists should dislocation

Question 24

Biceps Brachii short head origin

Answer 24

tip of coracoid process of scapula

Question 25

Biceps brachii innervation

Answer 25

Musculocutaneous nerve (C5,C6,C7)

Question 26

Brachialis origin

Answer 26

Distal half of anterior surface of humerus

Question 27

Brachialis insertion

Answer 27

Coronoid process and tuberosity of ulna

Question 28

Brachialis Action

Answer 28

Flexes forearm in all positions

Question 29

Brachialis Innervation

Answer 29

Musculocutaneous nerve (C5,C6) and radial nerve (C5,C7)

Question 30

Triceps brachii medial head origin

Answer 30

Posterior surface of humerus, inferior to radial groove

Question 31

triceps brachii lateral head origin

Answer 31

Posterior surface of humerus, superior to radial groove

Question 32

triceps brachii long head origin

Answer 32

Infraglenoid tubercle of scapula

Question 33

triceps brachii insertion

Answer 33

Proximal end of olecranon of ulna and fascia of forearm

Question 34

triceps brachii action

Answer 34

Chief extensor of forearm; long head resists dislocation of the humerus; especially important during adduction

Question 35

triceps brachii innervation

Answer 35

Radial nerve (C6,C7,C8)

Question 36

Anconeus origin

Answer 36

Lateral epicondyle of humerus

Question 37

Anconeus insertion

Answer 37

Lateral surface of olecranon and superior part of posterior surface of ulna

Question 38

Anconeus Action

Answer 38

Assists triceps in extending forearm; stabilizes elbow joint; may abduct ulna during pronation

Question 39

Anconeus Innervation

Answer 39

Radial nerve (C7,C8,T1)

Question 40

Pectoralis Major Sternocostal Head Origin

Answer 40

anterior surface of sternum; superior six costal cartilages; aponeurosis of external oblique

Question 41

Pectoralis Major Sternocostal head action

Answer 41

Extends the humerus from the flexed position

Question 42

Pectoralis Major Clavicular Head action

Answer 42

Flexes humerus