I had a meniscus removed when I was in high school because of a middle school football injury. Ripped the ACL in that knee later ... probably high school... it's been resorbed. I've done pretty well for most of my life but gradually I gave up sprinting, then jogging, then any sort of activity that required sudden explosion involving my left leg. But I was fine walking and riding my bike ... my favorite exercise anyway. Now cycling hurts. I'm going to try another round of hyaluronic acid but maybe it's time for a new knee. My orthopedist was showing me a model ... talking about how it would tighten my ligaments, restore spacing and cushioning. Honest to God, watching it operate in his hands reminded me of my feelings the first time I saw a Datsun 280Z Pass me on the highway... a combination of excitement and desire. Anybody here had experience with a new knee?