Determination of sexual dimorphism from the proximal femur in a heterogeneous North American population

Abstract

Many studies support the use of population specific standards to establish sexing of skeletal remains. Classic collections, which have been used to establish population standards, may not be reflective of modern societies, which are frequently composed of multiple ethnicities. In this study, vertical head diameter (VHD), superior-inferior neck diameter (SID), hip axis length (HAL) and neck-shaft angle (NSA) were measured from the proximal femur in order to determine if dimorphism can be established in a heterogeneous, contemporary population. Radiographic images from 159 males and 293 females were sampled. Comparisons using a two-tailed t-test indicated significant differences between males and females for all 4 variables. Sexual dimorphism indexes indicate strong dimorphism for VHD, SID, and HAL (113.26, 117.58 and 112.47 respectively) but lack of dimorphism for NSA (99.17). Discriminant function analysis indicated VHD to be the most sexually dimorphic feature. Sexing using all 4 variables resulted in 85.4% accuracy. Of the 159 males, 27 were incorrectly classified leading to 83.0% sexing accuracy for males. Of the 293 females, 39 were incorrectly classified leading to 86.7% sexing accuracy for females. The results of this study suggest that population specific standards are not necessary when sexing based on contemporary skeletal remains.