Aim:Ponticulus posticus (PP) and ponticulus lateralis (PL) are bony anomalies of the atlas. This study aimed to investigate the prevalence and type of PP and PL in the Chinese population by analyzing computed tomography (CT) scans, and to uncover the pathogenesis of PP and PL.Material and Methods:A total of 4,047 cases were included in this study. We evaluated cervical spine CT scans with three dimensional reconstructions and collected age, gender, and presence of PP and PL in each case. If either or both were present, location and type were recorded.Results:The overall prevalence of PP was 8.01%. The age of patients with PP was significantly higher than those without. Men had a higher prevalence of PP than women. The presence of PP was more common on the left side than the right. According to our previous classification, the most common type of a PP was AC (32.41%), followed by CC (20.06%) and CA (16.98%). The overall prevalence of PL was 4.67%, with no differences between age groups, genders or by location. The most common type of PL was AC (43.92%), followed by CA (35.98%) and CC (20.11%). The prevalence of PP and PL occurring in the same patient was 1.26%.Conclusion:Based on cervical spine CT scans of 4,047 Chinese patients, we found that the prevalence of PP and PL were 8.01% and 4.67%, respectively. PP was more common in older patients, which strongly suggests that PP may be a congenital osseous anomaly of the atlas that mineralizes during aging.