Traumatic lesions on human skeletal remains are widely used for reconstructing past accidents or violent encounters and for comparing trauma prevalence across samples over time and space. However, uncertainties in trauma prevalence estimates increase proportionally with decreasing skeletal completeness, as once-present trauma might have gone missing. To account for this bias, samples are typically restricted to skeletal remains meeting a predefined minimum completeness threshold. However, the effect of this common practice on resulting estimates remains unexplored. Here, we test the performance of the conventional frequency approach, which considers only specimens with ≥ 75% completeness, against a recent alternative based on generalized linear models (GLMs), integrating specimen completeness as a covariate. Using a simulation framework grounded on empirical forensic, clinical, and archaeological data, we evaluated how closely frequency- and GLM-based estimates conform to the known trauma prevalence of once-complete cranial samples after introducing increasing levels of missing values. We show that GLM-based estimates were consistently more precise than frequencies across all levels of incompleteness and regardless of sample size. Unlike GLMs, frequencies increasingly produced incorrect relative patterns between samples and occasionally failed to produce estimates as incompleteness increased, particularly in smaller samples. Consequently, we generally recommend using GLMs and their extensions over frequencies, although neither approach is fully reliable when applied to largely incomplete samples.

This study characterizes patterns of cranial trauma prevalence in a large sample of Upper Paleolithic (UP) fossil specimens (40,000-10,000 BP).

Our sample comprised 234 individual crania (specimens), representing 1,285 cranial bones (skeletal elements), from 101 Eurasian UP sites. We used generalized linear mixed models (GLMMs) to assess trauma prevalence in relation to age-at-death, sex, anatomical distribution, and between pre- and post-Last Glacial Maximum (LGM) samples, while accounting for skeletal preservation.

Models predicted a mean cranial trauma prevalence of 0.07 (95% CI 0.003-0.19) at the level of skeletal elements, and of 0.26 (95% CI 0.08-0.48) at the level of specimens, each when 76-100% complete. Trauma prevalence increased with skeletal preservation. Across specimen and skeletal element datasets, trauma prevalence tended to be higher for males, and was consistently higher in the old age group. We found no time-specific trauma prevalence patterns for the two sexes or age cohorts when comparing samples from before and after the LGM. Samples showed higher trauma prevalence in the vault than in the face, with vault remains being affected predominantly in males.

Cranial trauma prevalence in UP humans falls within the variation described for Mesolithic and Neolithic samples. According to our current dataset, UP males and females were exposed to slightly different injury risks and trauma distributions, potentially due to different activities or behaviors, yet both sexes exhibit more trauma among the old. Environmental stressors associated with climatic changes of the LGM are not reflected in cranial trauma prevalence. To analyze trauma in incomplete skeletal remains we propose GLMMs as an informative alternative to crude frequency calculations.

Human skeletal remains of an adult male (20-24 years old) and a juvenile (4-8 years old), dated to 750 ± 85 ¹⁴C years BP, were found on the southern margin of Mar Chiquita Lagoon (Córdoba, Argentina). Both individuals show signs of being victims of interpersonal violence, with arrowheads associated with the remains and perimortem lesions on the juvenile, as well as an unusual form of burial, with the juvenile partially overlapped with the adult. The aim of this work is to study a possible kin relationship between these two individuals through ancient DNA analysis. Biological kinship was evaluated by autosomal and Y-chromosome STR (short tandem repeat) typing, PCR-APLP for SNP determination and hypervariable region I sequencing of the mitochondrial DNA. Genetic analyses indicated that these individuals shared the same Y-chromosomal haplotype but different mitochondrial lineages. The likelihood ratio based on autosomal loci indicates that the genetic profiles of the human remains would be more likely to be that indicating a father-son bond. The paleogenetic approach combined with forensic genetic methods applied to this study allowed us to confirm a hypothesis that originated in bioarchaeological evidence. This study constitutes a unique case in Argentina of kinship determination based on DNA profiles of human remains in an archaeological context of interpersonal violence. It is important to highlight the contribution made by these studies to address topics usually hidden in bioarchaeological studies, such as community organization, cultural customs and mortuary practices.

This work describes a new method for recording nasal fracture in skeletonized individuals, suitable for use in biocultural studies of violence and fracture in past societies.

The method consists in recording the 'side of fracture', 'side of deviation', 'type of fracture', 'other facial fractures', and stage of 'bone remodeling'.

A lateral impact force to the facial area is typical of interpersonal violence. This may result in a unilateral nasal fracture and/or a laterally deviated nose. Given the predominance of right-handedness in human populations, side of fracture and, especially, side of deviation, may be useful indices of interpersonal violence. As regards fracture type, although a distal fracture of the nasal bones is the most common type, their comminution may be associated with higher impact forces. The presence of other facial fractures may also be an indicator of high-energy impacts.

Different patterns of nasal trauma may be consistent with different etiologies.

The method is focused at improving our ability to distinguish the direction and type of impact that caused the injury and, in particular, whether, at a population or sub-group level, such injuries are likely to be predominantly due to violence or to other causes.

Well healed fractures of the nasal bones or injury to the septum may be difficult to identify. Also, it is not possible to confirm if nasal and other facial fractures are temporally concurrent.

To test this method using skeletal collections with known trauma history or 3D prints of modern nasal injuries of known etiologies.

This study explores the differences in frequency and type of trauma found in two Medieval cemeteries in Denmark, as well as the cultural and community implications of those differences.

We examined 235 skeletons from the cemetery at Tjærby (rural) and 170 skeletons from the cemetery at Randers (urban) for trauma from the Medieval period in Denmark, 1050 to 1536 CE.

Trauma was assessed through macroscopic examination and odds ratio and relative risk assessments were run to assess the difference in trauma.

There was no significant difference in the presence of trauma between the rural and urban cemeteries or between males and females. There were some significant differences in relative risk for trauma between the two cemeteries.

The division and variation in trauma between the two cemeteries is most likely related to differences in economy and occupation.

There are relatively few studies that examine the difference in inherent risk of trauma between rural and urban Medieval communities, especially in Denmark. This research also adds to the growing body of literature in paleopathology that uses epidemiology to explore the parallels between patterns of trauma and community lifeways.

The cemeteries are approximately 5 km distance from each other so similarities in the sample could be a result of location.

A wider sample of Medieval cemeteries in Denmark needs be added to this analysis to provide a more complete picture of trauma patterns during this time period.