Avascular femoral head necrosis (AFN) is an uncommon complication of acute lymphoblastic leukemia (ALL) occurring in association with serious functional late effects. One of the many risk factors is high-dose corticosteroid therapy.
Case report: Three children belonging to a series of 266 patients developed AFN. The diagnosis was not made immediately when X-rays were normal. In spite of the fact that treatment was begun as soon as possible, the three children had a difference in the length of their legs, with reduction of their walking perimeter and, in one case, an arthroplasty was necessary.
Conclusion: If some patients treated for ALL limp or suffer when walking or when practising sports, the diagnosis of AFN is to be evoked. The diagnosis is not only based on simple X-rays but also on magnetic resonance imaging, which is more sensitive and reveals lesions earlier. The treatment consists of immobilization of the hip, whether or not associated with surgical procedures.