Yes, I can squat all the way down and push back up, just feel pulling and tension in the knee, not pain. If I have to hold the position longer (weeding etc) It's more comfortable to squat with my butt uplifted a bit and not go all the way down. If you have a good degree of flexion in your knees, you should be able to do it. As anything, you need to keep working on exercises and strengthening your muscles that do the actual work. If you don't at least occasionally keep working them intensely after your PT is done, you could go backwards on flexibility, as the saying goes, if you don't use it, you lose it! In September I will be two years out TKR for my right, and one year out for my left knee. Though they will never feel like my own knees, I am happy with no pain, and near original flexibility. You have to keep working at it, just having the surgery and then sitting back and expecting muscles and ligaments to miraculously go back to the knees of your youth without putting in exercise time on your own, ain't gonna happen!