Figure 1.

Mesenchymal phase of fracture regeneration. Bones were harvested from mice 5 and 10 days postfracture. Callus tissue was decalcified, embedded in paraffin, sectioned, and stained with saffranin-o. Images were collected at 25× and 200× magnification to demonstrate the mesenchymal phase at day 5, and then how those cells differentiate to become bone-forming cells at day 10. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound