posterior compartment of forearm: extensor and supination

Question 1

extensor digitorum

Answer 1

• origin: lateral epicondyle of the humerus: common extensor tendon
• insertion: extensor expansion of digits 2-5
• action: extends the metacarpophalangeal and interphalangeal joints, extends wrist when fingers are extended

Question 2

extensor digiti minimi

Answer 2

• origin: lateral epicondyle of the humeru:common extensor tendon
• insertion: extensor expansion to 5th digit
• action: extends the metacarpophalangeal and interphalangeal joint, extends wrist when fingers are extended

Question 3

extensor carpi ulnaris

Answer 3

• origin: common extensor tendon & posterior border of the ulna
• insertion: base of the 5th metacarpal
• action: extends and adducts the hand at the wrist joint

Question 4

deep extensor region

Answer 4

• abductor pollicis longus
• extensor pollicis longus
• extensor pollicis brevis
• extensor indicis
• supinator