Intraarticular corticosteroids possibly leading to local osteonecrosis and marrow fat induced synovitis.

We describe a woman with recurrent synovitis in one or both knees treated with intraarticular corticosteroid injections and two 6-day courses of methylprednisolone tablets. She later developed osteonecrosis of her distal femora and proximal tibiae. Her course was complicated by persistent synovitis associated with a large quantity of necrotic fat in the joint fluid.