The idea of something breaking in our bodies brings immediate thoughts of pain to mind. It is like hitting the funny bone, which is not a bone at all. When nerves are injured, we expect to have pain. But bones do not have nerves. It is not the actual broken bone that is causing the pain, but other structures around the bone.
Bones have a thin, film-like covering called periosteum.
This covering is one of the structures surrounding the bone that has nerves, lots and lots of tiny nerves fibers. But that is not the only reason why it hurts to break a bone. Other structures around the bone are muscles and layers of skin tissues. These structures also have lots of nerve fibers and are designed to hold a certain amount of body fluid. The body fluid contains the chemicals our body uses to fight off infection and to heal injured areas.