Prediction of cortical bone porosityIn Vitro by microcomputed tomography

Abstract

The high importance of intracortical porosity for mechanical strength of cortical bone has been established. The contribution of other parameters of microstructure such as osteon dimensions for strength is in discussion. The aim of this study was to evaluate the predictive value of microcomputed tomography (mCT) for porosity and other microstructural parameters of cortical bone in cortical bone biopsies. Femoral cortical bone specimens from the middiaphysis of 24 patients were harvested during the procedure of total hip replacement at the location where normally one hole (Ø 4.5 mm) for the relief of the intramedullary pressure is placed. In vitro intracortical porosity and bone mineral density (BMD) measurements by mCT were compared with structural parameters assessed in histological sections of the same specimens. A strong correlation was found between intracortical porosity measured by mCT and histological porosity (r = 0.95, P <0.0001). Porosity measured by mCT was also a strong predictor for other parameters describing dimensions of porous structures. BMD?1 was associated with osteonal area (r = -0.76, P <0.0001). We consider the measurement of porosity by mCT as a very potent procedure for assessing intracortical porosity and parameters related to porous structures of cortical bone nondestructively in vitro.

Influence of vascular porosity on fluid flow and nutrient transport in loaded cortical bone

“…Although bone fluid flow is mainly a transverse phenomenon, the applicability of the simulations was limited to a small region of the diaphysis. Vascular canals were assumed to be straight shafts spanning the tibia longitudinally, while vasculature forms a three-dimensional canal complex (Bousson et al, 2004;Cooper et al, 2003;Petrtyl et al, 1996;Wachter et al, 2001). Although total vascular porosity of the model agreed with experimental measurements, the size and number of modeled canals were simplified.…”

The effect of restriction of dietary calcium on trabecular and cortical bone mineral density in the rats

“…To overcome the limitations of DEXA, new scanning techniques have been introduced. Among them, peripheral quantitative computer tomography (pQCT) is designed to reconstruct the target bone in 3D and measure volumetric bone mineral density (v-BMD) from each of cortical and trabecular bones, providing a better prediction of fracture risk [29,30]. Bilateral cortical v-BMDs were not significantly different between the two groups, either.…”

The dependence of transversely isotropic elasticity of human femoral cortical bone on porosity

“…the mechanical properties of cortical bone and porosity (Currey, 1988;Evans, 1978;McCalden et al, 1993;Schaffler and Burr, 1988;Wachter et al, 2001). Particularly, a power law relationship between elastic modulus and porosity has been proposed (Currey, 1988;Schaffler and Burr, 1988).…”