Multifocal osteonecrosis revealing an antiphospholipid syndrome: Case report

Abstract

Multifocal osteonecrosis is rare. A zone of epiphyseal bone-marrow necrosis of three or more joints characterizes it. The most common risk factors are glucocorticoids intake and alcoholism. However, there is a series of other causes that could be incriminated in osteonecrosis, among which antiphospholipid syndrome. This case report, illustrates a primary antiphospholipid syndrome with only one clinical manifestation: multifocal osteonecrosis. A 30-year-old woman, with a medical history of left total hip replacement (THR), presents with severe right coxalgia and pain in both knees and shoulders. Clinical examination shows right hip severe mobility restriction. A hip radiography and a bone scan ordered to complete the diagnostic, revealed a severe multifocal osteonecrosis of the right hip, the two femoral condyles (at fracture stage) and the two shoulders. Dosage of the antiphospolipids antibodies showed an increase presence of anticardiolipin antibodies in two blood tests performed at a 12-week interval, thus confirming a primary antiphospholipid syndrome diagnosis. Antiphospholipid syndrome must be mentioned as a possible cause in a small number of patients presenting with osteonecrosis, without presence of any major risk factors (as glucocorticoid intake or alcoholism), even without any history of blood clots or miscarriages. Some data suggest that the introduction of an anticoagulant treatment at early stages of osteonecrosis of the femoral head would delay the progression of bone collapse and would prevent the appearance of new bone lesions.