Summary
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.
Introduction
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 µCT) 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 µCT 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 µCT. 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.
Keywords Femur - Microarchitecture - Micro-CT - Radiograph - Yield stress
Phase 1 NIH SBIR 1 R43 AR049655