Relations among mechanical properties, collagen fibers, and calcification in adult human cortical bone

Abstract

The relations of ultimate tensile stress and strain and modulus of elasticity to collagen fiber orientation and degree of calcification were studied in thirty-six standardized specimens of unembalmed cortical bone from adult human tibias. Highly significant positive correlations were found between tensile stress and strain and percentage of dark osteons in the break area. A similar correlation occurred between tensile strain and dark osteons plus fragments. Tensile stress and strain had highly significant negative correlations with light osteons and their fragments but a lower negative correlation with intermediate osteons. Significant negative correlations were found between the intermediate radiolucent and the marked radiolucent osteons and tensile stress and strain, respectively. Partialing out interstitial lamellae and intermediate radiolucent areas revealed significant positive and negative correlations between tensile stress and dark and light osteons, respectively. No significant correlations occurred between modulus of elasticity and any of the histological variables.