Biometric analysis of the area of the foramen magnum using the ImageJ software, and its correlation with the Radinsky and Teixeira formulas

Introduction: The knowledge of biometrics in the area of the foramen magnum is of importance in the pathophysiology of several disorders of the craniocervical junction, as well as for anthropology, anatomy and forensic medicine. The analysis of the area using image technology is still very scarce in the literature. Objective: Determine the area of the foramen magnum using ImageJ and correlate it with the areas calculated by the formulas of Radinsky and Teixeira. Methodology: 104 human dry skulls of adults were studied, 62 male and 42 female, belonging to the anatomy laboratories of the Universities: Tiradentes (UNIT) and Federal de Sergipe (UFS). To calculate the area of the foramen magnum, the ImageJ software was used, while the measures, length and width, were performed using a digital caliper. The areas calculated by ImageJ were compared to those calculated using the Radinsky and Teixeira formula. Results: The area of the foramen magnum measured by ImageJ ranged from 532.14 to 1135.79mm², with an overall average of 758.71mm². According to Radinsky's formula, the area of the foramen magnum varied from 610.35 to 1233.09mm², with an average of 828.25mm²; and in Teixeira, the area ranged from 633.67 to 1241.29mm², with an average of 840.16mm². The Cronbach's alpha correlating the three methods was equal to 0.950. Conclusion: The calculation of the area of the foramen magnum, using the ImageJ software was significantly close to the area calculated by the formulas of Radinsky and Teixeira (Cronbach's alpha=0.950), proving to be useful for forensic practice. Sexual dismorphism can be found, varying its appearance in literature, but only in relation to its size, but not its shape. However some other authors seem to have not found any sexual dismorphism.