Muscles that MOVE the thumb Flashcards
Extensor Pollicis Brevis
ORIGIN
The posterior shaft of radius.
INSERTION
Proximal phalanx of the thumb.
ACTION
Extends MCP joint of the thumb, extends and abducts CMC joint of the thumb, assists in wrist abduction.
INNERVATION
Radial.
Extensor Pollicis Longus
ORIGIN
The posterior shaft of ulna.
INSERTION
Distal phalanx of the thumb.
ACTION
Extension IP joint of the thumb, assists in extension of MCP and CMC joints of the thumb.
INNERVATION
Radial.
Opponens Pollicis
ORIGIN
Flexor retinaculum and trapezium.
INSERTION
Metacarpal bone of the thumb on radial side.
ACTION
Opposes CMC joint of the thumb.
INNERVATION
Median.
Abductor Pollicis Longus
ORIGIN
Posterior shafts of ulna and radius.
INSERTION
1st Metacarpal bone.
ACTION
Abduction and extension of the thumb.
INNERVATION
Radial.
Abductor Pollicis Brevis
ORIGIN
Flexor retinaculum, scaphoid, and trapezium.
INSERTION
Base of the proximal phalanx of the thumb.
ACTION
Abduction of the thumb.
INNERVATION
Median.
Adductor Pollicis
ORIGIN
Transverse head: Third metacarpal. Oblique head: Bases of the 2nd and the 3rd metacarpals.
INSERTION
Base of the proximal phalanx of the thumb.
ACTION
Adducts thumb at MCP and CMC joints.
INNERVATION
Ulnar.
Flexor Pollicis Longus
ORIGIN
Anterior shaft of radius.
INSERTION
Distal phalanx of the thumb.
ACTION
Thumb flexion.
INNERVATION
Median.
Flexor Pollicis Brevis
ORIGIN
Flexor retinaculum.
INSERTION
Proximal phalanx of the thumb.
ACTION
Flexes thumb at MCP joints.
INNERVATION
Median.
