Human coxal bone sexual dimorphism and multislice computed tomography: geometric morphometric analysis of 65 adults

The authors studied sexually dimorphic differences in coxal shape using geometric morphometric analysis of 15 osteometric landmarks recorded by multislice computed tomography (MSCT), based on three-dimensional reconstructions of 65 Caucasian adults. Geometric morphometric analysis, principal component analysis, canonical variates analysis, and other discriminant analysis (Goodall's F-test and Mahalanobis distance) were performed for the three separate bones of the left innominate (pubis, ilium, and ischium), the modified pubis (pubis and ischiopubic ramus), the modified ilium (ilium and ischial spine), three bone complexes (ischiopubic, iliopubic, and ilio-ischial), and the complete innominate. A cross-validation test was also performed. All areas studied were dimorphic, but results for sexual dimorphism in decreasing order were as follows: the modified pubis, followed by the ischiopubic complex, the iliopubic complex and the complete innominate, the pubis, the modified ilium, the ilio-ischial complex, the ilium, and finally the ischium. These results show the potential of this approach for future anthropological research.     

Massive systemic fat embolism detected by postmortem imaging and biopsy*

Postmortem computed tomography (pmCT) and pmCT angiography (pmCTA) provide a minimally invasive method to determine the cause of death. Postmortem image-guided biopsy allows for precise sampling of histological specimens. This case study describes the findings of lethal systemic fat embolism (FE) on whole-body unenhanced pmCT, pmCTA, and image-guided biopsy, with autopsy and histopathologic correlation. Unenhanced pmCT revealed a distinct fat level on top of sedimented layers of corpuscular blood particles and serum in the arterial system and pulmonary trunk. Subsequent pmCTA showed reproducible results, and image-guided biopsy confirmed fatal FE. pm CT/pmCTA combined with image-guided biopsy established the cause of death as right heart failure as a result of systemic fatal FE prior to autopsy. All imaging findings were consistent with traditional autopsy and histological specimens. This unique case demonstrates new imaging findings in massive, fatal FE and highlights that postmortem imaging, supplemented by image-guided biopsy, may detect the cause of death prior to traditional autopsy.     

Anatomical Placement of the Human Eyeball in the Orbit-Validation Using CT Scans of Living Adults and Prediction for Facial Approximation*

Abstract: Accuracy of forensic facial approximation and superimposition techniques relies on the knowledge of anatomical correlations between soft and hard tissues. Recent studies by Stephan and collaborators (6,8,10) reviewed traditional guidelines leading to a wrong placement of the eyeball in the orbit. As those statements are based on a small cadaver sample, we propose a validation of these findings on a large database (n = 375) of living people. Computed tomography scans of known age and sex subjects were used to collect landmarks on three‐dimensional surfaces and DICOM with TIVMI. Results confirmed a more superior and lateral position of the eyeball relatively to the orbital rims. Orbital height and breadth were used to compute regression formulae and proportional placement using percentages to find the most probable position of the eyeball in the orbit. A size‐related sexual dimorphism was present but did not impact on the prediction accuracy.     

Correlation between skeletal trauma and energy in falls from great height detected by post-mortem multislice computed tomography (MSCT)

Fatal falls from great height are a frequently encountered setting in forensic pathology. They present – by virtue of a calculable energy transmission to the body – an ideal model for the assessment of the effects of blunt trauma to a human body.As multislice computed tomography (MSCT) has proven not only to be invaluable in clinical examinations, but also to be a viable tool in post-mortem imaging, especially in the field of osseous injuries, we performed a MSCT scan on 20 victims of falls from great height. We hereby detected fractures and their distributions were compared with the impact energy.Our study suggests a marked increase of extensive damage to different body regions at about 20 kJ and more. The thorax was most often affected, regardless of the amount of impacting energy and the primary impact site. Cranial fracture frequency displayed a biphasic distribution with regard to the impacting energy; they were more frequent in energies of less than 10, and more than 20 kJ, but rarer in the intermediate energy group, namely that of 10–20 kJ.     

