During endochondral bone formation and fracture healing, cells committed to
chondrogenesis undergo a temporally restricted program of differentiation that is
characterized by sequential changes in their phenotype and gene expression. This results in
the manufacture, remodeling, and mineralization of a cartilage template on which bone is
laid down. Articular chondrocytes undergo a similar but restricted differentiation program that
does not proceed to mineralization, except in pathologic conditions such as osteoarthritis …