ABSTRACT

Objective:

The aim of this study is to determine the normal diameter range of the T12 and L1 vertebrae in adults in groups of different gender and age.

Materials and Methods:

300 adult patients who had no pathology in the thoracolumbar junction were examined in this study. 150 male and 150 female patients were divided into 18–30, 31–50, and 51–70 age groups. In computed tomography images of the patients, the T12 and L1 vertebral pedicle diameters were calculated based on bilateral millimeter dimensions in axial sections. The statistical data were presented as mean and standard deviation. The Kruskal-Wallis and Mann-Whitney U tests were used for comparisons between the groups. The PASW Statistics v18 program was used for statistical analysis.

Results:

The mean pedicle diameters of the T12 and L1 vertebrae in men were calculated as 6.06 mm and 5.76 mm, respectively, in the 18–30 age group, as 6.10 mm and 6.10 mm, respectively, in the 31– 50 age group, and as 5.57 mm and 5.59 mm, respectively, in the 51–70 age group. The mean pedicle diameters of the T12 and L1 vertebrae in women were calculated as 4.83 mm and 4.77 mm, respectively, in the 18–30 age group, as 4.61 mm and 4.52 mm, respectively, in the 31–50 age group, and as 4.62 mm and 4.19 mm, respectively, in the 51–70 age group. The T12 and L1 pedicle diameters were also compared bilaterally in males and females in each age group, but there were no statistically significant differences. In terms of gender, the pedicle diameters of males were found to be greater than the pedicle diameters of females, and this was statistically significant.

Conclusion:

The range of thoracolumbar pedicle diameters of adult males was between 4 mm and 8 mm, while this ranged between 2 mm and 7 mm in females. Based on these results, patients who will receive surgery using a pedicle screw instrumentation technique must be evaluated beforehand with an anatomical and morphometric analysis of the vertebral pedicles, in order to decrease the complication rates.