Type of Article:  Original Research

Volume 11; Issue 1 (March 2023)

Page No.: 8583-8586

DOI: https://dx.doi.org/10.16965/ijar.2022.312

Study of Incidence of Ponticulus Posterior In Dry Human Atlas Vertebra and Its Clinical Significance

Ashish Kamdi 1, Hemlata Ambade 2, Gourav Thakre 3, Ashita Kaore *4, N.Y.Kamdi 5.

1 Associate Professor, Department of Anatomy, Shri Shankaracharya Institute of Medical Sciences, Bhilai, Chattisgarh, India.

2 Assistant Professor, Department of Anatomy, Government Medical College, Nagpur, Maharashtra, India.

3 Associate Professor, Department of Anatomy, Dr Babasaheb Ambedkar Medical College, Rohini New Delhi, India.

*4 Assistant Professor, Department of Anatomy, Government Medical College, Nagpur, Nagpur, Maharashtra, India.

5 Professor and Head, Department of Anatomy, Government Medical College, Nagpur, Nagpur, Maharashtra, India.

Corresponding Author: Dr Ashita Kaore, Assistant Professor, Department of Anatomy, Government Medical College, Nagpur, Maharashtra, India. E-mail: kaoreashita@gmail.com


Background: Atlas is the first cervical vertebra. The vertebral artery lies in the groove on posterior arch of the atlas. The vertebral artery groove may sometimes get converted into a foramen. This is commonly known as ponticulus posterior (ponticulus posticus) or arcuate foramen of the atlas. These foramina may be complete or incomplete. This can lead to compression of the vertebral artery  and produce symptoms like headache, syncope, altered consciousness etc. It can also complicate manipulations of the cervical spine by reducing the blood flow during extreme rotations of head and neck. It is also associated with vertebrobasilar artery stroke So, neurosurgeons or orthopaedic surgeons who operate in this area should have a detailed knowledge of variations of groove for the vertebral artery.

Materials and Methods: The present study was conducted on 50 dried and fully ossified adult human atlas of unknown age and sex collected from the department of Anatomy, Government Medical college, Nagpur. Each atlas vertebra was carefully observed for the presence or absence of complete or incomplete ponticuli on superior surface of posterior arch of atlas.

Results: Out of the 50 vertebra studied 7(14%) showed the presence of Ponticuli. Ponticuli were incomplete in all 7 atlas vertebras. Complete ring was not observed in any of the atlas vertebra .Out of the 7 ponticuli 6(12%) were found to be unilateral and in only 1 (2%) case it was found to be bilateral. Out of the 6 ponticuli 4(8%) were noticed on the Left side and 2(4%) were present on the right side.

Conclusion: Presence of incomplete ponticulus posterior might cause cervical pain and even cerebrovascular disorders due to pressure on third part of vertebral artery present in the vertebral artery groove. This anatomical knowledge is important for neurosurgeons, orthopaedic surgeons, radiologists and clinicians while dealing with this region.

KEYWORDS: Ponticulus Posterior, Atlas, Cervical Vertebra, Cerebrovascular disorders, Vertebral artery.


