What is the first stage in the healing of a bone fracture?

• A. Hematoma forms
• B. Fibrocartilage callus forms
• C. Bony callus forms
• D. Bone remodeling

Answer: (A)

Immediately after a fracture, bleeding from torn vessels creates a hematoma at the break. This clot seals the damaged vessels, stabilizes the fragment ends, and fills the area with blood that brings inflammatory cells and growth factors. Those signals initiate the cleaning of debris and begin recruiting cells that will lay down the early scaffolding for repair. This hematoma sets the stage for the next steps, where a soft fibrocartilaginous callus forms to bridge the gap, then a hard bony callus forms as new bone is laid down, and finally remodeling reshapes the bone. So the first stage is the formation of the hematoma.