Recognising scaphoid fractures is particularly important given the unusual blood supply of the scaphoid bone. Around 80% of the blood supply is derived from the dorsal carpal branch (branch of the radial artery), in a retrograde manner. Interruption of the blood supply risks avascular necrosis of the scaphoid, with this most commonly complicating proximal injuries.

Causes

• Falling onto an outstretched hand (FOOSH)
• Contact sports: The peak incidence during the autumn is thought to correlate with the start of football and rugby activities at school.

PC

Patients typically present with:

• Pain along the radial aspect of the wrist, at the base of the thumb
• Loss of grip / pinch strength

Signs:

• 1. Point of maximal tenderness over the anatomical snuffbox
  • This is a highly sensitive (around 90-95%), but poorly specific test (<40%) in isolation
• 2. Wrist joint effusion
  • Hyperacute injuries (<4hrs old), and delayed presentations (>4days old) may not present with joint effusions.
• 3. Pain elicited by telescoping of the thumb (pain on longitudinal compression)
• 4. Tenderness of the scaphoid tubercle (on the volar aspect of the wrist)
• 5. Pain on ulnar deviation of the wrist

Investigations

• X-rays (first week sensitivity - 80%)
• CT scan - May be requested in ongoing suspicion, pre-op or determining extent of fracture