Posterior forearm, Dorsum of hand, Joints of upper limb Session 30 Flashcards
(47 cards)
what innervates the posterior forearm
radial nerve
what r the two layer of muscles in the posterior forearm
superficial and deep
what r the 6 superficial muscles in the posterior compartment
brachioradialis extensor carpi radialis longus and brevis extensor digitorum extensor digiti minimi extensor carpi ulnaris
where do the superficial layer of muscle in the posterior compartment attach to
lateral epicondyle of the humerus
where is brachioradialis located and where does it insert
boundary between posterior and anterior compartments
inserts onto distal radius
action of brachioradialis
weak flexor of elbow joint
what r the insertions of the extensor carpi radialis longus and brevis
longus= 2nd metacarpal (index) brevis= 3rd metacarpal (middle)
actions of extensor carpi radialis longus and brevis
extend and abduct wrist
where does extensor digitorum insert onto
onto dorsal aspects of all four fingers
why is it difficult to fully extend the middle or ring finger independantly
tendons of extensor digitorum r connected by fibrous bands
where is the insertion and what is the action of extensor digiti minimi
inserts onto dorsum of pinky
extends little finger
what is the insertion and action of extensor carpi ulnaris
5th metacarpal
extends and adducts the wrist
what travels under the extensor retinaculum and what is the retinaculums function
all muscle tendons
prevents tendons from bowing when wrist is extended
what r the 5 deep muscles of the posterior compartment
supinator abductor pollicis longus extensor pollicis brevis extensor pollicis longus extensor indicis
what is the origin of the deep muscles and what is the exception
forearm bones and interosseous membrane
exception: supinator
what is the attachment of supinator and its interaction with the radius
origin from lateral epicondyle of the humerus
wraps around upper part of radialis
what three posterior forearm muscles r not extensors
brachioradialis
supinator
abductor pollicis longus
what is the action of supinator
supinates forearm
action and insertion of abductor pollicis longus
abducts thumb
inserts onto 1st metacarpal
what two muscles extend the thumb
extensor pollicis brevis and longus
what is the insertion and movements of extensor pollicis brevis
proximal phalanx
extends the metacarpalphalangeal joint
what is the insertion and movements of extensor pollicis longus
inserts onto distal phalynx
extends the interphalangeal joint of thumb (only muscle that can do this)
what is the insertion and action of extensor indicis
inserts onto dorsum of index finger
independant extension of index finger
what is the only intrinsic muscle on the dorsal aspect of the hand (group of muscles)
dorsal interossei