Daniele Gibelli

Unidentified bodies and human remains: An Italian glimpse through a European problem

The identification of cadavers (the main activity of forensic odontologists and anthropologists) is a crucial issue in forensic pathology, but the official entity of this problem is still poorly known in most countries, apart from a few American reports. In this article the authors present a descriptive study of unidentified decedents over a 14-year period (1995-2008) in Milan. The number of cadavers or human remains arriving at the morgue with no identity amounts to 454 - 3.1% of all autopsies at the Institute of Legal Medicine, with a mean of 32 unidentified subjects every year; 62% reached a positive identification in a period of time ranging from a few days to 10 years. 17% on an average remain unidentified. Most identification processes involved forensic odontology and anthropology. This study aims at revealing the problem and hopefully may provide some food for thought for forensic pathologists, anthropologists and odontologists so that they may focus on this issue and on possible solutions in their countries.

Histological Determination of the Human Origin of Bone Fragments

Abstract:  A frequently encountered task in the forensic scenario is verification of the human origin of severely degraded fragments of bone. In these cases histological methods which consider osteon size and morphology can prove to be useful. The authors in the present study verify the applicability of published algorithms to flat and subadult bones from human, dog, cat, cow, rabbit, sheep, pig, chicken, quail, and turkey samples. Metric analysis was performed on 2031 Haversian canals. Analyses carried out on human samples confirmed a success rate of around 70% on long adult bones; however the percentage of wrong answers was particularly high in the case of newborns and older subadults as well as on flat bones in general. Results therefore suggest that such regression equations should be limited only to bone fragments from long adult bones.

Forensic radiology and personal identification of unidentified bodies: a review

Personal identification of unidentified bodies is crucial for ethical, juridical and civil reasons and is performed through comparison between biological data obtained from the cadaver and antemortem material from one or more missing persons to whom the body may have belonged in life. The increasing applications of forensic radiology and the wide use of conventional radiography and computed tomography (CT) in routine clinical practice demonstrate the potential of these technologies as tools for verifying the correspondence between an unidentified body and an identity suspect. This paper reviews the literature concerning the application of forensic radiology to the difficult issue of personal identification. Despite the increasing importance of the comparison between radiographic and CT findings, numerous limitations still need to be overcome, including the fact that few forensic centres have access to sophisticated X-ray technologies and that the reliability of those technologies for detecting specific morphological traits and bone lesions is a matter of intense debate. In addition, as with other morphological methods for identification, comparisons between antemortem and postmortem data require standardisation and statistical analysis, especially in Europe where there are very few indications concerning the admission in court of evidence obtained by anthropological and radiological methods. In the future, with developments in radiographic technologies and increasing numbers of studies on their application to the forensic setting, radiology will become one of the most useful tools in the field of personal identification.RiassuntoL’identificazione personale dei cadaveri senza identità è cruciale per motivi etici, giuridici e civilistici, e viene eseguita tramite un confronto fra i dati del profilo biologico ottenuti dal cadavere e il materiale ante mortem di uno o più sospetti d’identità o persone scomparse. Le crescenti applicazioni della radiologia forense e l’ampio uso della radiografia tradizionale e della tomografia assiale computerizzata (TAC) nella comune pratica clinica mostrano la potenziale importanza di tali tecnologie come strumento di verifica della corrispondenza fra un corpo senza identità ed un sospetto d’identità. Questo studio vuole esporre una revisione della letteratura riguardante l’applicazione della radiologia forense al complesso ambito dell’identificazione personale; nonostante la crescente importanza del confronto fra radiografie ed immagini TAC, numerosi limiti aspettano ancora di essere superati; al momento infatti pochi istituti di medicina legale hanno accesso agli strumenti radiografici più sofisticati, e sta sorgendo un ampio dibattito sulla reale affidabilità di tali tecniche nell’identificazione di specifici tratti morfologici e lesioni su osso. Inoltre, cosÌ come altri metodi identificativi basati sul confronto morfologico, anche il confronto fra dati radiografici ante e post mortem richiede una standardizzazione ed un approfondimento statistico, specialmente in Europa ove esistono pochissime indicazioni sulla modalità di ammissione di una prova scientifica ottenuta tramite metodi antropologici e radiologici in un processo. In futuro, con lo sviluppo delle tecnologie radiografiche e l’aumento del numero di studi riguardanti la loro applicazione a contesti forensi, la radiologia diverrà uno degli strumenti più utili nel campo dell’identificazione personale.

Personal Identification by the Comparison of Facial Profiles: Testing the Reliability of a High-Resolution 3D–2D Comparison Model

Abstract:  Identification from video surveillance systems is frequently requested in forensic practice. The “3D–2D” comparison has proven to be reliable in assessing identification but still requires standardization; this study concerns the validation of the 3D–2D profile comparison. The 3D models of the faces of five individuals were compared with photographs from the same subjects as well as from another 45 individuals. The difference in area and distance between maxima (glabella, tip of nose, fore point of upper and lower lips, pogonion) and minima points (selion, subnasale, stomion, suprapogonion) were measured. The highest difference in area between the 3D model and the 2D image was between 43 and 133 mm2 in the five matches, always greater than 157 mm2 in mismatches; the mean distance between the points was greater than 1.96 mm in mismatches, <1.9 mm in five matches (p < 0.05). These results indicate that this difference in areas may point toward a manner of distinguishing “correct” from “incorrect” matches.

Gunshot residues on dry bone after decomposition--a pilot study.

