Lipoma Arborescens is a rare, benign, intra-articular lesion, of unknown etiology, characterized by villous proliferation of the synovium and diffuse replacement of the subsynovial tissue by mature fat cells. It forms part of the differential diagnosis for a slowly progressive chronically swollen joint. We present a case of bilateral involvement of the knees and discuss the symptoms, diagnosis and treatment of this condition.
Arborescens; synovial membrane; knee