Correlations between orthogonal mechanical properties and density of trabecular bone: Use of different densitometric measures

Abstract

To compare the numerous modulus-density and strength-density relations that have been found for human trabecular bone from the proximal tibia, correlations between various measures of density were sought. Hydrated and dry apparent density, ash density, and density from quantitative computed tomography (QCT) were determined for cubic trabecular specimens taken from the proximal portion of human tibiae, and correlations between these measures were found (r > 0.99, P < .001). Orthogonal moduli and strengths of the specimens were measured mechanically, and were significantly correlated with ash density according to power relations (r > or = 0.85, P < .001). The strong correlation between density from QCT and ash density indicates that these measures can be used with nearly equal precision in estimating modulus and strength of tibial trabecular bone. Equations between mechanical properties and density reported in previous studies were converted to use a common density measure and, after considering the effects of specimen size, were in general agreement with results of the present study.

Effect of force direction on femoral fracture load for two types of loading conditions

“…Briefly, the CT scan data were calibrated in terms of K2HP04 equivalent density, and apparent ash density was estimated from these data [14]. Elastic modulus and strength of each element were then computed from ash density using reported correlations for trabecular bone [9] and cortical bone [8]. Poisson's ratio of 0.4 was assumed [20,26].…”

“…Isotropic mechanical properties were assumed, but bone is anisotropic [9,20,36]. Therefore, this methodology inherently assumed that, compared with bone geometry and heterogeneity, anisotropy has a small effect on the relationships between force direction and fracture load.…”

Minimization of dental implant diameter and length according to bone quality determined by finite element analysis and optimized calculation

“…Therefore, we assumed that the bone was class D3 in this study and determined that the Young's modulus of the trabecular bone ranged from 0.1 GPa to 1.5 GPa, which corresponds to from 344 to 850HU, [7,8] for the D3 bone.…”

Experimental validation of finite element predicted bone strain in the human metatarsal

“…For inhomogeneous material properties, the elastic modulus is typically estimated using empirical equations that relate the bone density to modulus. Such empirical densityelasticity relationships have been identified for the human femur (102,(181)(182)(183)(184)(185), tibia (102,117,(186)(187)(188), pelvis (189), and vertebrae (102,183,(190)(191)(192). The empirical equations have been found to be site-specific (102), and equations for cortical bone are different from equations for trabecular bone within the same gross anatomical location (193).…”