28 Address for Correspondence: Dr Rakesh K Verma, Additional Professor, Department of Anatomy, King George Medical University, Lucknow, Uttar Pradesh, Mobile no: 9455252213 Email - rakesh_gsvm@yahoo.co.in Date of Receiving: 12 July 2020 Date of Acceptance: 06 August 2020 0970-1842/Copyright © JAS 2020 https://doi.org/10.46351/jas.v28i1pp28-32 Original Article SIGNIFICANCE OF SACRAL INDEX IN ESTIMATION OF SEX IN NORTH INDIAN POPULATION Kanchan Bisht 1 , Rakesh K. Verma 1 , Archana Rani 1 , Navneet Kumar 1 , Baibhav Bhandari 2 1. Department of Anatomy, King George’s Medical University, Lucknow, Uttar Pradesh, India 2. Urban Community Health Centre, N.K Road, Hazratganj, Lucknow, Uttar Pradesh, India ABSTRACT Introduction: For the assessment of sexual dimorphism of human skeleton, pelvis has been used with great accuracy by anthropologists and forensic experts. Sacrum, being an integral part of pelvis, has therefore gained importance. Among the various parameters of sacrum, sacral index is the most reliable one, calculated by the formula: Sacral index=max breadth x100/max length of sacrum. This study aimed to determine the significance of sacral index in estimation of sex in north Indian population. Materials and methods: For the present study, 35 dry human sacrum bones were obtained from the Department of Anatomy, KGMU, Lucknow, out of which 32, free of deformity, were used in study. The bones were first separated as male and female on the basis of their gross features. Maximum length and breadth of sacra were measured using digital sliding Vernier calliper and sacral index was calculated. Results: Mean sacral index was significantly higher in females (109.52) as compared to males (92.37). Sex determination done on the basis of gross features were comparable to that done by calculation of sacral index, except in sacrum no. 5,13,14,15 &16. Sacrum no. 5,13,14 &15 were more curved forwards (female feature) while their sacral indices were much lesser (male feature). Sacrum no. 16 had a uniform curvature (male feature) while its sacral index was>105 (female feature). Sacrum no. 16 also had only 3 dorsal and ventral foramina, which was a variation. Conclusions: Sacral index is a reliable criterion for sex determination, useful for anatomical, medicolegal and anthropological purposes. Keywords: Dimorphism, Sacral index, Foramina, Variation, Pelvis, Anthropology