Arcuate foramen: “Anatomical variation shape or adaptation legacy?”

  • Giulia Cossu
  • Louis-Marie Terrier
  • Christophe Destrieux
  • Stephane Velut
  • Patrick François
  • Ilyess Zemmoura
  • Aymeric AmelotEmail author
Original Article



The groove of the vertebral artery on the posterior arch of the atlas (sulcus arteriae vertebralis) may become a complete or partial osseous foramen: the arcuate foramen. The presence of a complete or partial arcuate foramen is a rare anatomical variant described in a minority of patients and it seems to be associated with vertigo, vertebro-basilar insufficiency, posterior circulation strokes, and musculoskeletal pain. As the number and morphology of cervical vertebrae is highly preserved, we questioned about its significance from an evolutionary point of view. We thus investigated through an extensive literature review if the arcuate foramen is a pure anatomical variation shape or if it might represent an adaptation legacy.


We observed five atlas of an extinct species, the Late Pleistocene Mammoths (M. primigenius), and we compared them with five atlas of a closely related existent species, the African elephant (L. africana).


All the mammoths’ atlas had an arcuate foramen through which the vertebral artery passed before turning anteriorly and becoming intradural. This foramen was not present in elephants’ atlas, where only a groove was observed, such as in the majority of patients.


We would like to raise the hypothesis that this peculiar morphology of mammoths’ atlas might have contributed, in association with other factors, to their precocious extinction and that the arcuate foramen might represent a disadvantage in the evolutionary process, with a low prevalence in humans being the result of a natural selection.


Atlas Arcuate foramen Mammoth Elephant Extinction Evolution Cervical vertebra Vertebral artery Groove 


Author contributions

GC, AA, and LMT design and conceptualization of the study, GC, AA, LMT, IZ, and PF analysis of the data, GC, AA, IZ, PF, SV, and CD interpretation of the data, GC, AA, LMT, IZ, PF, SV, and CD drafting of the manuscript, AA and GC writing of the manuscript, and GC, AA, LMT, IZ, PF, SV, and CD revision of the manuscript for intellectual content. AA and GC are responsible for the overall content as guarantor.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no personal conflicts of interest and no institutional financial interest in any drugs, materials, or devices described in this manuscript. The authors have no financial disclosures to report. In addition, all patients gave their informed consent for any medical and scientific investigations. This paper has not been published previously, is not under consideration for publication elsewhere. All authors are responsible for reported research.


