I had a left knee replacement - osteo arthritis and related to a sport injury.  I was assaulted and the replacement was damaged. I had a second left knee replacement. About 6 months later the knee started swelling up. GP diagnosed it as gout, and treated it with gout medication. These flare ups happened more and more  frequently and increased in severity, especially after having a left hip replacement. GP twice treated with steriod (cortisone)injections. Before injecting the cortisone, the GP drained blood from the knee joint. Had relief but only for short period. GP then referred me to orthopeadic surgeon again. After X rays, ultra sound (which indicated that I had a bursar and baker’s cyst as well as extensive fluid on the knee), nuclear (bone and gallium) tests, nothing showed up. Surgeon surmises that the plastic disc that forms part of the prothesis, may be breaking up in microscopic particles He suggested that I go for another operation and get a hinge prothesis I looked at a photo in the brochure, and noticed that there is also a plastic disc My question is therefore - if the current plastic disc is disintegrating, isn’t the possibility that this will happen again? It seems as if the body rejects the plastic disc. At the moment I am using Codalgin Forte (500mg paracetamol and 30mg codeine) I am very reluctant to have the operation BUT also feel I can’t go on like this as these flare ups can happen any time and compromises my day to day living. During such a flare up I can’t walk, sometimes for a couple of days. I lie in bed with cold compresses on the knee! I will appreciate any advice.

Summarized question: What is the probability that a plastic disc in a hinged knee prosthesis will disintegrate?