Exam 2 Dorsal Forearm And Hand Flashcards
What is the insertion of the brachioradialis?
lateral surface of distal end of radius proximal to styloid process
What is the origin of the brachioradialis?
proximal two thirds of lateral supraepicondylar ridge of humerus
What is the innervation of the brachioradialis?
Radial nerve C5, C6, C7
What is the main action of the brachioradialis?
Relatively weak flexion of the elbow joint, maximal when forearm is in midpronated position
What is the origin of the extensor carpi radialis longus?
Lateral supra-epicondylar ridge of humerus
What is the insertion of the extensor carpi radialis longus?
Dorsal aspect of base of 2nd metacarpal
What is the innervation of the extensor carpi radialis longus?
Radial Nerve C6, C7
What is the main action of the extensor carpi radialis longus?
Extend and abduct wrist joint
What is the origin of the extensor carpi radialis brevis?
Lateral epicondyle of humerus
What is the insertion of the extensor carpi radialis brevi?
Dorsal aspect of base of 3rd metacarpal
What is the innervation of the extensor carpi radialis brevis?
Deep branch of radial nerve C7, C8
What is the action of the extensor carpi radialis brevis?
Active during fist clenching
What is the origin of extensor digitorum?
Lateral epicondyle of humerus
What is the insertion of the extensor digitorum?
Extensor expansions of medial four fingers
What is the innervation of the extensor digitorum?
Posterior interosseous nerve C7, C8, continuous of deep branch of radial nerve
What is the main action of extensor digitorum?
Extend wrist joint, extend medial four fingers primarily at metacarpophalangeal joints
What is the origin of the extensor digiti minimi?
Lateral epicondyle of humerus
What is the insertion of extensor digiti minimi?
Extensor expansion of 5th finger
What is the innervation of extensor digiti minimi?
Posterior interosseous nerve C7, C8, continuous of deep branch of radial nerve
What is the main action of extensor digiti minimi?
Extends wrist joint; extends 5th finger primarily at metacarpopphhalaangeal joint, secondarily at interphalangeal joint
What is the origin of the extensor carpi ulnaris?
Lateral epicondyle of humerus, posterior border of ulna via a shared aponeurosis
What is the insertion of the extensor carpi ulnaris?
Dorsal aspect of base of 5th metacarpal
What is the innervation of extensor carpi ulnaris?
Posterior interosseous nerve C7, C8; continuous of deep branch of radial nerve
What is the action of extensor carpi ulnaris?
Extends and adducts wrist joint (also active during fist clenching)
What is the origin of the supinator?
Lateral epicondyle of humerus; radial collateral and anular ligamennts; supinator fossa; crest of ulna
What is the insertion of the supinator?
Lateral, posterior, and anterior surfaces of proximal third of radius
What is the innervation of the supinator?
Deep branch of radial nerve C7, C8
What is the action of the supinator?
Supinates forearm, rotates radius to turn palm anteriorly or superiorly (if elbow is flexed)
What is the origin of the abductor pollicis longus?
Posterior surface of proximal halves of ulna, radius, interosseous membrane
What is the insertion of the abductor pollicis longus?
Base of 1st metacarpal
What is the innervation of the abductor pollicis longus?
Posterior interosseous nerve C7, C8; continuation of deep branch of radial nerve
What is the action of the abductor pollicis longus?
Extends wrist joint; abducts thumb and extends it at carpometacarpal joint
What is the origin of the extensor pollicis longus?
Posterior surface of middle third of ulna and interosseous membrane
What is the insertion of the extensor pollicis longus?
dorsal aspecct of base of distal phalanx of thumb
What is the innervation of the extensor pollicis longus?
Posterior interosseous nerve C7, C8; continuation of deep branch of radial nerve
What is the action of the extensor pollicis longus?
extends wrist joint; extends distal phalanx of thumb at interphalangeal joint; extends metacarpophalangeal and carpometacarpal joints
What is the origin of the extensor pollicis brevis?
Posterior surface of distal third of radius and interosseous membrane
What is the insertion of extensor pollicis brevis?
Dorsal aspecct of base of proximal phalanx of thumb
What is the innervation of extensor pollicis brevis?
Posterior interosseous nerve C7, C8; continuation of deep branch of radial nerve
What is the action of extensor pollicis brevis?
extends wrist joint; extends proximal phalanx of thumb at metacarpophalangeal joint; extends carpometacarpal joint
What is the origin of extensor indicis?
Posterior surface of distal third of ulna and interosseous membrane
What is the insertion of the extensor indicis?
Extensor expansion of 2nd finger
What is the innervation of extensor indicis?
Posterior interosseous nerve C7, C8; continuation of deep branch of radial nerve
What is the action of extensor indicis?
Extends wrist joint; extends 2nd finger; helps extend hand at wrist
