Actions of Intrinsic Hand Muscles

Question 1

Which thenar muscle flexes and rotates the thumb medially (during grasping) (components of opposition)?

Answer 1

OPPONENS POLLICIS

Question 2

Which thenar muscle abducts the thumb and assists in opposition (abduction being a component of opposition)?

Answer 2

ABDUCTOR POLLICIS BREVIS

Question 3

Which thenar muscle flexes the thumb and assists in opposition (flexion being a component of opposition)?

Answer 3

FLEXOR POLLICIS BREVIS

Question 4

Name the hypothenar muscle which draws the 5th metacarpal anteriorly and rotates it to oppose the thumb?

Answer 4

OPPONENS DIGITI MINIMI

Question 5

Name the hypothenar muscle which abducts the 5th finger?

Answer 5

ABDUCTOR DIGITI MINIMI

Question 6

Name the hypothenar muscle which flexes the proximal phalanx of the 5th digit?

Answer 6

FLEXOR DIGITI MINIMI BREVIS

Question 7

Name the hypothenar muscle with 2 actions?

Answer 7

PALMARIS BREVIS

Question 8

Name the 2 (almost useless) actions of palmaris brevis?

Answer 8

1. WRINKLES SKIN ON MEDIAL SIDE OF PALM
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2. COVERS/PROTECTS ULNAR NERVE and ARTERY

Question 9

Which deep muscle of the hand adducts the thumb?

Answer 9

ADDUCTOR POLLICIS

Question 10

Which sock puppet muscles of the deep hand are responsible for the actions of MCP flexion and IP extension?

Answer 10

LUMBRICALS

Question 11

Which deep muscles of the hand aBduct the digits?

Answer 11

DORSAL INTEROSSEI

Question 12

Which deep muscles of the hand aDduct the digits?

Answer 12

PALMAR INTEROSSEI