Determination of young's modulus of cortical bone directly from computed tomography: A rabbit model

The determination of inhomogeneous material properties of bone in finite element analysis is currently based on two converting formulae that convert the computed tomography number into bone density and then into Young's modulus. However, there are variations between studies and no standardized set of formulae exists. The objective of the current study was to propose a procedure for the determination of Young's modulus of cortical bone directly from computed tomography using a rabbit model. Three-point bending experiments and finite element analyses were used to derive a formula for converting the computed tomography number into Young's modulus. The formula was found to be E=0.8324×(CT)^1.057, where E is the Young's modulus, and CT is the computed tomography number. The correlation coefficient between finite element analysis results based on the above formula and the experimental results was found to be 0.973. The proposed procedure was found to be feasible, and it has the advantage of saving computational time. Similar conversion formulae can be derived for human bone when cadaveric bones are available. Such formulae can simplify the procedure for determining the inhomogeneous material properties of cortical bone directly from computed tomography.