Has anybody ever heard of this pain problem?

I have had this pain off and on since 1993. It is pain behind my knees and inside my elbows where the veins are. It seems to come up when I am very tired or perhaps makes me very tired. I was younger then (of course!) and near an ideal weight.

Any input would be appreciated.

The inside the elbow pain is called golfer's elbow and the back of the knee pain is very common with arthritis. I would guess when I have them both at the same time, it is very tiring for me. Thank for answering my post.