Hurt Rib

My husband hurt himself years ago (about 4-5 years ago) wrestling in high school. He was laying on his back and his opponent was on top of him. He was trying to turn and throw his opponent over him onto the mat when he felt his rib pop. This same thing happened a couple days later while wrestling again.  He told a doctor about it about a year after it happened and they said basically not to worry about it and it is just cartilage. However, his rib or whatever it is sticks out relative to the rest of his ribs and occasionally it hurts him. We aren't really in a situation where he can visit a doctor and were wondering if anyone knows anything we can do. If it was supposed to heal by itself it didn't heal correctly. Is there some exercise he can do or some way I could massage it to help with the pain? Or is the only option really only something a doctor could do? Thanks!