Why do I still have problems with my first tkr, now just short of 22mo. old? If I overdo, and that's an overstatement, it takes very little exercise to cause swelling and pain. I get a very painful "knot" just under the kneecap and to the inside on my left knee. This has happened several times over the past yr. I visited my ortho, took x-rays, all was fine. No reason he could find. Only guess he had is that it may be scar tissue and if it becomes a problem he can scope it to check for scar tissue. Does scar tissue flarup then get ok? So tired of this knee, right on that is just shy of one yr. is great, has been from the beginning. Frustrated! Anyone else have lingering issues with a tkr?