A histological study of remodeling at the periosteal, haversian canal, cortical endosteal, and trabecular endosteal surfaces in human rib

In human ribs the per cents of four kinds of bone surfaces (i.e., periosteal, haversian canal, cortical‐endosteal, and trabecular‐endosteal) that showed histological evidence of remodeling were measured. At each surface, (1) formative, (2) resorptive, and (3) neither form of remodeling activity was measured. The measurements were done at 350 X with the light microscope and a Zeiss integrating eyepiece II, on mineralized cross sections. The study showed that trabecular‐endosteal and cortical‐endosteal surfaces are approximately equivalent with respect to amount and type of remodeling activity per unit area at any given age. The periosteal surface showed little, and the haversian canal surface considerable, age dependent changes in amount of remodeling. Considerable variability existed within the age groups studied. An overall 16.8% of all surfaces showed histological evidence of bone formation, and 16.9% of bone resorption.