Can you elaborate on what the surgeon meant by "bone formation"? The metal prostheses can be designed so the bone grows into it. This is done when a patient has healthy (bleeding) bone. If the bone isn't healthy (osteoporosis), then bone cement isn't used.

The surgeon's comment may be that the bone is growing into the prostheses, normally a good thing.

It would help if you could elaborate on the nature of the pain. and 120 degrees of motion is a bit low but acceptable post TKR. Just need some more info from you.

Joe