Posterior Forearm Flashcards
Into what functional groups are muscles of the posterior forearm organized?
Muscles that extend and abduct/adduct the hand at the wrist joint Muscles that extend the medial four digits Muscles that extend or abduct the thumb
What muscles in the posterior forearm extend and abduct/adduct the hand at the wrist joint?
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
What muscles in the posterior forearm extend the medial four digits?
Extensor digitorum
Extensor indicis
Extensor digiti minimi
What muscles in the posterior forearm extend or abduct the thumb?
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Identify the structures labelled 1-6
1- Brachioradialis 2- Extensor carpi radialis longus and brevis 3- Extensor digitorum 4- Extensor carpi ulnaris 5- Extensor digiti minimi 6- Anconeus
Identify the structures labelled 1-4
1- Supinator 2- Abductor pollicis longus 3- Extensor pollicis longus and brevis 4- Extensor indicis
What is the action of extensor carpi radialis longus and brevis on the wrist joint?
They both extend and abduct the wrist joint
Which muscles act during fist clenching?
Extensor carpi radialis longus and brevis Flexor carpi radialis
What is the action of extensor digitorum?
Extends the fingers and wrist
Where does extensor digitorum originate and terminate?
Originates at the common extensor origin from the lateral epicondyle
Fleshy belly ends in tendon in distal forearm that passes under extensor retinaculum and divides into tendons for the fingers
Which nerve innervates all the muscles of the posterior compartment of the forearm?
The radial nerve
What is the main action of extensor digitorum?
Extend medial four digits at MCPs
What is the main action of extensor carpi radialis longus?
Extends and abducts wrist
What is the main action of extensor carpi radialis brevis?
Extend and abduct wrist
What is the main action of brachioradialis?
Weak flexion of elbow
