Survival of Atherosclerotic Calcifications in Skeletonized Material: Forensic and Pathological Implications

Towards an integrative approach to the biological profile

One of the most important tasks in forensic anthropology is the construction of the biological profile, classically defined as a set of four basic biological descriptors: biological sex, age-at-death, ancestry, and stature. Yet, our empirical and technological abilities in reconstructing the life experiences and health from skeletal remains far exceed these four parameters and forensic anthropology could benefit from further descriptors in the search for an identity. In this paper, we propose the inclusion of two other investigations to forensic anthropology practice to implement the already known biological profile: the interpretation of bone disease and lesions, and forensic toxicology on unconventional biological matrices. These analyses can provide information regarding health, habits, and disease burden, and by implementing them in our practice of forensic anthropology, they have the potential to improve the biological profile. We also propose a new term that can include not only the classical biological profile but also further descriptors, namely, the "biocultural profile".

The Identification Potential of Atherosclerotic Calcifications in the Context of Forensic Anthropology

Atherosclerosis is an inflammatory disease that, in its more developed stages, can lead to the calcification of fatty plaques on the walls of arteries, resulting in the appearance of new bone elements. It is a condition that has been studied and documented little in the context of paleopathology, especially in the framework of forensic anthropology. This article analyzed the skeletal remains of 71 individuals (35 females and 36 males) from the Luís Lopes Identified Collection of the National Museum of Natural History and Science in Lisbon, 31 of whom had an autopsy report. An attempt was made to ascertain whether these bone elements resulting from atherosclerotic calcification would resist cadaveric decomposition and whether they would be recoverable several years after burial, and a survey was carried out of their distribution according to sex and age, as well as their association with other pathologies, such as osteoporosis and cardiac and renal pathologies. An imaging analysis of an atherosclerotic plaque was also carried out to complement the macroscopic analysis and present other methods of identifying plaques. It was concluded that each atherosclerotic calcification has a unique profile, which can be useful for identification, especially in cases where the individual shows a severe condition. In terms of identification potential, the analysis of calcified atherosclerotic plaques can be useful, as they can corroborate or reject an identification. However, it always requires the existence of ante-mortem imaging exams and must always be used in addition to other identification methods. Regardless of the identification, these plaques are bone elements resulting from a pathology and should, therefore, be known and recognized by the scientific community.

An osteometric and 3D analysis of the atlanto-occipital joint: An initial screening method to exclude crania and atlases in commingled remains

OBJECTIVES

The anatomical features of the atlanto-occipital joint can be potentially useful in re-associating or excluding crania to atlases in commingled remains. This study investigated whether linear measurements and the 3-dimensional (3D) surface of occipital condyles and articular facets of atlases can represent valid insights for this purpose.

METHODS

The variations among eight corresponding linear distances were analyzed in a sample of 150 individuals through six supervised machine learning techniques attempting to develop classifiers able to identify elements belonging to the same individual. Furthermore, a 3D analysis was conducted on the articular surfaces through superimpositions of 3D models of corresponding and non-corresponding crania and atlases obtained by using respectively stereophotogrammetry and laser scanning. This analysis investigated differences in terms of point-to-point distances (Root Mean Square, RMS) of superimposed 3D surfaces.

RESULTS

None of the six machine learning techniques were able to correctly detect a satisfying percentage of correspondent pairs in the overall sample by using the linear variables. The 3D analysis of the articular surfaces found RMS values over 0.53 mm only for superimposed non-corresponding surfaces, which sets a threshold value to identify 32% of incorrect pairs.

DISCUSSION

The re-association of cranium to atlas proved to be challenging and hardly possible when considering only metric variables. However, the 3D geometry of the articular surfaces represents a valid variable for this purpose and 3D analyses pave the way for an initial exclusion of incorrect re-associations, thus should not be considered as a re-association method per se, but as an exclusionary screening technique.

Frequency of biological non-skeletal materials in dry bone scenarios

In forensic anthropology, many small biological non-osseous materials may be found associated to skeletonized remains and can provide crucial information to the biological profile. Indeed, their careful recovery and correct identification can add information related to age-at-death, sex, ancestry, health, diet, migration and habits, and may be used in specific analysis such as DNA typing. However, and despite their potential, little is known about these non-osteological materials. Indeed, how frequent are they in dry bone cases? To answer this question, 100 skeletal remains with postmortem intervals ranging from 23 to 76 years from the CAL Milano Cemetery Skeletal Collection were meticulously examined for the presence of non-skeletal materials and in particular ossified cartilage, vascular calcifications, hair and nails. As a result, non-skeletal materials were found in 81 skeletal remains and showed high frequencies of recovery, despite the less-than-optimal conditions of exhumation of the skeletons. The high frequencies of non-skeletal materials obtained demonstrate the need for additional training and research given their informative power in forensic cases.

