Avascular Necrosis

Question 1

What contributes to the pathogenesis of avascular necrosis? Which bones are most commonly affected?

Answer 1

• Interruption of blood supply to the bone in those with a single blood supply
  
  • Vascular occlusion and hypercoagulability
  • Bone healing that prevents revascularisation
  • Mechanical stress
• Femoral head, carpals, talus, humerus

Question 2

How is avascular necrosis diagnosed? What are the principles of management?

Answer 2

• Imaging (MRI generally) or histology (gold standard)
• Medical management
  
  • Reduction in weight bearing
• Surgical management
  
  • Bone graft, arthroplasty