Impact of the Shape of the Skull Base on Morphometric Parameters of the First and Second Cervical Vertebrae in 8–12-Year-Old Children: Assessment of the Condition Under Norm and Recurrent Subluxation in the C1–C2 System

Abstract

The aim of the study is to determine the impact of the shape of the skull base on the morphometric parameters of the first (C1) and second (C2) cervical vertebrae in children aged 8–12 under normal conditions and under recurrent subluxation of C1–C2. Materials and methods. The authors analysed computed tomography (CT) scans of 212 children aged 8–12 without pathology of the cervical spine and 65 patients of the same age group with recurrent subluxations of the C1-C2 vertebrae. Computed tomography was performed on a computer tomography GE OPTIMA CT 660, 64-slice machine (Russia). CT morphometry was carried out using the Radiant program (Russia). The width and length of the skull base, parameters of the first (C1) and second (C2) cervical vertebrae, and interosseous parameters were determined, the basilar index was calculated; three groups of individuals with dolicho-, meso-, or brachybasilar shape of the skull base were formed based on the value of the basilar index. One-way analysis of variance was carried out. Results The impact of the shape of the skull base of moderate strength on the transverse dimensions of the upper articular surfaces of C1 on the right and left in children without pathology of the cervical spine was revealed. Among the examined individuals with recurrent subluxation in the C1–C2 system, there was a strong connection between the shape of the skull base and the longitudinal dimensions of the upper articular surfaces of the atlas. A moderately close relationship was revealed between the shape of the skull base and the height of the body of the second cervical vertebra and with the angle of inclination of the C2 tooth in the sagittal plane in those examined without pathology of the cervical spine. In children with recurrent subluxation, a strong relationship of the controlled factor was determined with the height of the C2 body and the angle of inclination of its tooth in the sagittal plane, and a mediumstrong relationship with the sagittal diameter of the tooth. The influence of the shape of the skull base of moderate strength on the size of the anterior atlantoaxial joint space was revealed both in children without pathology of the cervical spine and in children with recurrent subluxation. In case of right-sided subluxation, a mediumstrong relationship between the shape of the skull base and the lateral distance between the base of the tooth and the medial surface of the lateral mass of C1 on the side contralateral to the subluxation was revealed. Conclusion. The shape of the skull base affects a number of anatomical structures of the first two cervical vertebrae in children aged 8–12.