Painful hot knees while I'm asleep

I have knee pains throughout the day, especially when I go up and down the stairs, but the most curios problem I have is my knees feel as though they are on fire while I am asleep, accompanied with pains. I can't stay a sleep and exhausted - sticking my knees out of comforter and exposed my knees to chilly environment (it's winter already) somewhat helps but I have to do this several times a night. Then I am off to work with not much rest.

I've tried to search this topic - I also ran this issue with my primary care physician but she thinks it is arthritis, but I don't feel as bad once I am up and around (vertically). I have pains while I am up and around but I’ve never had that “burning”, “my knees on fire” sensation unless I am completely horizonal, asleep. My knees don’t look swollen or red, every.

Do you have a clue?
Thanks,
ennya

Do you keep your home windows closed or slightly open? Its important to keep the air flowing as it counters heat and pain. It probably hurts less when you're moving as the amount of air you get increases when moving. Its also important to stay hydrated. Basically windows slightly open to let in air (especially when heating is on) and drink water to satisfaction level. Hope this helps.

My husband also has the same as Ennya, he had double knee replacement surgery and was fine for around 6 months, then he started to get really hot knees and he says he feels as though he is boiling or on fire. He too has to sleep with his knees out of the blankets and no one can help us. We wondered if it was due to nerve damage after surgery but it appears there are quite a few people with this problem. I cannot see what keeping the windows open will do, it may cool them down, BUT WHAT IS THE CAUSE AND THE PROBLEM, people with these symptoms need help.
Susan