An Anthropological Examination of the Types of Skeletal Fractures Resulting from Fatal High (˃3 m) Free Falls,

Fatal falls from heights (?3 m) often result in blunt force trauma (BFT) to the skeleton. The fracture patterns that result from this BFT mechanism are well understood in forensic anthropology and forensic pathology; however, details of the specific types of fractures that result remain poorly documented. The aim of this study was to provide a detailed examination of the types of fractures that may result from fatal high falls. Fractures were recorded from 95 full‐body postmortem computed tomography scans of individuals known to have died from a high fall. Trauma was then analyzed taking into account the extrinsic and intrinsic variables known to influence a fall using multiple logistic regression. A total of 339 types of fractures were classified, of which 16 were significantly associated with this BFT mechanism. Classified fracture types will augment anthropological interpretations of the circumstances of death from BFT in cases of suspected high falls.     

Skeletal Trauma Resulting From Fatal Low (≤3 m) Free Falls: An Analysis of Fracture Patterns and Morphologies

The skeletal trauma resulting from fatal low (≤3 m) free falls is poorly researched and understood by forensic practitioners. The aim of this study was to identify the types of skeletal trauma resulting from low falls through investigating fracture patterns and morphologies. Skeletal trauma was analyzed using full‐body postmortem computed tomography scans of 145 individuals who died from a low free fall. Trauma was then contextualized to the variables that influence how a person falls using multiple logistic regression. Results showed fracture patterning primarily involved the axial skeleton and that there were a number of patterns significantly associated with the height fallen, pre‐existing health conditions, and age. Analysis of fracture morphologies showed 108 possible fracture types, six of which were significantly associated with the height fallen. Understanding the skeletal trauma characteristic of low free falls will further inform anthropological interpretations of trauma in cases where a fall may be considered the possible mechanism.     

An Improved Equation for TBS and ADD: Establishing a Reliable Postmortem Interval Framework for Casework and Experimental Studies

Megyesi et al.'s (J Forensic Sci, 2005, 50, 618) paper was important to forensic anthropology as it introduced a quantitative framework for estimating time since death in human cadavers, based upon physical appearance by way of scoring on a novel scale. However, errors concerning rounding, temperature scale, and incorrect use of a statistical regression model render their predictive formula unusable. Based upon only their more reliable data, a more appropriate regression model to predict accumulated degree days (ADD) from total body score (TBS) is presented. The new model is also a superior fit (r² = 0.91) and produces markedly narrower confidence intervals than the original, which also allowed impossible, negative ADD values. Explanations of the shortcomings in the original analysis and calculations are presented, which it is hoped will help forensic scientists avoid making similar mistakes.     

Fatal Falls from Height in Taiwan

This study conducts an investigation of fatal falls from height, examines gender differences, and compares our findings with those of Western countries. We review deaths in Taiwan caused by falls from height that underwent forensic autopsy from 1994 to 2010. Among the examined cases, 182 were suicide, 156 were accidents, and 18 were homicides. Men who fell from greater heights had a lower probability of fatal head trauma (p = 0.045), and women exhibited a lower fatal head trauma rate when falling from heights of between 10 and 25 m in accident group (p = 0.003). There was no significant difference between cases of falling from greater and lower heights within the suicide group (p = 0.834). Psychiatric illness was only reported in 20.3% and 28.8% cases in suicide and accident groups. Only in male cases was the use of psychotropic substances higher in the suicide groups than in the accident groups (p = 0.047).     

Effect of Wind on Horizontal Displacement of Fatal Fall from a Height

The horizontal displacement of the human body resulting from fatal fall from a height is an important variable commonly used to inversely determine the cause or identify other forensic aspects of the fall. When examining the horizontal displacement, the wind effect is generally ignored. This technical note reports analytical modeling of the falling process, utilizing previous measurements of wind force acting on the human body, for determining the functional relationship between the wind speed and the horizontal displacement in the falling process. The result reveals that it does not take extremely rare wind conditions to cause a considerable shift of the human body, highlighting the importance to consider wind as a factor in investigations of fatal falls.     

