Sex Determination by using Morphometric Analysis of Foramen Magnum: An Autopsy Based Study in Western Rajasthan
DOI:
https://doi.org/10.48165/jfmt.2026.43.03.06Keywords:
Foramen Magnum, Sex Determination, Morphometry, Forensic Identification, Autopsy, Western RajasthanAbstract
Introduction: Sex determination is a crucial component of personal identification in forensic investigations, especially when skeletal remains are fragmented, decomposed, burnt, or mutilated. The foramen magnum, owing to its protected anatomical location and resistance to postmortem damage, serves as a valuable structure for anthropometric assessment. The present study was undertaken to evaluate the usefulness of morphometric analysis of the foramen magnum in sex determination among the Western Rajasthan population.
Methodology: A cross-sectional observational study was conducted in the Department of Forensic Medicine and Toxicology, S.P. Medical College and PBM Hospital, Bikaner, from March 2025 to August 2025. A total of 282 medicolegal autopsy cases aged 20–65 years fulfilling the inclusion criteria were included. Following standard autopsy procedures, the foramen magnum was exposed and its maximum anteroposterior length (FML) and transverse width (FMW) were measured using a digital inside pistol caliper. The area of the foramen magnum (FMA) was calculated using Radinsky’s formula, and the foramen magnum index (FMI) was derived. Statistical analysis was performed to compare morphometric parameters between males and females.
Results: Among the 282 subjects, 234 (83.0%) were males and 48 (17.0%) were females. The mean FML, FMW, and FMA were significantly higher in males than females. In males, mean FML, FMW, and FMA were 34.1 mm, 28.6 mm, and 766 mm² respectively, whereas in females these values were 31.7 mm, 26.8 mm, and 667 mm² respectively. The foramen magnum index showed minimal sex-related variation. These findings demonstrated significant sexual dimorphism in the morphometric dimensions of the foramen magnum.
Conclusion: Morphometric measurements of the foramen magnum, particularly its length, width, and area, exhibit significant sexual dimorphism and can serve as useful adjuncts in sex determination. The study supports the utility of foramen magnum morphometry as a reliable supplementary tool for forensic identification in the Western Rajasthan population.
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