Osteometric sorting of metacarpals and metatarsals in commingled human skeletal assemblages

Commingling of human skeletal remains impedes anthropological analyses. Therefore, researchers must develop methods for individuating remains. One such method is osteometric sorting, but most studies have not included frameworks for resolving commingling of hand and foot elements, such as metacarpals and metatarsals. This study uses a reference sample from the University of New Mexico’s documented osteological collection to derive that data. Hypotheses relating to the concepts underlying osteometric sorting of paired, articulating, and other regions were tested, including (1) metacarpals and metatarsals show symmetry through no significant size differences between rights and lefts, (2) the lengths of facets where metacarpals and metatarsals articulate are correlated, and (3) metacarpal and metatarsal dimensions are correlated with humerus and femur dimensions. Statistical data for osteometric sorting was then derived, tested, and applied to the historic Point San Jose Collection to discern various types of medical discard that could explain its origin. Most hypotheses were accepted, but symmetry for the metacarpals was rejected due to a right directional asymmetry that may reflect handedness of the population. The minor right-left differences did not prevent the application of osteometric pair-matching, which was powerful for sorting. Osteometric articulation and osteometric comparisons to the humerus and femur were moderately successful. The application of the methods to the Point San Jose collection suggests the presence of cadavers rather than surgical waste. While refinements of measurements and a larger, more diverse reference sample would improve the method, this study shows the utility of sorting metacarpals and metatarsals using osteometric methods.