My healthy 29 year old athletic son was tripped while running in a baseball game. He got up and verybwuickly developed a large golf ball size swelling on the outside of his shin, in the muscular part next to the shin bone. No pain, a lot of pressure. He iced it, elevated and rested for a day. The swelling is down today but he has now been told by an MD that it is a “decent sized hematoma outside the muscle towards the surface”, and to continue icing it, but elevation not necessary. It is not at all black and blue, and the MD said that my son’s body clearly processes something like this differently from most people. MD said my son’s planned 5 hour flight in 3 days is ok. Any other treatment recommended to help this go away and minimize any issues while flying? Arnica?