Forensic age estimation of the knee by post-mortem DR, CT, and MR imaging: a comparative study.

It is believed by many that reference data for age estimation purposes must be imaging-modality specific. A study from our department has however proven otherwise. We therefore found it interesting to investigate this further by looking at the level of agreement between different imaging modalities. The aim of this study was to investigate the level of agreement between the three radiological modalities, computed tomography (CT), magnetic resonance imaging (MRI), and digital radiography (DR), in assessing the ossification of the epiphyses of the knee. A total of 34 deceased individuals of 10-25 years of age, brought in for a medicolegal autopsy at our department, were scanned by CT, MRI, and DR. The ossification stages of the three bones of the right knee, distal femoral, proximal tibial, and proximal fibular epiphysis were assessed using the established combined staging method by Schmeling et al. and Kellinghaus et al. Analysis of the results by Cohen's weighted kappa showed a good agreement between CT and DR (K = 0.61-0.70), and MRI and DR (K = 0.68-0.79) but only moderate agreement between CT and MRI (K = 0.55-0.57). This leads us to conclude that different radiological images cannot be used interchangeably for age estimation purposes, so reference material needs to be imaging-modality specific. However, to make a more general conclusion research on a larger population is needed.

Age assessment in unaccompanied minors: assessing uniformity of protocols across Europe.

Age assessment of migrants is crucial, particularly for unaccompanied foreign minors, a population facing legal, social, and humanitarian challenges. Despite existing guidelines, there is no unified protocol in Europe for age assessment.The Forensic Anthropology Society of Europe (FASE) conducted a comprehensive questionnaire to understand age estimation practices in Europe. The questionnaire had sections focusing on the professional background of respondents, annual assessment numbers, requesting parties and reasons, types of examinations conducted (e.g., physical, radiological), followed protocols, age estimation methods, and questions on how age estimates are reported.The questionnaire's findings reveal extensive engagement of the forensic community in age assessment in the living, emphasizing multidisciplinary approaches. However, there seems to be an incomplete appreciation of AGFAD guidelines. Commonalities exist in examination methodologies and imaging tests. However, discrepancies emerged among respondents regarding sexual maturity assessment and reporting assessment results. Given the increasing importance of age assessment, especially for migrant child protection, the study stresses the need for a unified protocol across European countries. This can only be achieved if EU Member States wholeheartedly embrace the fundamental principles outlined in EU Directives and conduct medical age assessments aligned with recognized standards such as the AGFAD guidelines.

A Virtual, 3D Multimodal Approach to Victim and Crime Scene Reconstruction.

In the last two decades, forensic pathology and crime scene investigations have seen a rapid increase in examination tools due to the implementation of several imaging techniques, e.g., CT and MR scanning, surface scanning and photogrammetry. These tools encompass relatively simple visualization tools to powerful instruments for performing virtual 3D crime scene reconstructions. A multi-modality and multiscale approach to a crime scene, where 3D models of victims and the crime scene are combined, offers several advantages. A permanent documentation of all evidence in a single 3D environment can be used during the investigation phases (e.g., for testing hypotheses) or during the court procedures (e.g., to visualize the scene and the victim in a more intuitive manner). Advanced computational approaches to understand what might have happened during a crime can also be applied by, e.g., performing a virtual animation of the victim in the actual context, which can provide important information about possible dynamics during the event. Here, we present an overview of the different techniques and modalities used in forensic pathology in conjunction with crime scene investigations. Based on our experiences, the advantages and challenges of an image-based multi-modality approach will be discussed, including how their use may introduce new visualization modalities in court, e.g., virtual reality (VR) and 3D printing. Finally, considerations about future directions in research will be mentioned.

Using SXRF and LA-ICP-TOFMS to Explore Evidence of Treatment and Physiological Responses to Leprosy in Medieval Denmark.