Validation of a new method of providing case-specific time-of-death estimates using cadaver temperatures

The near ubiquitous presence of numerical simulation has made case-specific calculations of body temperatures following death possible so that accurate calculations of body temperatures can provide valuable information for estimating the time of death and can aid in forensic investigations. Here, a computational approach is described that has been validated against multiple, independent, and experimental investigations. The approach only requires one subjective input parameter (the heat transfer coefficient). A simple algorithm serves as a guidepost to the selection of this parameter. The algorithm incorporates clothing and the space in which the body is housed. Heat transfer coefficients that range from h = 2 W/m²/°C for bodies that are heavily clothed to h = 9 W/m²/°C for bodies that are nude (in air). The method also requires setting of ambient temperature conditions (ambient temperature)—however, that input is often available. The paucity of inputs makes this technique remarkably easy to employ. The new method is also able to calculate cadaver cooling rates for situations where the cadaver is in a timewise or spatially changing thermal environment (diurnal temperature variations, bodies partially submerged in water, changes to weather, insolation, etc.). Results from the present calculations are compared with a large body of measurements from the literature; it was found that the predictions and measurements were in excellent agreement, regardless of the ambient temperature conditions and the nature of the clothing of the body. This new calculation approach can be used with reasonable accuracy for determining cadaver cooling and time since death.     

有限元方法在法医学颅脑损伤分析中的应用

有限元方法(finite element method,FEM)是一种与现代计算机技术相联系的计算应力分析方法,已逐渐被应用于生物力学领域仿真人体结构力学功能研究,尤其是在颅脑损伤研究中最为广泛和深入。本文综述了现有头部有限元模型的特点、材料属性的赋值以及颅脑损伤有限元模型在钝力击打、高坠、交通事故等鉴定中的应用情况,探讨FEM建模在法医学颅脑损伤预测中的优劣势及其应用价值。     

有限元方法在法医损伤鉴定中的应用

有限元方法（finite element method,FEM）是一种与现代计算机技术相联系的计算应力分析方法,已逐渐成为生物力学领域仿真人体结构力学功能研究的一个重要实验手段,可以有效地分析人体结构的物理性质,如受外力作用时人体组织的外部冲击响应及内部应力分布等,在法医损伤学研究及实践鉴定过程中具有较高的应用价值。文章综述了利用有限元方法分析高坠、交通及火器事故中颅脑损伤、脊柱损伤、骨盆损伤等的成伤机制、损伤生物力学等研究领域的成果,探讨其在法医损伤学研究以及法医检案中的应用价值。     

246例高坠案件中坠落高度与损伤分析

目的对高坠案件进行统计分析,为相关鉴定研究提供参考。方法收集上海市浦东地区最近十年来记录有坠落距离的246例高坠案件,对人体损伤的特点进行比较分析。结果自杀高坠的高度显著高于意外高坠的高度(25.70m:13.98m);所有高坠中,头部损伤概率较高(75.2%),颈部损伤概率较低(6.5%);意外高坠的头部损伤概率高于自杀组(89.4%:75.2%)。结论意外高坠的死者比自杀高坠的死者更缺乏四肢对于头部的保护;过低的颈部损伤发现率提示国内法医工作者应该更加重视在高坠案件中的对于颈部损伤的检查。     

Investigating Residential History Using Stable Hydrogen and Oxygen Isotopes of Human Hair and Drinking Water

The relationship between isotopic signals in human hair and geographic region has potential forensic applications for identifying unknown individuals' place of recent residence. This study analyzes δ²H and δ¹⁸O isotopes in residential tap water and bulk hair samples from 17 volunteers representing 12 locations in Ontario, Canada. There is a strong correlation (R² = 0.9) between δ²H and δ¹⁸O values of the water samples. In contrast, the δ²H and δ¹⁸O values of the hair samples are weakly correlated (R² = 0.3), and the greater variability in the data is linked to dietary factors. This study demonstrates that the δ²H and δ¹⁸O values of hair and drinking water can be used to help identify potential place of residence in forensic cases, particularly in relation to proximity to large bodies of water such as the Great Lakes, but interpretations are complicated by the contribution of both water and diet to δ²H and δ¹⁸O values in hair.     

Soil Fungi: Their Potential use as a Forensic Tool

As a grave is an anomalous environment and differs from its surroundings, criminal investigators employ different techniques for locating, recovering, and analyzing clandestine graves. In this study were identified the fungi found in the soil under corpses in decomposition with an aim at relating the copresence of human remains and different fungal species. Were isolated the fungi in three ways: soil washing, serial dilutions, and moist chamber growth. Dichotomomyces cejpii, Talaromyces trachyspermus, Talaromyces flavus, and Talaromyces sp. were the representative species found—with those belonging to the ammonia group, whose fungi are the first in the succession of cadaver decomposition directly in the ground. The mycobiota found at the present study area clearly differs to mycobiota identified in control sample and from previously described species for other areas of Buenos Aires Province, Argentina. Further forensic examples of this type are needed to develop fully the detailed use of mycology as a forensic tool.     

