Intracortical Remodeling Parameters Are Associated With Measures of Bone Robustness

ABSTRACT
Prior work identified a novel association between bone robustness and porosity, which may be part of a broader interaction whereby the skeletal system compensates for the natural variation in robustness (bone width relative to length) by modulating tissue‐level mechanical properties to increase stiffness of slender bones and to reduce mass of robust bones. To further understand this association, we tested the hypothesis that the relationship between robustness and porosity is mediated through intracortical, BMU‐based (basic multicellular unit) remodeling. We quantified cortical porosity, mineralization, and histomorphometry at two sites (38% and 66% of the length) in human cadaveric tibiae. We found significant correlations between robustness and several histomorphometric variables (e.g., % secondary tissue [R2 = 0.68, P < 0.004], total osteon area [R2 = 0.42, P < 0.04]) at the 66% site. Although these associations were weaker at the 38% site, significant correlations between histological variables were identified between the two sites indicating that both respond to the same global effects and demonstrate a similar character at the whole bone level. Thus, robust bones tended to have larger and more numerous osteons with less infilling, resulting in bigger pores and more secondary bone area. These results suggest that local regulation of BMU‐based remodeling may be further modulated by a global signal associated with robustness, such that ...

Source: The Anatomical Record Part B: The New Anatomist - June 25, 2014 Category: Anatomy Authors: Haviva M. Goldman, Naomi A. Hampson, J. Jared Guth, David Lin, Karl J. Jepsen Tags: Full Length Article Source Type: research