Osteoscopic Assessment of Sexual Dimorphism in Hip Bone.

Introduction: Th e pelvis is most sexually dimorphic and is the fi rst bone assessed in sex determination because it is the skeletal element most aff ected by reproduction and parturition.1 Th e assessment of the pelvis is made through metric measurements as well as through the visual analysis of non-metric traits; both important aspects of the analysis. Th e best methods for determining sex from adult skeletal remains involve measurement and inspection of the hip bone that presents a number of gender-related anatomical diff erences.2 Most osteologists visually (stereoscopic) evaluate these diff erences and integrate this subjective assessment ofhip bonemorphology into their sex determinations. Th e aim of thepresent study is to visually evaluate sexual diff erences in hip bone and comparing its effi cacy with metric assessment. Methods: Th is study is done on 46 hip bones of adult individuals of known sex from museum of department of anatomy of SGRRIM&HS Dehradun and TMMC&RC Moradabad, India. All these hip bones were visually examined and under mentioned fi ve characters of the hip bone were used, (A) aspects of the preauricular surface, (B) aspects of the greater sciatic notch, (C) the form of the composite arch, (D) the morphology of the inferior pelvis, and (E) ischiopubic proportions. Results: In this study traits of the group (A) were most sexually dimorphic while traits of the group (E) were least sexually dimorphic. Conclusion: Diagnostic accuracy is excellent when the complete hip bone is available. Hip bone features used for sex determination by visual assessment seem to be fairly stable.

Determination of sex from fragment of hip bone in Indian Bengali.

The present study was designed to derive a model for determination of sex from fragment of adult hip bone (distal ischio-pubic portion) in a population specific sample using Discriminant function analysis. The following discriminant function was obtained: DF = .76*SYL +1.60*SYW + 4.36. *DOF – 24.88 Overall 90.0 % of the cases could be correctly classified in to the two sexes from the three predictors [maximum vertical length of symphyseal surface (SYL), maximum width of symphyseal surface of pubis (SYW) and maximum diameter of the obturator foramen (DOF).] in the model. Cross-validated results showed correct classification in 86.7% cases. The results of this preliminary study show that these three variables contribute to discrimination between the two sexes in the study population. This investigation also reiterates that discriminant functions are population specific. Sexing of the adult human hipbone is thus possible with reasonable accuracy using the discriminant function on a sample obtained from the Indian Bengali population. This metric analysis can be used for fragmentary remains of hipbones of the population under study.