A morphometric and morphological analysis of the foramen magnum, hypoglossal canal and occipital condyles in a select South African population

Background: The foramen magnum is a centralised structure found at the base of the skull. This orifice is a passageway that allows secondary structures, such as the medulla oblongata and meninges, to pass through. The occipital condyles are small structures on either side of the foramen magnum, forming the craniovertebral joint. The hypoglossal canal is an orifice located on the occipital canal, providing a passageway for hypoglossal nerves. The study aimed to document the morphology and morphometry of the foramen magnum, occipital condyles and hypoglossal canals within a South African population. Materials and methods: Fifty skulls (n = 50) were randomly selected from the Department of Clinical Anatomy, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal. This study investigated the morphological and morphometric parameters of the foramen magnum, occipital condyles and hypoglossal canal. The morphometric parameters were measured using a digital Vernier calliper. The data was statistically analysed using SPSS, and a p-value of <0.05 was deemed statistically significant. Results: The mean length and width of the foramen magnum was found to be 35.19 mm and 27.77 mm, respectively. The mean index of the foramen magnum was 1.3, which indicated that the foramen magnum was predominantly oval-shaped within the selected sample. The occipital condyles have a mean length and width of 21.73 mm and 12.87 mm, respectively. Furthermore, the most prevalent shape of the occipital condyles was oval. The mean length and width of the hypoglossal canals were 5.14 mm and 3.87 mm, respectively. While the most prevalent shape of the hypoglossal canal was oval and round on the right and left sides, respectively. Conclusions: The findings of this study may assist in reducing the risk of injury and mortalities during trans-condylar approach procedures. (Folia Morphol 2024; 83, 2: 412-416)