MRI-Based Sexual Dimorphism in Sacral Morphometry: A Forensic Study in the Central Indian Population

Background: Sex estimation is a critical component of forensic anthropology, particularly in scenarios involving incomplete or degraded skeletal remains.The sacrum, being a morphologically robust and sexually dimorphic bone, offers valuable forensic insights.Traditional techniques utilizing radiographs or dry bones are often constrained by ethical concerns and limited accessibility.Magnetic Resonance Imaging (MRI), along with CT-derived 3D imaging, provides non-invasive alternatives with high anatomical accuracy and reproducibility.This study aims to assess sexual dimorphism in sacral morphometry using MRI and CTderived 3D imaging in the central Indian population and to evaluate the diagnostic accuracy of selected morphometric parameters for reliable forensic sex estimation.Methods: A total of 80 sacra (40 male, 40 female) were analyzed using dry bone specimens and anonymized CT scan data.Morphometric parameters-including sacral index, sacral height and breadth, auricular surface width, and curvature index-were measured.Statistical analysis included t-tests, discriminant function analysis (DFA), and receiver operating characteristic (ROC) curve evaluation.Results: Significant sex-based differences were observed in sacral index, auricular surface dimensions, and curvature index (p<0.001).Discriminant analysis achieved 87.5% overall classification accuracy.The sacral index yielded the highest individual predictive power with an AUC of 0.89.Conclusion: MRI-based sacral morphometry is a reliable and non-invasive method for forensic sex estimation.The study also contributes region-specific anatomical data for the population of Madhya Pradesh, with implications for both forensic practice and clinical anatomy.