Posterior Forearm Muscles Flashcards
Origin of the brachioradialis
Proximal 2/3 of lateral supracondylar ridge of humerus
Insertion of the brachioradialis
Lateral surface of distal end of radius, proximal to styloid process
What does the brachioradialis do?
Flexes the forearm at the elbow joint
What innervates the brachioradialis?
Radial nerve
Origin of the extensor carpi radialis longus
Lateral supracondylar ridge of humerus
Insertion of the extensor carpi radialis longus
Base of 2nd metacarpal
What does the extensor carpi radialis longus do?
Extend and abduct hand at wrist joint
What innervates the extensor carpi radialis longus?
Radial nerve
Origin of the Extensor Carpi Radialis Brevis
Lateral epicondyle of humerus
Insertion of the Extensor Carpi Radialis Brevis
Base of 3rd metacarpal
What does the Extensor Carpi Radialis Brevis do?
Extend and abduct (radial deviation) hand at wrist joint
What innervates the Extensor Carpi Radialis Brevis?
Radial nerve
Origin of the Extensor Digitorum
Lateral epicondyle of humerus
Insertion of the Extensor Digitorum
Extensor expansions of medial four digits
What does the extensor digitorum do?
Extends medial four digits at metacarpophalangeal joints
Extends hand at wrist joint
What innervates the extensor digitorum?
Radial nerve
Origin of the extensor digitorum minimi
Lateral epicondyle of humerus
Insertion of the extensor digitorum minimi
Extensor expansion of 5th digit
What does the extensor digitorum minimi do?
Extends 5th digit at metacarpophalangeal and interphalangeal joints
What innervates the extensor digitroum minimi?
Radial nerve
Origin of the extensor carpi ulnaris
Lateral epicondyle of humerus
Posterior border of ulna
Insertion of the extensor carpi ulnaris
Base of 5th metacarpal
What does the extensor carpi ulnaris do?
Extends and adducts (ulnar deviation) hand at wrist joint
What innervates the extensor carpi ulnaris?
Radial nerve
Origin of the supinator
Lateral epicondyle of humerus
Radial collateral and annular ligaments
Supinator fossa
Crest of ulna
Insertion of the supinator
Lateral, posterior and anterior surfaces of proximal third of radius
What does the supinator do?
Supinates forearm (i.e. rotates radius to turn palm anteriorly)
What innervates the supinator?
Radial nerve
Origin of the extensor indicis
Posterior surface of ulna and interosseous membrane
Insertion of the extensor indicis
Extensor expansion of 2nd digit
What does the Extensor Indicis do?
Extends 2nd digit and helps to extend hand
What innervates the extensor indicis?
Radial nerve
Origin of the abductor pollicis longus
Posterior surface of proximal ½ of ulna, radius and interosseous membrane
Insertion of the abductor pollicis longus
Base of 1st metacarpal
What does the abductor pollicis longus do?
Abducts thumb and extends it at carpometacarpal joint
What innervates the abductor pollicis longus?
Radial nerve
Origin of the extensor pollicis longus
Posterior surface of middle third of ulna and interosseous membrane
Insertion of the extensor pollicis longus
Base of distal phalanx of thumb
What does the extensor pollicis longus do?
Extends distal phalanx of thumb at carpometacarpal and interphalangeal joints
What innervates the extensor pollicis longus?
Radial nerve
Origin of the extensor pollicis brevis
Posterior surface of distal third of radius and interosseous membrane
Insertion of the extensor pollicis brevis
Base of proximal phalanx of thumb
What does the extensor pollicis brevis do?
Extends proximal phalanx of thumb at carpometacarpal joint
What innervates the extensor pollicis brevis?
Radial nerve