Determination of the prevalence of complete type retrotransverse and arcuate foramen of the atlas using three-dimensional computed tomography images

Purpose To determine the prevalence of complete type retrotransverse (RTF) and arcuate foramen (AF)'s in a large cohort using three-dimensional (3D) computed images (CT) and explore their correlation with each other. MethodsBetween January 2023 and August 2024, all neck and cervical vertebrae CTs taken in our hospital were scanned retrospectively. It is noted the presence or absence of complete RTF and AF, laterality, gender, and age of those included in the study. Results A total of 2000 patients were included in the study, with an equal distribution of females and males. The prevalence of complete AF was 6.4%, 10%, and 16.3% bilaterally, unilaterally, and in total. The prevalence of complete AF was 12% in females and 20.6% in males. The gender prevalence differences of bilateral AF were statistically significant (p < 0.001). The prevalence of complete RTF was 1.8%, 8.9%, and 10.6% bilaterally, unilaterally, and in total. The prevalence of complete RTF was 9.7% in females, and 11.6% in males. The prevalence differences between genders were insignificant (p = 0.173). The ipsilateral prevalence of complete AF and RTF was 0.2%, 0.2%, and 0.4%, respectively, bilateral, unilateral right, and unilateral left. Conclusions The complete AF and RTF prevalences in the study group were not uncommon. The prevalence of complete AF and RTF together is quite rare. Complete RTF is more common in elderly patients and on the left side, while complete AF does not show any difference in laterality and age, and is more common in males than in females.