International Journal of Legal Medicine最新文献

In forensic practice, the removal of soft tissue is sometimes required to allow for a more accurate skeletal analysis. One of the preferred skeletal processing methods is maceration, the softening of tissue by soaking in water. Despite being widely mentioned in forensic literature, there is still a lack of comprehensive data on how and which maceration methods are applied in daily forensic practice, especially as maceration can be carried out by different forensic professionals and in diverse forensic settings. The aim of this study was to review the published literature on forensic use of maceration and conduct an international survey to compare the practices used with those described in the literature, with special attention on the effects on tool marks and material traces analyses on bone. The literature review, conducted on 27 articles that met the study's inclusion criteria, showed that maceration has been a topic of research and methodological development over the years. Warm water maceration and detergent-based methods were recognized as preferred for practical use, even though no maceration method is without limitations. Survey responses from 57 laboratories and institutes from 19 different countries indicated that while most used methods align with literature recommendations, some practices considered aggressive remain in use. Additionally, it was observed that there is a significant lack of standardization, and maceration is often not included in standard operating procedures (SOPs), which can affect the consistency, efficiency and reproducibility of the methods used, which is something that should be addressed in future.

Utilizing the Finite Element Method and the Total HUman Model for Safety model, simulations were conducted of adult subjects landing with both feet on a hard surface from various heights. The biomechanical response was deconstructed using stress analysis, binary logistic regression, and hierarchical clustering based on Jaccard distance. The simulations revealed a stress propagation mechanism and a longitudinal axial distribution of stress concentrations. Fracture risk exhibited two distinct modes: a "stepwise response" in primary load-bearers (e.g., feet, spine) and a "graded response" in secondary structures (e.g., fibular ends). Logistic regression quantified the height-dependent fracture risk for the fibular ends (OR = 1.682), skull (OR = 1.576), and pelvis (OR = 1.236). The hierarchical cluster analysis of injury patterns corresponds to distinct biomechanical phases: the localized injury phase involving local dissipation, the stress propagation phase characterized by axial transmission, and the systemic injury phase marked by comprehensive damage. This study establishes a comprehensive "mechanism-risk-pattern" biomechanical framework that effectively explains the progression of skeletal trauma during falls. This framework provides a powerful tool for hypothesis generation in forensic case analysis. Extensive experimental findings indicate that threshold settings influence model outcomes, making direct quantitative application to case evidence inadvisable before model optimization. The core contribution of this study lies in proposing this interpretive paradigm, which reveals the systemic nature of skeletal injury and provides a structured pathway for deciphering complex trauma.

Forensic entomologists estimate minimum post-mortem intervals (PMI_min) by measuring the development of larvae on decomposing bodies. Entomotoxicology assumes significance when the deceased had ingested drugs, as these may alter insect development and consequently the accuracy of PMI_min estimations. 5F-ADB, ADB-BUTINACA, and MDMB-4en-PINACA are potent synthetic cannabinoid receptor agonists and drugs of abuse, linked to human intoxications and deaths. We investigated the impact of 5F-ADB on the development of Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae) larvae and developed a method to detect 5F-ADB, ADB-BUTINACA, MDMB-4en-PINACA, and their metabolites in larvae by liquid chromatography-mass spectrometry. Neonate larvae were exposed to 5F-ADB concentrations that reflect those in human post-mortem specimens. At precise intervals, larvae were killed in near-boiling water, dried, and then their size measured, followed by toxicological analysis. ANOVA demonstrated that only time (= age) significantly affected larval length and mass (through growth). Drug concentrations typically found in post-mortem peripheral blood did not significantly affect larval development, suggesting that 5F-ADB in a corpse would not influence PMI_min estimation with L. sericata. 5F-ADB was detected in trace amounts in larvae that were exposed to post-mortem peripheral blood concentrations. Most larvae from higher concentration treatments contained 5F-ADB levels above the limit of detection of 0.25 µg/kg, but not all samples tested positive. Post-feeding larvae mostly did not contain detectable levels of 5F-ADB, and metabolites were found in none of the larval samples. Actively feeding L. sericata larvae from a corpse may thus be useful to qualitatively identify a prior consumption of 5F-ADB by the deceased.

