Final answer:
A comminuted fracture is when the bone is shattered into three or more pieces. This complex fracture type often requires extensive treatment including closed or open reduction, following a specific healing process involving hematoma formation and callus development.
Step-by-step explanation:
A fracture where the bone is broken into three or more pieces is known as a comminuted fracture. This type of fracture is considerably complex because it involves several breaks resulting in many small fragments between two large segments. They often occur due to high-impact trauma and can be more difficult to treat due to the splintering of the bone.
Treatment of a comminuted fracture may involve closed reduction or open reduction, and healing begins with a hematoma, followed by the formation of internal and external calli as osteoblasts create new bone to replace the cartilage. This complex physiological process eventually leads to the union and remodeling of the bone.