Digital image analysis of vertebral body L4 and its ossification center in the human fetus.

Using a Siemens-Biograph 128 mCT camera the morphometric analysis of the L4 vertebral body and its ossification center were done in 55human fetuses aged 17 to 30weeks. No sex differences were found. The mean height, transverse and sagittal diameters of L4 vertebral body followed the logarithmic functions: y = -11.797+ 5.208 × ln(age) ± 0.372, y = -23.462 + 9.428 × ln(age) ± 0.702, y = 2.770 + 13.521 × ln(age) ± 1.722, respectively. The mean cross-sectional area of L4 vertebral body followed the linear function: y = -30.683 + 1.976 × age ± 2.701. The mean volume of L4 vertebral body followed the second-degree polynomial function: y = -93.983+ 0.385 × (age)² ± 23.707. The mean transverse and sagittal diameters of the ossification center of L4 vertebral body followed the natural logarithmic function: y = -27.106 + 10.178 × ln(age) ± 0.769 and y = -13.345 + 5.458 × ln(age) ± 0.424, respectively. The mean cross-sectional area and the volume of the ossification center of L4 vertebral body followed the linear function: y = -30.683 + 1.976 × age ± 2.701 and y = -43.214 + 2.760 × age ± 4.085, respectively.