Objectives: Examination of the radius' distal epiphysis by means of low-field MRI in order to find a reliable method to correctly assess majority in both sexes.

Materials & methods: 650 volunteers of German nationality, evenly distributed to groups of 25 per sex and years of proven age in the age bracket of 12-24 years, were examined between 2021 and 2023 in a single center, prospective, cross-sectional setting. A 0.31 T dedicated joint scanner was used, acquiring a proton density-weighted (PDw) sequence in Dixon technique (Dixon) in coronal slice orientation yielding a fat-sensitive water-suppressed (fat-only) and a water-sensitive fat-suppressed (water-only) series. A classification was formulated for assessment and tested against the proven age. The relevant statistics were defined, the intra- and interobserver-agreements were determined, and the differences between the sexes were analyzed.

Results: The minimum age for stage 6 of the classification was found to be 18.42 years in male individuals and 17.25 years in female individuals. A Mann-Whitney-U Test implies significant sex-related differences for stage 3 (p < 0.01) and stage 4 (p < 0.01), but not for stage 2 (p < 0.162), stage 5 (p < 0.193) and stage 6 (p < 0.146). The intra- and interobserver-agreement levels were substantial.

Conclusion: When using the presented setting of a low-field 0.31 T dedicated joint scanner, acquiring PDw Dixon fat-only and water-only series of the radius' distal epiphysis and using the presented classification, majority can be determined in male but not in female individuals of our cohort. Therefore, 0.31 T low-field MRI yields similar opportunities as examinations by means of high-field MRI scanners.

This case report describes a homicide in which the victim sustained fatal blunt force trauma to the head caused by an initially unidentified weapon. In addition to soft tissue injuries to the scalp, the victim also suffered a single depressed fracture on the central calvaria located at the os frontale. During the forensic medical examination, the cause of death was determined to be a combination of exsanguination and craniocerebral trauma. However, it was not possible to clearly identify the weapon used based on the soft tissue and bone injuries. Histological analysis revealed foreign material containing iron within the wounds. In the marks examination, the cracks in the fracture of the external plate of the calvaria were compared with potential tools of the crime. Striking similarities were identified regarding the shape and size of the cracks in the bone and scratch marks in the paint coating of a weight plate of a dumbbell that was recovered at the crime scene. Further material analysis confirmed the presence of black, polyester-based coating particles within the bone fractures, chemically identical to the paint coating of the weight plate. These findings led to the identification of the weight plate as the instrument of injury, a conclusion upheld by the court. This case underscores the critical importance of interdisciplinary collaboration within forensic science. Particularly in this case involving blunt force trauma. By integrating forensic medical and histological examination, micro trace analysis and comparative marks examination, the weight plate could successfully be identified as the weapon used.

Y-chromosomal short tandem repeats (Y-STRs) are pivotal tools in forensic science, such as paternity testing, male lineage tracing, and genealogical investigations. However, traditional models, such as the stepwise mutation model (SMM) fail to address more complex mutation mechanisms, such as gene deletion and gene conversion. These limitations hinderthe accuracy of lineage analyses, particularly for multi-copy loci. This study analyzed two types of Y-STR mutation abnormalities through five detailedcases, using STR typing andnext-generation sequencing (NGS) technology. Biological samples from 5 father-son and father-cousin pairs were genotyped withthe Yfiler™ Platinum Kit and the Microreader™ RM-Y ID kit.The STR typing was conducted using the next-generation sequencing STRTyper Y68 Kit. A gene conversion mutation was observed at the multicopy locus DYS385ab in Case 1.The deletion of multicopy loci (DYS527ab, DYS387ab, DYF404S1, DYS464, DYS399S1, DYS626, and DYS448) within the the five male pedigree samples (father-son or uncle-nephew) pairs c region was observed in cases 2-5. This finding highlights the limitations of single-step mutation models (SMM) in analyzing multi-copy Y-STR loci and underscores the necessity of incorporating non-stepwise mutation mechanisms into forensic methodologies.This study advances understanding of Y-STR mutation dynamics, providing significant implications for forensic science and human genetics.

