There are many possible reasons for residual pain after getting a knee replacement. Surgeons don’t always know why some people continue to experience this type of pain. Here are a few known ideas as well as a few current theories.
The two broad categories of pain-inducing factors following knee replacement surgery are patient and implant. Patient anatomy (e.g., shape, location, or angle of the knee cap) and gait (walking) pattern are two contributing factors.
A proper match between the patient and the implant is also important. Using an implant that is too large for the patient is called overstuffing. Putting the implant in place with good alignment is essential to restoring full, normal, pain free motion.
Studies show a gradual reduction of knee pain over time following knee replacement. This can take up to one or even two years for some people. But in approximately 10 per cent (one in 10 patients) persistent pain is reported. And like you, many of those patients have good motion and function. It’s just the pain that decreases their satisfaction with the procedure.
You didn’t mention any other disturbing symptoms. There are some people who report crepitation (crackling sensation heard and/or felt). Further studies have been recommended to find out what is causing these residual symptoms.
In the meantime, don’t hesitate to go back to your surgeon for a follow-up visit. There may be something quick and easy that could help you. Perhaps you just need some help adjusting the walk you walk or a strengthening program for a muscular imbalance.
It could be your surgeon will know right away what the problem is and how to fix it. In some cases, revision surgery to change something is required so keep that in the back of your mind as a possible solution. You won’t know until you have your knee re-evaluated.