Sex estimation from radiogrametric linear dimensions of the metacarpals and phalanges in a Nigerian population

The study evaluated the sex-estimative capabilities of the digital radiogrametric linear dimensions of the metacarpals, proximal, middle, and distal phalanges of a Nigerian population. One hundred adults (50 male and 50 female) computed x-ray images of the right hand, obtained from 7 radiologic centres in different hospitals in Kwara and Lagos State were used for the study. Linear dimensions (length alone) of each bone were digitally measured (in millimetres; mm) from the apex to the base using MicroDicom Viewer (Version 3.1.4). The data were entered and managed into Microsoft excel (2016) and imported into SPSS Version 23 (IBM® Armonk, USA) for analysis. Discriminant Function Analysis (DFA) was used to evaluate the sex-discriminatory characteristics of the different bone dimensions (confidence level was set at 95 %; p < 0.05 was taken to be significant). The result showed that only the metacarpals (M_1D - M_5D) and Proximal phalanges (PP_3D - PP_5D) exhibited significant sex differences (P < 0.05), and was entered into the DFA model. (P> 0.05). The canonical correlations (CC) were 0.523 ([R2[M] = 27.3 %]; with Wilks’ Lambda Λ = 0.727, P = 0.000) and 0.428 ([R2[PP] = 18.3 %]; with Wilks’ Lambda Λ = 0.817, P = 0.002) for the metacarpals and proximal phalanges respectively. After cross-validation, accurate classification into group membership (sex) was achieved with an accuracy of 69.0 % using the metacarpals and 66.0 % using the proximal phalanges. Therefore, it can be concluded that the segregated skeletal finger dimensions are not very reliable as a stand-alone anatomical structure for sex-discrimination, but could serve as an adjunct during biological profiling in human identification.