Investigation of the effects of odontoid bone anatomical location and structure on cervical lordosis angle in cervical ct examinations: A clinical study

Aim: In literature, anatomical variations of the odontoid process in the sagittal plane have been suggested to influence the magnitude of cervical lordosis. This study investigated the effects of odontoid process morphology on the degree of cervical lordosis. Material and Methods: This retrospective study included individuals who underwent cervical computed tomography (CT) scans and had no cervical vertebral disease. The age and gender of these individuals were recorded. Their CT images were analyzed for the morphologic relationships and morphologic measurements of the C2 vertebra and other cervical vertebrae in relation to their adjacent formations.Results: Thirty-five subjects (male=23, female=12) were included in the study. Correlation analysis revealed a positive correlation between C2-C7 Cobb angle and age, sagittal odontoid height, and sagittal C2 vertebral height values. In addition, positive correlations were found between sagittal C2-C7 height values and sagittal odontoid mid-thickness, sagittal odontoid base thickness, and C2 vertebral height values. Linear Regression analysis revealed that the T1 slope angle, sagittal C2 vertebral height, and sagittal C2-C7 height values could predict the C2-C7 Cobb angle. Conclusion: These findings suggest that cervical lordosis may decrease over time when the T1 slope angle, sagittal odontoid height, sagittal C2 vertebral height, and sagittal C2-C7 height are measured low, and thus, those individuals may be more exposed to cervical vertebral alignment disorders.