I believe you have to be a certain age before you can have a total replacement. Maybe the docs are afraid you'll wear it out IF done too early in life. I know my doc said that to me when I had mine done at 61. Sorry for what you are going thru but for the last 6 years prior to my replacement, I worked at a USPS package processing facility. Going up and down ladders and working on the processing machine after 'suffering' a sideswipe by a cage while on my bike. Strong enough to break off my Harley carb, which my knee was resting against. Needless to say, my right knee ligaments were ALL torn. (AND I was TOO YOUNG for a replacement at the age of 55).I wish they would let me get a total knee replacement. But docs say no. Multiple I've gone to. I'm 36. Pain every day, it's brutal.