IJAR.2017.345

Type of Article:  Original Research

Volume 5; Issue 3.3 (September 2017)

Page No.: 4383-4387

DOI: https://dx.doi.org/10.16965/ijar.2017.345

PONTICULUS POSTICUS: ITS INCIDENCE AND IMPLICATIONS FOR SCREW INSERTION INTO LATERAL MASS OF ATLAS: USING PLAIN CERVICAL RADIOGRAPH

Hiroli WF *1, Kasegaonkar MS 2, Gosavi AG 3.

*1 Assistant professor, Department of Anatomy, Ashwini Rural Medical College and Research Centre, Solapur, Maharashtra, India.

2 Assistant professor, Department of Anatomy, Ashwini Rural Medical College and Research Centre, Solapur, Maharashtra, India.

3 Professor and HOD,Department of Anatomy, Ashwini Rural Medical College and Research Centre, Solapur, Maharashtra, India.

Address for Correspondence: Dr. Hiroli WF, Assistant professor, Department of Anatomy, Ashwini Rural Medical College and Research Centre, Solapur, Maharashtra, India. E-Mail: wasim.hiroli@gmail.com

ABSTRACT

Introduction: Ponticulus posticus a bony ridge arising from the superior articular process of the atlas that completely or partially encircles the vertebral artery. We retrospectively reviewed cervical plain radiograph which had been ordered by neurosuregeon and orthopaedic surgeon for evaluation of cervical spine problems, to investigate the prevalence of ponticulus posticus in Solapur population.

Materials and Methods: 960 lateral cervical spine radiographs were obtained from radiology department, ARMCH, Kumbhari and Ashwini Sahkari Rugnalaya, Solapur. The patient of which 504 (58.33%) were males and 456(41.67%) were females. Cases were classified into incomplete and complete bony ridge.

Results: Overall incidence of Ponticulus posticus was 14.3%, with complete lesions in 6.8% and incomplete lesion in 8.02%. We found increasing percentages of patients with Ponticulus posticus from the youngest to the adolescent age group, with significantly greater prevalence in patients aged 15-30 years compared with the younger groups. Lesions were more common in males (69.7%) compared with females (30.3%), but no statistically significant difference between genders was detected for complete as well as incomplete ponticulus posticus (χ2=0.003, p=0.95).

Conclusion: The ponticulus posticus is a relatively common anomaly therefore proper identification of this anomaly on preoperative lateral radiograph should alerts surgeon to avoid using ponticulus posticus as a starting point for C1 lateral mass screw for atlantoaxial instability. If ponticulus posticus suspected or confirmed on radiograph, 3D CT scanning should be considered for variations in size and shape of ponticulus posticus and possibility of injury to vertebral artery.

Key words: Ponticulus Posticus, Atlas, Atlantoaxial instability, Lateral cervical radiograph, Lateral mass screw.

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Cite this article: Hiroli WF, Kasegaonkar MS, Gosavi AG. PONTICULUS POSTICUS: ITS INCIDENCE AND IMPLICATIONS FOR SCREW INSERTION INTO LATERAL MASS OF ATLAS: USING PLAIN CERVICAL RADIOGRAPH. Int J Anat Res 2017;5(3.3):4383-4387. DOI: 10.16965/ijar.2017.345