Various sacral indices: role in study of sexual dimorphism

Uttama Umesh Joshi, Medha Puranik


Background: Skeleton is an excellent material in living and non-living population for genetic, anthropological and forensic investigations. Sound anatomical knowledge of human osteology in the evaluation of death may help to shed light on legal issues such as sex and age determination, parentage and racial identity. It has widely recognized that skeletal characters vary among different racial groups and even within the same racial groups. Sacrum is one of the commonest part of skeleton used to opine the sex. The study documents effort to determine sex by using different measurements of the sacrum and calculating the different indices based on these measurements. The most useful aspect of such study is to evaluate the role of different indices of sacrum in sex determination.

Methods: Study was carried out on 141 adult, dry sacra in Department of Anatomy, BVDU Medical College, Pune. 141 sacra were classified into male and female bones by observing the parameters like - length of sacrum, width of sacrum, transverse diameter of body of S1, anteroposterior diameter of S1, length of ala of sacrum.

Results: The indices like sacral index, curvature index, corpobasal index and alar Index were found to be statistically significant with p value <0.001/ <0.05. The index of body of S1 had p value >0.05 and was statistically not significant.

Conclusions: The most useful aspect of such studies was to determine appropriate indices of sexual dimorphism for sacral bone. The study concluded that no single index can identify sex of sacrum with 100% accuracy. So multiple indices should be used for determination of sex by sacrum with 100% accuracy.



Sacrum, Parameters, Indices, Sexual dimorphism

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