International Journal of Anatomy and Research

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Type of Article: Original Research

Year: 2016 | Volume 4 | Issue 3 | Page No. 2526-2530

Date of Publication: 31-07-2016



Monika Lalit *1, Sanjay Piplani 2, Poonam Verma 3.

*1 Assistant Professor, Department of Anatomy, SGRDIMS&R, Amritsar, Punjab, India.

2 Professor, Department of Pathology, SGRDIMS&R, Amritsar, Punjab, India.

3 Professor, Department of Anatomy, SGRDIMS&R, Amritsar, Punjab, India.

Address: Dr Monika Lalit, Assistant Professor, Department of Anatomy, SGRDIMS & R, Vallah, Amritsar 143001, Punjab, India.  


Background:  The third part of vertebral artery on its exit from the FT of atlas is vulnerable for compression by External factors like bony outgrowths which may be complete to form the retroarticular bony rings. Such rings may predispose to vertebrobasilar insufficiency, Barre- lieou and cervicogenic syndrome especially in neck movements. The aim of this study is to know the dimensions of Retroarticular Bony Ring as the knowledge about such dimensions can improve the success rate of surgeries.
Materials and Methods:   120 sides on sixty dry adult human atlas vertebrae were obtained in the Department of Anatomy, Government Medical College, Amritsar, Punjab, India. The Retroarticular Bony Rings (RBR) were identified following the criteria used by Mitchell J and Hasan et al. Linear dimensions of Retroarticular Bony Ring (RB Rings) like Antero-posterior (Length) Supero-inferior (Height) and Medio-lateral (Width) were measured with the help of digital vernier caliper.
Results:  The complete ponticuli were seen in 10 vertebrae (16.66%). Bilateral retroarticular bony rings have the lowest incidence of 3.33%, 5% on right side and 8.33%  on left side. The mean anteroposterior diameter of the right retroarticular canal was 8.79mm and left side was 8.47mm, superoinferior diameter was 5.98mm on right side and 5.47mm on left side and mediolateral diameter was 4.76mm on right side and 4.42mm on left side.
Conclusions:  The Knowledge about the dimensions of Bony ring of atlas is important for radiologists, otolaryngologists, neurologists and orthopaedicians as this information may be helpful in avoiding and reducing complications such as vertebral  artery injury and spinal cord injury during spine surgeries.
Key words:  Retroarticular Bony ring, Vertebral artery, Ponticuli, Bony Canal, Atlas vertebrae


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Monika Lalit, Sanjay Piplani, Poonam Verma. STUDY OF DIMENSIONS OF RETROARTICULAR BONY RINGS IN HUMAN ATLAS VERTEBRAE. Int J Anat Res 2016;4(3):2526-2530. DOI: 10.16965/ijar.2016.258




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