title: Assessment of Regional Bone Density in Fractured Vertebrae Using Quantitative Computed Tomography.
abstract: METHODS
  Cohort study.
  
  
  OBJECTIVE
  The aim of this study is to propose and evaluate a new technique to assess bone mineral density of fractured vertebrae using quantitative computed tomography (QCT).
  
  
  BACKGROUND
  There is no available technique to estimate bone mineral density (BMD) at the fractured vertebra because of the alterations in bony structures at the fracture site.
  
  
  METHODS
  Forty patients with isolated fracture from T10 to L2 were analyzed from the vertebrae above and below the fracture level. Apparent density (AD) was measured based on the relationship between QCT images attenuation coefficients and the density of calibration objects. AD of 8 independent regions of interest (ROI) within the vertebral body and 2 ROI within the pedicles of vertebrae above and below the fractured vertebra were measured. At the level of the fractured vertebra, AD was measured at the pedicles, which are typically intact. AD of the fractured vertebral body was linearly interpolated, based on the assumption that AD at the fractured vertebra is equivalent to the average AD measured in vertebrae adjacent to the fracture. Estimated and measured AD of the pedicles at the fractured level were compared to verify our assumption of linear interpolation from adjacent vertebrae.
  
  
  RESULTS
  The difference between the measured and the interpolated density of the pedicles at the fractured vertebra was 0.006 and 0.003 g/cm3for right and left pedicle respectively. The highest mean AD located at the pedicles and the lowest mean AD was found at the anterior ROI of the vertebral body. Significant negative correlation exist between age and AD of ROI in the vertebral body.
  
  
  CONCLUSIONS
  This study suggests that the proposed technique is adequate to estimate the AD of a fractured vertebra from the density of adjacent vertebrae.
authors.affiliation: Department of Surgery, University of Montreal, Montreal, QC, Canada.; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.; Research Center, CHU Sainte-Justine, Montreal, QC, Canada.; Al Zahraa Univeristy Hospital, Al Azhar University, Cairo, Egypt.
authors.forename: Hany A G
authors.initials: HA
authors.lastname: Soliman
authors.affiliation: Department of Surgery, University of Montreal, Montreal, QC, Canada.; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.; Research Center, CHU Sainte-Justine, Montreal, QC, Canada.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Mac-Thiong
authors.affiliation: Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.
authors.forename: Annie
authors.initials: A
authors.lastname: Levasseur
authors.affiliation: Department of Surgery, University of Montreal, Montreal, QC, Canada.; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.; Research Center, CHU Sainte-Justine, Montreal, QC, Canada.
authors.forename: Stefan
authors.initials: S
authors.lastname: Parent
authors.affiliation: Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.; Mechanical Engineering Department, École de Technologie Supérieure, Montreal, QC, Canada.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Petit
keywords: Bone density; Spinal fractures; Tomodensitometry