Type of Article:  Original Research

Volume 7; Issue 3.3 (September 2019)

Page No.: 6911-6917

DOI: https://dx.doi.org/10.16965/ijar.2019.254


Susie Jeyalyn David.

Assistant Professor, Department of Anatomy, Sree Mookambika Institute of Medical Sciences, Kulasekharam, Kanyakumari District, Tamilnadu, India.

Corresponding author: Susie Jeyalyn David, Assistant Professor, Department of Anatomy, Sree Mookambika Institute of Medical Sciences, Kulasekharam -629 161, Kanyakumari District, Tamilnadu, India. Ph: +91 9443622530. E-Mail: drsuslyn@gmail.com


Introduction: The sacral hiatus is located on the posterior aspect of the lower end of the sacrum, where the extradural space ends . The clinically significant features of the posterior surface of the sacrum are the triangular or inverted ‘U’ shape sacral hiatus and the sacral cornua.The knowledge of Anatomical variations of Sacral hiatus is significant while administration of Caudal Epidural Anaesthesia and  it may help to improve its success rate.

Aim:  The purpose of this study is to recognize anatomical  variations and additional landmarks of sacral hiatus in cases where the sacral cornua could not be identified and to assess proportions that may magnify the location of the apex of the sacral hiatus and thus to find a practical solution for  Caudal epidural block (CEB).

Materials and methods:  The present study was conducted on unknown  sixty one complete and undamaged adult, dry sacral bones . The material was of undetermined age and gender. Anatomical measurements was carried out on these bones using a vernier calliper to the accurate of 0.1mm.

Results: Variations in the shapes and their percentages of Sacral hiatus were observed namely Elongated, Inverted U, Irregular, Inverted V, Dumbbell and Bifid along with their distances and Angles of use in detecting the Apex were measured. The location of Apex of Sacral hiatus was found at varying levels from upper end of S2 to lower part of S5 vertebrae. Also we measured the angles between the margins of the triangle formed by the two superolateral sacral crests and the sacral hiatus. Our measurements reveal this to be an equilateral triangle.

Conclusion: This knowledge of variations in Human sacral hiatus provides a safe caudal epidural block before surgery and complications can be avoided.We believe that the equilateral character of the sacral triangle formed connecting the two posterior superior iliac spines and the apex of the sacral hiatus will be practical advantage to the clinician in ascertaining the location of the sacral hiatus during CEB.

Key words: Sarum, Sacral Hiatus, Sacral Apex, Caudal Epidural Anaesthesia.


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Cite this article: Susie Jeyalyn David. MORPHOMETRIC MEASUREMENTS OF SACRAL HIATUS IN SOUTH INDIAN DRY HUMAN SACRA FOR SAFE CAUDAL EPIDURAL BLOCK. Int J Anat Res 2019;7(3.3):6911-6917. DOI: 10.16965/ijar.2019.254