Session 5 - Posterior Muscles of the forearm Flashcards
Name the seven superficial muscles in the posterior compartment of the forearm
brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris and aconeus
What are the muscles in the posterior compartment of the forearm also known as?
The extensor muscles
What occurs in all superficial posterior muscles bar two?
Continue as tendons into the hand
What are the two muscle in the superficial posterior compartment of the forearm with tendons which do not extend into the hand?
The brachioraialis and aconeus
What is A?
The brachioradialis
What name can all superficial posterior muscles be known as, other than the aconeous and brachioradialis
Extrinsic hand muscles
What type of movement is the brachioradialis responsible for? Why is this weird?
Flexion Origin and innervation are characteristic of extensor, and lies in extensor compartment
In the distal forearm, what can be found below the brachioradialis?
The radial artery and nerves
What is the brachioradialis most visible?
When half pronated and fleing at the elbow against resistance
What is the action of the brachioradialis?
Flexion at the elbow
What is the innervation of the brachioradialis?
Radial nerve
What are B and C?
Extensor Carpi Radialis Longus and Brevis
What is the aciton of the extensor carp radialis longus and brevis?
Extension and abduction of the wrist
What is the innervation of every muscle in this deck?
Radial nerve, so yeh.
What are the nerve roots of the radial nerve?
C5-T1
What is D?
The Aconeus
What is the aconeus blended with?
Fibres of the triceps brachii
What is the action of the aconeus?
Moves the ulna during pronation and extends at the elbow joint
What is E?
Extensor Carpi Ulnaris
What is the action of the extensor carpi ulnaris?
Extension and adduction of wrist
What is F?
Extensor Digitorum
What is significant about the extensor digitorum (think about the name)
Main extensor of the fingers, makes up most of the posterior surface of the forearm
What are the actions of the extensore digitorum?
Extends medial four finger at metacarpal and IP joints
What is G?
Extensor Digiti Minimi
What is the action of the Extensor Digiti Minimi
Extends the little finger and contributes to extension at the wrist
What occurs if there is injury to the radial nerve?
Wrist drop Radial nerve innervates the muscles that extend at the wrist and are paralysed. The wrist undergoes unopposed flexion and wristdrop results
Name five deep muscles of the posteior forearm
the supinator, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus and extensor indicis
What is A?
Supinator
What does the supinator form the floor of?
The cubital fossa
What is the action of the supinator
Supinates the forearm
What is B?
Abductor pollicis longus
What border does the abductor pollicus longus contribute to?
The lateral border of the anatomical snuff box
What is the action of the abductor pollicis longus?
Abducts the thumb
What is C?
Extensor indicis
What is the action of the extensor indicis?
Extends the index finger
What is D?
Extensor Pollicis Brevis
What is the action of the extensor pollicis brevis?
Extends the MCP and carpometacarpal joints of the thumb
What border does extensor pollicis brevis contribute to?
The lateral border of the anatomical snuff box
What is E?
Extensor Pollicis Longus
What is the action of the abductor pollicis longus?
Abducts the thumb
