RESUMEN
Avascular osteonecrosis of the femoral head (AONFH) usually goes through the four stages described by Arlet and Ficat: normal radiographs, heterogeneity and sclerosis of the femoral head, subchondral fracture with an individualized sequestrum, and secondary osteoarthritis. Arlet and Ficat individualized a specific pattern of AONFH which they called ischemic hip disease, in which cartilage damage seen as concentric joint space loss precedes the bony alterations. Although radiological and pathological studies of ischemic hip disease have been published, no clinical data are available. We report the case of a 65-year-old man admitted for a 1-month history of severe hip symptoms with concentric joint space loss but no osteophytes. Laboratory tests and examination of fluid aspirated from the hip ruled out septic arthritis and inflammatory hip disease. Two magnetic resonance imaging (MRI) studies done 1 month apart showed diffuse edema involving not only the femoral head but also the neck and trochanter, as well as major synovial hypertrophy. This atypical MRI appearance prompted synovial membrane and pertrochanteric core biopsies, which showed reactive synovitis and stage IV osteonecrosis, respectively. The pain, disability, and joint space loss worsened. Total hip arthroplasty was performed 1 month after the biopsy. Histological examination of the femoral head showed diffuse necrosis; no evidence of another condition was found on histological sections of the entire synovial membrane. This case corroborates the hypotheses put forward by Lequesne that some cases of rapidly destructive hip osteoarthritis may be ascribable to ischemia.