Which stage of fracture healing involves remodeling woven bone into mature lamellar bone?

• A. Hematoma formation
• B. Soft callus formation
• C. Hard callus formation
• D. Remodeling woven bone into mature lamellar bone

Answer: (D)

Remodeling is the phase where the bone’s architecture is restored after the initial stabilization. After the fracture has been bridged and a hard callus forms with woven bone, remodeling gradually replaces that woven bone with mature lamellar bone. Osteoclasts resorb the irregular woven bone, and osteoblasts lay down new, highly organized lamellar bone in well-defined layers, re-establishing the bone’s original cortical structure and strength. This process can take months to years and is influenced by mechanical loading, aligning the new bone along stress lines.

Hematoma formation is the initial blood clot and inflammatory response at the fracture site, while soft callus formation creates a fibrocartilaginous bridge, and hard callus formation mineralizes the bridge with woven bone.