Table 6

Measurements (mean ± SD) at the L5 level, including comparisons of sex, ethnicity, and age.

DemographicVBAH (mm)VBPH (mm)VBSL (mm)VBIL (mm)VBPL (mm)SA (°)
 Total 30.3 ± 1.9 26.3 ± 1.9 35.7 ± 3.5 35.3 ± 3.6 33.5 ± 3.1 3.6 ± 3.6
Sex
 Female 29.6 ± 1.8 25.5 ± 1.6 33.3 ± 2.6 32.8 ± 3.0 31.4 ± 2.6 5.1 ± 3.6
 Male 30.7 ± 1.9 26.8 ± 1.9 37.1 ± 3.2 36.7 ± 3.1 34.6 ± 2.8 2.6 ± 3.2
 P  <0.001  <0.001  <0.001  <0.001  <0.001  0.013
Ethnicity
 Māori 30.1 ± 2.0 26.1 ± 1.7 36.4 ± 3.4 35.9 ± 3.6 33.8 ± 3.1 8.9 ± 3.2
 European 30.4 ± 1.8 26.4 ± 2.0 35.3 ± 3.5 35.0 ± 3.6 33.2 ± 3.1 9.2 ± 3.5
 P  0.343 0.293 <0.001  0.003  0.019  0.511
Age
 Beta (mm/y) -0.003 0.001 0.084 0.071 0.061 0.002
 P  0.620 0.922 <0.001  <0.001  <0.001  0.890
 PH (mm)  PW (mm)  VCL (mm)  VCW (mm)  Canal:body ratio
 Total 12.9 ± 1.9 16.1 ± 2.3 15.6 ± 2.1 28.2 ± 3.1 0.48 ± 0.08
Sex
 Female 12.5 ± 1.0 15.1 ± 1.8 15.1 ± 1.9 27.6 ± 2.9 0.50 ± 0.09
 Male 13.1 ± 1.4 16.6 ± 2.3 15.9 ± 2.2 28.5 ± 3.2 0.47 ± 0.08
 P  <0.001  <0.001  0.010  0.033  0.009
Ethnicity
 Māori 13.3 ± 1.2 16.5 ± 2.3 15.1 ± 1.8 28.1 ± 3.1 0.47 ± 0.08
 European 12.7 ± 1.3 15.8 ± 2.2 15.9 ± 2.3 28.2 ± 3.1 0.49 ± 0.09
 P  <0.001  0.013  0.018  0.997 0.028
Age
 Beta (mm/y) 0.011 0.033 0.006 0.033 –0.001
 P  0.013  <0.001  0.471 0.004  0.027

  • Note: Canal:body ratio, ratio of canal length to vertebral body length at the pediculolaminar level.

  • PH, pedicle height; PW, pedicle width; SA, segmental angle; VBAH, vertebral body (VB) anterior height; VBIL, VB inferior length; VBPH, VB posterior height; VBSL, VB superior length; VCL, vertebral canal length; VCW, vertebral canal width.