Assessment of sexual dimorphism in all lumbar vertebrae using three-dimensional multi-slice computed tomography scan

Sex determination is a critical step in identification. Scarce studies assessed the sexual dimorphism of specific lumbar vertebrae in Egyptians. This prospective study which enrolled 134 Egyptians assessed the sexual dimorphism of lumbar vertebrae using multi-slice computed tomography. At all levels, six vertebral measurements were investigated, including the upper end plate depth (EPDu), the lower end plate depth (EPDl), the upper end plate width (EPWu), the lower end plate width (EPWl), the anterior height of vertebral body (VBHa) and the posterior height of vertebral body (VBHp). The males exhibited significantly greater measurements than females, and EPDu, EPDl, EPWu, and EPWl of L1, EPDl of L2, EPWu of L3, and EPWl of L4 were the best individual sex predictors. We introduced five sex-predicting models showing exceptional area under curves ≥ 0.9. The models incorporating L1 and L2 measurements showed the highest R² of 0.791 and 0.801, respectively: Log probability of male sex=-51.524 + (5.878 x EPDu L1) + (4.383 x EPWl L1) + (4.309 x VBHp L1) and = -43.971 + (3.057 x EPDu L2) + (3.324 x EPDl L2) + (5.466 x EPWu L2) + (-10.867 x VBHa L2) + (9.699 x VBHp L2). Despite the significant correlations between the age and various measurements at different vertebral levels, lumbar vertebral bodies did not undergo uniform geometric changes with age; instead, specific regions and aspects of vertebral morphology change in distinct, sex-specific ways. We recommend validating the proposed models in different populations to generalize the obtained findings.