Idiopathic avascular necrosis of the femoral head

Epidemiology

Age: 4–10 years

Etiology

Pathophysiology

Avascular necrosis of the femoral head due to a mismatch between the rapid growth of the femoral epiphyses and the slower development of adequate blood supply to the area

Clinical features

• Antalgic gait (on weight-bearing leg)
• Pain in the hip or the upper leg, sometimes projecting to the knee
  • Insidious onset, pain may fluctuate depending on physical activity
  • Often exacerbated by internal rotation
  • FABER test (Flexion, ABduction, and External Rotation) might be positive.
• Restricted range of movement
• Contralateral involvement in ∼ 10% of cases

Diagnostics

Treatment