MR Imaging of Osteonecrosis of the Femoral Head with Rapidly Destructive Coxarthrosis

Purpose : In this study, we investigated the magnetic resonance (MR) imaging characteristics of rapidly destructive coxarthrosis (RDC) caused by osteonecrosis of the femoral head. Material and Method : We reviewed 11 hip MR images (10 patients) of osteonecrosis of the femoral head with RDC. MR findings of 11 RDC were compared with those of Ficat stage IV osteonecrosis of the femoral head as a control. Results : The MR findings of osteonecrosis, involving the entire femoral head, bone marrow edema in the acetabulum, intraarticular loose bodies on the inferomedial portion of the hip joint, and synovial proliferation were significant in RDC as compared with those of osteonecrosis of the femoral head only. Conclusion : Distinct findings of MR imaging in conjunction with plain radiographs could be used to facilitate diagnosis, treatment, and prognosis in RDC.