I have been using my knees in a different way at work lately, that I haven't really used before, and I'm sure that is why I am having my problem. I am a healthy 37 year old with no prior injuries, but now I have noticed a lump on the upper left side of my left knee. It doesn't hurt and it only protrudes when I am standing. Also, my joints in my knees are stiffer. I have been taking Motrin with some glucosamine/ chondroitan. What is it and will it go away. Please help.