What is the first stage of fracture healing?

The first stage of fracture healing is the formation of a hematoma. This process occurs immediately after a fracture, typically within the first few hours. When a bone is fractured, blood vessels within the bone and surrounding tissue are damaged, leading to bleeding that collects around the fracture site, creating a hematoma. This hematoma serves several critical functions: it provides a scaffold for incoming cells, creates an environment conducive to healing, and initiates the inflammatory response that follows.

Inflammation is indeed a crucial part of the healing process; however, it occurs as a response to the hematoma rather than being the very first stage. After the hematoma forms, inflammatory cells infiltrate the area to help clear debris and prepare for the next stages of healing. Therefore, the formation of the hematoma is the initial and essential step, setting the stage for subsequent healing processes, including inflammation and the formation of callus.