Morphometric analysis of foramen magnum in the determination of sex using computed tomography

Background: sex identification by morphological assessment of various bones of the skeleton had been one of the oldest approaches in forensic anthropology and medico-legal cases. Aim and Objective: The aim of this study was to make the morphometric measurements of the foramen magnum in determining the feasibility of sex determination using computed tomography (CT). Materials and Methods: The data for our study was obtained from 100 patients having CT scan of the head and neck region (Siemens Somatom 256 slice CT scanner) with 1mm contiguous axial scans using bone window settings (2000 HU with 400 HU in centre), scan time of one second and exposure parameters 140 kVp and 70mA. The different measurements taken include the antero-posterior (AP) diameter, transverse diameter and area of the foramen magnum. Results: There were 50 males and 50 females with the age range of 18 to 75 years. Males have a higher average value than females in all of the parameters measured on foramen magnum. By using Student's T-test, all the measured parameters showed significant difference between the sexes (p < 0.01). Conclusion: The expression of sexual dimorphism in the foramen magnum region shows significant difference between the sexes, therefore this area of the skull should be considered a useful area in the identification of sex.