Anatomy of the Hand and Wrist

Question 1

what are the flexor muscles of the forearm?

Answer 1

Red is brachioradialis

Blue is pronator teres and causes pronation – causes elbow joint anteriorly so is also an elbow flexor

Yellow and orange are both flexors of the wrist as cross that joint

Orange is flexor carpi ulnaris

Yellow is flexor carpi radialis

Brachialis is supplied by radial nerve

Rest in forearm is median nerve except yellow which is ulnar nerve

Question 2

what are the extensor muscles of the forearm?

Answer 2

Extensor carpi ulnaris

Extensor carpi radialis but you have longus and brevis, longus is the yellow one

All common extensor

Supplied by radial nerve

Palmaras longus – don’t really need it

Both these views are superficial

All left are elbow flexors and right extensors as cross the elbow joint

Question 3

what are the deeper flexors and extensors of the forearm?

Answer 3

Left is on epicondyle and middle is not - Middle does not cross elbow joint

Flexor digitorum superficialis – left picture, fingers for 3 falanges and this muscle attaches on the second/middle, assists flexing every joint it crosses

PIP – proximal interphalangeal joint

Blue is the flexor digitorum profundus, no longer an elbow flexor but its tendors go all the way to the end of the fingers, only muscle to flex the terminal joint sin the fingers

Thumb is different - Thumb only has 2 phalanges

Flexor policis longus is the left blue muscle going to the thumb

Tendons of blue run through a shared space called carpel tunnel

Onto purple on posterior side

Outside is called the extensor digitorum (communis)

Inside is called the extensor digit mininimi (quinti) – goes to 1 finger

Question 4

what are the posterior extensors and abductors?

Answer 4

Lateral aspect of forearm to the thumb

Thumb sits at a right angle to the fingers

Lifting thumb in air is abduction, pushing thumb out is extension and in over palm is flexion

Extensors of the thumb are the inner blue and red, red is shorted and is brevis and blue is longer and is longus – extensor policis brevis and longus

Big blue is the abductor policis longus

Green is the extensor indicis

Easy to extend pinky and index finger as got individual muscles

Question 5

what are the different movements of the fingers?

Answer 5

Spreading fingers on bottom left is abduction – pulling second fourth and fifth digit away form the third

Fingers coming together is adduction

Making a fist is flexion and flattening out is extension

Pulling thumb up is abduction and putting it back down is adduction

Question 6

what are the palmar adductors and the dorsal abductors?

Answer 6

On dorsal surface of the hand but have been drawn from the anterior palmar surface

Deep as all the muscles are lying above them

Only need 3 muscles for adduction – for fingers 2, 4 and 5

For DAB there is now 2 muscles for the middle digit

All supplied by ulnar nerve