title: Radiographic trabecular 2D and 3D parameters of proximal femoral bone cores correlate with each other and with yield stress.
abstract: Radiographic images of bone cores taken from cadaver proximal femora provided two-dimensional parameters of projected trabecular patterns that correlated highly with conceptually equivalent three-dimensional parameters in the same cores. Measurements also highly correlated with yield stress, suggesting that both parameters have similar biomechanical qualities.
  
  
  BACKGROUND
  We compared morphometric measurements of trabecular patterns in two-dimensional (2D) projection radiographic images of cores from cadaver proximal femoral bones with conceptually equivalent measurements from three-dimensional microcomputed tomography (3D microCT) images.
  
  
  METHODS
  Seven cadaver proximal femora provided 47 excised cores from seven regions. Digitized radiographs of those cores were processed with software that extracts trabecular patterns. Measurements of their distribution, geometry, and connectivity were compared with 3D parameters of similar definition derived from microCT of those cores. The relationship between 2D and 3D measurements and yield stress was also examined.
  
  
  RESULTS
  2D measurements strongly correlated with conceptually equivalent measurements obtained using 3D microCT. In all cases, the correlation coefficients were high, ranging from r = 0.84 (p < 0.001) to r = 0.93 (p < 0.001). The correlation coefficients between 2D and 3D measurements and yield stress of the cores were also high (r = 0.60 and 0.82, p < 0.001, respectively).
  
  
  CONCLUSIONS
  These findings provide correlative and biomechanical evidence supporting the qualitative similarity of 2D microstructural parameters extracted from plain proximal femoral core X-ray images to conceptually equivalent 3D microstructural measurements of those same cores.
authors.affiliation: Imaging Therapeutics Inc., Redwood City, CA 94063, USA. daniel.steines@imatx.com
authors.forename: D
authors.initials: D
authors.lastname: Steines
authors.forename: S-W
authors.initials: SW
authors.lastname: Liew
authors.forename: C
authors.initials: C
authors.lastname: Arnaud
authors.forename: R
authors.initials: R
authors.lastname: Vargas-Voracek
authors.forename: A
authors.initials: A
authors.lastname: Nazarian
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: B
authors.initials: B
authors.lastname: Snyder
authors.forename: P
authors.initials: P
authors.lastname: Hess
authors.forename: P
authors.initials: P
authors.lastname: Lang