I would propose also it could be neuropathic pain...that is something I experience occasionally over various areas...I suppose the knees could get it also...

Debbie, you may be on to something there. I have severe neuropathic pain in my other leg; it's so severe that I have to have pain meds every night. The neuropathic pain has gone on for years, and has been gradually increasing so that now it encompasses my entire leg and foot.

The only thing is that this is an entirely different kind of pain in my knee. The neuropathic pain in my left leg is a severe, almost intolerable burning, whereas the knee pain (in my right leg) feels as if my knee were dislocated; it painfully locks up on me. Luckily it doesn't last more than a couple of weeks at a time, but it's pretty darn disabling when it does occur. That's why I wondered whether or not it's spasticity...