Caudal anesthesia involves needle penetration through the sacral hiatus into the sacral canal. In adults, the sacrum is a triangular bone formed from the fusion of five sacral vertebrae. It differs in neonates and infants due to delayed myelination and fusion of vertebrae. The sacral hiatus is wider in children, allowing easier identification and catheter insertion for caudal anesthesia. Regional techniques require lower approaches in pediatrics due to the lower termination of the spinal cord and dural sac.