[1]. Keith L Moore. The back. Satterfield TS. Clinically Oriented Anatomy. 3rd edn: Baltimore, Willams & Wilkins. 1992; p.331.
[2]. Standring S. Gray’s Anatomy. The anatomical basis of Clinical practice. 40th ed:. London, Churchill Livingstone. 2008; p. 719-720.
[3]. Sinnatamby CS. Head and neck and spine. Crum R. Last’s Anatomy, Regional and Applied. 10th edn: Churchill Livingstone Edinburgh. London 2001; p. 419.
[4]. Romanes GJ. The blood vascular and lymphatic system. Cunningham’s Textbook of Anatomy. 10th edn: Oxford University Press. London 1964; p. 879.
[5]. Last RJ: In Anatomy Regional and applied. 11th Ed. J and A Churchill Ltd. London. 2006; pp. 443.
[6]. Tubbs RS, Johnson PC, Shoja MM, Loukas M, Oakes WJ, Foramen arcuale: Anatomical study and review of the literature. J Neurosurg Spine. 2007;6(1):31– 34.
[7]. Sylvia S, Kulkarni S, Hatti A. Bilateral Retro Articular ring in Atlas vertebra – A Case Report. Anatomica Karnataka. 2011;5(1):81-86.
[8]. Karau PB, Ogeng’o JA, Hassanali J, Odula PO. Morphometry and Variations of Bony Ponticles of the Atlas Vertebrae (C1) in Kenyans. Int J of Morphology. 2010;28(4):1019-1024.
[9]. Mitchell J. The incidence and dimensions of the retroarticular canal of the atlas vertebra. Acta Anat 1998 (a);163:113-120.
[10]. Le Minor, J. M. & Trost, O. 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.2004;125:16-29.
[11]. Lalit M, Piplani S, Arora A K, Kullar J S, Sharma T. Incidence of Atlas Bridges and Tunnels- Their Phylogeny, Ontogeny and Clinical Implications. Rev Arg De Anat Clin. 2014;6(1):26-34
[12]. .Hasan M, Shukla S, Siddiqui MS, Singh D. Posterolateral tunnels and ponticuli in human atlas vertebrae. J. Anat 2001;199:339-343.
[13]. Cakmak O, Gurdal E, Ekinci G, Yildiz E, Cavdar S. Arcuate foramen and its clinical significance. Saudi Med J. 2005;26:1409-1413.
[14]. Krishnamurthy A, Nayak SR, Khan S, Prabhu Latha V, Ramanathan LA, Kumar CG, et al. Arcuate foramen of atlas: Incidence, Phylogenetic and Clinical significance. Romanian J of Morphol and Embryol. 2007;48(3):263-266.
[15]. Dahiphale VP, Bahetee BH. The retroarticular vertebral artery ring of the atlas and its significance. J Anat Soc. India. 2009;58:149-151.
[16]. Zambare BR, Reddy BB. The retroarticular ring of the atlas and its clinical significance. Anatomica Karnatka. 2011;5(2):74-76.
[17]. Nandhini Venkatachalam.Ponticuli in Human Atlas Vertebra and its significance.International Journal of Health Sciences and Research.2015;5(6):246-250.
[18]. Patel NP, Gupta DS, Parmar ND. Incidence of ponticles in human atlas vertebrae- A study from South Gujarat population. Ind J Clin Anat Physiol. 2015;2(3):135-39.
[19]. Paraskevas G, Papaziogas B, Tsonidis C, Kapetanos G. Gross morphology of the bridges over the vertebral artery groove on the atlas. Surg Radiol Anat. 2005;27(2):129-36.
[20]. Kendrick GA, Biggs NL. Incidence of the ponticulus posticus of the first cervical vertebra between ages six to seventeen. Anatomical Record. 1963; 145:449-451
[21]. Dhall U, Chhabra S, Dhal JC. Bilateral asymmetry in bridges and superior articular facets of atlas vertebra. J Anat Soc.India. 1993;42:23-27.
[22]. Mitchell, J. The incidence of the lateral bridge of the atlas vertebra. J. Anat. 1998b; 193:283-5.
[23]. Parkin PJ, Wallis WE, Wilson JE. Vertebral artery occlusion following manipulation of the neck. N Z Med. 1978;88:441-443.
[24]. Krueger BR, Okazaki H. Vertebral basilar distribution infarction following chiropractic cervical manipulation. Mayo Clinic Proceedings. 1980;55:322- 332.
[25]. Cushing KE, Ramesh V, Gardner Medwin D, Todd NV, Gholkar A, Baxter P, Griffiths PD. 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. 2001;43(7):491–496.

Cite this article: Ashish Kamdi, Hemlata Ambade, Gourav Thakre, Ashita Kaore, N.Y.Kamdi. Study of Incidence of Ponticulus Posterior In Dry Human Atlas Vertebra and Its Clinical Significance. Int J Anat Res 2023;11(1):8583-8586. DOI: 10.16965/ijar.2022.312