Preliminary study on sexual dimorphism of metric traits of cranium and mandible in a modern Italian skeletal population and review of population literature

This study aims to assess the sexual dimorphism of skull in a modern skeletal collection through a direct anthropometric methodology by using a logistic regression analysis as statistical approach in order to provide specific regression formulae for the Italian population. Thirtyfour measurements (24 from cranium, 10 from mandible; 33 linear distances, one angle) were taken on 80 individuals (40 males, 40 females). A stepwise discriminant function analysis selected the combination of variables which best discriminated between sexes, and a cross-validation assessed the accuracy rate of the original sample. Most distances resulted longer in males than in females, but differences were statistically significant only for 12 and 6 out of respectively 24 cranium and 10 mandibular distances. Five combined cranium features returned a prediction accuracy of 88.6% (y = -81.01 + 0.14* Maximum cranial length + 0.16* Basion-bregma height -0.05* Cranial base length +0.20* Bizygomatic breadth +0.31* Nasal height; adjusted R2 = 47.0%). Nine mandibular features were required to reach 74.7% accuracy (y = -93.08 + 0.19* Bigonial width +0.14* Bicondylar breadth +0.11* Mandibular length +0.18* Height of the mandibular body at mental foramen +0.21* Chin height -0.09* Mandibular angle -0.06* Minimum ramus breadth -0.05* Maximum ramus height -0.01* Maximum ramus breadth; adjusted R2 = 23.92%). Current results and existing literature suggested that only few cranial measurements can be used for diagnosis of sex: the same variables showed similar accuracy in different ethnic contexts. In conclusion, some aspects of sexual dimorphism of skull seem to be independent from ancestry.

The appearance of breast cancer metastases on dry bone: Implications for forensic anthropology

Breast carcinoma is a major cause of morbidity and mortality in women. The study of bone pathologies presents considerable potential in anthropology, paleopathology, forensic science and medicine. In this paper, we present and discuss metastatic lesions found in the skeletons of known individuals from the CAL Milano Cemetery Skeletal Collection, clinically diagnosed with breast cancer during life. Fourteen skeletons from a contemporary and identified collection were macroscopically studied and metastases were identified by comparison with clinical literature. As a result, bone metastases were observed in 43% of the study sample. They were located most commonly on the ribs (28.1%), pelvic girdle (19.8%), vertebrae (15.6%), skull (15.6%), scapulae (10.2%) as well as proximal segment of the femora (8.4%) and humeri (2.4%) respectively, favoring sites of high vascularization. The majority of the lesions were osteolytic, although osteoblastic and mixed metastases did occur. Osteolytic metastases appear as coalescent porosity or round to oval perforating lesions on bones with denticulated margins and pitted surrounding bone, whereas osteoblastic metastases thickened the existing trabecula (spongiosclerosis). Mixed metastases were perforating lytic lesions exposing the osteoblastic activity in the underlying trabecular bone. These results, consistent with the data from the literature, strengthen the diagnostic criteria for metastases and illustrate the aspect of bone metastases in breast carcinoma.

How do skeletons with HIV present? A study on the identified CAL Milano Cemetery Skeletal Collection

With the Human Immunodeficiency Virus (HIV) infection and Acquired Immune Deficiency Syndrome (AIDS) pandemic, the study of HIV/AIDS on bones has become of pivotal interest for research in bone pathologies, forensic applications (especially in the matter of identification when confronted to antemortem data) and medical purposes. In this paper, we document and discuss the macroscopic lesions found on the skeletons of nine individuals with known HIV, including four with known AIDS, coming from the identified CAL Milano Cemetery Skeletal Collection. As a result, several types of lesions were observed on bones: periosteal new bone formation, dental lesions, thickening of the frontal diploë, destructive localized porosity and evidence of trauma. None of the lesions reported can be directly linked to HIV because the virus does not directly affect bones in a macroscopic way. However, HIV/AIDS-induced infections and inflammations and HIV-related risk factors may leave bone markers. The differential diagnosis of each of the lesions noted in this research and its potential link to HIV or AIDS was discussed. Although it is not possible to diagnose HIV on bare bones, this was not the focus of this study. To our knowledge, no anthropological study has ever been performed on known HIV individuals. With this paper, we present for the first time skeletons with known HIV.