Hi, After kneeling on the floor I felt pain in my knee and there was a hard lump the size of half a golf ball on the outer side of my knee cap. It did not hurt after it appeared (just when I knelt) and went away with some rest and ice. After forgetting and kneeling again there was pain again and the egg popped back out again. There is slight swelling around the outer side of knee cap when it is gone but the knee functions fine. Any ideas on this lump that appears after kneeling?