Posterior forarm Flashcards
What are the superficial muscles of the posterior forearm?
brachioradialis extensor carpi radialis longus extensor carpi radialis brevis extensor carpi ulnaris extensor digiti minimi extensor digitorum
What are the deep muscles of the posterior forearm?
supinator abductor pollicis longus extensor pollicis longus extensor pollicis brevis extensor indicis
What nerve innervates all of the posterior forearm?
radial n.
What are the boundaries of the anatomical snuff box?
floor-scaphoid bone
roof-superficial radial n branch
lateral-extensor pollicis brevis tendon
medial-extensor pollicis longus tendon
What is contained inside the anatomical snuff box?
radial artery
What supplies blood to the posterior forearm?
posterior interosseous artery (branch of common interosseous artery)
perforating (posterior branch) of anterior interosseous artery
radial artery
What are the branches of the radial n.?
superficial branch (lateral) deep branch (posterior, becomes posterior interosseous nerve)
What motions are lost with a radial n. injury at the proximal humerus?
extension of elbow, weak supination
What motions are lost with a radial n. injury at the mid humerus?
“muscle weakness depends on location”
What motions are lost with radial n injury at the distal humerus?
wrist drop, inability to extend hand, MPJ and cant fully extend arm
What motions are lost with a radial n. injury at the wrist
loss of sensory to dorsal hand
What causes wrist drop?
radial n injury, paralysis of the wrist and finger extensors
What causes tennis elbow or “lateral epicondylitis”? what are the primary muscles involved?
overuse injury of extensor muscles (like in tennis)
extensor carpi radialis brevis
extensor digitorum
How would you test radial n function?
have patient extend MPJ against resistance
What tendons are involved in dequervains disease? what is the finkelstein test?
tendonitis of extensor pollicis brevis and abductor pollicis longus
-thumb in closed fist then wrist adduction tests for this