Leprosy can lead to blood depletion in Zn, Ca, Mg, and Fe and blood enrichment in Cu. In late medieval Europe, minerals were used to treat leprosy. Here, physiological responses to leprosy and possible evidence of treatment are investigated in enamel, dentine, and cementum of leprosy sufferers from medieval Denmark (n = 12) and early 20th century Romania (n = 2). Using SXRF and LA-ICP-TOFMS, 12 elements were mapped in 15 tooth thin sections, and the statistical covariation of paired elements was computed to assess their biological relevance. The results show marked covariations in the Zn, Ca, and Mg distributions, which are compatible with clinical studies but cannot be directly attributed to leprosy. Minerals used historically as a treatment for leprosy show no detectable intake (As, Hg) or a diffuse distribution (Pb) related to daily ingestion. Intense Pb enrichments indicate acute incorporations of Pb, potentially through the administration of Pb-enriched medication or the mobilization of Pb from bone stores to the bloodstream during intense physiological stress related to leprosy. However, comparisons with a healthy control group are needed to ascertain these interpretations. The positive correlations and the patterns observed between Pb and essential elements may indicate underlying pathophysiological conditions, demonstrating the potential of SXRF and LA-ICP-TOFMS for paleopathological investigations.

How 3D printing and physical reconstruction of a skull helped in a complex pathological case.

Taphonomic changes can mimic pathological bone lesions and make it difficult to distinguish between ante- and postmortem abnormalities and to perform differential diagnostics. 3D methods, such as CT scanning and 3D printing, can be used as complementary tools to overcome the taphonomic changes. Here, we reconstructed a skull of an interesting archeological case showing severe pathological changes using 3D printing and physical reconstruction. The skeleton belonged to an approximately 18-year-old female. The bones of the entire skeleton exhibited several pathological changes. Both cranium and mandible were asymmetric, with a malformed foramen magnum and left zygomatic process, agenesis of the left external acoustic meatus, cribra orbitalia, and a bilateral absence of mental foramen. The overall diagnostic interpretation was hampered by the extensive taphonomic damage that affected the left side of the skull. In particular, the frontal bone showed taphonomic breakage and plastic deformations were present on the left side of the cranium. The skull was CT-scanned and 3D models of all the single bones were 3D printed and manually re-assembled. The intact reconstructed skull was used to estimate the endocranial volume (ECV). We showed how 3D printing and physical reconstruction of the skull helped overcome the extensive taphonomic alterations; the reconstructed skull provides important diagnostic information such as ECV and a better picture of the original ante-mortem pathological state of the skull.

The legal impact of forensic medical life-threatening danger assessment conclusions in cases of violent offense.

OBJECTIVE: The aim of this study was to examine the association between the legal outcome for suspected perpetrators and the forensic life-threatening danger assessments conducted as part of the clinical forensic medical examinations of victims with penetrating injuries. METHOD: From the Danish Central Crime Register, we retrieved the legal outcomes for suspected perpetrators linked to victims with penetrating injuries in a six-year period and compared the proportional distribution of forensic life-threatening danger assessment conclusions - no life-threatening danger (NLD), could have been in life-threatening danger (CLD), and life-threatening danger (LD) - with the legal outcomes. RESULTS: 326 victims were related to at least one identified suspected perpetrator with a legal outcome. When the forensic life-threatening danger assessments were more severe, an increased proportion of cases resulted in formal charges and, subsequently, conviction, than when the forensic life-threatening danger assessments were less severe. The percentage point differences between NLD, CLD, and LD were almost equal. CONCLUSION: Our results indicate that the forensic life-threatening danger assessments are associated with the legal outcome, as both the proportion of cases with formal charges and the proportion of cases with a conviction increased with the severity of the forensic life-threatening danger assessment conclusions.

Technical Note: The Forensic Anthropology Society of Europe (FASE) Map of Identified Osteological Collections.

Identified (documented) osteological collections represent an important resource in the development of forensic anthropology standards and methods as well as a precious tool for learning and training of practitioners. Even though the number of papers presenting identified collections worldwide increases, many of the collections have still not been divulged to the scientific community in sufficient detail to ascertain their exact number. The Forensic Anthropology Society of Europe (FASE) therefore developed a tool that goes beyond sporadic publications: the FASE Map of Identified Osteological Collections, which is freely accessible and continuously updated and revised. The online map is available at http://forensicanthropology.eu/osteological-collections/. The map of skeletal collections was created in 2017 and currently displays information on 153 identified osteological collections (43 of them categorized as contemporary) located in 41 different countries. This article offers a short analysis of the type, geographical location and content of the collections included in the map. The aim of this article and the map as such is to provide a useful resource to facilitate research planning and teaching in forensic anthropology and related disciplines.

