I was diagnosed with costochondritis (inflammation of the cartilage in the rib cage, caused by sever coughing, getting hit, even laughing) and I was put on a steroid to reduce the swelling. One evening I was massaging my aching side when I came across a lump
on one of my ribs
...I had never noticed it before. It's hard and smooth, and it feels like it's part of the rib, but it kind of sticks out, and it's not on my other side.