Abstract
Lipoma arborescens is a rare and benign intra-articular lesion characterized by a lipomatous proliferation of the synovial membrane, usually affects the knee joint. It presents as an unusual cause of intermittent knee pain and joint effusion. We report a case of lipoma arborescens of the knee in a 23-year-old man that initially resembled inflammatory arthropathy. The diagnosis of Lipoma arborescens was made by magnetic resonance imaging of the knee and confirmed histologically by synovectomy. The purpose of our case is to show the imaging features enabling early diagnosis and appropriate treatment.