Blood and nerve supply to the forearm

Question 1

Which structures border the cubital fossa and which structures is it associated with?

Answer 1

Lateral + medial epicondyles, laterally by brachioradialis, medially by pronator teres, floor by brachialis muscle.
Radial nerve, biceps tendon, lateral cutaneous nerve to forearm, brachial artery, median nerve.

Question 2

What is the median cubital vein often used for and it forms a bridge between which vessels?

Answer 2

Venepuncture

Basilic + cephalic veins

Question 3

Outline the arterial supply of the forearm

Answer 3

Cubital fossa -> brachial artery divides into:
Radial artery -> under brachioradialis
Ulnar artery -> under flexor carpi ulnaris, gives off common interosseous.
Anastomosis around elbow joint

Question 4

Which nerves innervate the forearm?

Answer 4

Musculocutaneous nerve (lateral cutaneous nerve of forearm)
Radial nerve
Median nerve
Ulnar nerve

Question 5

What is the location, function and clinical significance of the median nerve?

Answer 5

Lies mid forearm between flexor digitorum superficialis + flexor digitorum profundus. passes through carpal tunnel.
Branch -> anterior interosseous nerve (to deep flexors)
Motor -> anterior compartment muscles, except flexor carpi ulnaris / medial part of flexor digitorum profundus + lateral hand muscles.
Sensory -> lateral palm + d1, d2, d3, ½ d4
Carpal tunnel syndrome –> median nerve compression (due to increased pressure in carpal tunnel associated with trauma, obesity, pregnancy).

Question 6

What is the function and clinical significance of the ulnar nerve?

Answer 6

Motor -> FCU + medial part FDP + intrinsic muscles of hand.
Sensory -> medial side of hand + ½ d4 + d5.
Cubital tunnel syndrome

Question 7

What is the location and branches of the radial nerve?

Answer 7

Enters forearm on lateral side under brachioradialis
Divides into two branches:
Superficial branch (sensory) -> under brachioradialis, winds round to dorsum of hand.
Deep branch -> posterior interosseous nerve (motor), passes through supinator muscle, enters extensor compartment.

Question 8

What are the functions and clinical significance of the radial nerve?

Answer 8

Motor -> deep branch supplies posterior compartment muscles.
Sensory -> superficial branch supplies dorsolateral aspect of hand.
Wrist drop