I had a lump on my left knee for about 4 years. my doctor had said it was temporary, probably a cyst. It didn't grow in size and there wasn't really pain involved with it, unless the knee swelled. I was squatting down the other night, felt a pop, now the lump is gone but there seems to be an almost varicose- like quality to what may be a vein or tendon below the knee, to the right of where the lump was, and it has the same hardness to it that the lump had, only in a slightly size. What could this be?