Legg-Calve-Perthes Disease

  • Etiology: Idiopathic avascular necrosis of immature capital femoral epiphysis
  • Imaging: Course of disease divided into 4 stages
    — Stage 1 – Condensation
    — Stage 2 – Resorptive-fragmentation
    — Stage 3 – Re-ossification-healing
    — Stage 4 – Residual-healed
  • Imaging Radiograph:
    — Early see microfracture or subarticular lucency = crescent sign
    — Later see fragmentation of femoral head and subchondral cysts and coxa magna or coxa plana = enlarged or flat femoral head and femoral neck shortening
  • Imaging Bone scan: Changes present 4-6 weeks before radiographic changes
  • Imaging MRI: Femoral head has decreased signal intensity and decreased height and has fragmentation
  • DDX:
  • Complications: Early osteoarthritis
  • Treatment:
  • Clinical:
    — Seen in ~ 4-8 years old while slipped capital femoral epiphysis is seen in 13 years old
    — Bilateral in 10-20% and if bilateral usually affected sucessively and not simultaneously
    — Five times more common in males

Radiology Cases of Legg-Calve-Perthes Disease

Radiograph of Legg-Calve-Perthes disease and slipped capital femoral epiphysis
AP (above) and frogleg (below) radiographs of the pelvis shows the right femoral head to be flat and enlarged with femoral neck shortening. The left femoral epiphysis is slipped posteromedially.