My wife had both knees done with no trouble. That was about 15yrs. ago. The trick is do the therapy. Hers was at the PT place not a home therapist. I have a friend who can't put his socks on because of a stiff knee. She can easily cross her legs and wash her feet. They rented her a machine that worked her leg up and down electrically . She spent 8hrs. a day 7 days a week on her back with this thing running her leg in and out for the first two weeks after the surgery(she could even nap with it running) in addition to daily therapy for the first week or two and 3 times a week for a month after that.. You could set the degrees of bend on it. I didn't tell her but I added a few more degrees than they said at each angle change. She swears that thing is what gave her the flexibility. I don't think they use it anymore. Some folks around here just got sent home with a list of exercises to do and a home therapist stops in once a week.