snow: not sure I understand your question, but see if this clarifies.
Kneeling became worse and worse, over time, as arthritis damaged my knees. Walking/working on my feet was difficult and got worse. When I reached the place where I couldn't work without enough Ibubruphen to destroy my liver, and couldn't use opiate pain-killers (random testing for work, beside not wanting to get hooked.) the surgeon said the only answer was a TKR. (Total Knee Replacement). That allowed me to work at least 4 more years, got to the minimum retirement age. Then there was nothing more they could do. However, kneeling was uncomfortable, but not all that bad.
Knee replacements aren't all they are cracked up to be. Some people do "fine". Tell me: it's plastic & metal, so how could it hurt? But it does, for me. The P.T. is extended and notmuch fun, but necessary. They hand you a broshure before operation that makes/says recovery is like a walk in the park. Liars.
When I got my first one, I wondered why I hadn't do it earlier - years before I did get one. I know guys who got hip replacement and wondered the same thing and worked many years after getting one done.
Okay, then, after 2 years, the 1st one failed, but the doctor wouldn't believe me until about 1 3/4 years. They did the x-rays and said, "Oh. Yeah. Your replacement went bad." They had glued the replacement in, and the glue failed. Nice. They gave me the one they took out as a souvenier.
Second replacement on that same knee: got infected, I went into septic shock, total life support, 10 days in the ICU. In 2013. They took me off life support at day 11 to see what would happen. Then they stuck me in a regular ward. 3 days. Then warehoused me in a nursing home. A couple months & they hadn't cured the infection. An infectious disease doc took one look and said that artificial knee had to come out NOW. The next hospital took out the knee, replaced it with cement knee loaded with antibiotics. 6 weeks on more IV antibiotics and they said "it's cured". The 2nd hospital proceeded to replace the cement knee with a "real" TKR. Here I am today. The other knee has been replaced.
Oh. In case you are wondering, I spent much of my life on vibrating steel decks, which are harder on the body than cement floors. Arthritis has damaged more than my knees.
So, I confess. I'm a horse. Needed 4 knees.
I was just down in the crawl space. Even with soft things to kneel on, it is - at the least - very uncomfortable. Also hard to get up.
Sorry about the length. Did I answer the question?