Abstract
Background
The transverse foramina are openings within the transverse processes that transmit the vertebral artery, vertebral veins, and sympathetic nerves within the cervical spine. They are subject to variations, such as unclosed transverse foramina (UTF), and may be linked to vertebral pathologies. The atlas (C1) is the most susceptible cervical vertebrae to the UTF variation.
Aim
This study aimed to investigate the prevalence of UTF in the cervical spine in a South African skeletal population sample and whether there are any associations between UTF and demographic factors such as age, sex, population affinity, and ancestry.
Procedure
The research was a descriptive, and quantitative osteological study. One thousand one hundred and eighteen cervical spines were appraised and after applying the inclusion and exclusion criteria, a total sample of 800 individuals (5600 cervical vertebrae) were examined for UTF, and the results were recorded and analysed.
Results
From the 800 skeletons, a total of 17,4% (n=139/800) presented with UTF. A total of 120 individuals had 1 UTF present, 16 individuals had 2 UTF present, 2 individuals had 3 UTF present and 1 individual had 5 UTF present. From the 5600 vertebrae appraised, 2,9% demonstrated the presence of a UTF (n=163/5600) in the total sample. The prevalence for each vertebral level within the UTF cohort in the descending order was: C1 (8,6%, n=69/800), C3 (2,5%, n=20/800), C6 (2,4%, n=19/800), C7 (2,4%, n=19/800), C2 (2,1%, n=17/800), C4 (1,3%, n=10/800), and C5 (1,1%, n=9/800). The prevalence of the side showed 1,2% presented with
vi
unilateral right (n=68/5600), while 1% were unilateral left (n=56/5600), and 0,7% demonstrated bilateral presentation (n=39/5600).
The younger than 50 age group (1,7%, n=94) had a greater prevalence of UTF than the 50-year and older (1,2%, n=69). Prevalence of UTF was higher in the male than females (1,8%, n=102 vs 1,1%, n=61). Population affinities were divided into Black and White populations with the Black population containing 2,3% (n=129) while the White population presented with 0,6% (n=34) of the UTF in the sample. The Black population was subdivided into three ancestry groups, Zulu, Xhosa, and Sotho, with 0,9% (n=52) of the Sotho population demonstrating the highest prevalence of UTF, followed by Zulu and then Xhosa (0,9%, n=49; 0,5%, n=28, respectively). Statistically significant results were found for spinal levels C2 (p=0,05) and C7 (p=0,03) for younger age and the presence of UTF. However, the significance effect was low (0,07).
Conclusion
The prevalence of UTF in the South African skeletal sample was 17,4% with 2,9% of the 5600 cervical vertebrae demonstrating UTF. Individuals with UTF may be susceptible to vertebral artery insufficiency (VBAI) or injury. The information obtained from this research may help inform healthcare practitioners about the prevalence and demographic factors of UTF in a South African context.