  1. 1.
    Adisen MZ, Misirlioglu M (2017) Prevalence of ponticulus posticus among patients with different dental malocclusions by digital lateral cephalogram: a comparative study. Surg Radiol Anat 39:293–297. CrossRefGoogle Scholar
  2. 2.
    Ahn J, Duran M, Syldort S, Rizvi A, D’Antoni AV, Johal J, Iwanaga J, Oskouian RJ, Tubbs RS (2018) Arcuate foramen: anatomy, embryology, nomenclature, pathology, and surgical considerations. World Neurosurg 118:197–202. CrossRefGoogle Scholar
  3. 3.
    Allen W (1879) The varieties of the atlas in the human subject, and the homologies of its transverse processes. J Anat Physiol 14:18–27Google Scholar
  4. 4.
    Bayrakdar IS, Miloglu O, Altun O, Gumussoy I, Durna D, Yilmaz AB (2014) Cone beam computed tomography imaging of ponticulus posticus: prevalence, characteristics, and a review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol 118:e210–e219. CrossRefGoogle Scholar
  5. 5.
    Bayrakdar IS, Miloglu O, Yesiltepe S, Yilmaz AB (2017) Ponticulus posticus in a cohort of orthodontic children and adolescent patients with different sagittal skeletal anomalies: a comparative cone beam CT investigation. Folia Morphol. Google Scholar
  6. 6.
    Bayrakdar IS, Yasa Y, Duman SB, Karaturgut UE, Ocak A, Gunen Yilmaz S (2017) Cone beam computed tomography evaluation of ponticulus posticus in patients with cleft lip and palate: a retrospective radio-anatomic study. Folia Morphol. Google Scholar
  7. 7.
    Cakmak O, Gurdal E, Ekinci G, Yildiz E, Cavdar S (2005) Arcuate foramen and its clinical significance. Saudi Med J 26:1409–1413Google Scholar
  8. 8.
    Cawthon Lang K (2005) Primate factsheets: rhesus macaque (Macaca mulatta) Taxonomy, Morphology, & Ecology.
  9. 9.
    Cirpan S, Yonguc GN, Edizer M, Mas NG, Magden AO (2017) Foramen arcuale: a rare morphological variation located in atlas vertebrae. Surg Radiol Anat 39:877–884. CrossRefGoogle Scholar
  10. 10.
    Cushing KE, Ramesh V, Gardner-Medwin D, Todd NV, Gholkar A, Baxter P, Griffiths PD (2001) Tethering of the vertebral artery in the congenital arcuate foramen of the atlas vertebra: a possible cause of vertebral artery dissection in children. Dev Med Child Neurol 43:491–496CrossRefGoogle Scholar
  11. 11.
    De Kok-Mercado F, Habib M, Phelps T, Gregg L, Gailloud P (2013) Adaptions of the owl’s cervical & cephalic arteries in relation to extreme neck rotation. Science 339:514–515CrossRefGoogle Scholar
  12. 12.
    Elgafy H, Pompo F, Vela R, Elsamaloty HM (2014) Ipsilateral arcuate foramen and high-riding vertebral artery: implication on C1–C2 instrumentation. Spine J 14:1351–1355. CrossRefGoogle Scholar
  13. 13.
    Elliott RE, Tanweer O (2014) The prevalence of the ponticulus posticus (arcuate foramen) and its importance in the Goel-Harms procedure: meta-analysis and review of the literature. World Neurosurg 82:e335–e343. CrossRefGoogle Scholar
  14. 14.
    Friedrich RE (2014) Ponticulus posticus is a frequent radiographic finding on lateral cephalograms in nevoid basal cell carcinoma syndrome (Gorlin–Goltz syndrome). Anticancer Res 34:7395–7399Google Scholar
  15. 15.
    Frisoni GB, Anzola GP (1991) Vertebrobasilar ischemia after neck motion. Stroke 22:1452–1460CrossRefGoogle Scholar
  16. 16.
    Gibelli D, Cappella A, Cerutti E, Spagnoli L, Dolci C, Sforza C (2016) Prevalence of ponticulus posticus in a Northern Italian orthodontic population: a lateral cephalometric study. Surg Radiol Anat 38:309–312. CrossRefGoogle Scholar
  17. 17.
    Gupta SC, Gupta CD, Arora AK, Maheshwari BB (1979) The retrotransverse groove (canal) in the Indian atlas vertebrae. Anat Anz 145:514–516Google Scholar
  18. 18.
    Koutsouraki E, Avdelidi E, Michmizos D, Kapsali SE, Costa V, Baloyannis S (2010) Kimmerle’s anomaly as a possible causative factor of chronic tension-type headaches and neurosensory hearing loss: case report and literature review. Int J Neurosci 120:236–239. CrossRefGoogle Scholar
  19. 19.
    Krishnamurthy A, Nayak SR, Khan S, Prabhu LV, Ramanathan LA, Ganesh Kumar C, Prasad Sinha A (2007) Arcuate foramen of atlas: incidence, phylogenetic and clinical significance. Rom J Morphol Embryol 48:263–266Google Scholar
  20. 20.
    Le Minor JM, Trost O (2004) Bony ponticles of the atlas (C1) over the groove for the vertebral artery in humans and primates: polymorphism and evolutionary trends. Am J Phys Anthropol 125:16–29. CrossRefGoogle Scholar
  21. 21.
    Leonardi R, Santarelli A, Barbato E, Ciavarella D, Bolouri S, Harle F, Palazzo G, Lo Muzio L (2010) Atlanto-occipital ligament calcification: a novel sign in nevoid basal cell carcinoma syndrome. Anticancer Res 30:4265–4267Google Scholar
  22. 22.
    Limousin CA (1980) Foramen arcuale and syndrome of Barre-Lieou. Its surgical treatment. Int Orthop 4:19–23CrossRefGoogle Scholar
  23. 23.
    Miller W, Drautz DI, Ratan A, Pusey B, Qi J, Lesk AM, Tomsho LP, Packard MD, Zhao F, Sher A, Tikhonov A, Raney B, Patterson N, Lindblad-Toh K, Lander ES, Knight JR, Irzyk GP, Fredrikson KM, Harkins TT, Sheridan S, Pringle T, Schuster SC (2008) Sequencing the nuclear genome of the extinct woolly mammoth. Nature 456:387–390. CrossRefGoogle Scholar
  24. 24.