Postmortem Computed Tomography Findings of Upper Airway Obstruction by Food

Abstract: This study is a retrospective analysis of 14 cases with food bolus upper airway obstruction as the defined cause of death where both postmortem computed tomography and autopsy were performed. Three groups were defined by the images i.e., Type 1: foreign body situated between the oral cavity and oropharynx, while the epiglottis sits in normal position, Type 2: foreign body situated in the oropharynx just above the epiglottis pushing it posteriorly and obstructing the airway, and Type 3: foreign body obstructing the laryngeal inlet while pushing the epiglottis anteriorly. At the time of autopsy, foreign bodies were detected by pathologists, occasionally in a different position, presumably being dislodged in the act of organ removal especially for the “Type 1” pattern. CT imaging provides accurate interrogation of upper airway bolus obstruction prior to autopsy.     

Application of Postmortem 3D‐CT Facial Reconstruction for Personal Identification*

Abstract: Postmortem computed tomography (CT) images can show internal findings related to the cause of death, and it can be a useful method for forensic diagnosis. In this study, we scanned a ready‐made box by helical CT on 2‐mm slices in a mobile CT scanner and measured each side of the box to assess whether reconstructed images are useful for superimposition. The mean difference between the actual measurements and the measurements on the three‐dimensional (3D) reconstructed images (3D‐CT images) is 0.9 mm; we regarded it as having no effect on reconstruction for the superimposition method. Furthermore, we could get 3D‐CT images of the skull, which were consistent with the actual skull, indicating that CT images can be applied to superimposition for identification. This study suggested that postmortem CT images can be applied as superimpositions for unidentified cases, and thinner slices or cone beam CT can be a more precise tool.     

二分髌骨影像学征象及其法医学意义

二分髌骨较罕见,系因青春期二个或多个髌骨骨化中心(化骨核)未融合而形成,临床误诊为骨折的屡有报道。为提高对二分髌骨影像征象的认识,避免法医学鉴定失误,现分析行法医学鉴定的3例二分髌骨资料并结合文献,阐述其形成原因、组织学变化、影像学征象及临床症状体征。3例被鉴定人均为成年,因膝关节外伤后出现膝部疼痛,曾被医疗单位诊断为髌骨骨折,委托损伤鉴定2例,伤残评定1例。依据Saupe’s分型法,其中Ⅲ型2例,Ⅱ型加Ⅲ型1例。在法医学鉴定实践中,熟知二分髌骨影像学征象并与髌骨骨折鉴别,可确保鉴定结论的客观、准确。     

Forensic Age Estimation Using Thin‐Slice Multidetector CT of the Clavicular Epiphyses Among Adolescent Western Chinese

Reaching the age of 18 years is the most significant step for criminal proceedings in China. In this study, a population of 752 individuals was recruited to clarify how strong the chronological age relates to clavicular ossification status revealed by CT scans with 1 mm slice thickness in the West China Han population. Finally, the epiphysis was observed to commence fusion in females at 16.28 years and 16.74 years in males and be fully ossified by 25.97 years in females and 25.81 years in males. These findings suggested that ossification of medial clavicular epiphyseal cartilage can be used in age estimation for West China Han population with the age threshold of 18 years. By comparison with previous German studies, our results suggested that the pace of ossification of medial clavicular epiphyseal cartilage may be potentially affected by socioeconomic status.     

Metric Sex Determination of the Human Coxal Bone on a Virtual Sample using Decision Trees

Decision trees provide an alternative to multivariate discriminant analysis, which is still the most commonly used in anthropometric studies. Our study analyzed the metric characterization of a recent virtual sample of 113 coxal bones using decision trees for sex determination. From 17 osteometric type I landmarks, a dataset was built with five classic distances traditionally reported in the literature and six new distances selected using the two-step ratio method. A ten-fold cross-validation was performed, and a decision tree was established on two subsamples (training and test sets). The decision tree established on the training set included three nodes and its application to the test set correctly classified 92% of individuals. This percentage was similar to the data of the literature. The usefulness of decision trees has been demonstrated in numerous fields. They have been already used in sex determination, body mass prediction, and ancestry estimation. This study shows another use of decision trees enabling simple and accurate sex determination.     

死后尸体CT在法医学鉴定中的应用价值初探

目的 对不同类型案件中的死者进行死后尸体CT扫描和常规尸体解剖,探索PMCT在法医学鉴定中的应用价值.方法 对7例因不同原因死亡的个体进行全身PMCT扫描,随后进行系统的尸体解剖,通过比较两种方法检测的结果,分析PMCT与传统尸体解剖在不同类型案件中应用的优点和不足.结果 在7个案例中,尸体上总共检出67处阳性发现.其...