Background/Objectives: The seventh cervical vertebra (C7), the terminal segment of the cervical spine, demonstrates transitional characteristics between the cervical and thoracic regions. The transverse foramen (TF), a defining feature of all cervical vertebrae, is consistently present in C1 to C6 but shows marked variability at C7, appearing rudimentary or atypical. This study aimed to analyze the prevalence and morphology of TF of the C7 vertebra in the South African skeletal collection. The objectives of the study were to document the absence of the C7 TF, describe its morphological characteristics, and investigate associations between the C7 TF morphology and demographic factors. Methods: An exploratory osteological anatomical study appraised dry macerated C7 vertebrae. A total of six hundred and eighty-nine (n = 689) C7 vertebrae were analyzed. Frequency and descriptive statistics were used, as well as cross tabulations, to determine relationships between demographic factors and the presence or absence of a TF at C7. Results: Bilateral TF were present in 98.5% (n = 679) of vertebrae; 1.5% (n = 10) exhibited unilateral absence (4 left, 6 right). No bilateral absence was observed. The oval-oblique (toward midline) configuration was the most frequent shape bilaterally (left: 36.3%; right: 43.4%). Accessory double foramina occurred in 5.6% (left) and 8.3% (right); triple accessory foramina were rare (0.3%, right side only). Significant associations were found between TF shape and population affinity (p = 0.000, both sides) and age (p = 0.025 left, p = 0.037 right). A weak association was found between sex and right TF shape (p = 0.025). Conclusions: The findings support clinical and surgical implications for anatomical understanding of the vertebral artery, vein, and sympathetic nerve fibre pathways. The enclosed TF variation predominated, and triple accessory foramina were rare but notable.
Jones et al. (Wed,) studied this question.