posterior forearm muscles Flashcards
Brachioradialis
PA: upper lateral supracondylar ridge
DA: proximal to radial styloid process
N: radial c5-7
A: flex elbow in midpronation, supinate/pronate to midpronation, “handshake muscle”
Extensor Carpi Radialis Longus
PA: lower lateral supracondylar ridge
DA: dorsum and base of 2nd MC
N: radial c6-7
A: extends wrist, radial deviate, weak elbow flexion
Extensor Carpi radialis Brevis
PA: common extensor tendon on lateral epicondyle
DA: dorsum and base of 3rd MC
N: deep radial c7-8
A: extend and radial deviate wrist, weak elbow extension
Extensor Digitorum
PA: common extensor tendon on lateral epicondyle
DA: extensor expansion of digits 2-5
N: PIN c7-8
A: extends MCP, assists with extension of DIP, PIP digits 2-5, weak wrist extension, weak elbow extension
Extensor Digiti Minimi
PA: common extensor tendon on lateral epicondyle
DA: extensor expansion of 5th digit
N: PIN c7-8
A: extends 5th MCP, assists with extension of PIP and DIP 5th digit, elbow extension
Extensor Carpi Ulnaris
PA: common extensor tendon on lateral epicondyle and posterior border of ulna
DA: dorsal base of 5th MC
N: PIN c7-8
A: extend and ulnar deviate, elbow extension
Extensor Indicis
PA: posterior distal ulna and IO
DA: extensor expansion of 2nd digit
N: PIN c7-8
A: extends 2nd MCP, assist with extension of DIP and PIP, weak wrist extension
Extensor Pollicis Brevis
PA: IO and posterior surface of distal radius
DA: base of proximal phalanx of thumb
N: PIN c7-8
A: extends 1st MCP and CMC
Extensor Pollicis Longus
PA: IO and middle part of posteriolateral surface of ulna
DA: base of distal phalanx of thumb
N: PIN c7-8
A: extends IP, MCP, CMC
Abductor Pollicis Longus
PA: middle 1/2 posterior radius, IO, middle posterolateral ulna
DA: radial side of base of 1st MC
N: PIN c7-8
A: ABD and extends 1st CMC
Supinator
PA: lateral epicondyle, supinator crest, RCL, annular ligament
DA: lateral, posterior and anterior proximal 1/3 of radius
N: deep radial c7-8
A: supinate forearm
