On my ship the majority of passengers are senior citizens and retirees, tons of them with hip/knee replacements, I've talked with many of them just out of general curiosity. I've never had a passenger tell me that they regret having the surgery, especially ones with knee replacements. Just putting in my two cents. Obviously I would try every route possible besides surgery, but stem cells are expensive and not covered by insurance. I remember somebody telling me once you have one body for your whole life, imagine if you had one car for your whole life, how good would you take care of that car knowing that is your only mode of transportation forever? So in this metaphor it like you are driving a car with a flat tire. Quality of life is everything dude, you are saying you can't even enjoy a nice walk with your dog on a beautiful evening in Hawaii, if I was in your position, I'd definitely go for the surgery bro. Rehab that shit and go out and enjoy life!