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Foramen arcuale: a rare morphological variation located in atlas vertebrae
Sibel Cirpan1, Goksin Nilufer Yonguc2, Mete Edizer2
1Department of Anatomy, Faculty of Medicine, Dokuz Eylül Univercity, Inciralti, 35340, Izmir, Turkey. cirpansibel@hotmail.com.
Surgical and Radiologic Anatomy : SRA
|March 17, 2017
Summary
The foramen arcuale, an anatomical variation in the atlas vertebra, was found in 15.38% of specimens. This finding is crucial for understanding potential clinical issues related to the cervical spine.
Area of Science:
- Anatomy
- Orthopedics
- Radiology
Background:
- The atlas vertebra (C1) is unique in its anatomy, forming the atlanto-occipital joint.
- The foramen arcuale is an incomplete or complete bony ring on the posterior aspect of the atlas.
- Variations in the atlas vertebra, including the foramen arcuale, can have clinical implications.
Purpose of the Study:
- To determine the incidence of the foramen arcuale in dry human atlas vertebrae.
- To investigate the morphological characteristics of the foramen arcuale and associated structures.
- To provide data that may help understand potential clinical problems caused by this anatomical variation.
Main Methods:
- Examination of 81 dry human cervical vertebrae, focusing on atlas vertebrae.
- Measurement of various parameters including diameters and areas of superior articular facets and transverse foramina.
- Assessment of the bony arch forming the roof of the foramen arcuale using calipers.
Main Results:
- Thirteen of 81 specimens (16.05%) were identified as atlas vertebrae.
- Two of these 13 atlas vertebrae (15.38%) exhibited a complete foramen arcuale.
- Statistically significant differences were noted in the antero-posterior diameter of the superior articular facets, but not in the transverse foramina diameters.
Conclusions:
- The study provides updated information on the incidence and anatomical location of the foramen arcuale in atlas vertebrae.
- The presence of the foramen arcuale may be associated with specific morphological differences in the atlas.
- Further research is warranted to fully elucidate the clinical significance of the foramen arcuale.
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