How to manage a mobile knee in a femur plasmacytoma patient?

Question

Hello doctor,

I would like to know an orthopedist opinion about my mother's situation. She had femur plasmacytoma 20 years ago and 4 prostheses, because she had many infections after the operations. She remained with her external popliteus paralyzed. Now, she began to feel his knee mobile, and she could not walk because of it. There are some noises too. A few doctors said she needs Megasystem-C Link prosthesis, which would totally replace her hip and knee. What is your advice? Is there any intermediate option, like replacing only the actual prosthesis and adding pieces of bone? We heard that, in case of choosing the Megasystem-C, that can lead to amputation. So, we are looking for a second opinion. I have attached the radiograph links, please check.

Answer 1

Hello,

Welcome to icliniq.com.

The entire femur seen is grossly osteoporotic and the knee is showing evidence of osteoarthritis though I could not see the knee in the AP view. She needs a knee replacement but with the large hip prosthesis and very weak bone stock, I would support the use of a total femoral replacement. This, in reality, would need the whole femur to be removed but is not equivalent to amputation. The knee would have to be a constrained variety of her knee ligaments.