What exactly does it mean when an MRI reveals "heat" spots and how is that different from a stress fracture? I certainly had no idea, so before Saturday's game against Charlotte, I sat down for a few minutes with J.J. Bush, the Maryland basketball team's athletic trainer, to try to gain some clarity.
Bush said physical stress on bones and tendons in the human body has a similar result to repeatedly bending a coat hanger back and forth.
"After you bent it for a while and you put your finger on it, the metal would be hot, just from the stress," Bush said. "If you continued to bend it, then it would probably break. So the first part, the stress reaction, is a definition within itself. It's a reaction of your body to stress. It could be a muscle, could be a bone. In this case, we're talking about bones."
Bush said bones react to mounting physical stress by becoming thicker. There are cells called osteoblasts, which are designed to help build up the bone. There also are cells called osteoclasts, which have the opposite intention of breaking down the bone. Both types of cells are at work at the same time, and as long as there is a balance, no problem exists.
However, if the stress is greater than the bone can withstand, that's when the body starts developing what Bush called "heat action."
"It's when the stress is too great that the body can't rebuild the cells at the same rate," Bush said. "So that's like the coat hanger, if you keep bending it and bending it, it gets hot and that's a reaction to the stress you're putting onto the wire. If you continue to bend it, if you don't reduce the stress or stop the stress, and you continue to bend the wire, then it's going to break."
Typically, Bush said, stress fractures begin as stress reactions (or "heat spots," as they are revealed on MRI exams). The goal, then, is to eliminate the stresser, be it running, jumping or whatever physical activity is the source of the repeated pounding.