Leprosy in medieval Denmark: Exploring life histories through a multi-tissue and multi-isotopic approach.

OBJECTIVES: By focusing on two Danish leprosaria (Naestved and Odense; 13th-16th c. CE) and using diet and origin as proxies, we follow a multi-isotopic approach to reconstruct life histories of patients and investigate how leprosy affected both institutionalized individuals and the medieval Danish community as a whole. MATERIALS AND METHODS: We combine archaeology, historical sources, biological anthropology, isotopic analyses (δ13 C, δ15 N, δ34 S, 87 Sr/86 Sr) and radiocarbon dating, and further analyze bones with different turnover rates (ribs and long bones). RESULTS: The δ13 C, δ15 N and δ34 S results indicate a C3 terrestrial diet with small contributions of marine protein for leprosy patients and individuals from other medieval Danish sites. A similar diet is seen through time, between males and females, and patients with and without changes on facial bones. The isotopic comparison between ribs and long bones reveals no significant dietary change. The δ34 S and 87 Sr/86 Sr results suggest that patients were local to the regions of the leprosaria. Moreover, the radiocarbon dates show a mere 50% agreement with the arm position dating method used in Denmark. CONCLUSIONS: A local origin for the leprosy patients is in line with historical evidence, unlike the small dietary contribution of marine protein. Although only 10% of the analyzed individuals have rib/long bone offsets that undoubtedly show a dietary shift, the data appear to reveal a pattern for 25 individuals (out of 50), with elevated δ13 C and/or δ15 N values in the ribs compared to the long bones, which points toward a communal type of diet and reveals organizational aspects of the institution.

Life-threatening danger assessments of penetrating injuries in Eastern Danish clinical forensic medicine.

Clinical forensic assessments of injuries' life-threatening danger may have an impact on the legal aftermath following a violent assault. The pursuit of evidence-based guidelines should ensure a user-independent and reproducible forensic practice. However, does it? The aim of this study was to evaluate the forensic life-threatening danger assessments after a protocol implementation in 2016. The evaluation concerned usability and reproducibility of the protocol, and its influence on assessment severity. We analyzed the level of inter- and intra-rater agreement using 169 blinded, prior-protocol cases that were reassessed by two forensic specialists. We compared assessment made the year before and after protocol implementation (n = 262), and the forensic specialists' reassessments with the prior-protocol cases' original assessments (n = 169). Whether to make an assessment, the levels of agreement varied between weak agreement (inter-rater, Κ = 0.43; assessor 1, Κ = 0.57) and strong agreement (assessor 2, Κ = 0.90). Regarding severity, the levels of agreement varied between strong agreement (inter-rater, Κ = 0.87; assessor 1: Κ = 0.90) and almost perfect agreement (assessor 2: Κ = 0.94). The assessments were statistically significant redistributed after the implementation (chi-square test: p < 0.0001). The proportion of cases assessed as having not been in life-threatening danger increased from 9 to 43%, and moderate severity assessments decreased from 55 to 23%. Of the moderate severity assessments, 55% were reassessed as having not been in life-threatening danger. The protocol ensured independent and reproducible assessments when the forensic specialists agreed on making one. The protocol resulted in less severe assessments. Future studies should examine the reliability of the protocol and its consequences for legal aftermaths.

The usefulness of a trauma probability of survival model for forensic life-threatening danger assessments.

