testing posterior forearm

Brachioradialis origin

Lateral supraepicondylar ridge of humerus

Brachioradialis insertion

Lateral surface of distal radius

Brachioradialis innervation

Radial

Brachioradialis action

Flexes forearm

Extensor carpi radialis longus origin

Lateral supraepicondylar ridge of humerus

Extensor carpi radialis longus insertion

Base of 2nd metacarpal

Extensor carpi radialis longus innervation

Radial

Extensor carpi radialis longus action

Extends and abducts hand

Extensor carpi radialis brevis origin

Lateral epicondyle of humerus

Extensor carpi radialis brevis insertion

Base of 3rd metacarpal

Extensor carpi radialis brevis innervation

Radial

Extensor carpi radialis brevis action

Extends and abducts hand

Extensor digitorum origin

Lateral epicondyle of humerus

Extensor digitorum insertion

Extensor expansions to middle and distal phalanges of digits 2-5

Extensor digitorum innervation

Radial

Extensor digitorum action

Extends digits 2-5 at MCP and IP joints

Extensor digiti minimi origin

Lateral epicondyle of humerus

Extensor digiti minimi insertion

Extensor expansions to middle and distal phalanges of digit 5

Extensor digiti minimi innervation

Radial

Extensor digiti minimi action

Extends digit 5 at MCP and IP joints

Extensor carpi ulnaris origin

Lateral epicondyle of humerus, posterior surface of ulna

Extensor carpi ulnaris insertion

Base of 5th metacarpal

Extensor carpi ulnaris innervation

Radial

Extensor carpi ulnaris action

Extends and adducts hand

Supinator origin

Lateral epicondyle of humerus, supinator fossa and crest of ulna

Supinator insertion

Lateral, posterior, and anterior surfaces of radius

Supinator innervation

Radial

Supinator action

Supinates forearm

Abductor pollicis longus origin

Posterior surface of ulna and radius

Abductor pollicis longus insertion

Base of 1st metacarpal

Abductor pollicis longus innervation

Radial

Abductor pollicis longus action

Abducts and extends digit 1 at carpometacarpal joint

Extensor pollicis longus origin

Posterior surface of ulna

Extensor pollicis longus insertion

Distal phalanx of digit 1

Extensor pollicis longus innervation

Radial

Extensor pollicis longus action

Extends digit 1 at IP, MCP, and carpometacarpal joints

Extensor pollicis brevis origin

Posterior surface of radius

Extensor pollicis brevis insertion

Proximal phalanx of digit 1

Extensor pollicis brevis innervation

Radial

Extensor pollicis brevis action

Extend digit 1 at MCP and carpometacarpal joints

Extensor indicis origin

Posterior surface of ulna

Extensor indicis insertion

Extensor expansion to middle and distal phalanges of digit 2

Extensor indicis innervation

Radial

Extensor indicis action

Extend digit 2 at MCP and IP joints