Suspicion of Recurrent Osteosarcoma in a Patient with Pseudotumour Adjacent To the Endoprosthesis.

Purpose: Pseudotumor is a rare complication after arthroplasty, most often of the hip joint, in response to metal particles present in the implant. There are merely sporadic reports of pseudotumor in patients with bone sarcoma after sparing surgery with endoprosthesis implant. The aim of this study is to present the characteristic imaging features of pseudotumor.