Fig. 4

Rat hindlimb stained with alizarin red S. a Cross polarization image of hindlimb bones visible through clarified soft tissue (arrows). b Fluorescent image of magnified knee joint with spongy (full arrow) or compact (empty arrow) bone and epiphyseal line (arrowhead). c Metatarsal area with visible difference in bone density of metaphysis (full arrow) and diaphysis (empty arrow). Scale bar, 1 mm