Anterior muscles of the forearm

Question 1

What are the superficial muscles of the forearm? (4)

Hint: pass, fail, pass, fail

Answer 1

• Pronator teres
• Flexor carpi radialis
• Palmar longus
• Flexor carpi ulnaris

Question 2

What is the common flexor origin?

Answer 2

The medial epicondyle of the humerus (above the trochlea of humerus)

Question 3

Flexor Carpi Ulnaris

Answer 3

O: Common flexor origin (humeral head) and medial margin of olecranon (ulnar head)

I: Pisiform bone and base of fifth metacarpal bone

I: Ulnar nerve (C8-T1)

A: Flexion and adduction of the wrist

Question 4

Palmaris Longus

Answer 4

O: Common flexor origin

I: Flexor retinaculum of the wrist and palmar aponeurosis

I: Median nerve (C6-T1)

A: Weak flexor of the wrist

Question 5

Flexor Carpi Radialis

Answer 5

O: Common flexor origin

I: Base of the second and third metacarpals

I: Median nerve

A: Flexion and abduction of the wrist

Question 6

Pronator Teres

Answer 6

O: Common flexor origin (humeral head) and coronoid process of the ulna (ulnar head)

I: Mid-shaft of the radius

I: Median nerve

A: Pronates the forearm

(Lateral border of pronator teres forms the medial border of the cubital fossa)

Question 7

What is the intermediate muscle of the anterior forearm?

Answer 7

Flexor digitorum superficialis

Question 8

Flexor Digitorum Superficialis

Answer 8

O: Common flexor origin, ulnar collaterl ligament coronoid process of the ulna (humeroulnar head) and anterior surface of the radius (radial head)

I: 4 tendons insert to the base of the middle phalanges of four fingers (exclude thumb)

I: Median nerve

A: Flexes metacarpophalangeal joints and interphalangeal joints of the four fingers. Also assists with flexion of wrist

Question 9

What are the muscles of the deep anterior forearm? (3)

Answer 9

• Flexor digitorum profundus
• Flexor pollicis longus
• Pronator quadratus

Question 10

Flexor Digitorum Profundus

Answer 10

O: Proximal two thirds of the ulnar shaft

I: 4 tendons inserts into the base of distal phalanges of the four fingers

I: Ulnar nerve (little and ring) and Radial nerve (middle and index)

A: Flex distal interphalangeal joints. Also flexes metacrpophalangeal joints and assist flexion of the wrist

Question 11

Flexor Pollicis Longus

Answer 11

O: Middle of the anterior surface of radial shaft

I: Distal phalanx of the thumb

I: Median nerve (anterior interosseous branch)

A: flex the interphalangeal joint and metacarpophalangeal joint of the thumb

Question 12

Pronator Quadratus

Answer 12

O: Anterior surface of the distal ulna

I: Anterior surface of distal radius

I: Median nerve (anterior interosseous branch)

A: Pronates the forearm at radio-ulnar joint