Relations between torsion properties and histology of adult human compact bone

Abstract

Torsion properties and the histological composition of cross sections a: the fracture site were determined for 123 standardized specimens of compact bone from various thirds and sides of the shaft of 28 femurs from adult embalmed dissecting room cadavers. Sufficient unembalmed material was unavailable. Statistically significant differences were found between the means for torsion properties and for histological composition of specimens from various regions of the bone. Significant correlation coefficients were found between the various torsion properties of the specimens and the histological components in the break area. The implications of these correlations are that torsion shear stress, shear modulus, and energy absorbed to failure tend to be increased by the number or percentage of complete osteons in the break area. Shear modulus tends to be increased, to a lesser extent, by the percentage of interstitial lamellae in the break area. All torsion properties tend to be reduced by the percentage of spaces in the break area. Shear stress and modulus also tend to be reduced by the percentage of osteon fragments in the break area.