Scaphoid Fracture

SCAPHOID FRACTURE

• Fracture scaphoid accounts for 60% of carpal injuries.
• More common in young adults.
• Rare in children and in elderly people.

Mechanisms of Injury 

• Two mechanisms are described:

1. Radial compression and dorsiflexion occurring at the wrist during a fall on an outstretched hand.

• Results in an undisplaced fracture.

2. Hyperextension occurring at the wrist during a fall on an outstretched hand.

• Results in displaced fracture scaphoid.

→ Undisplaced fractures are less complicated than displaced fractures.

Classifications

A. Based on Mayo classification:

1. Fracture of the tuberosity
2. Fracture of the distal body
3. Fracture of the waist (m/c)
4. Fracture of the proximal pole
5. Osteochondral fracture

B. Based on Russe classification:

1. Stable
2. Unstable

Clinical signs that help in diagnosis 

• Tenderness in the anatomical snuff box.
• Tenderness over the scaphoid tubercle 
• Scaphoid compression test 

Painful limitation of movements of wrist and thumb. 

Radiological views taken to diagnose fracture scaphoid

1. Standard PA view of the wrist (with wrist in dorsiflexion and ulnar deviation after making a fist)
2. Standard lateral view.
3. Radioulnar oblique view in midprone position.
4. Stress views only if needed (Stress view opens up the fracture site).

Interpretation of the radiograph:

Scaphoid fracture is generally identified as:

1. clear lucent line across the bone.
2. distinct break in continuity.
3. A distinct sharp step.

Complications of Fracture Scaphoid

• Nonunion
• Avascular necrosis 

Radiocarpal degenerative arthritis  

Exam Important