The surgeon replaced the entire femur due to an osteosarcoma. He disarticulated the femur at the hip joint and at the knee joint and replaced the entire femur with a prosthesis. I am not finding a code for this procedure. The only thing I find is a hemiarthroplasty of hip and a knee arthroplasty. He didn't cut the femur, he disarticulated and replaced. Any help is greatly appreciated.