What are the four stages of fracture healing?

What are the four stages of fracture healing?

Fracture healing is mainly divided into four stages: hematoma organization stage, scab formation stage, bone healing stage, and fracture remodeling stage.

1. Hematoma Organization Stage

When a fracture first occurs, tissues such as the periosteum, bone, and bone marrow will be damaged or broken, affecting the small blood vessels around the bones, leading to ruptured blood vessels and bleeding, blood circulation disorders, hematomas, and pain. In the early stages of a fracture, local bleeding is severe. About 4-5 hours after the injury, the blood at the fracture site begins to gradually coagulate, forming a blood clot containing reticulin. Afterwards, the hematoma will stimulate the affected area and promote the regeneration of capillaries, phagocytes, and fibroblasts. These regenerants will invade the blood clot and necrotic tissue from all directions to form granulation tissue, which is then further transformed into fibrous tissue to connect the fracture ends, which is the hematoma organization stage.

2. Callus formation period

Callus is a layer of periosteum on the surface of bone, which plays an indispensable role in promoting bone growth and regeneration. Generally, one week after a fracture, osteoblasts in the periosteum will begin to divide and proliferate in large numbers, forming new bones, promoting the formation of fibrous tissue, and connecting the fracture ends. It will be completed in about 4-6 weeks.

3. Bone healing period

The bone healing period is about 8-12 weeks after fracture. During this period, new bone beams in the scab gradually increase, and the bridge scab of the fracture gap will be completely ossified. In the X-ray image, it is manifested as the disappearance of the fracture line, the increase of bone density, the filling of the medullary cavity by the scab, and the gradual blurring of the boundary between the scab and the cortex, which is the performance of the bone healing period.

4. Fracture Remodeling and Shaping Period

The fracture remodeling period is the final stage of fracture healing and a critical period for the recovery of bone morphology and structure. It is mainly reshaped through the process of osteogenesis and osteoclastology to restore the original state and function.

Fracture healing is mainly divided into four stages. The injury conditions at different stages are different, and the treatment and care methods will also be different. In terms of treatment, it is best for patients to adopt staged treatment and staged care, which can promote injury repair and shorten the course of the disease.