Flexors of the Forearm

Question 1

What are the layers of the forearm flexors?

Answer 1

• Superficial layer
• Intermediate layer
• Deep layer

Question 2

What are the muscles of the superficial layer of the forearm?

Answer 2

Medial –> lateral:
* Flexor carpi ulnaris
* Flexor carpi longus
* Flexor carpi radialis
* Pronator teres

Question 3

Origin of the flexor carpi radialis

Answer 3

Medial epicondyle of the humerus

Question 4

Insertion of the flexor carpi radialis

Answer 4

Base of metacarpals 2 and 3

Question 5

Action of flexor carpi radialis

Answer 5

Flexes and abducts the wrist joint

Question 6

Nerve supply of the flexor carpi radialis

Answer 6

Median nerve

Question 7

Origin of the palmaris longus

Answer 7

Medial epicondyle of the humerus

Question 8

Insertion of palmaris longus

Answer 8

Palmar aponeurosis of the hand

Question 9

Action of palmaris longus

Answer 9

• Flexion of wrist joint
• Tenses the skin when the hand grips

Question 10

Nerve supply of palmaris longus

Answer 10

Median nerve

Question 11

Origins of the flexor carpi ulnaris

Answer 11

• Medial epicondyle
• Olecranon
• Posterior border of ulna

Question 12

Insertions of the flexor carpi ulnaris

Answer 12

• Pisiform bone
• Hamate
• Base of metacarpal 5

Question 13

Action of the flexor carpi ulnaris

Answer 13

Flexes and adducts the wrist joint

Question 14

Nerve supply of flexor carpi ulnaris

Answer 14

Ulnar nerve

Question 15

Origins of the pronator teres

Answer 15

• Medial epicondyle
• Coranoid process

Question 16

Insertion of the pronator teres

Answer 16

Lateral surface, mid-shaft of radius

Question 16

Action of the pronator teres

Answer 16

Pronation

Question 16

Nerve supply of the pronator teres

Answer 16

Median nerve

Question 17

What are the muscles of the intermediate layer?

Answer 17

Flexor digitorum superficialis

Question 18

Origin of flexor digitorum superficialis

Answer 18

• Medial epicondyle of the humerus
• Coronoid process
• Oblique line of the radius

Question 19

Insertion of the flexor digitorum superficialis

Answer 19

Palmar surface of the middle phalanges of the medial 4 fingers

Question 20

Action of flexor digitorum superficialis

Answer 20

• Flexes proximal inter-phalangeal joints of the medial 4 fingers
• Flex metacarpo-phalangeal joints of the same fingers and the wrist joint

Question 21

Nerve supply of flexor digitorum superficialis

Answer 21

Median nerve

Question 22

What are the muscles of the deep layer?

Answer 22

• Flexor digitorum profundus
• Flexor policis longus
• Pronator quadratus

Question 23

Origin of flexor digitorum profundus

Answer 23

Upper part of front of ulna

Question 24

Insertion of flexor digitorum profundus

Answer 24

Palmar surfaces of the distal phalanges (medial 4 fingers)

Question 24

Insertion of flexor digitorum profundus

Answer 24

Palmar surfaces of the distal phalanges (medial 4 fingers)

Question 25

Action of flexor digitorum profundus

Answer 25

Flexes distal inter-phalangeal joints, metacarpo-phalangeal joints of the medial 4 fingers and flexes the wrist joint

Question 26

Nerve supply of flexor digitorum profundus

Answer 26

Lateral ½ by anterior interosseous branch of median nerve Medial ½ by ulnar nerve

Question 27

Origin of flexor policis longus

Answer 27

Upper part of anterior surface of radius

Question 28

Insertion of flexor policis longus

Answer 28

Palmar surface of base of distal phalanx of thumb

Question 29

Action of flexor policus longus

Answer 29

* Flexes inter-phalangeal joint * Flexes metacarpo-phalangeal joints of the thumb

Question 30

Nerve supply of flexor policis longus

Answer 30

Anterior interosseous of median nerve

Question 31

Diagram of flexor digitorum profundus and flexor digitorum superficialis

Answer 31

Question 32

Origin of pronator quadratus

Answer 32

Distal anterior surface of ulna

Question 33

Insertion of pronator quadratus

Answer 33

Distal anterior surface of radius

Question 34

Action of pronator quadratus

Answer 34

Pronation

Question 35

Nerve supply of pronator quadratus

Answer 35

Anterior interosseous branch of median nerve

Question 36

What is the origin of the radial artery?

Answer 36

Originates from the brachial artery at the neck of radius

Question 37

Describe the course of the radial artery

Answer 37

**In proximal and middle forearm**: Lies deep to the brachioradialis muscle **In distal forearm**: Lies between the tendon of the brachioradialis laterally and the tendon of flexor carpi radialis medially

Question 38

What is the origin of the ulnar artery?

Answer 38

Originates from the brachial artery at the neck of radius

Question 39

What is the course of the ulnar artery?

Answer 39

* Leaves the cubital fossa by passing deep to the pronator teres muscle * Passes through the forearm between flexor carpi ulnaris and flexor digitorum profundus muscles * Distal forearm, it lies lateral to the ulnar nerve