Final answer:
When a bone gap is less than 10 uM, the healing process involves stages such as the formation of a fibrocartilaginous callus and a bony callus. The calluses connect and stabilize the broken bone ends, and eventually, the bony callus is remodeled into compact bone.
Step-by-step explanation:
When a bone is fractured and the gap between the broken ends is less than 10 uM, the healing process involves several stages. Within days of the fracture, capillaries grow into the hematoma, and phagocytic cells clear away dead cells. Fibroblasts produce collagen fibers that connect the broken bone ends, while osteoblasts start to form spongy bone. The repair tissue between the broken bone ends is called the fibrocartilaginous callus, and it eventually turns into a bony callus of spongy bone. Finally, the bony callus is remodeled by osteoclasts and osteoblasts to create compact bone that resembles the original bone.