WRIST

Question 1

Label the carpal bones

Answer 1

Question 2

What are two important complications of scaphoid bone fractures?

Answer 2

• Avascular necrosis
• Non-union

Question 3

What is the blood supply to the scaphoid bone? Why is it at risk of avascular necrosis in fracture?

Answer 3

Radial artery

→ supplies distal portion of bone first then works proximally, relying on retrograde flow. In a fracture, proximal blood supply is compromised

Question 4

The anterior dislocation of which bone can lead to median nerve dysfunction? Explain why

Answer 4

Lunate

sits on top of carpal tunnel so can compress it

Question 5

What is the name of the strong, fibrous band that covers the carpal bones on the palmar side of the hand near the wrist? What lies beneath?

Answer 5

Flexor retinaculum (carpal ligament)

carpal tunnel

Question 6

List 3 Endocrine risk factors for carpal tunnel syndrome?

Answer 6

• Acromegaly: up to a third of patients
• T1 diabetes
• Hypothyroidism

Question 7

Which renal condition increases risk of carpal tunnel syndrome?

Answer 7

Dialysis-related amyloidosis

Amyloid deposits form from beta2 microglobulin which accumulates in the carpal tunnel

Question 8

What is the name of this test?

Answer 8

Tinel’s test

Question 9

What is the name of this test?

Answer 9

Phalen’s manoeuvre

Question 10

Which canal carries the ulnar nerve and artery to the wrist? Where does this lie in relation to the transverse carpal ligament?

Answer 10

Guyon’s canal (ulnar canal)

ABOVE transverse carpal ligament

Question 11

Which nerve is responsible for the abduction and adduction of fingers?

Answer 11

Ulnar - innervates the interossei muscles

Question 12

Overuse of the wrists and direct pressure on the handlebars of a bike are likely to result in which wrist condition?

Answer 12

Guyon’s Canal syndrome

Question 13

What type of fracture is this? What patient demographic is it most common in?

Answer 13

Greenstick fracture: occurs when a bone bends and cracks, instead of breaking completely. The fracture looks similar to what happens when you try to break a small, “green” branch on a tree.

Most occur in children younger than 10

Question 14

What type of fracture is this? What patient group is often seen in? What type of force causes it?

Answer 14

Torus fracture, also known as buckle fracture → incomplete fracture of shaft of a long bone that is characterised by bulging of cortex. They result from trabecular compression due to an axial loading force along the long axis of bone

children

Question 15

Scaphoid fracture is have a high false negative x-ray rate. Which symptom should be treated as a scaphoid fracture?

Answer 15

Pain in the anatomical snuff box