@johnbishop : good job on the lunge! I tried it, without holding onto anything, and I can easily make my back knee reach the floor - either one. I don’t think it has anything to do with being able to flex the knee. I really don’t know my official flex # either, but when I start out flat on my back, bending both knees as much as I can, then get into a sitting position to go compare positions, the TKR leg heel ends up 2” farther away from my butt than the other one, so also a pretty decent bend. Lucky you found knee pads that work for you. I haven’t, not for lack of trying. Indoors a small pillow, or folded up bath towel, will work. Outdoors - forget it.
@saeternes : congratulations on your remarkable results. I also scaled down the exercises after 6 or 7 months, since with walking and/or swimming, and the usual household and garden chores I figured the knee gets enough of a workout. Regarding the catch in the knee when bending, I hope it goes away. I have had a very audible crack - no pain - whenever I do this exercise. One of a series of movements I was told to keep my sciatic nerve from acting up. Not a pleasant sound, but supposedly harmless. I rely on my other knee as well to quickly get up or down, but about 3 weeks ago I have started to have intense, acute pain on the outside of the “good” knee whenever a certain spot touches the floor when rolling onto that side, or when I kneel and shift my weight to the outside of the knee. Perhaps a growing bone spur - have not yet found the courage to head to a doctor’s office. That would surely be a bummer, if I get limitations on both sides now!