Flashcards in Upper Limb 4 Deck (30):
Name the muscles that extend and abduct or adduct the hand at the wrist joint
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
What is the action of extensor carpi radialis longus and brevis on the wrist joint?
They both abduct and extend the wrist joint
Apart from extending the wrist joint what other action is the extensor carpi radialis longus and brevis involved with , with the help of the flexor carpi ulnaris?
Name 3 muscles that extend the medial 4 digits
Extensor digiti minimi
Where does the extensor digitorum arise from?
Common extensor origin from the lateral epicondyle
Where does the extensor digitorim end?
In the distal part of the forearm, its fleshy belly ends in a tendon which passes under cover of the extensor retinaculum, and divides into tendons for the fingers
The extensor digitorum is an extensor of which joints?
Wrist and fingers
Which nerve innervates all the muscles of the posterior compartment of the forearm?
What is the innervation and action of extensor digitorum?
-Deep branch of Radial N (Post. Interosseous N)
-Extend medial 4 digits at MCP joints
What is the innervation and action of Extensor Carpi radials longus and brevis?
-Radial N. (Longus)
-Deep branch of Radial N. (Brevis)
-Extend and abduct wrist joint
WHat is the innervation and action of the Brachioradialis?
-Relatively weak flexion of elbow
-Maximal when forearm mid pronated
What is the innervation and action of the extensor carpi ulnaris?
-Continuation of Deep Radial N (Post. interosseous N)
-Extends and adducts wrist
What is the innervation and action of the supinator?
-Deep branch of Radial N
What is the innervation and action of the extensor digiti minimi?
-Deep branch of Radial N. (Post Interosseous N)
-Extends 5th finger at MP joint
Where does the supinator muscle lie?
Envelops the neck and the proximal part of the shaft of the radius, covering it completely, except on its medial side
What is the nerve supply to the supinator muscle?
Deeb branch of radial N
What two nerves does the radial nerve divide into in the cubital fossa?
Superficial and deep branches
What is the other name for the deep branch of the radial nerve?
Posterior interosseous nerve
What is the function of the superficial branch of the radial nerve?
Sensory and distributed to skin on the dorm of the hand
The main superficial veins of the upper limb originate where?
In the subcutaneous tissue on the dorsum of the hand
What are synpvial cysts/ ganglions?
(What, Where, WHat do they communicate with?)
Non-tender cystic growth appears most commonly on the dorsum of hand.
Most often they communicate with the synovial sheaths covering the tendons
What deep muscles of the forearm act on the thumb?
How do they form the border of the anatomical snuffbox?
Abductor Pollicis Longus
Extensor Pollicis Brevis
Extensor Pollicis Longus
The tendon of Abductor Pollicis Longus and Extensor Pollicis Brevis bound the anatomical snuff box laterally
The tendon of Extensor Pollicis Longus bounds it medially
What two carpal bones can you feel in the anatomical snuff box?
Which artery lies on the floor of the snuff box?
Which nerve innervates extensor pollicis longus, extensor pollicis brevis and abductor pollicis longus?
Deep branch of Radial N
(Post. interosseous N)
What is the action of Extensor pollicis longs?
Extends wrist joint
Extends distal phalanx of thumb
What is the action of Extensor pollicis brevis?
Extends wrist joint
Extends proximal phalanx of thumb
What is the action of Abductor pollicis longus?
Four extensor digitorum tendons flatten to form extensor expansions (dorsal expansion or hood).
Explain the structure of these extensor expansions
Triangular aponeurosis that wraps around the dorm and sides of a head of the metacarpal and base of the proximal phalanx