Bone marrow edema of the femoral head.

This article addresses the MR features of the bone marrow edema syndrome (BMES) of the femoral head with emphasis on the prevalence and clinicopathology of the disorder and description of the current concepts on diagnosis and prognosis. BMES can be observed in self resolving conditions such as transient osteoporosis of the hip, spontaneous fracture of the femoral head, or post traumatic lesions. Rapidly destructive coxarthrosis, necrosis of the femoral head as well as certain forms of spontaneous fracture of the femoral head may present a similar MR pattern, though prognosis is definitely less favourable. The challenging role of the radiologist is to recognize BMES at an early stage and to provide adequate prognosis on the lesion outcome.