Regional Morphological and Mechanical Characteristics in the Human Thoracic Vertebral Trabecular Bones

인체 흉추 해면골의 영역별 형태학적 및 기계적 특성 연구

  • Lee, Tae-Woo (Department of Biomedical Engineering, Yonsei Univ.) ;
  • Woo, Dae-Gon (Department of Biomedical Engineering, Yonsei Univ.) ;
  • Ko, Chang-Young (Department of Biomedical Engineering, Yonsei Univ.) ;
  • Kim, Han-Sung (Department of Biomedical Engineering, Yonsei Univ.)
  • Published : 2010.01.01

Abstract

This study analyzed the regional morphological and mechanical characteristics of vertebrae by using micro-computed tomography (micro-CT) and micro finite element analysis (FEA). For the present study, the $12^{th}$ human thoracic vertebral bones (an 85-years female and a 48-years male) were used. These were scanned by using micro-CT. Structural parameters were evaluated from the acquired 20 image data for fifteen $4{\times}4mm^2$ regions (five regions in respective layers of superior, middle and inferior part) in the thoracic vertebral trabecular bones. $4{\times}4{\times}4mm^3$ cubic finite element models of each regions were created at $70{\mu}m$ voxel resolution to investigate effective modulus ($E^+$). The present study indicated that there were significant differences in morphological and elastic mechanical characteristics of each region. There are close relationship between effective modulus and structural model index (SMI) in the bone of the 48-years male and between effective modulus and bone volume fraction (BV/TV) in the bone of the 85-years female. In addition, the effective modulus of central regions is about 80% stiffer than that of lateral regions at transverse plane. These findings may be likely to explain the previous result that a change of loading distribution of the vertebral trabecular bones is caused by spinal curvature and nucleus pulpous degeneration of the intervertebral disc.

Keywords

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