Pain in a knee following a joint replacement can be caused by many different things. As you indicate, the best place to start is by evaluating the implant itself to make sure it is in the right place. It seems that your artificial joint is seated properly--a good thing to know--but also making it necessary to look for other reasons for your pain.
If you have not done so already, it is probably a good idea to make a follow-up with the surgeon
who performed your surgery. He or she can do an orthopedic evaluation of your entire joint to evaluate not only the implant but also the other ligaments, muscles, and bones that help stabilize the knee. Depending on the results of this exam, he or she may want to obtain further imaging to evaluate other parts of your leg beyond the joint replacement. Physical therapy may be an option as well, if it seems like the muscles of your knee are not balanced properly.
If you are still having significant pain after these evaluations, it may be helpful to see either a rehab medicine physician (called a physiatrist
) or a pain specialist. Some people can have neuropathic pain that develops post surgery and this can be managed by pain specialists