anterior deep compartment of forearm (flexion and pronation)

Question 1

flexor digitorum profundus

Answer 1

• origin: posterior border of the ulna, proximal two-thirds of medial border of ulna, interosseous membrane
• insertion: base of the distal phalanx of digits 2-5
• action: flexes the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints

Question 2

flexor pollicis longus

Answer 2

• origin: anterior surface of radius and interosseous membrane
• insertion: base of the distal phalanx of the thumb
• action: flexes the metacarpophalangeal and interphalangeal joints of the thumb

Question 3

pronator quadratus

Answer 3

• origin: medial side of the anterior surface of the distal one-fourth of the ulna
• insertion: anterior surface of the distal one-fourth of the radius
• action: pronates the forearm