Evaluation of the Sacral and Coccygeal Curvatures Calculated via Computed Tomography Images Based on Gender

Abstract

Objective: The skeletal structure has a significant role in the estimation of human gender. The os sacrum and os coccyx bones that constitute the pelvic skeleton are important in sex estimation due to their functional differences based on sex. In the present study, we aimed to determine the differences in os sacral and os coccygeal curvatures calculated with orthogonal plane computed tomography images based on gender. 
 Methods: Computed tomography images of 150 healthy individuals (75 females, 75 males) between the ages of 25-50 were used in the study. The computed tomography images were edited into a suitable format by the Horos software for measurement. Six sacral and coccygeal measurements, lumbosacral angle (LSA), sacral curvature (SC), sacral kyphosis (SK), sacrococcygeal angle (SCA), sacrococcygeal joint angle (SCJA), and coccygeal curvature (CC) were conducted on the sagittal image. 
 Results: The measurement results indicated that LSA and SCA values were higher in male subjects when compared to females, and SCJA values were higher in females when compared to males (p≤0.05). Quadratic Discriminant Analysis (QDA) results indicated that these parameters were 93.3% effective in estimating male gender, 85.3% effective in estimating female gender, with an overall estimation rate of 89.3%. 
 Conclusion: According to these results, it was concluded that the lumbosacral and sacrococcygeal joints appear flatter in men than in women. SC, SK and CC parameters did not show sexual dimorphism. Considering all the parameters we used, we achieved a high rate of gender discrimination.