
09/27/2025
Breaking a bone is a big deal, but you already knew that. What you may not know, though, is what happens after the break: the four-stage healing process that our bodies undergo to fix the break.
Hematoma formation, or blood clot formation, within hours of the break. Blood vessels disrupted by the break flood the area and form a clot, which serves as a temporary structure to support the break. The hematoma also attracts immune cells that remove dead tissue and cause new tissue growth.
For the next 1-3 weeks, soft callus formation takes over. A protein called fibronectin, along with other growth factors, go to the break area and begin forming new soft tissues and blood vessels.
Bony callus formation is next, lasting several months. Osteoblasts (new bone cells) are made and fill in the bone matrix in each side of the break, eventually forming together to support the soft callus and overall bone structure.
Bone modeling finalizes the process in the years after the initial break. This process involves layering newly formed bone with older bone, absorbing tissue and replacing it until the bone is fully healed and regains its function.