Clinical forensic medical examinations constitute an increasing proportion of our institution's tasks, and, concomitantly, the authorities are now requesting forensic life-threatening danger assessments based on our examinations. The aim of this retrospective study was to assess if a probability of survival (PS) trauma score could be useful for these forensic life-threatening danger assessments and to identify a cut-off PS score as a supporting tool for the forensic practice of assessing life-threatening danger. We compared a forensic database and a trauma database and identified 161 individuals (aged 15 years or older) who had both a forensic life-threatening danger assessment and a PS score. The life-threatening danger assessments comprised the following statements: was not in life-threatening danger (NLD); could have been in life-threatening danger (CLD); or was in life-threatening danger (LD). The inclusion period was 2012-2016. A statistically significant difference was found in the PS scores between NLD, CLD and LD (chi-square test: p < 0.0001). The usefulness of the PS score for categorizing life-threatening danger assessments was determined by a receiver-operator characteristic (ROC) curve. The area under the curve was 0.76 (95% CI, 0.69 to 0.84) and the ROC curve revealed that a cut-off PS score of 95.8 would appropriately identify LD. Therefore, a PS score below 95.8 would indicate life-threatening danger. We propose a further exploration of how the evidence-based PS score, including a cut-off value, might be implemented in clinical forensic medical statements to add to the scientific strength of these statements.

Strengthening the role of forensic anthropology in personal identification: Position statement by the Board of the Forensic Anthropology Society of Europe (FASE).

In this position statement, the Board members of the Forensic Anthropology Society of Europe (FASE) argue that forensic anthropology methods can be used as means of personal identification, particularly in situations with limited availability of traditional identification methods (i.e. dactyloscopy, odontology, and molecular genetic analysis). This statement has been issued taking into account the international migration crises related to thousands of deaths worldwide, in which the utility of these traditional means of identification has been sporadic to non-existent. The statement is however not limited to deaths related to the migration crises, as similar problems may occur in fatalities en masse such as in natural disasters and armed conflicts, and on a smaller scale in cases of homeless or otherwise socioeconomically disadvantaged persons. The number of reports on personal identification based on sound anthropological methodology is increasing in the scientific literature. However, more research is needed to develop evidence-based standard operating procedures and statistical frameworks. It remains essential to raise awareness among forensic practitioners, law enforcement, and judiciary professionals on the utility of forensic anthropology in cases where it can provide sufficient information for identification.

Screening archaeological bone for palaeogenetic and palaeoproteomic studies.

The recovery and analysis of ancient DNA and protein from archaeological bone is time-consuming and expensive to carry out, while it involves the partial or complete destruction of valuable or rare specimens. The fields of palaeogenetic and palaeoproteomic research would benefit greatly from techniques that can assess the molecular quality prior to sampling. To be relevant, such screening methods should be effective, minimally-destructive, and rapid. This study reports results based on spectroscopic (Fourier-transform infrared spectroscopy in attenuated total reflectance [FTIR-ATR]; n = 266), palaeoproteomic (collagen content; n = 226), and palaeogenetic (endogenous DNA content; n = 88) techniques. We establish thresholds for three different FTIR indices, a) the infrared splitting factor [IRSF] that assesses relative changes in bioapatite crystals' size and homogeneity; b) the carbonate-to-phosphate [C/P] ratio as a relative measure of carbonate content in bioapatite crystals; and c) the amide-to-phosphate ratio [Am/P] for assessing the relative organic content preserved in bone. These thresholds are both extremely reliable and easy to apply for the successful and rapid distinction between well- and poorly-preserved specimens. This is a milestone for choosing appropriate samples prior to genomic and collagen analyses, with important implications for biomolecular archaeology and palaeontology.

Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause.

Keel bone fractures in laying hens have been described with increasing prevalence from several countries over the last twenty years and are considered one of the greatest welfare problems to the layer industry. In Denmark we have observed fracture prevalence in the range of 53% to 100% in flocks from cage-free systems whereas flock prevalences in birds from enriched cages ranged between 50-98%. Previous research have speculated that the underlying reason for the development of keel bone fractures is trauma in relation to impact of the bird with furniture, other equipment etc. However, little evidence of this theory has been provided. Predisposing factors have also been suggested including genetics of the bird, lack of specific feedstuff components, high egg production, management factors and layer fatigue. This study has addressed the possible pathogenesis of these fractures by pathological characterization of fractures in birds from different production systems. More than 60 keel bones with fractures have been characterized histo-pathologically and by CT scan. This included an assessment of damage to muscles and soft tissues, the bone and the healing process including callus formation. This investigation has shown that high energy collisions cannot be responsible for the majority of fractures, located at the caudal tip of the keel bone, observed in laying birds as markers associated trauma were not observed in the majority of the cases just as few recognized healing processes were observed. These results suggest an alternative pathogenesis to trauma.