    Nystrom V, Humphrey J, Skoglund P, McKeown NJ, Vartanyan S, Shaw PW, Liden K, Jakobsson M, Barnes I, Angerbjorn A, Lister A, Dalen L (2012) Microsatellite genotyping reveals end-Pleistocene decline in mammoth autosomal genetic variation. Mol Ecol 21:3391–3402. CrossRefGoogle Scholar
  25. 25.
    Offiah CE, Day E (2017) The craniocervical junction: embryology, anatomy, biomechanics and imaging in blunt trauma. Insights Imaging 8:29–47. CrossRefGoogle Scholar
  26. 26.
    Ouyang ZY, Qiu MJ, Zhao Z, Wu XB, Tong LS (2017) Congenital anomaly of the posterior arch of the atlas: a rare risk factor for posterior circulation stroke. J Neurointerv Surg 9:e27. CrossRefGoogle Scholar
  27. 27.
    Pekala PA, Henry BM, Pekala JR, Hsieh WC, Vikse J, Sanna B, Walocha JA, Tubbs RS, Tomaszewski KA (2017) Prevalence of foramen arcuale and its clinical significance: a meta-analysis of 55,985 subjects. J Neurosurg Spine 27(3):276–290CrossRefGoogle Scholar
  28. 28.
    Prescher A (1997) The craniocervical junction in man, the osseous variations, their significance and differential diagnosis. Anat Anz 179:1–19. CrossRefGoogle Scholar
  29. 29.
    Provenzale JM, Morgenlander JC, Gress D (1996) Spontaneous vertebral dissection: clinical, conventional angiographic, CT, and MR findings. J Comput Assist Tomogr 20:185–193CrossRefGoogle Scholar
  30. 30.
    Raikkonen J, Vucetich JA, Vucetich LM, Peterson RO, Nelson MP (2013) What the inbred Scandinavian wolf population tells us about the nature of conservation. PLoS One 8:e67218. CrossRefGoogle Scholar
  31. 31.
    Saleh A, Gruber J, Bakhsh W, Rubery PT, Mesfin A (2017) How common is the Ponticulus Posticus? A CT based analysis of 2,917 patients. Spine. Google Scholar
  32. 32.
    Sanchis-Gimeno JA, Blanco-Perez E, Perez-Bermejo M, Llido S, Nalla S (2017) Retrotransverse foramen of the atlas: prevalence and bony variations. Eur Spine J. Google Scholar
  33. 33.
    Sanchis-Gimeno JA, Llido S, Miquel-Feutch M, Quiles-Guinau L, Rios L, Murillo-Llorente M, Perez-Bermejo M, Nalla S (2018) The decreasing prevalence of the arcuate foramen. World Neurosurg 110:521–525. CrossRefGoogle Scholar
  34. 34.
    Simsek S, Yigitkanli K, Comert A, Acar HI, Seckin H, Er U, Belen D, Tekdemir I, Elhan A (2008) Posterior osseous bridging of C1. J Clin Neurosci 15:686–688. CrossRefGoogle Scholar
  35. 35.
    Sivaraju L, Mani S, Prabhu K, Daniel RT, Chacko AG (2017) Three-dimensional computed tomography angiographic study of the vertebral artery in patients with congenital craniovertebral junction anomalies. Eur Spine J 26:1028–1038. CrossRefGoogle Scholar
  36. 36.
    Stubbs DM (1992) The arcuate foramen. Variability in distribution related to race and sex. Spine 17:1502–1504CrossRefGoogle Scholar
  37. 37.
    Takahata Y, Suzuki S, Agetsuma A, Okayasu N, Sugiura H, Takahashi H, Yamagiwa J, Izawa K, Furuichi T, Hill D, Maruhashi T, Saito C, Sato S, Sprague D (1998) Reproduction of wild japanese macaque females of Yakushima and Kinkazan Islands: a preliminary report. Primates 39:339–349CrossRefGoogle Scholar
  38. 38.
    Taylor WB III, Vandergriff CL, Opatowsky MJ, Layton KF (2012) Bowhunter’s syndrome diagnosed with provocative digital subtraction cerebral angiography. Proc (Bayl Univ Med Cent) 25:26–27CrossRefGoogle Scholar
  39. 39.
    Travan L, Saccheri P, Gregoraci G, Mardegan C, Crivellato E (2015) Normal anatomy and anatomic variants of vascular foramens in the cervical vertebrae: a paleo-osteological study and review of the literature. Anat Sci Int 90:308–323. CrossRefGoogle Scholar
  40. 40.
    Travan L, Saccheri P, Sabbadini G, Crivellato E (2011) Bilateral arcuate foramen associated with partial defect of the posterior arch of the atlas in a medieval skeleton: case report and review of the literature. Looking backward to go forward. Surg Radiol Anat 33:495–500. CrossRefGoogle Scholar
  41. 41.
    Tubbs RS, Johnson PC, Shoja MM, Loukas M, Oakes WJ (2007) Foramen arcuale: anatomical study and review of the literature. J Neurosurg Spine 6:31–34. CrossRefGoogle Scholar
  42. 42.
    Varela-Lasheras I, Bakker AJ, van der Mije SD, Metz JA, van Alphen J, Galis F (2011) Breaking evolutionary and pleiotropic constraints in mammals: on sloths, manatees and homeotic mutations. EvoDevo 2:11. CrossRefGoogle Scholar
  43. 43.
    Wysocki J, Bubrowski M, Reymond J, Kwiatkowski J (2003) Anatomical variants of the cervical vertebrae and the first thoracic vertebra in man. Folia Morphol 62:357–363Google Scholar
  44. 44.
    Yamamoto A, Kunimatsu Y (2006) Ontogenetic change and geographical variation of atlas bridging in Japanese macaques (Macaca fuscata). Anthropol Sci 114:153–160CrossRefGoogle Scholar
  45. 45.
    Young JP, Young PH, Ackermann MJ, Anderson PA, Riew KD (2005) The ponticulus posticus: implications for screw insertion into the first cervical lateral mass. J Bone Joint Surg Am 87:2495–2498. CrossRefGoogle Scholar

Copyright information

© Springer-Verlag France SAS, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of NeurosurgeryBretonneau University HospitalToursFrance
  2. 2.Department of NeurosurgeryLausanne University HospitalLausanneSwitzerland
  3. 3.Department of NeurosurgeryLa Pitié-Salpétrière University HospitalParisFrance

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