Why am I experiencing pain, warmth and swelling in my knee 11 months after a total knee replacement?

3 basic possibilitie. Major long-term problems that are associated with total knee arthroplasty include late. 1- infection. 2- wearing of the bearings, and loosening of the prosthesis. 3-periprosthetic fracture and arthrofibrosis may also occur but are less common.
Uncertain. While mild swelling and slight warmth in the knee may remain or be intermittent at 11 months, in most cases it has resolved by then. Pain is relative and if it is still improving, it may be okay. If pain and swelling are increasing, you should return to see your surgeon for an examination and x-ray. He will tell you if further testing is necessary.
Not normal. Pain, warmth and swelling are all clinical signs of inflammation. These symptoms are quite normal for up to 9 months following knee replacement surgery. If these symptoms are present in your knee, replaced 11 months ago, it could be a sign of potential problem. You should be re-evaluated by your orthopaedic surgeon.