My osteoarthritis does not stem from underusing my joints. It is the result of an athletic injury. Once I too was a hardcore runner. And then my weird knees rubbed against each other, and I have some floaters in my knee. Bone spurs, cartilage, things like that. I also injured my ankle in high school by jumping off a log and landing on my ankle, not my foot. That was exactly as painful as it sounds.
I have been really been missing exercise. Tonight I get to EASE back in. Guess what turns out to be the best exercise for osteoarthritis of the knee? Walking. But only half as much to begin with.
What else is recommended? Tonight I get to practice sitting down and standing up, and I get to stretch and tense a wide variety of muscles in my legs. There's also a fair number of leg lifts.
For the ankle, apparently the best thing I can do to strengthen is to stand on one foot. I'm also supposed to do some flexing exercises.
From here on out, it's going to be exercising, keeping at it. If it hurts, I may have to take a little time off, but overall, it's important to keep moving.
I just won't be running any marathons. Otherwise, I should be able to have all my range of motion return, and I have to keep at it.
If you need any links to ankle or knee therapy, let me know. I got 'em.