A broken arm is a common injury. Counting all fractures, about one in every 20 involve the upper arm bone (humerus). Children are more likely to break the lower arm bones (radius and ulna). Falling on an outstretched hand or being in a car crash or some other type of accident is usually the cause of a broken arm. Most people know right away if their arm broke, because there may be a snap or a loud cracking sound. The broken arm may appear deformed and be swollen, bruised and bleeding. A person with a broken arm usually has:
- Extreme pain at the site of the injury.
- Pain increased by any movement.
- Loss of normal use of the arm.