Deep layer of muscles in the anterior compartment of the forearm

Question 1

Flexor digitorum profundus

Answer 1

Origin:

• Anterior and medial surfaces of ulna and anterior medial had of interosseous membrane

Insertion:

• Four tendons, which attach to the palmar surfaces of the distal phalanges of the index, middle, ring and little fingers

Innervation:

• Lateral half by median nerve (anterior interosseous nerve)
• Medial half by ulnar nerve (C8, T1)

Function:

• Flexes distal interphalangeal joints of the index, middle, ring, and little fingers;
• Can also flex metacarpophalangeal joints of the same binders and the wrist joint

Question 2

Flexor pollicis longus

Answer 2

Origin:

• Anterior surface of radius and radial had of interosseous membrane

Insertion:

• Palmar surface of base of distal phalanx of thumb

Innervation:

• Median nerve (anterior, interosseous nerve) (C7, C8)

Function:

• Flexes interphalangeal joint of the thumb; can also flex metacarpophalangeal joint of the thumb

Question 3

Pronator quadratus

Answer 3

Origin:

• Lineal ridge on distal anterior surface of ulna

Insertion:

• Distal anterior surface of radius

Innervation:

• Median nerve (anterior interosseous nerve) (C7, C8)

Function:

• Pronation

Question 4

Origin:

• Anterior and medial surfaces of ulna and anterior medial had of interosseous membrane

Insertion:

• Four tendons, which attach to the palmar surfaces of the distal phalanges of the index, middle, ring and little fingers

Innervation:

• Lateral half by median nerve (anterior interosseous nerve)
• Medial half by ulnar nerve (C8, T1)

Function:

• Flexes distal interphalangeal joints of the index, middle, ring, and little fingers;
• Can also flex metacarpophalangeal joints of the same binders and the wrist joint

Answer 4

Flexor digitorum profundus

Question 5

Origin:

• Anterior surface of radius and radial had of interosseous membrane

Insertion:

• Palmar surface of base of distal phalanx of thumb

Innervation:

• Median nerve (anterior, interosseous nerve) (C7, C8)

Function:

• Flexes interphalangeal joint of the thumb; can also flex metacarpophalangeal joint of the thumb

Answer 5

Flexor pollicis longus

Question 6

Origin:

• Lineal ridge on distal anterior surface of ulna

Insertion:

• Distal anterior surface of radius

Innervation:

• Median nerve (anterior interosseous nerve) (C7, C8)

Function:

• Pronation

Answer 6

Pronator quadratus