Sex assessment based on clavicular measurements in a modern Japanese population using multidetector computed tomography

Abstract

Accurate sex estimation from unknown human remains is crucial as an integral and foremost step toward individual identification. The aims of this study were to assess sexual dimorphism of the clavicle and develop discriminant equations for sex estimation in a modern adult Japanese population based on clavicular measurements using three-dimensional (3D) computed tomographic (CT) images. A total of 300 cadavers (150 males, 150 females) of known age and sex that underwent postmortem CT and subsequent forensic autopsy were obtained. Four measurements were performed using 3D CT reconstructed images that extracted only bones based on the CT values, as follows: the linear distances between the medial superior margins of the left and right sternal facets to the lateral points of the left and right acromial ends, and the linear distances between the medial superior margins of the left and right sternal facets to the tips of the left and right conoid tubercles. The mean values of all measurements were significantly greater for male subjects than female subjects. Univariate discriminant function analysis (DFA) provided correct sex prediction rates of 88.3–92.2%. Stepwise DFA for the left and right clavicles yielded sex classification accuracy rates of 92.2% and 91.0%, respectively. In conclusion, clavicular measurements using 3D CT images of a contemporary Japanese population may be useful for sex estimation in forensic contexts.