Muscles of the Hand

Question 0

abductor pollicis brevis

Answer 0

O: flexor retinaculum and tubercles of scaphoid and trapezium
I: lateral side of base of prox phalanx of thumb
N: recurrent branch of median nerve (C8, T1)
A: abducts thumb, helps oppose it

Question 1

opponens pollicis

Answer 1

O: flexor retinaculum and tubercles of scaphoid and trapezium
I: lateral side of 1st metacarpal
N: recurrent branch of median nerve (C8,T1)
A: to oppose thumb, it draws 1st metacarpal medially to center of
palm and rotates it medially

Question 2

flexor pollicis brevis

superficial and deep head

Answer 2

O: flexor retinaculum and tubercles of scaphoid and trapezium
I: lateral side of base of proximal phalanx of thumb
N: recurrent branch of median nerve (C8, T1)
A: flexes thumb

Question 3

adductor pollicis

Answer 3

O: oblique head– bases of 2nd and 3rd metacarpals, capitate,
and adjacent carpals
transverse head– ant surface of shaft of 3rd metacarpal
I: medial side of base of prox phalanx of thumb
N: deep branch of ulnar nerve (C8, T1)
A: adducts thumb toward lateral border of palm

Question 4

abductor digiti minimi

Answer 4

O: pisiform
I:medial side of base of prox phalanx of 5th finger
N: deep branch of ulnar nerve (C8,T1)
A: abducts 5th finger, assists in flexion of its prox phalanx

Question 5

flexor digiti minimi brevis

Answer 5

O: hook of hamate and flexor retinaculum
I: medial side of base of prox phalanx of 5th finger
N: deep branch of ulnar nerve (C8,T1)
A: flexes proximal phalanx of 5th finger

Question 6

opponens digiti minimi

Answer 6

O: hook of hamate and flexor retinaculum
I: medial border of 5th metacarpal
N: deep branch of ulnar nerve (C8,T1)
A: draws 5th metacarpal ant and rotates it, bringing 5th finger into
	oppostion w/ thumb

Question 7

lumbericals 1 and 2

Answer 7

O: lateral 2 tendons of flexor digitorum profundus
I: lateral sides of extensor expansions of 2nd-5th fingers
N: median nerve (C8,T1)
A: flex metacarpophalangeal joints, extend interphalangeal joints
of 2nd-5th fingers

Question 8

lumbericals 3 and 4

Answer 8

O: medial 3 tendons of flexor digitorum
I: lateral sides of extensor expansions of 2nd-5th fingers
N: deep branch of ulnar nerve (C8,T1)
A: flex metacarpophalangeal joints, extend interphalangeal joints
of 2nd-5th fingers

Question 9

dorsal interossei 1-4

Answer 9

O: adjacent sides of 2 metacarpals
I: bases of prox phalanges, extensor expnasions of 2-4 fingers
N: deep branch of ulnar nerve (C8,T1)
A: abduct 2-4 fingers from axial line, act w/ lumbericals in flexing
metacarpophalangeal joints and extending interphalangeal
joints

Question 10

palmar interossei 1-3

Answer 10

O: palmar surfaces of 2,4, and 5 metacarpals
I: bases of prox phalanges, extensor expansions of 2,4 and 5 f
fingers
N: deep branch of ulnar nerve (C8,T1)
A: adduct 2,4,5 fingers toward axial line, act w/ lumbricals in
flexing metacarpophalangeal joints and extending
interphalangeal joints