Ilium growth study: applicability in sex and age diagnosis

The use of coxal elements for age and sex diagnosis from the skeleton is the primary and most widespread way of bringing us closer to the identity of dead individuals in archaeological and certain forensic scenarios. Diagnosis in sub-adults, especially in fetus and infant age, is not clear; and further studies are needed. This work presents the analysis of the growth of six variables in the ilium, from birth to 97 years of age, in order to evaluate its significance and its capacity for age and sex determination during and after growth. The materials used were 327 specimens from four documented Western European collections. Growth curves were calculated for the three classical variables of the ilium (width, length and index) and three new variables of the acetabulum area (horizontal and vertical diameter of the ilium acetabular surface and the ilium acetabular index). None of the curves showed a lineal growth, except those of the horizontal diameter of the ilium acetabular surface for the male series. The ilium width has the most complicated growth and it is explained by a four-degree polynomial. All the variables studied can be useful for adult sex discrimination with the exception of the ilium width and ilium acetabular index. Furthermore, the most useful variables for subadult and adult age estimation in archaeological samples, as well as in forensic samples, are the absolute measurements (ilium length and width, horizontal and vertical diameter of the ilium acetabular surface); however, the ilium width is the best variable, as this can be applied to all growth ages using both sexual series together up to 20 years of age.