Bone grafting is done for injury and disease, as well as a number of different reasons, including. The four main reasons include: Complex Fractures: In many cases, a bone graft is used to treat multiple or complex fractures including those that do not heal well after initial treatment. Fusion Treatment: Fusion, which is a type of bone graft that helps two bones heal together across a diseased joint, is most often done on the spine to help the vertebrae heal faster. Regeneration: For bone lost to disease, infection, or injury, regeneration may be used, which typically involves using large sections of bones or small amounts of bone in bone cavities. Surgically Implanted Devices: In addition to this, a bone graft can be used to help bone heal around joint replacements, plates, screws or other surgically implanted devices.