Numerous recent studies address the use of metacarpals in the determination of sex and race. However, most of these studies rely on multiple measurements of metacarpal bone robusticity, which are affected by lifestyle activity and can mask underlying racial and sexual dimorphism. Measurements of length, however, are arguably less affected by these factors. The present study investigates the utility of metacarpal length, to the exclusion of other measures of shape and size, in sex and race determination. Two criteria for utility are established: (1) metacarpal length has enough power of discrimination to accurately predict sex, and (2) the analysis of metacarpal length measurements can simultaneously assign sex and race, without the necessity for additional bone inclusion.

Using a sample (n=100) of black and white males and females, maximum axial length measurements were taken for right and left hand metacarpals. Pooled, race-specific, and sex-specific discriminant functions were generated for sex and race determination. Functions were then applied to a second sample (n=20) to establish their degree of accuracy. The highest cross-validated accuracy rate was generated from male right metacarpals using sex-specific discriminant functions in race determination (80–88%, cross-validated). Sex-specific race determination functions also produced the lowest accuracy rate when applied to left female metacarpals (44–68%, cross-validated). Overall, accuracy rates for sex (71.17%, cross-validated) and race (72%, cross-validated) determination were lower than previous studies, suggesting that metacarpal bone length, as a variable, is not robust enough to stand on its own in sex and race determination.