Morphometric Analysis Sacral Hiatus of Dry Bone in Iranian Population

Abstract

Background: Caudal epidural block (CEB) has been widely used to treat lumbar spine disorders, to manage chronic low back pain, and to provide analgesia and anesthesia in operations such as labor pain and orthopedic and genital surgeries. The CEB technique depends on the precise location of the sacral hiatus (SH) through which access to the sacral epidural space is obtained. For optimal access to the sacral epidural space, accurate knowledge of the SH descriptive profile is required.
Methods: The study was performed on 23 sacrum bones. All bones were of Iranian (Persian) origin. Bones that were worn, corroded, broken, or had any anatomical problems were excluded. The parameters were measured: Sacral hiatus Length, distance between base of hiatuse-S2, liner distances between apex of sacral hiatus till right and left ends of lateral sacral crest were measured. Distance between Apex of sacral hiatus till S2, Antherio-posterior diameter of SH and location of sacral hiatus and types of SH.
Results: This study showed that the highest type of sacral hiatus in Iranians with a frequency of 38% is inverted V shape and the lowest type of deficiency shape is with a frequency of 4.8%.
The position of sacral hiatus in the Iranian sacrum showed that the highest position was with a frequency of 45% in front of the sacral vertebra 4 and the lowest case in front of the third sacral with a frequency of 15%. The height of sacral hiatus was the highest case with a height of 21-30 mm (50% or cases 9). Anterior-posterior diameter of sacral hiatus was 4-6 mm in The most common case 75% or cases 15.
It was shown that the mean distances between S2 till apex of the sacral hiatus 56.65 mm and the mean distance between S2 till base of the sacral hiatus is 36.85 mm.
Conclusion: Successful application CEB enables comfortable anesthesia for patients and helps them to resume an active life soon. Accurate understanding of the SH location is important to reduce the risk of intraoperative as well as damage to vital structures. The present study aimed to determine positional changes and measure SH distances. Also, the aim of this study was to determine SH landmark points, perform accurate and standard morphometric measurements and calculate safe SH areas in CEB application.