The compressive material properties of human lumbar vertebral trabecular bone were examined and compared to in vivo and in vitro measures of bone density and to the degree of macroscopic disc degeneration. No significant differences in the material properties were found for segment level (L1-L4) or for degeneration grade (I-IV), although trabecular bone specimens from segments with slightly degenerated disks (I-II) were stronger (24%) and stiffer (16%) on the average than specimens from segments with severely degenerated discs. Significant positive logarithmic regressions were obtained, however, between the in vivo and in vitro measures of trabecular bone density and trabecular bone mechanical properties. The results indicate that in vivo mineral measurements can accurately estimate the compressive material properties of lumbar vertebral trabeculae.
Keywords:
lumbar trabeculae; biomechanics; bone mineral content; disc degeneration