Sorry, didn't get back right away, I didn't think anyone was going to respond. Good advice here, much appreciated. I'll look for that book. I hate being stupid. Ask me how I know being stupid is not good.
In the short run, went to a sports med place today, just using regular plan B. Doc says no surgery is needed, though maybe in a few years I'll want artificial knees. Just creeping arthritis now. Who woulda thought? Way too much basketball on concrete courts when I was younger.
He gave me a steroid injection in both knees, both have been hurting off and on but the recent event was the worst I've had with a knee. Feel better already. Maybe I can make it to that soft retirement teaching math and then get new knees one summer.