Width of Sternum at Suprasternal Notch and at the Level of Fourth Rib for Determination of Sex in the Population of Delhi: A New & Reliable Tool for Sex Prediction

Abstract

Determination of sex of a person is an important aspect of identification and is required in the living as well as the dead. The sternum bone on its own has shown considerable sexual dimorphism and its various dimensions have been used for this purpose. Studies have shown significant sexual variation in the length and width of the sternum. This study was conducted to find out sexual variation in the width of the sternum at the level of 4th rib (WS4) and at the suprasternal notch (WSN). Though variation in width at different levels of the sternum have been studied but variations at all levels has not been explored in the past. We also studied the sternum in two states viz. the wet state i.e the freshly removed (F) and dry state i.e after processing the sternum (D). One hundred sternums with equal sex distribution were studied. The discriminant function analysis from sternum for sex variation using the combined width (WS4 + WSN) was quite high, ranging from 69% for wet sternum and 64% for dry sternum. These measurements were found to be more accurate in case of females, where the accuracy for sex determination was the highest for WS4 (D;76%), followed by WSN (F; 72%), followed by WS4 (F; 68%), and by WSN (D;66%), respectively. In males, the discrimination function was the highest with WSN in both wet and dry specimens, 64%, followed by WS4 (D; 62%) and WS4 (F; 60%), respectively. We concluded that determination of sex by means of width of sternum at supra-sternal notch and 4th rib is a reliable indicator in both wet and dried state of the bone having higher accuracy rate with examination of wet sternum and in case of females.