Format

Send to

Choose Destination
See comment in PubMed Commons below
Bone. 2007 Jul;41(1):129-37. Epub 2007 Mar 12.

Load distribution and the predictive power of morphological indices in the distal radius and tibia by high resolution peripheral quantitative computed tomography.

Author information

1
Department of Mechanical and Manufacturing Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive, N.W., Calgary, Alberta, Canada T2N 1N4.

Abstract

A 3D high resolution peripheral quantitative computed tomography scanner (HR-pQCT) (XtremeCT, Scanco Medical, voxel size 82 microm) has been recently developed that can perform in vivo human measurements on peripheral sites, including the wrist and tibia. The goals of this study were to use HR-pQCT measurements to determine the ability of morphological and density measurements to predict bone apparent stiffness and apparent Young's modulus in the distal radius and tibia, to determine the relative importance of cortical and trabecular bone in carrying load in the human distal radius and tibia. Furthermore, the ability of a sub-volume of trabecular bone apparent Young's modulus to predict the Young's modulus of a whole radius and tibia section was determined. A total of 25 measurements of the radius and 12 measurements of the tibia were used for morphological and finite element analyses of sections, and sub-volume cubes of trabecular bone from the distal radius and tibia. The subjects were chosen to obtain a large variation in age ranges and bone architecture and density. By combining multiple measurements, a strong ability to predict bone apparent stiffness and apparent Young's modulus was found for morphological and density measurements in the radius and tibia (R(2)>0.80). The relative importance of the trabecular and cortical bone in carrying load was also found to vary consistently with location in the sample for both the radius and the tibia. This indicates that measurements of the cortical and trabecular bone are required for assessing fracture risk. A cubic section of trabecular bone was found to be insufficient to accurately represent the apparent bone Young's modulus of a radius or tibia section. Morphological and density measurements of the distal radius and tibia have been shown in this study to predict bone apparent Young's modulus and apparent stiffness, and may indicate when a more time consuming finite element analysis is warranted. It should be noted that these results may be an overestimation of the predictive ability of structural parameters, as the influence of bone density is removed from the finite element analyses, and the results were only influenced by bone structure. A measurement of bone apparent Young's modulus is independent of subject size (as opposed to reaction force), and may provide the ability to distinguish between two patients that have similar mean morphological and density measurements; but different overall structures, and therefore, different fracture risk.

PMID:
17442649
DOI:
10.1016/j.bone.2007.02.029
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center