Positive Dental Identification Using Tooth Anatomy and Digital Superimposition

Dental identification of unknown human remains continues to be a relevant and reliable adjunct to forensic investigations. The advent of genomic and mitochondrial DNA procedures has not displaced the practical use of dental and related osseous structures remaining after destructive incidents that can render human remains unrecognizable, severely burned, and fragmented. The ability to conclusively identify victims of accident and homicide is based on the availability of antemortem records containing substantial and unambiguous proof of dental and related osseous characteristics. This case report documents the use of digital comparative analysis of antemortem dental models and postmortem dentition, to determine a dental identification. Images of dental models were digitally analyzed using Adobe Photoshop^TM software. Individual tooth anatomy was compared between the antemortem and postmortem images. Digital superimposition techniques were also used for the comparison. With the absence of antemortem radiographs, this method proved useful to reach a positive identification in this case.     

An Experimental Study of Vertebrate Scavenging Behavior in a Northwest European Woodland Context

Vertebrate scavengers can modify surface deposited human remains which can hinder forensic investigations. The effects of such scavenging vary between species and regions. Published research into the effects of the scavenging of human remains is dominated by work from North America with few studies covering Northwestern Europe. Forensic scientists, investigators, and police search officers in Northwestern Europe are often left questioning on a basic level as to which scavengers are active and how they might affect human remains. This paper presents the results of a field study utilizing deer (Cervus nippon; Capreolus capreolus) as surface deposits observed by motion detection cameras in a British woodland. The most common avian and rodent scavenger species recorded included the buzzard (Buteo buteo), carrion crow (Corvus corone), wood mouse (Apodemus sylvaticus), and gray squirrel (Sciurus carolinensis). The scavenging behaviors observed were affected by seasonality, rates of decomposition, and insect activity. Scavenging by buzzards, unlike carrion crows, was most frequent during fall to winter and prior to insect activity. Overall, avian scavengers modified and scavenged soft tissue. Rodents scavenged both fresh and skeletonized remains with gray squirrels only scavenging skeletal remains. Wood mice were most active in winter and scavenged both soft tissue and bone.     

Whole Plastome Sequences of Two Drug-Type Cannabis: Insights Into the Use of Plastid in Forensic Analyses

DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.     

Comparative Analysis of Insect Succession Data from Victoria (Australia) Using Summary Statistics versus Preceding Mean Ambient Temperature Models

Minimum postmortem interval (mPMI) can be estimated with preceding mean ambient temperature models that predict carrion taxon pre‐appearance interval. But accuracy has not been compared with using summary statistics (mean ± SD of taxon arrival/departure day, range, 95% CI). This study collected succession data from ten experimental and five control (infrequently sampled) pig carcasses over two summers (n = 2 experimental, n = 1 control per placement date). Linear and exponential preceding mean ambient temperature models for appearance and departure times were constructed for 17 taxa/developmental stages. There was minimal difference in linear or exponential model success, although arrival models were more often significant: 65% of linear arrival (r² = 0.09–0.79) and exponential arrival models (r² = 0.05–81.0) were significant, and 35% of linear departure (r² = 0.0–0.71) and exponential departure models (r² = 0.0–0.72) were significant. Performance of models and summary statistics for estimating mPMI was compared in two forensic cases. Only summary statistics produced accurate mPMI estimates.     

Estimating Time Since Death from Postmortem Human Gut Microbial Communities

Postmortem succession of human‐associated microbial communities (“human microbiome”) has been suggested as a possible method for estimating postmortem interval (PMI) for forensic analyses. Here we evaluate human gut bacterial populations to determine quantifiable, time‐dependent changes postmortem. Gut microflora were repeatedly sampled from the proximal large intestine of 12 deceased human individuals as they decayed under environmental conditions. Three intestinal bacterial genera were quantified by quantitative PCR (qPCR) using group‐specific primers targeting 16S rRNA genes. Bacteroides and Lactobacillus relative abundances declined exponentially with increasing PMI at rates of N_t = 0.977e^?0.0144t (r² = 0.537, p < 0.001) and N_t = 0.019e^?0.0087t (r² = 0.396, p < 0.001), respectively, where N_t is relative abundance at time (t) in cumulative degree hours. Bifidobacterium relative abundances did not change significantly: N_t = 0.003e^?0.002t (r² = 0.033, p = 0.284). Therefore, Bacteroides and Lactobacillus abundances could be used as quantitative indicators of PMI.     

