Upper Limb: Forearm & Hand

Question 1

What are the 5 sites of physiological ulnar nerve compression in the arm & forearm?

Answer 1

1) Arcade of Struthers
2) Medial intermuscular septum
3) Cubital tunnel / Obsbourne’s fascia
4) Deep flexor pronator aponeurosis
5) Guyon’s canal / pisohamate ligament

Question 2

Between which muscle does the ulnar nerve pass through in the forearm?

Answer 2

2 heads of flexor carpii ulnaris

Question 3

Which muscles does the ulnar nerve innervate in the forearm?

Answer 3

1) Flexor carpii ulnaris

2) Medial 1/2 of flexor digitorum profundus

Question 4

What forms the borders of the anatomical snuffbox?

A) Posterior border
B) Anterior border
C) Proximal border
D) Distal border
E) Floor
F) Content

Answer 4

A) Tendon of extensor pollicis longus

B) Tendons of extensor pollicis brevis and abductor pollicis longus

C) Styloid process of the radius

D) Apex of snuffbox triangle

E) Trapezium and scaphoid

F) Radial artery

Question 5

How many tunnels/compartments does the extensor retinaculum of the hand have?

Answer 5

6

Question 6

What are the attachments of the extensor retinaculum?

Answer 6

MEDIAL

• Pisiform
• Triquetral

LATERAL
- End of radius

Question 7

What structures lie superficial to the extensor retinaculum?

Answer 7

1) Cephalic vein
2) Basilic vein
3) Superficial radial nerve
4) Cutaneous branch of ulnar nerve

Question 8

Which nerve is affected in an abberent gantzer muscle?

Answer 8

AIN