Sacral Hiatus - A Morphometric and Anatomical Study

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DOI: 10.21522./TIJBMS.2016.02.01.Art003

Authors : Jyothinath Kothapalli


To accurate performance of epidural anaesthesia and analgesia it is important to know the variations of sacral hiatus in dry bone. The present observational study conducted on one hundred dry human sacra to evaluate the anatomical and morphometric variations of sacral hiatus. The most common shape of sacral hiatus was inverted ‘U’ and ‘V’ respectively. Apex of sacral hiatus present at 3rd sacral segment in 78% sacra and base is at fifth sacral segment in 89% sacra. The length of sacral hiatus is between 11-20 mm in majority sacra, anteroposterior diameter is 4-6 mm in 63% sacra and transverse diameter is 11-15 mm in of sacral hiatus. Anatomical variations in sacral hiatus can leads to caudal epidural anaesthesia failure and procedure related complications. Understanding these variations may improve success of caudal epidural anaesthesia and decrease incidence of complications.

Keywords: Sacral hiatus, caudal epidural anaesthesia, Morphometry.


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