Introduction. Groove for the vertebral artery and the suboccipital nerve, is
located on the superior surface of the posterior arch of the first cervical
vertebra (the atlas). Presence of bony variations may transform the groove
into incomplete/complete canal, causing compression of its structures and
consequently symptoms of vertebro-basilar insufficiency. The aim of the
present study was to determine the incidence and extent of morphological
variations of the posterior arch of the atlas vertebra. Material and
Methods. The investigation was conducted on 41 atlas vertebrae, part of the
Osteological Collection of the Department of Anatomy of the Faculty of
Medicine in Novi Sad and the Faculty of Medicine in Nis. According to the
shape of the posterior arch, the atlas vertebrae were classified into three
classes. The measurements of maximum width and height diameters of the
incomplete/complete canal for the vertebral artery were performed. All the
measurements were done using open source software for image analysis, Image
J. Results. The results of the study showed that in our sample of atlases
the most common class was class I (78.05%), and class III the least frequent
(7.32%). There was no statistically significant difference in the observed
measurements of the atlas anatomical variations between the right and left
side. Conclusion. Morphometric analysis of the superior surface of the
posterior arch of the atlas vertebra has shown the existence of variations
and their importance has been discussed.
Anatomical Variations of the Scapula in Adult Egyptian Population and their Clinical Implication: Morphological and Morphometric Study on Dry Bone and Radiograph
