A 46-year-old woman fell on ice in winter and

broke her tibia. After an X-ray examination, it was decided to cast the limb.

After 2 weeks she presented for a check-up and tightening of the cast; after 8

weeks the cast was removed. During the healing process of the bone fracture, a

blood clot first appears filling the fracture. The clot is remodelled into a

non-specific granulation tissue. This tissue then forms a connective callus. In

the temporary connective tissue, both the fibrocartilage and hyaline cartilage

differentiate. The connective tissue and cartilage are subsequently replaced by

bone. Which type of bone tissue appears first during the healing process?