Morphological analysis of sacral hiatus variations and their relevance in caudal epidural Anesthesia
DOI:
https://doi.org/10.30750/ijpbr.14.4.14Keywords:
Sacral hiatus; Morphometric analysis; Anatomical variations; Caudal epidural anesthesia; Computed tomography; Sacral canal; Regional anesthesia; Retrospective study.Abstract
Background: Variations in the morphology of the sacral hiatus are clinically important because they may influence the success and safety of caudal epidural anesthesia. Knowledge of sacral hiatus anatomy is essential for accurate needle placement and prevention of procedural complications.
Objective: To evaluate morphological variations of the sacral hiatus and assess their relevance in caudal epidural anesthesia using retrospective computed tomography records.
Methods: A retrospective observational study was conducted at Anugrah Narayan Magadh Medical College and Hospital (ANMMCH), Gaya, over one year. CT scans of the pelvis and lumbosacral region from 200 adult patients were analyzed. Sacral hiatus shape, length, transverse width, anteroposterior diameter, and vertebral level of the apex and base were recorded. Associations with predicted difficult caudal epidural access were evaluated using Chi-square test, independent t-test, and logistic regression analysis.
Results: The inverted U-shaped sacral hiatus was the most common morphology (37.0%), followed by the inverted V shape (28.0%). Mean sacral hiatus length, transverse width, and anteroposterior diameter were 24.6 ± 5.1 mm, 13.2 ± 2.8 mm, and 5.6 ± 1.4 mm, respectively. The apex was most frequently located at S4 (48.0%). Male participants had significantly larger morphometric measurements than females (p < 0.01). Predicted difficult caudal epidural access was identified in 23.0% of cases. Narrow transverse width (AOR 3.94, p < 0.001), reduced anteroposterior diameter (AOR 2.86, p = 0.013), and irregular or bifid morphology (AOR 3.51, p = 0.002) were independent predictors of difficult access.
Conclusion: Substantial anatomical variability exists in the sacral hiatus. Pre-procedural recognition of these variations may improve the success and safety of caudal epidural anesthesia and reduce technical difficulty during needle placement.
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