There are several potential causes for painful knee replacements, including:
The knee replacement parts may become loose, leading to persistent pain. This loosening often occurs after you've had the implant for a long time – years or even decades.
BY FAR the most common example of this is from nickel sensitivity and metal sensitivities are THE MOST COMMONLY missed cause for painful knee replacements though they may account for over 50% of the ones that are not infected. We are always thinking about this and test for it. Even that problem can usually be resolved. (It is surprising how many people can’t wear costume jewelry, for instance, and it never comes up prior to having their knee replaced and then the knee replacement recovery doesn’t go well. In our office we actually ask about that prior to surgery and if there is doubt we use a ceramic bonded implant).
This can be ruled in or out with specialized X-ray, radiologic scans, or lab tests.
Patellofemoral (kneecap) problems
You may have less than perfect kneecap function following knee replacement surgery, as your kneecap has to bear a significant strain.
If the alignment of your implant isn't quite right, it can put pressure on the joints, nerves, and other tissues, resulting in pain.
An infection or fracture in the remaining bone could also cause painful knee replacements.
As an example, it is possible to have ONLY KNEE pain with hip osteoarthritis. We check for remote (so called “referred") causes of the pain.