Breaking a bone is not uncommon. If you're on a hiking trip and a companion breaks a bone, splint the area for stability, then seek medical attention. Don't try to reset the bone yourself, which could cause further injury. However, if you're days from civilization or there is a serious problem (the break is causing extensive bleeding or pressure on an artery; or fingers and toes are numb, indicating nerve pressure), here's how to set a bone:
First, apply traction. When a bone breaks, the surrounding muscles generally contract, which often pulls the bones out of alignment. So if your buddy broke his lower leg, get a good grip on his foot and slowly, firmly, pull it toward you for several seconds. Make sure you're pulling in the same plane as the broken bone. That is, pull the bone in a straight, even motion, not at an angle. And don't jerk while pulling. When it appears the bone is in place, keep a firm grip while someone else splints the bone in place. (Ideally, the splinter will be a third party, not your injured friend.) Then you can gently release your grip [source: Hubbard].
To splint a bone, use something rigid, like sticks, board, or rolled up blankets, to put on either side of the injured body part. Make sure the splint extends beyond the body part. Tie the splint to the body part with rope, a belt or other material. Make sure it's not too tight to cut off circulation [source: Medline Plus].