Odontological identification dental charts based upon postmortem computed tomography compared to dental charts based upon postmortem clinical examinations.

Since the beginning of this century, the use of postmortem computed tomography (PMCT) in forensic autopsies has increased. In this study we examined how similar dental charts created using PMCT as a solitary examination mode were to dental charts created using the conventional method of a clinical inspection including intraoral radiographs. A total of 100 previously performed dental identification cases were retrospectively included in the study. For each case, a dental chart was created solely based upon PMCT. The PMCT based dental chart was subsequently compared with the chart created from the previous conventional identification examination. Based upon the accuracy, sensitivity and specificity values PMCT performed very well compared to the conventional method in the identification concerning presence or absence of teeth, the presence of crowns, bridges and endodontic treatments as well as the presence and types of fillings. PMCT performed poorly concerning the extension of fillings and identification of small, tooth-colored fillings. The use of PMCT is a valuable supplement to the conventional methods available for forensic odontologists and may be of great value for initial screening in mass fatalities.

Transition analysis applied to third molar development in a Danish population.

INTRODUCTION: Age assessment based on dental development is often requested in order to assess whether an individual is older or younger than 18 years of age. There are several statistical approaches to estimate age based upon third molar development. The aim of this study was to apply the principles of transition analysis (TA) to a Danish reference material and to evaluate whether it was indicated to include a model that allows for logistic non-linearity as opposed to applying a model only allowing for logistic linearity. For this we chose to use the generalized additive model (gam) and the generalized linear model (glm), respectively. MATERIAL AND METHOD: A cross-sectional sample comprising 1302 panoramic radiographs of Danish subjects in the chronological age range of 13-25 years was included. All present third molars had been scored according to the 10-stage method of Gleiser and Hunt. Each transition from one stage to the subsequent stage was analyzed according to the statistical approach of TA and fitted with both the generalized linear model (glm) and the generalized additive model (gam). In order to assess whether gam or glm was more parsimonious for each transition individually, the Akaikon information criterion (AIC) was applied. RESULTS: The results emphasized the importance of applying a statistical model that sufficiently captures the spread of the age estimate. The AIC values showed that some transitions were sufficiently described by glm whereas for others the gam curves fitted significantly better. CONCLUSION: We recommend that for an age assessment tool based on TA, both a fitting allowing for non-linearity and one allowing only for linearity should be included.

Enlargement of the human adrenal zona fasciculata and chronic psychiatric illness - an autopsy-based study.

Severe mental illness (SMI) is associated with a reduced life expectancy of up to 20 years. One possible contributor to this fact is dysregulation of the hypothalamus-pituitary-adrenal (HPA)-axis. Looking at the morphology of effector organs, such as the adrenal glands themselves, could reveal insights into organ function and response to possible HPA-dysregulation. This forensic autopsy-based study investigated if there were any morphological changes in adrenal glands between decedents who had previously been submitted to a psychiatric hospital with a diagnosis of schizophrenia (n = 34), bipolar (n = 5), or depressive disorder (n = 20), any other psychiatric diagnosis (n = 36) compared with decedents who had no previous psychiatric admission (n = 40). Length of admissions to psychiatric wards and admission in the 180 days preceding death was included in regression as proxy variables for severity of illness. On the macroscopic level, we found no difference in gland weight or volume. On the microscopic level, we found a 25% increase in cross-sectional area of the zona fasciculata (ZF) in decedents who had a diagnosis of schizophrenia compared with controls (p = 0.033). Other diagnosis groups did not differ from controls. Total admission length was positively correlated with area of the ZF.Lay SummaryPeople with a severe mental disorder may be in a constant state of increased stress, which is harmful. This study looked at the adrenal gland, which produces stress hormones, to see if they were different in deceased persons who had suffered from a severe mental illness. We found that the part of the adrenal gland that produces stress hormones is larger in deceased patients who suffered from schizophrenia, but not other types of psychiatric illnesses, compared to deceased persons with no history of psychiatric illness.

