Analysis of humeral septal apertures in forensic and archaeological samples

Septal apertures (SA) are defects in the bony septum that separates the olecranon and coronoid fossae. Previous research suggests the presence of SA are highly variable between populations and generally occur at higher frequencies in females and on left humeri. Here, we analyze specimens from two modern willed body forensic collections (n = 617) and three archaeological assemblages (n = 103). Where feasible, we test for differences between sexes, sides, aperture sizes, and age distributions within self-identified racial categories and in the complete assemblage. We also present a novel assessment of SA and handedness. In brief, significant sex-based differences were found in one archaeological sample, the combined forensic sample, and the white racial category. Significant side-based differences favoring the left were found in the combined forensic and male specific sample. Significant differences in SA sizes were identified when bilaterally expressed in the forensic mixed sex sample. A test for aperture presence and hand dominance found significant differences with the majority (71%) of unilateral apertures found on the non-dominant side. Aperture presence was strongly correlated (r > 0.97) with sample size and uncorrelated with age cohorts. While high (> 40%) population-based frequencies were found in the archaeological samples similar to previous studies, a high frequency (17.8%) was also found in the white racial category exceeding most values reported for populations of European ancestry. This study contributes to the understanding of SA by providing a novel analysis of their association with handedness and provides new data on their prevalence in both archaeological and modern forensic assemblages.