Application of Purkait's triangle method on a skeletal population from southern Europe.

The existence of sexual dimorphism in individual elements of the human skeleton allows sex determination and significantly enhances the identification of fragmentary skeletal material. Traditionally, the pelvis and the skull are used for an accurate sex determination. Sometimes they are not available and alternative methods have to be used. The aim of this work is to study the sexual dimorphism of the proximal portion of the posterior femur by analyzing the biometric data of the Purkait's triangle. The studied sample comprises 203 individuals (112 males and 91 females) from the Modern Human Skeletal Reference Collection (The Athens Collection) of the Department of Animal & Human Physiology (National & Kapodistrian University of Athens). The biometric data were analyzed by Discriminant Analysis and equations were generated for sex determination, which gave an overall correct classification of 78.3%. For the right and the left femur the percentages of correct classification were 77.8% and 75.9% respectively. These accuracy rates were compared to those of an Indian population and were found to be lower (86.5% for males and 86.3% for females). The study of sexual dimorphism (SD) in Greek, Indian, European-American and African-American populations gave interesting results. The AB diameter in the Greek sample shows the lowest degree of SD while the AC diameter shows the highest. In the other three population samples, the BC diameter shows the highest degree of SD. We assume that the femur anatomy of the Greeks is the major cause that the Purkait method does not give high rates of correct classification. It is therefore advisable that practitioners exercise caution when using this method on skeletal material from Greece, especially in forensic contexts.