26T, Check out other options before going with a replacement. Over five years ago I was in the place your in right now. Told I need to get a total knee replacement. The surgeon was the same guy that worked on me from my motorcycle accident in the mid 70's, later did a couple of clean ups and finally declared it ka-put. But as he said, keep in mind a replacement has a life expectancy of 17 years in ideal conditions, a whole lot shorter if your work, or play for that matter requires you to get up and down repeatedly, kneeling, etc. (Being a mechanic, that's exactly what I do.) Instead we tried a cortisone injection first, that did nothing for me, no pain relief at all. Tried the Synovial Fluid injections next. A series of three injections done a week apart. The first time it lasted about 9 1/2 months. No pain at all, the crunching was gone, it stopped catching and hanging up, I was doing quite well. I went with it a second time after a month or so of increasing discomfort. This time was just a successful, only a lot longer, 3 1/2 years this time, will be 4 this April. Synovial fluid is a compound our bodies make naturally in the joints. As we get older the amount made decreases to the point where there isn't enough to lubricate the sliding parts of the joint any longer. If you go with a replacement and wear it out in three years, you can only repeat the process one more time. And that will be what you get to live with for the rest of your days. Synovial injections don't come with a guarantee, but the success rate is pretty darn good. If nothing else at least check it out, it may buy you some time.