My natural knee is pretty weak, if I use it to go up steps I have to go up straight legged. I try not to use my new knee with every step. I'd like to hold off until next year at this time because as a teacher I didn't like missing so much teaching time in the middle of the school year, it's such an important time in first grade. But the year is almost over in May and and I would still have a bit of summer to enjoy in July and August. But when the knee gives out there's not much you can do. My OS said it's similar to your brakes going in your car, it just happens one day. But I'm not having to use Aleve or any other pain medication on a regular basis for my left knee yet. So I'm thinking that's good.