Most knee replacements provide very good long term function for many years after implantation. The most recent figures from The AOANJRR (Australian Orthopaedic Association National Joint Replacement Registry) reveal that the revision rate for Primary Total Knee Arthroplasty at 15 years is 7%. Most of these replacements have failed either as a result of infection or premature wear.
After a long period of time, a knee replacement can wear out. Sometimes the procedure to correct this problem is as simple as changing the polyethylene bearing insert in the knee – much like a retread on a car tyre. Other times a much more extensive procedure is required where all the major components of the knee are exchanged. Each of these procedures can renew the life of knee replacement for another 10-15 years.
Below is an example of a worn out polyethylene bearing which was able to be swapped out for a new one.
Another example of a much more extensive procedure appears below.
The decision as to whether to do the more minor operation or the larger one is best left to your specialist total knee replacement surgeon who will consider the pros and cons of each operation.