BMD-based assessment of local porosity in human femoral cortical bone

Gianluca Iori, Frans Heyer, Vantte Kilappa, Caroline Wyers, Peter Varga, Johannes Schneider, Melanie Graesel, Robert Wendlandt, Reinhard Barkmann, J. P. van den Bergh, Kay Raum*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

11 Citations (Web of Science)
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Abstract

Cortical pores are determinants of the elastic properties and of the ultimate strength of bone tissue. An increase of the overall cortical porosity (Ct.Po) as well as the local coalescence of large pores cause an impairment of the mechanical competence of bone Therefore, Ct Po represents a relevant target for identifying patients with high fracture risk. However, given their small size, the in vivo imaging of cortical pores remains challenging. The advent of modern high-resolution peripheral quantitative computed tomography (HR-pQCT) triggered new methods for the clinical assessment of Ct Po at the peripheral skeleton, either by pore segmentation or by exploiting local bone mineral density (BMD) In this work, we compared BMD-based Ct.Po estimates with highresolution reference values measured by scanning acoustic microscopy. A calibration rule to estimate local Ct.Po from BMD as assessed by HR-pQCT was derived experimentally. Within areas of interest smaller than 0.5 mm(2), our model was able to estimate the local Ct.Po with an error of 3.4%. The incorporation of the BMD mhomogeneity and of one parameter from the BMD distribution of the entire scan volume led to a relative reduction of the estimate error of 30%, if compared to an estimate based on the average BMD. When applied to the assessment of Ct.Po within entire cortical bone cross-sections, the proposed BMD-based method had better accuracy than measurements performed with a conventional threshold-based approach.

Original languageEnglish
Pages (from-to)50-61
Number of pages12
JournalBone
Volume114
DOIs
Publication statusPublished - Sep 2018

Keywords

  • Cortical bone
  • Scanning acoustic microscopy
  • HR-pQCT
  • Porosity
  • Image registration
  • SCANNING ACOUSTIC MICROSCOPY
  • HIGH-RESOLUTION
  • DISTAL RADIUS
  • MINERAL DENSITY
  • QUANTITATIVE ULTRASOUND
  • COMPUTED-TOMOGRAPHY
  • COMPACT-BONE
  • HUMAN FEMUR
  • IN-VITRO
  • ELASTICITY

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