Traveling There and Back Again: A Fingernail's Tale

This study focuses on the examination of stable isotope biomarkers in human fingernails of travelers who ventured away from Salt Lake City, UT and subsequently returned. Here, we describe three case studies examining: individual travelers (n = 4), paired travelers (n = 2), and a traveler (n = 1) who repeatedly left and returned. Our case studies examined the influences of dietary and drinking water inputs on fingernail stable isotope profiles for reconstructing travel histories. Stable isotope data were compared with theoretical and predictive models that laid the groundwork for anthropological and forensic geospatial reconstruction of travel histories. Drinking water inputs strongly influenced stable isotope profiles and the patterns observed were consistent with reported travel histories. Finally, observed fingernail stable isotope ratio data were consistent with modeled rates of stable isotope turnover and transition to expected values for the new environment. The results of our study further support the use of fingernail tissues for travel history reconstruction.     

A Test of the Passalacqua Age at Death Estimation Method Using the Sacrum

A test of the accuracy of the Passalacqua (J Forensic Sci, 5, 2009, 255) sacrum method in a forensic context was performed on a sample of 153 individuals from the J.C.B. Grant Skeletal Collection. The Passalacqua (J Forensic Sci, 5, 2009, 255) method assesses seven traits of the sacrum using a 7‐digit coding system. An accuracy of 97.3% was achieved using the Passalacqua (J Forensic Sci, 5, 2009, 255) method to estimate adult skeletal age. On average each age estimate differed by 12.87 years from the known age. The method underestimated the age of individuals by an average of 4.3 years. An intra‐observer error of 6.6% suggests that the method can be performed with precision. Correlation and regression analysis found that the sacral traits used in the Passalacqua (J Forensic Sci, 5, 2009, 255) method did not have a strong relationship with age or an ability to strongly predict age. Overall, the method was not practical for use in a forensic context due to the broad age ranges, despite the high accuracy and low intra‐observer error.     

An Update on the Hazards and Risks of Forensic Anthropology,Part II: Field and Laboratory Considerations

This paper focuses on potential hazards and risks to forensic anthropologists while working in the field and laboratory in North America. Much has changed since Galloway and Snodgrass published their seminal article addressing these issues. The increased number of forensic practitioners combined with new information about potential hazards calls for an updated review of these pathogens and chemicals. Discussion of pathogen hazards (Brucella, Borrelia burgdorferi, Yersinia pestis, Clostridium tetani and West Nile virus) includes important history, exposure routes, environmental survivability, early symptoms, treatments with corresponding morbidity and mortality rates, and decontamination measures. Additionally, data pertaining to the use of formaldehyde in the laboratory environment have resulted in updated safety regulations, and these are highlighted. These data should inform field and laboratory protocols. The hazards of working directly with human remains are discussed in a companion article, “An Update on the Hazards and Risks of Forensic Anthropology, Part I: Human Remains.”     

Ruptured Syphilitic Aneurysm: A Cause of Sudden Death in a Man with Human Immunodeficiency Coinfection

Syphilis, a sexually transmitted infection caused by the bacterium Treponema palladium, is experiencing a worldwide resurgence. The risk of syphilis infection is particularly high in men who have sex with men (MSM), especially those who are human immunodeficiency virus (HIV)‐positive. Untreated syphilis can lead to rare but severe late‐stage complications, including syphilitic aortitis. Herein, we present an autopsy case of a ruptured thoracic aneurysm that resulted from an undetected case of syphilitic aortitis in an HIV‐positive Japanese MSM with undiagnosed syphilis. Although no syphilitic skin lesions were observed on the body, anatomical changes consistent with a syphilitic etiology were present at the site of the rupture, including medial aortic scarring with “tree‐bark”‐like atherosclerotic plaque. In addition, heart blood was positive for T. palladium in a latex agglutination test. This case highlights for forensic pathologists the importance of recognizing syphilis as a possible underlying cause of sudden death among HIV‐positive MSM.