Comparison of hippocampal volume measurement by autopsy and post-mortem magnetic resonance imaging.

We present an autopsy-validated, non-invasive, magnetic resonance imaging (MRI) based segmentation algorithm, for determining hippocampal volume. A segmentation algorithm was developed to assess the volume of the hippocampus. Deceased individuals with severe mental illness were used to evaluate the use of MRI imaging to determine hippocampal volume as this group has previously been associated with altered hippocampal volume diagnosed on MRI. The accuracy of the MR- scanning protocol for volume measurement was tested on a water filled phantom control with a known volume of 500 ml, and a difference of 0.08% was found. Thus the scanning protocol was deemed to have produced acceptable results when comparing volume measures of a pair of segmented hippocampi obtained at the 1 T MR scanner and a 3 T MR scanner using the software program Mimics®. The segmentation algorithm was tested by a volume comparison obtained using anterior and posterior landmarks (in situ) and the exact volume of the dissected hippocampus (ex situ). The in situ and ex situ hippocampal volumes were highly correlated; R2 was 96%, with a mean difference of 4-5%. Cases were also examined for intra- and inter-observer agreement. This study presents a validated segmentation algorithm that can be used to determine the hippocampal volume using post-mortem MR and anatomical landmarks.

Temporal changes in childhood health during the medieval Little Ice Age in Denmark.

OBJECTIVE: This study examines the evidence of three skeletal markers of childhood health that leave permanent observable changes in the adult skeleton during two climate events, the Medieval Warm Period (MWP) and the Little Ice Age (LIA) that occurred in the medieval period (1050-1536 CE). MATERIAL: A total of 241 adult skeletons from the Danish medieval period were included. METHODS: Linear enamel hypoplasia (LEH) was examined macroscopically. Harris lines (HL) and infectious middle ear disease (IMED) were examined from CT imaging. The skeletons were segregated by the mortuary pattern of arm position that coincidentally changes between the MWP to the LIA. RESULTS: LEH and IMED increase in frequency from the MWP to the LIA while there is a reverse trend for HL. SIGNIFICANCE: This is the first study that examines childhood health as reflected on skeletal remains of adults using a combination of CT imaging and macroscopic examination for temporal changes in the medieval period. LIMITATIONS: The study did not include any sub-adults due to limitation of methods, i.e. the method of IMED is not yet developed to assess sub-adults. Neither was time-of-occurrence for the skeletal marker included as there is conflicting information from different methods for HL and neither has it been developed yet for IMED. SUGGESTIONS FOR FURTHER RESEARCH: A sample of sub-adults from both time periods could be compared by sub-adult mortality, as well as for differences in the timing of skeletal age markers.

Post-mortem computed tomography as part of dental identification - a proposed guideline.

PURPOSE: This paper presents a proposed guideline for the use of post-mortem computed tomography (PMCT) during forensic dental identification. Currently, whole-body PMCT is widely used prior to autopsies for the diagnosis of fractures, organ changes, hemorrhages, and for the localization of foreign bodies, but it may also facilitate the odontological identification process in single cases and in cases involving multiple fatalities. Several studies have described the use of PMCT in forensic odontological work, but we have not found any comprehensive set of guidelines on how to perform a forensic odontological examination using PMCT. The aim was to develop guidelines for creating post-mortem dental charts during forensic odontological identification examinations using the standard functions of PMCT. METHODS: A proposed guideline was developed from 15 selected cases examined at the Section of Forensic Pathology, Department of Forensic Medicine at the University of Copenhagen in Denmark from October 2011 to May 2012. Using the functionalities and three-dimensional (3D) reconstructions of OsiriX DICOM-viewer software (Pixmeo Sarl, Bernex, Geneva, Switzerland) we adjusted the contrast and brightness settings and developed a proposed guideline for creating PMCT-based dental charts. A four-step guideline was produced. CONCLUSION: In our casework, we are currently using the guidelines proposed herein. The use of PMCT has allowed us to target our clinical examinations, greatly improving their efficiency. Furthermore, PMCT allows the storage of data for later documentation and research. Further research is needed to validate the proposed guideline.