Broken bone treatments are necessary to determine the severity of the injury and to assess the body for any other ailments. The treatments of bone fractures differ depending on many factors, including severity, location, and age. In many cases a splint or cast may be applied to help aid in the recovery of the bone. They keep the ends of the bone in a secure location and help the bone mend itself. Physical therapy may be one course of treatment following a broken bone. This type of treatment typically starts while the patient is still in the cast or splint. Traction is one method of repairing a severe bone injury. In this situation the bone endures tension using a pulley system with weights.