What are two body systems that are used to heal a broken bone?

Answer: How Do Bones Heal? In the first few days after a fracture, the body forms a blood clot around the broken bone to protect it and deliver the cells needed for healing. Then, an area of healing tissue forms around the broken bone. This is called a callus.

The injury triggers the body to release fat from healthy bones. The red marrow in the fractured bone releases fat to heal the fracture.