Abstract
AIM This study aimed to estimate the frequency of the bipartite facets associated with the atlanto-occipital joint and to determine the association between the superior articulating facet of the atlas and the occipital condyle, bilateral and unilateral facets as well as the demographic profile in a South African population.
RESEARCH METHODLOGY
Data about the shape and number of facets were collected from 109 skulls and atlases from the Pretoria Bone Collection. The data was collected in 2021, employing a cross-sectional data collection form captured through Microsoft Forms 365 and exported to Microsoft Excel 365. Statistical analyses were conducted using IBM SPSS version 27.
RESULTS The results obtained from the study revealed that the frequency of the bipartition of the superior articular facet of the atlas is 15.6%, and the bipartition of the occipital condyle is 7.34%. It was found that the incidence of bipartition of the superior articular facets is approximately double on the left compared to the right. Similar numbers occurred for the bipartition of the occipital condyle comparing left to right. Sex and age did not statistically significantly contribute to prevalence of bipartition in this population. However, ancestry statistically significantly contributed to prevalence of bipartition (p=0.019), with the European population having a much higher incidence of bipartition occurring when compared to the African population. The results also showed the statistical significance of the bipartition of the superior articular facet of the atlas and the bipartition of the occipital condyle, demonstrating that both should have the same reciprocal division.
CONCLUSION The findings of this study may be valuable for surgeons, particularly neuro/vascular/orthopaedic surgeons when doing invasive treatments around the craniocervical junction. The findings can also benefit chiropractors when assessing and treating patients.