Abstract:  Very little literature exists concerning radiochemical and microscopic analyses of gunshot wounds in decomposed material, and even less concerning skeletonized samples; the most advanced technologies may provide useful indications for the diagnosis of suspect lesions, especially if gunshot wounds are no longer recognizable. However, we know very little of the survival of gunshot residues (GSR) in skeletonized samples. This study examined nine gunshot wounds produced on pig heads which then underwent skeletonization for 4 years, and four gunshot entries on human heads from judicial cases which were then macerated to the bone in water; the samples underwent scanning electron microscopy coupled with energy dispersive X‐ray (SEM‐EDX) analysis. Positive results for GSR were observed only in four of the nine animal samples and in all four human samples. Among the human samples, two lesions showed Pb and Sb, one lesion only Pb, and one Pb, Sb, and Ba. This pilot study showed the survival of GSR in skeletal material and therefore the crucial importance of SEM‐EDX analyses on skeletonized material. Further studies are needed in order to ascertain the role of environmental modifications of GSR.

Detection of blunt, sharp force and gunshot lesions on burnt remains : a cautionary note

The study of skin and bone lesions may give information concerning type and manner of production, but in burnt material modification of tissues by the high temperatures may considerably change the morphological characteristics of the lesions. This study aims at pointing out the effects of burning head of pigs with several types of lesions (blunt trauma, sharp force, and gunshot lesions) on soft tissues and bones, both from a morphological and chemical point of view. Results show that the charring process does not completely destroy signs of lesions on bones, which can often be recovered by cleaning bone surface from charred soft-tissue residues. Furthermore, neutron activation analysis test proved that antimony may be detectable also on gunshot entry wounds at the final stages of charring process.

Macroscopic, microscopic, and chemical assessment of gunshot lesions on decomposed pig skin.

Abstract:  Very little literature exists on gunshot wounds on decomposed material. In this study, seven pig heads underwent a shooting test. Entrance wounds from the first head underwent neutron activation analysis (NAA) and histological testing immediately after the firing test; the other six heads were exposed to two different environments (open air and soil) and analyzed by radiochemical and histological tests every 15 days. Gunshot wounds in air maintained their morphological characteristics, and those in soil showed severe alteration after 5 weeks. Microscopic testing verified positive results for lead in all gunshot wounds in open air, whereas in most of those in soil lead could not be detected. Radiochemical analysis performed by NAA yielded for all gunshot wounds but one antimony quantities in the range of 0.07–13.89 μg. In conclusion, it may be possible to detect residues of antimony even in degraded tissues.

Detection of metal residues on bone using SEM-EDS—Part II: Sharp force injury

Scanning electron microscopy coupled with X-ray energy dispersive spectrometry (SEM-EDS) is extensively seen in the literature for the improvement of the macroscopic analysis of sharp lesions, but very few indications concerning its real potential in the forensic context, particularly in forensic anthropology, are at the moment available. This paper represents a pilot study for the analysis of the behaviour of metallic residues found on bone after sharp force injury. Fourteen lesions were made on human bone (radius), cleaned of all soft tissues, with seven different sharp tools (three metal instruments, three metal saws and a baked-clay knife). Tools and lesions underwent SEM-EDS. From 3 to 18 particles were detected on each lesion, whose diameter was included between 0.5 and 150 μm. In 58% of cases, particle composition was concordant with the instrument used. The results seem to suggest that sharp force injury frequently leaves relatively few residues on bone, particularly in the case of common types of metal. Saws showed slightly more contamination with other residues than knives, which may be explained by the capability of the saws teeth to retain the residues of previously encountered material. In addition, metal residues related to the tool used to cut the bone were located on the edges/walls of lesions in the case of saw marks, whereas they were more frequently found on the kerf floor in the case of knives/scissors, with the exception of the baked clay knife which when it leaves residues at all, seemed to leave them equally divided between the floor, the edges and the surrounding bone.

Diatom extraction with HCl from animal tissues: A technical note

Identification of diatoms from human or animal tissue may be affected by factors concerning techniques of extraction and analysis which cause fragmentation or loss of diatoms. In this brief technical note a novel efficient method of extraction of diatoms from animal tissues is presented. The authors have tested an H(2)O(2) plus HCl and HCl method to detect diatoms in several tissues from pig immersed in water rich in diatoms; they have also compared this method to other methods of extraction including enzymatic ones. The experiment showed that all siliceous frustules of fresh water diatoms are resistant to the treatment proposed and are still recognizable after the digestion. Among the different tests, treatment by 20% HCl (T1) proved to be more simple and time-saving, and seems to be a valuable diagnostic tool for routine forensic procedures in the extraction and detection of diatoms. The positive results obtained in all cases should lead to further studies in order to evaluate the reliability of the proposed methods also from a quantitative point of view.

The importance of an anthropological scene of crime investigation in the case of burnt remains in vehicles: 3 case studies

Inspection of a crime scene is a crucial step in forensic medicine, and even the methods taught by forensic anthropology are essential. Whereas a thorough inspection can provide crucial information, an approximate inspection can be useless or even harmful. This study reports 3 cases of burnt bodies found inside vehicles between 2006 and 2009 in the outskirts of Milan (Italy). In all 3 cases, the victim was killed by gunshot, and the body was burnt in the vehicle to destroy signs of skeletal injury and prevent identification. In every case, the assistance of forensic anthropologists was requested, but only after the inspection of the body at autopsy showed that the remains were incomplete, thus making it more difficult to determine the identity, cause, and manner of death. A second scene of crime inspection was therefore performed with strict anthropological and adapted archeological methods by forensic anthropologists to perform a more complete recovery, proving how much material had been left behind. These cases clearly show the importance of a proper recovery and of the application of forensic anthropology methods on badly charred bodies and the importance of recovering every fragment of bone: even the smallest fragment can provide essential information. Thus, a precise coordination, a correct and thorough recovery of bone fragments, and an anthropological approach are crucial for many issues: analysis of the scene of crime, reconstruction of the corpse, and reconstruction of the perimortem events.