Hand fractures

Question 1

Causes of scaphoid fracture?

Answer 1

• FOOSH with radial deviation at wrist
• Contact sports
• RTA with patient holding steering wheel

Question 2

Epidemiology of scaphoid fracture?

Answer 2

• Male:female - 7:1
• Average age is 22 (range from 9 to 35)
• 12.4 per 100,000
• Peak incidence in autumn (children returning to school sports)

Question 3

Presentation of scaphoid fracture?

Answer 3

• Pain on radial aspect of wrist and base of thumb
• Loss of grip and pinch strength

Question 4

What signs are 100% sensitive and 74% specific for scaphoid fracture?

Answer 4

• Pain and tenderness of anatomical snuffbox
• Telescoping pain
• Tender scaphoid tubercle

Question 5

Investigation for scaphoid fracture?

Answer 5

• AP and lateral X-ray immediately
• AP and lateral X-ray in 2 weeks if scaphoid fracture confirmed or highly suggestive clinical signs present (X-ray may initially be normal)
• CT scan if planning operation or checking fracture union
• MRI definitive to confirm or exclude (usually used as second line imaging)

Question 6

What is the management of scaphoid fracture?

Answer 6

• Undsiplaced: wrist immobilised in neutral position in POP cast until radiological evidence of union (6 weeks to several months)
• Displaced, proximal scaphoid pole or symptomatic non-union: surgical fixation with bone graft and screw insertion

Question 7

What is a Bennet’s fracture, what causes it, and what does radiology show?

Answer 7

• Intra-articular fracture at the base of the thumb’s (1st) metacarpal)
• Caused by forced hyperabduction of the thumb
• X-ray shows triangular fragment at base of first metacarpal

Question 8

What is a Boxer’s fracture, what causes it, and what does radiology show?

Answer 8

• Intra-articular fracture at the distal end of the little finger’s (5th) metacarpal bone
• Caused by impact on a flexed MCP joint/clenched fist (fist fights, punching wall)
• X-ray shows fragmentation of distal portion of 5th metacarpal

Question 9

What nerve damage is associated with lunate fracture?

Answer 9

Median nerve damage

Question 10

What carpal fracture is associated with median nerve damage?

Answer 10

Lunate fracture

Question 11

Metacarpal fractures?

Answer 11

• Common
• Important they don’t unite poorly or with malrotation as this will affect finger flexion
• Normally heal with simple strapping

Question 12

Why is the lunate less likely to dislocate?

Answer 12

• The lunate is firmly attached to the distal radius by ligaments and is known as the keystone of the carpals
• Therefore dislocation is severe

Question 13

Lunate dislocation?

Answer 13

• Lunate dislocates dorsally but rest of carpals stay aligned
• Less common but more severe

Question 14

Perilunate dislocation?

Answer 14

• Lunate remains in place but one of the other carpals dislocates
• More common but less severe

Question 15

What are the clinical signs of carpal fracture?

Answer 15

• Wrist pain following trauma
• Palmar wrist often swollen and can cause acute carpal tunnel
• Pain on extension of fingers so fingers stay flexed