Stretching, I've found is generally "Generally' the best thing I've found for rsd.
Once you've had a knee surgery all bets are off.
I talk to my neuro about it last visit, as I get cramps in my calves when I sleep.

Stretching the toes UP, (Toward your face) is the best way for that.

Be sure you're stretching correctly!

Try a 'Tai Chi' dvd, or book...

After stretching,, and only after stretching is the time to exercise.

Hope you're well!

Pete