Posterior Forearm Flashcards
(27 cards)
Extensor carpi radialis longus
Origin: lateral supracondylar ridge of humerus
Insertioin: dorsal aspect of base of 2nd metacarpal
Axns: extend and abduct hand at wrist
Blood: Radial collateral artery
radial recurrent ar.
recurrent interosseous
posterior interosseous ar
Nerve: radial nerve (C6, C7)
Extensor carpi radialis brevis
Origin: lateral epicondyle of humerus (common extensor origin)
Insertion: dorsal aspect of base of 3rd metacarpal
Axns: extend hand
abduct hand at wrist
Blood: radial collateral
radial recurrent
recurrent interosseous
post. interosseous
Nerve: deep branch of radial nerve (C7, C8)
Extensor digitorum
Origin: lateral epicondyle of humerus (common)
Insertion: extensor expansions of medial 4 fingers
Axns: extends medial 4 fingers at MCP joint
some at IP joints
Blood: post. interosseous ar
Recurrent interosseous ar
perforating branch of an. interosseous ar
Nerve: posterior interosseous nerve (C7, C8): continuation of deep branch of radial nerve
Extensor digiti minimi
Origin: lateral epicondyle of humerus
Insertion: extensor expansion of 5th finger
Axn: extend 5th finger at MCP and at IP joint
Blood: post. interosseous
recurrent interosseous
perforating branch of ant. interosseous
Nerve: post. interosseous nerve C7, C8
Extensor carpi ulnaris
Origin: lateral epicondyle of humerus
post. border of ulna (medial)
Insertion: dorsal base of 5th metacarpal
Axns: extends and adducts hand at wrist
Blood: radial collateral, radial recurrent, recurrent interosseous
post. interosseous ar
Nerve: posterior interosseous nerve (C7, C8)
Deep Extensors:
Supinator Extensor indicis Abductor pollicis longus Extensor pollicis longus extensor pollicis brevis
Supinator
Origin: lateral epicondyle of humerus
radial collateral and anular ligaments
ulnar crest
Insertion: prox. 1/3 of radius (nearly all surfaces, as it wraps around the bone)
Axns: supinates forearm, bringing radius back to anatomical postition
Blood: radial a post. interosseous radial recurrent recurrent interosseous middle collateral
Nerve: deep branch of radial nerve (C7, C8)
Extensor indicis
Origin: post. surface of distal 1/3 of ulna and interosseous membrane
Insertion: extensor expansion of 2nd finger
Axns: independent extension of 2nd finger, but also helps w/ extension of wrist
Blood: post. interosseous and perforating branch of ant. interosseous ar
Nerve: post. interosseous Nerve
Abductor pollicis longus (outcropping)
Origin: post. surface of prox. 1/2 of ulna and radius; interosseous membrane
Insertion: base of 1st metacarpal
Axns: abducts thumb and extends it at CMC joint
Blood: post. interosseous a
Nerve: post interosseous nerve (C7, C8)
Extensor pollicis brevis
Origin: post. surface of distal 1/3 of radius
interosseous membrane
Insertion: dorsal aspect of prox. phalanx of thumb
Axns: extends prox. phalanx of thumb at its MCP joint
extends CMC joint
Blood:Post. interosseous and perforating branch of anterior interosseous a
Nerve: post. interosseous nerve
Extensor Pollicis Longus
Origin: post. surface of middle 1/3 of ulna
interosseous membrane
Insertion: dorsal aspect of base of distal phalanx of thumb
Axns: extends distal phalanx of thumb at its interphalangeal joint
extends the MCP and CMC joint
Blood: post. interosseous and perforating branch of anterior interosseous a.
Nerve: posterior interosseous nerve
Brachioradialis
Origin: prox. 2/3 of supraepicondylar ridge of humerus
Insertion: distal radius: prox. to styloid process
Axns: flex forearm when pronated (mid prone or neutral)
Blood: radial collateral
recurrent radial
radial a.
Nerve: radial nerve (C5, 6, 7)
Posterior Compartment
Radial Nerve via:
Deep branch
OR
Posterior interosseous nerve
Radial Nerve
superficial branch and dorsal digital branches
Lateral Dorsal half of hand (anatomical position
Radialis (superficial lateral Group)
Brachioradioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Superficial group
Extensor carpi ulnaris
Extensor digiti minimi
Extensor digitorum
Deep Group
Extensor pollicis longus
Extensor indicis
Extensor pollicis brevis
Abductor pollicis longus
Supinator
Radial Nerve muscles
Brachioradialis
Extensor carpi radialis longus
Deep radial nerve muscles
Extensor carpi radialis brevis
Supinator
Posterior interossesous nerve
Extensor carpi ulnaris
Extensor digitorum
Extensor digiti minimi
Extensor indicis
Abductor pollicis longus
Extensor pollicis longus
Extensor pollicis brevis
Superficial radial nerve
Sensation of lateral half of dorsal wrist, hand, thumb
Brachioradialis
Origin: supraepicondylar ridge of humerus
Insertion: distal radius
Axns: flexes forearm (mid prone or neutral position)
Blood: radial collateral
recurrent radial
radial arteries
Nerve: Radial (C5, 6, 7)
Extensor Expansion and Extensor Hood Mechanism
Extensor digitorum contracts
pulls extensor hood (extensor expansion)
causes IP joints to extend
Lumbricals attach to this expansion at the hood (also able to extend IP joints)
Arterial Supply to posterior forearm and hand
Radial artery: via deep palmar arch (hand)
via dorsal carpal arch (hand)
Common interosseous artery
posterior interosseous artery
Perforating (posterior) branch of anterior interosseous artery
