In the spine surgery, each vertebrae in the thoracolumbar region has to be notably analysed as a separate region because of their common anatomical and morphometric features. Especially being a biomechanically transition zone leads to happen most of the fractures in this region. Throughout this study, the purpose is to measure the morphometric features of each vertebrae in the thoracolumbar region in healthy population. For this purpose A-P length on the sagittal plane, vertebral body heights, A-P and lateral radius on the axial plane of T11, T12 and L1 vertebrae of 100 healthy male patients with mean age 33.4 ± 4.4 (30-40 age) who has been to outpatient clinic and CT, MRI and Xrays have been realised for other reasons, were measured and recorded. Furthermore, all correlations analysed if there is a common constant between height, length and A-P and lateral radius by setting a mathematical function.

In this study the mean A-P length for T11, T12 and L1 were 41.1±3.4 mm, 42.2±3.8 mm, 43.1±3.7 mm and the heights were 30.1±2.9 mm, 31.1±3.3 mm, 31.8±3.4 mm determined respectively. There were no statistical difference between heights and lengths of vertebrae (p>0.05). There were no statistical difference between lateral and A-P radius measured on axial plane (p>0.05). We have detected that there was a statistically similar constant in the ratio of 0,1 between height and A-P length and this constant was 1.355±0.111 and the distribution was statistically similar.

According to the results of this study and based on retrospective radiologic analysis of between 20- 40 ages 100 healthy individual, there was no statistically difference between morphometric measures of each thoracolumbar vertebrae and there was only one similar constant difference ( as a constant multiplier) between A-P length and side diameters of regional vertebrae.

Keywords: Thoracolumbar vertebrae, morphometric analysis, dimensions of vertebral body.