arm muscles

Question 1

What are the muscles of the rotator cuff?

Answer 1

supraspinatus, subscapularis, infraspinatus, teres minor, & teres major

Question 2

What places a lot of strain on the rotator cuff and commonly causes injuries?

Answer 2

sports that involve throwing a ball

Question 3

What is the origin, insertion, and action of the supraspinatus?

Answer 3

O= supraspinous fossa of scapula, I= greater tubercle of humerus, A= abducts shoulder

Question 4

What is the origin, insertion, and action of the subscapularis?

Answer 4

O= subscapular fossa of scapula, I= lesser tubercle of humerus, A= medially rotates shoulder

Question 5

What is the origin, insertion, and action of the infraspinatus?

Answer 5

O= infraspinous fossa of scapula, I= greater tubercle of humerus, A= laterally rotates shoulder

Question 6

What is the origin, insertion, and action of the teres minor?

Answer 6

O= lateral border of scapula, I= greater tubercle of humerus, A= laterally rotates shoulder

Question 7

What is the origin, insertion, and action of the teres major?

Answer 7

O= inferior angle of scapula, I= intertubercle groove of humerus, A= extension, adduction, & medial rotation of the arm at shoulder joint

Question 8

What are the muscles of the upper extremity?

Answer 8

deltoid, biceps brachii, brachialis, coracobrachialis, brachioradialis, pronator teres, & triceps brachii

Question 9

What do upper arm muscles do?

Answer 9

cause movement at the elbow joint; they surround the humerus and insert on forearm

Question 10

What is the origin, insertion, and action of the deltoid?

Answer 10

O= scapular spine, acromion, & clavicle, I= deltoid tuberosity of humerus, A= abducts humerus/shoulder (prime mover)

Question 11

What are characteristics of the deltoid?

Answer 11

triangular shape; common site for injections; antagonist to latissimus dorsi

Question 12

What is the origin, insertion, and action of the biceps brachii?

Answer 12

O= coracoid process of scapula, I= radial tuberosity, A= prime mover of flexion of forearm/elbow; supinates forearm

Question 13

What is the biceps brachii?

Answer 13

2-headed muscle of anterior arm

Question 14

What is the origin, insertion, and action of the brachialis?

Answer 14

O= anterior surface of distal humerus, I= ulna, A= flexes forearm

Question 15

Where is the brachialis?

Answer 15

lies deep to biceps

Question 16

What is the origin, insertion, and action of the coracobrachialis?

Answer 16

O= coracoid process of scapula, I= medial shaft of humerus, A= adduct & flex shoulder

Question 17

What is the coracobrachialis?

Answer 17

antagonist to deltoid

Question 18

What is the origin, insertion, and action of the brachioradialis?

Answer 18

O= distal humerus; superior to lateral epicondyle, I= styloid process of radius, A= synergist to brachialis in forearm flexion

Question 19

What is the brachioradialis?

Answer 19

superficial muscle of lateral forearm

Question 20

What is the origin, insertion, and action of the pronator teres?

Answer 20

O= medial epicondyle of humerus, I= midshaft of radius, A= pronates forearm

Question 21

Where is the pronator teres?

Answer 21

anterior forearm superficial to brachialis

Question 22

What is the origin, insertion, and action of the triceps brachii?

Answer 22

O= glenoid cavity/posterior humerus, I= olecranon process of ulna, A= powerful prime mover of forearm extension

Question 23

What are characteristics of the triceps brachii?

Answer 23

antagonist of biceps; called “boxer’s muscle” because it delivers a straight arm knockout punch; 3-headed muscle of posterior arm

Question 24

What are the muscles of the forearm?

Answer 24

flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis, flexor digitorum profundus, extensor carpi radialis longus, extensor carpi ulnaris, & extensor digitorum

Question 25

What are characteristics of the forearm muscles?

Answer 25

insert on hand; have names that reflect their actions & location

Question 26

What is the origin, insertion, and action of the flexor carpi radialis?

Answer 26

O= medial epicondyle of humerus, I= 2nd & 3rd metacarpals, A= powerful wrist flexor; abducts hand

Question 27

Where is the flexor carpi radialis?

Answer 27

superficial; runs diagonal across forearm

Question 28

What is the origin, insertion, and action of the flexor carpi ulnaris?

Answer 28

O= distal humerus & posterior ulna, I= 5th metacarpal & carpals, A= powerful wrist flexor; adducts hand

Question 29

Where is the flexor carpi ulnaris?

Answer 29

superficial; medial to flexor carpi radialis

Question 30

What is the origin, insertion and action of the flexor digitorum superficialis & profundus?

Answer 30

O= distal humerus, ulna, & radius, I= middle phalanges of 2nd-5th fingers, A= flexes wrist & middle phalanges

Question 31

What is the origin, insertion and action of the extensor carpi radialis longus?

Answer 31

O= lateral humerus, I= 2nd & 3rd metacarpals, A= extends & abducts wrist

Question 32

Where is the extensor carpi radialis longus?

Answer 32

superficial; runs parallel with brachioradialis

Question 33

What is the origin, insertion and action of the extensor carpi ulnaris?

Answer 33

O= lateral epicondyle of humerus, I= 5th metacarpal, A= extends & adducts wrist

Question 34

Where is the extensor carpi ulnaris?

Answer 34

superficial; medial & posterior forearm

Question 35

What is the origin, insertion and action of the extensor digitorum?

Answer 35

O= lateral epicondyle of humerus, I= distal phalanges of 2nd-5th fingers, A= prime mover of finger extension; extends wrist; abducts fingers

Question 36

Where is the extensor digitorum?

Answer 36

superficial; lies between extensor carpi radialis & extensor carpi ulnaris