Legg–Calve–Perthes disease

♦ Avascular necrosis of the femoral head initiated by unknown factors is followed by gradual restoration of blood supply and regeneration ♦ Current treatment methods aim to prevent development of an aspherical and incongruent femoral head and acetabulum ♦ Treatment should be offered to the child with a poor prognosis so that the natural history of the condition can be improved: identification of such cases is difficult ♦ Early and late management strategies differ significantly.