Abstract
The proatlas is a rare, vestigial bone formation in humans, where it forms the occipital bone and the dorsal part of the foramen magnum after fusing with the upper three occipital sclerotomes. As a result, it is not generally observed as a separate structure. However, there are instances in which proatlantal remnants have been noted in man. On occasion, additional vertebra will appear in front of the atlas, thus the term “proatlas.”
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Bordes, S.J., Tubbs, R.S. (2020). The Proatlas. In: Tubbs, R., Turgut, M., Oakes, W. (eds) The Chiari Malformations. Springer, Cham. https://doi.org/10.1007/978-3-030-44862-2_7
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DOI: https://doi.org/10.1007/978-3-030-44862-2_7
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