Wrist

Question 1

Colles’ fracture definition

Answer 1

• extra-articular transverse distal radius fracture (~2 cm proximal to the radiocarpal joint) with dorsal displacement ± ulnar styloid fracture
• most common fracture in those >40 yr, especially in women and those with osteoporotic bone

Question 2

Colles’ fracture mechanism

Answer 2

FOOSH

Question 3

Colles’ fracture clinical features

Answer 3

• “dinner fork” deformity

* swelling, ecchymosis, tenderness

Question 4

Colles’ fracture investigations

Answer 4

• X-ray: AP and lateral wrist

Question 5

Colles’ fracture treatment

Answer 5

• goal is to restore radial height (13 mm), radial inclination (22°), volar tilt (11°), as well as DRUJ stability and useful forearm rotation

• non-operative
■ closed reduction (think opposite of the deformity)
◆ hematoma block (sterile prep and drape, local anesthetic injection directly into fracture site) or conscious sedation
◆ closed reduction:
1) traction with extension (exaggerate injury),
2) traction with ulnar deviation, pronation, flexion (of distal fragment – not at wrist)
◆ dorsal slab/below elbow cast for 5-6 wk
◆ x-ray at 1 wk, 3 wk, and at cessation of immobilization to ensure reduction is maintained
■ obtain post-reduction films immediately; repeat reduction if necessary

• operative
■ indicatio : failed closed reduction, or loss of reduction
Displaced intra-articular fracture
Comminuted
Severre osteoporosis
Dorsal angulation >5o or volar tilt >20o
>5 mm radial shortening
■ percutaneous pinning, external fixation, or ORIF

Question 6

Smith’s Fracture definition

Answer 6

volar displacement of the distal radius (i.e. reverse Colles’ fracture)

Question 7

Smith’s Fracture mechanism

Answer 7

fall onto the back of the flexed hand

Question 8

Smith’s Fracture investigations

Answer 8

X-ray: AP and lateral wrist

Question 9

Smith’s Fracture treatment

Answer 9

• usually unstable and needs ORIF

• if patient is poor operative candidate, may attempt non-operative treatment
■ closed reduction with hematoma block (reduction opposite of Colles’)
■ long-arm cast in supination x 6 wk

Question 10

Complications of wrist fractures

Answer 10

• most common complications are poor grip strength, stiffness, and radial shortening
• distal radius fractures in individuals <40 yr of age are usually highly comminuted and are likely to require ORIF
• 80% have normal function in 6-12 mo

Early 
Difficult reduction ± loss of reduction 
Compartment syndrome 
Extensor pollicis longus tendon rupture 
Acute carpal tunnel syndrome 
Finger swelling with venous block 
Complications of a tight cast/splint

Late
Malunion, radial shortening
Painful wrist secondary to ulnar prominence
Frozen shoulder “shoulder-hand syndrome”)
Post-traumatic arthritis
Carpal tunnel syndrome
CRPS/RSD

Question 11

Scaphoid fracture epidemiology

Answer 11

• common in young men; not common in children or in patients beyond middle age
• most common carpal bone injured
• may be associated with other carpal or wrist injuries (e.g. Colles’ fracture)

Question 12

Scaphoid fracture mechanism

Answer 12

FOOSH: impaction of scaphoid on distal radius, most commonly resulting in a transverse fracture through the waist (65%), dstal (10%), or proximal (25%) scaphoid

Question 13

Scaphoid fracture clinical features

Answer 13

• pain with resisted pronation
• tenderness in the anatomical “snuff box”, over scaphoid tubercle, and pain with long axis compression into scaphoid

Tender snuff box: 100% sensitivity, but 29% specific, as it is also positive with many other injuries of radial aspect of wrist with FOOSH

• usually nondisplaced

Question 14

Scaphoid fracture investigations

Answer 14

• X-ray: AP, lateral, scaphoid views with wrist extension and ulnar deviation
• ± CT or MRI

• bone scan rarely used
■ note: a fracture may not be radiologically evident up to 2 wk after acute injury, so if a patient complains of wrist pain and has anatomical snuff box tenderness but a negative x-ray, treat as if positive for a scaphoid fracture and repeat x-ray 2 wk later to rule out a fracture; if x-ray still negative, order CT or MRI

Question 15

Scaphoid fracture treatment

Answer 15

• early treatment critical for improving outcomes

• non-operative
■ non-displaced (<1 mm displacement/<15° angulation): long arm thumb spica cast x 4 wk, then short arm cast until radiographic evidence of healing is seen (2-3 mo)

• operative
■ displaced: ORIF with headless/countersink compression screw is the mainstay treatment

Question 16

Scaphoid fracture specific complications

Answer 16

• most common: nonunion/malunion (use bone graft from iliac crest or distal radius with fixation to heal)
• AVN of the proximal fragment
• delayed union (recommend surgical fixation) • scaphoid nonunion advanced collapse (SNAC) – chronic nonunion leading to advanced collapse and arthritis of wrist

Question 17

Scaphoid fracture prognosis

Answer 17

• proximal fifth fracture: AVN rate 100%; proximal third fracture: AVN rate 33%
• waist fractures have healing rates of 80-90%
• distal third fractures have healing rates close to 100%

The proximal pole of the scaphoid receives as much as 100% of its arterial blood supply from the radial artery that enters at the distal pole. A fracture through the proximal third disrupts this blood supply and results in a high incidence of AVN/nonunion