Muscles of forearm ( posterior compartment)

Question 1

Origin of brachioradialis muscle

Answer 1

• Proximal part of the lateral supraepicondylar ridge of the humerus
  
  • Adjacent intermuscular septum

Question 2

Insertion of brachioradialis muscle

Answer 2

Lateral surface of distal end of radius

Question 3

Action of brachioradialis muscle

Answer 3

Accessory flexor of elbow joint when forearm is midpronated

Question 4

Innervation of brachioradialis muscle

Answer 4

Radial nerve

Question 5

Origin of extensor carpi radialis longus muscle

Answer 5

Lateral supraepicondylar ridge of the humerus

Question 6

Insertion of extensor carpi radialis longus muscle

Answer 6

Dorsal surface of base of the 2nd metacarpal

Question 7

Action of extensor carpi radialis longus muscle

Answer 7

Extends and abducts at the wrist joint

Question 8

Innervation of extensor carpi radialis longus muscle

Answer 8

Radial nerve

Question 9

Origin of extensor carpi radialis brevis muscle

Answer 9

Lateral epicondyle of humerus and adjacent intermuscular septum

Question 10

Insertion of extensor carpi radialis brevis muscle

Answer 10

Dorsal surface of base of 2nd and 3rd metacarpals

Question 11

Action of extensor carpi radialis brevis muscle

Answer 11

Extends and abducts at the wrist joint

Question 12

Innervation of extensor carpi radialis brevis muscle

Answer 12

Deep branch of the radial nerve

Question 13

Origin of extensor digitorum muscle

Answer 13

• Lateral epicondyle of humerus
  
  • Adjacent intermuscular septum and deep fascia

Question 14

Insertion of extensor digitorum muscle

Answer 14

Inserts via extensor hoods of medial 4 digits

Question 15

Action of extensor digitorum muscle

Answer 15

Extends medial 4 digits

Question 16

Innervation of extensor digitorum muscle

Answer 16

Posterior interosseous nerve from radial nerve

Question 17

Origin of extensor digit minimi muscle

Answer 17

• Lateral epicondyle of the humerus
  
  • Adjacent intermuscular septum

Question 18

Insertion of extensor digit minimi muscle

Answer 18

Extensor hood of the little finger

Question 19

Action of extensor digit minimi muscle

Answer 19

Extension of the little finger

Question 20

Innervation of extensor digit minimi muscle

Answer 20

Posterior interosseous nerve from radial nerve

Question 21

Origin of extensor carpi radialis muscle

Answer 21

Lateral epicondyle of the humerus and posterior border of ulna

Question 22

Insertion of extensor carpi radialis muscle

Answer 22

Tubercle on the base of the medial side of the 5th metacarpal

Question 23

Action of extensor carpi radialis muscle

Answer 23

Extends and adducts at the wrist joint

Question 24

Innervation of extensor carpi radialis muscle

Answer 24

Posterior interosseous nerve from radial nerve

Question 25

Origin of anconeus muscle

Answer 25

Lateral epicondyle of the humerus

Question 26

Insertion of anconeus muscle

Answer 26

Olecranon and proximal posterior surface of ulna

Question 27

Action of anconeus muscle

Answer 27

Abducts the ulna during pronation

Question 28

Innervation of anconeus muscle

Answer 28

Radial nerve

Question 29

Origin of supinator muscle

Answer 29

• Superficial layer
  
  • Humeral lateral epicondyle, radial collateral and annular ligament
  • Deep layer at the supinator crest of the ulna

Question 30

Insertion of supinator muscle

Answer 30

Lateral surface of the radius

Question 31

Action of supinator muscle

Answer 31

Supination

Question 32

Innervation of supinator muscle

Answer 32

Posterior interosseous nerve from radial nerve

Question 33

Origin of extensor indicis muscle

Answer 33

• Posterior surface of the ulna
  
  • Adjacent interosseous membrane

Question 34

Insertion of extensor indicis muscle

Answer 34

Extensor hood of the index finger

Question 35

Action of extensor indicis muscle

Answer 35

Extends the index finger

Question 36

Innervation of extensor indicis muscle

Answer 36

Posterior interosseous nerve from radial nerve

Question 37

Origin of extensor pollicis longus muscle

Answer 37

• Posterior surfaces of the ulna
  
  • Adjacent interosseous membrane

Question 38

Insertion of extensor pollicis longus muscle

Answer 38

Dorsal surface of base of proximal phalanx of the thumb

Question 39

Action of extensor pollicis longus muscle

Answer 39

Extends interphalangeal joint of the thumb

Question 40

Innervation of extensor pollicis longus muscle

Answer 40

Posterior interosseous nerve from radial nerve

Question 41

Origin of extensor pollicis brevis muscle

Answer 41

• Posterior surfaces of the radius
  
  • Adjacent interosseous membrane

Question 42

Insertion of extensor pollicis brevis muscle

Answer 42

Dorsal surface of base of proximal phalanx of the thumb

Question 43

Action of extensor pollicis brevis muscle

Answer 43

Extends metacarpophalangeal joint of the thumb

Question 44

Innervation of extensor pollicis brevis muscle

Answer 44

Posterior interosseous nerve from radial nerve

Question 45

Origin of abductor pollicis longus muscle

Answer 45

• Posterior surfaces of the ulna and radius
  
  • Adjacent interosseous membrane

Question 46

Insertion of abductor pollicis longus muscle

Answer 46

Lateral side of the base of the first metacarpal

Question 47

Action of abductor pollicis longus muscle

Answer 47

Abducts carpometacarpal joint of thumb

Question 48

Innervation of abductor pollicis longus muscle

Answer 48

Posterior interosseous nerve from radial nerve