Migrating bone marrow edema syndrome: a cause of recurring knee pain.

Bone marrow edema syndrome is a condition of unknown etiology, presenting with painful limping. It is characterized by normal radiographs, but magnetic resonance imaging findings change with bone marrow edema. When there is osteopenia in the radiographs, the condition is called transient osteoporosis. The term migratory bone marrow edema syndrome is used when there is involvement of another joint, or another compartment in the same joint, which typically occurs within 6 months of onset of primary symptoms. Here, a case of migratory bone marrow edema syndrome in a 47-year-old male patient, which was conservatively managed, is reported.