In this case report, sudden cardiac death caused by intussusception of a coronary artery is discussed. A 47-year-old man was found dead in the nursing home where he lived, following an episode of polyphagia and two of vomiting. Upon cadaveric dissection, an overdistention of the large intestine was noted. Re-evaluation of the formalin-fixed whole heart revealed occlusion of the circumflex branch of the left coronary artery, which was not macroscopically attributable to vascular thrombosis or an atheromatous plaque. Histological investigations revealed ischaemic-type histological changes of the left ventricular wall in a hyperacute phase of evolution and, in the occluded coronary branch, extensive intraluminal invagination of the intima and media, as occurs in vascular intussusception. Further stains revealed the presence of fibromuscular dysplasia of the wall of the affected vessel. The subject's death was ascribable to an acute cardiovascular failure secondary to acute ischaemic myocardial injury induced by intussusception of a coronary artery affected by dysplastic degeneration. These findings fully account for death by a mechanism sustained both by a mechanical deficit of the cardiac pump and by the possible onset of arrhythmias. Arterial intussusception is a rare complication of spontaneous coronary artery dissection. It is assumed that a combination of predisposing factors, which weaken the arterial wall, and trigger events, such as Valsalva-like activities, underlie the onset of the latter condition. This case highlights the importance of considering rare causes of sudden cardiac death. Greater awareness of these conditions can contribute to a more accurate identification of causes of death, with significant implications in both forensic and clinical settings.

Electrocution remains a significant cause of workplace fatalities, particularly in high-voltage environments. Diagnostic challenges arise from the often non-specific internal and external autopsy findings, necessitating robust evidence for reconstructing events and determining liability. This report presents a case of fatal high-voltage electrocution at a hydroelectric plant, focusing on the analysis of suspected electrical entry and exit wounds using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). A middle-aged male electrician sustained fatal injuries while working on a 63 kV transformer. Autopsy revealed electrical burns consistent with electrocution. SEM-EDS analysis identified an electrical entry wound on the right hand, characterized by metallization consistent with contact with a conductive object, specifically a metal tape measure found near the body. This finding supports a scenario involving safety protocol violations and human error. Multiple exit wounds were observed, a recognized phenomenon in high-voltage electrocutions. Notably, metallization was confirmed at exit wounds in skin samples from the left hand and feet, a finding typically considered a hallmark of electrical entry wounds. This unexpected observation underscores the importance of analyzing both entry and exit wounds with SEM-EDS to avoid misinterpretations. This case highlights the crucial role of SEM-EDS in the forensic analysis of electrical injuries, facilitating accurate event reconstruction and aiding in liability assessment.

Objectives: This paper presents a metric methodology for estimating biological sex specifically tailored to the Italian population. The method considers 121 standard metric measurements derived from 46 bones across various post-cranial regions.

Materials and methods: The sample consists of 400 individuals (M = 200; F = 200) from the 20th century CAL Milano Cemetery Skeletal Collection aged 20 to 104 years old. The sample was divided into a training subset (75%; n = 300) and a testing subset (25%, n = 100). Intra- and inter-observer analyses, as well as univariate sectioning points, and multivariable logistic regression analyses were performed.

Results: Intra- and inter-observer analysis showed excellent reproducibility of the measurements, with some exceptions generally related to the measurement of long bone diameters. Univariate sectioning points resulted in 18 measurements with accuracies exceeding 90%, and another 48 measurements achieving over 80% accuracy. In total, 43 multivariable logistic regression models were developed for 32 bones, and these models further increased the accuracy.

Discussion: The validation of these models demonstrated that the proposed methodology allows for sex estimation with accuracies of over or near 90% and minimal class discrimination bias across all post-cranial skeletal regions. The highest accuracies - with both sectioning points and multivariable models - were the radius (96.8%), scapula (95.3%), and tibia (95.2%). This study introduces a comprehensive metric standard for the Italian population and highlights the accuracy of the metric approach for estimating biological sex.