Distal upper limb

Question 1

What are the muscles of the anterior forearm?

Answer 1

1: Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris

2: Flexor digitorum superficialis - has 4 tendons that each insert onto the middle phalynx ( PIP)

3: Prontator quadratus
Flexor digitorum profundus - has 4 tendons that each insert into the distal phalynx ( DIP)
Flexor pollicus longus

Question 2

What are the common functions of the anterior forearm muscles?

Answer 2

Flexion, abduction, adduction, pronation

Question 3

What innervates the anterior forearm muscles?

What muscles are the exception?

Answer 3

Median nerve

Ulnar nerve - flexor carpi ulnaris + 1/2 flexor digitorum profundus

Question 4

What are the muscles of the posterior forearm ?

Answer 4

Superficial layer :
Brachioradialis 
Extensor carpi radialis longus 
Extensor carpi radialis brevis 
Extensor digitorum
Extensor digit minimi
Extensor carpi ulnaris 

Deep layer: 
Supinator 
Abductor pollicus longus 
Extensor pollicus brevis
Extensor pollicus longus 
Extensor indices

Question 5

Which muscles is a transitional muscle and why?

Answer 5

Brachioradialis
Action = flexor
Orginates at the lateral epicondyle and innervated by the radial nerve

Question 6

What innervates the posterior hand compartment?

Answer 6

Radial nerve

Question 7

Describe the radial nerve above and below the wrist and its indications in radial nerve damage/radial nerve palsy

Answer 7

Radial nerve above wrist = muscular innervation
Radial nerve below wrist = cutaneous innervation as no muscles in the back of the hand

Radial nerve palsy

• Unable to extend the hand so wrist drop
• Loss of dorsal sensation

Question 8

What is the role of the extensor retinaculum and the extensor hood?

Answer 8

Extensor retinaculum keeps the tendons strapped to the bone so the muscles ( extensors of the digits/pollucis) can function properly

Extensor hood is where the tendons insert

Question 9

What are the 4 muscle groups of the hand?

What are their functions?

Answer 9

Thenar muscles : Opposition, flexion, abduction + adduction ( adductor pollicus)
Hypothenar muscles : Movements of the little finger
Lumbricals : Flexion + extension
Interossei ( DAB/PAD)

Question 10

What nerve innervates the hand?

Which muscles are the exception?

Answer 10

Ulnar

Median nerve innervates the thenar muscles

Question 11

Describe the arterial blood supply to the upper limb

Answer 11

Subclavian artery
Axillary artery
Brachial artery - at lower border of teres major
Gives a branch = profunda brachii artery
Bifurcates at cubital fossa -> radial + ulnar arteries

Question 12

Which artery forms the superficial palmar arch?

Which vein forms the deep palmar arch?

Answer 12

Ulnar

Radial