Unit:
Faculty of MedicineLibrary of the School of Health Sciences
Dissertation committee:
Κωνσταντίνος Μωραΐτης, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Χάιδω Σπηλιοπούλου, Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Χριστίνα Παπαγεωργοπούλου, Καθηγήτρια, Τμήμα Ιστορίας και Εθνολογίας, Δημοκρίτειο Πανεπιστήμιο Θράκης
Δημήτριος Βλαχοδημητρόπουλος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Μαρία Πιάγκου, Αναπληρώτρια Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Έλενα Κρανιώτη, Αναπληρώτρια Καθηγήτρια, Ιατρική Σχολή, Πανεπιστήμιο Κρήτης
Εμμανουήλ Σακελλιάδης, Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Original Title:
Προσδιορισμός της ανατομικής θέσης και αλληλοδιαδοχής των τυπικών θωρακικών σπονδύλων με μεθόδους τρισδιάστατης γεωμετρικής μορφομετρίας: Εφαρμογή στην Ιατροδικαστική διερεύνηση κατακερματισμένου σκελετικού υλικού
Translated title:
Positioning and sequencing of thoracic vertebrae through 3D geometric morphometrics: Application in the forensic investigation of commingled human remains.
Summary:
In events of mass disasters, such as the recent fires in Eastern Attica, Forensic Science is called upon to classify a large number of commingled remains. The main aim is to sort the commingled remains and attribute them to their families. However, a widely accepted method has not yet been developed to solve this specific issue. For this reason, the present doctoral thesis carried out in the Forensic Anthropology Unit of the Forensic and Toxicology Laboratory aimed at developing a method to determine the anatomical position and the sequence of the typical thoracic vertebrae with three-dimensional geometric morphometric techniques. The skeletal material used for the present research is from three different geographical contexts and from two different chronological periods. A total of 98 skeletons, of adult individuals, and specifically skeletons that had at least two to eight consecutive typical thoracic vertebrae. A total of 623 vertebrae were scanned using the Artec Space Spider 3D structured light scanner, which provides high-resolution 3D models that can be used for 3D geometric morphometry analyses. The free software PAST software package (Past4Project, version 4.03) was used for the process of statistical processing of the "raw" coordinates of the 3D landmarks placed in the generated models, and also for the analysis of the Procrustes superposition. To evaluate the applicability of the proposed methodology, the difference of the measurements using the caliper on the dry bone as well as on the produced 3D models was examined. The repeatability of the placement of the landmarks was also studied. Both for the succession of the vertebrae as well as for the determination of the anatomical position of the vertebrae, an intra-observer and interobserver test was performed. The results of these two tests were examined with a technical error of measurement (TEM) and presented a rate of less than 1.5% and 2% respectively. This indicates that the methodology can also be replicated by other researchers. At the same time, a blind test was carried out concerning both aims of the research. Initially, to determine the anatomical position of the vertebrae and therefore, their classification per person, the method was applied to an additional pair of consecutive thoracic vertebrae. In addition, to study the succession of typical thoracic vertebrae, the protocol was applied to a case of the Forensic Anthropology Unit. In both assessments, homogeneity of the results with those presented in the main study was observed. The methodology can be applied to a sample of individuals regardless of sex and therefore, when studying skeletal material, sex determination is not required. Assessment of the anatomical position of the typical thoracic vertebrae is most reliable for the T2, T3, T4 vertebrae and least reliable for the lower thoracic. The classification of vertebrae by individual and the determination of their anatomical position in relation to the superior or inferior vertebra of the same individual seems to have better results when the bones compared are fewer (e.g., three pairs of T6-T7). The approach proposed is thought to work better as a means of rejecting some hypotheses, rather than an absolute certainty about the location or provenance of the bones. This occurs because it is possible to have more than one vertebra of a similar shape, but which are not in the same position in the spine, possibly due to the differentiation of the bones between individuals. For this reason, it is considered necessary to further investigate this issue both in a sample of another population and in fragmented bones, while at the same time, it should be noted that the probability of correct identification increases significantly when the final confirmation can be done macroscopically. Future research could focus on increasing the sample and also on applying the methodology to a different set of landmarks that might lead to different results. In the future the increase of landmarks or the use of semi-landmarks could be investigated as it is possible that the choice of landmarks of the present study played a role in the conduct of the results or did not contribute to significant differentiation. Therefore, in this doctoral thesis the possibility of applying a methodology based on three-dimensional geometric morphometry related to the management of the typical thoracic vertebrae and determining their position in the spine as well as their sorting per person that can be applied both in cases where the bones of different individuals are found together, as well as in the recording of individual court cases.
Main subject category:
Health Sciences
Keywords:
Forensic anthropology, Commingling, Geometric morphometrics, Thoracic vertebrae, Sequencing vertebrae
Number of references:
179
