Frank Ramsthaler

Influence of the examiner’s qualification and sources of error during stage determination of the medial clavicular epiphysis by means of computed tomography

Computed tomography (CT) of the medial clavicular epiphysis has been well established in forensic age estimations of living individuals undergoing criminal proceedings. The present study examines the influence of the examiner’s qualification on the determination of the clavicular ossification stage. Additionally, the most frequent sources of error made during the stage assessment process should be uncovered. To this end, thin-slice CT scans of 1,420 clavicles were evaluated by one inexperienced and two experienced examiners. The latter did the evaluations in consensus. Two classification systems, a five-stage system and a substaging system for the main stages 2 and 3, were used. Prior to three of his six assessment sessions, the inexperienced examiner was specifically taught staging of clavicles. Comparison of the examiners’ results revealed increasing inter- and intraobserver agreements with increasing state of qualification of the inexperienced examiner (from κ= 0.494 to 0.674 and from κ= 0.634 to 0.783, respectively). The attribution of a not-assessable anatomic shape variant to an ossification stage was identified as the most frequent error during stage determination (n= 349), followed by the overlooking of the epiphyseal scar defining stage 4 (n= 144). As to the clavicular substages, classifying substage 3a instead of 3b was found to be the most frequent error (n= 69). The data of this study indicate that κ values must not be considered as objective measures for inter- and intraobserver agreements. Furthermore, a high degree of specific qualification, particularly the knowledge about the diversity of anatomic shape variants, appears to be mandatory and indispensable for reliable evaluation of the medial clavicular epiphysis.

High-resolution flat-panel volumetric CT images show no correlation between human age and sagittal suture obliteration—Independent of sex

This study investigated whether digital, high-resolution CT-images of the internal human sagittal suture structure include information that enables a novel method of age at death (aad) determination. To accomplish this, coronal, flat-panel-based volumetric computed tomography (eXplore Locus Ultra scanner) images were automatically analyzed by a software implementation of an algorithm that determines user independent whether a suture is open or closed. 29,205 images of the local vicinity of the sagittal suture of 164 males and 85 females of European descent were investigated separately for both sexes. We used conditional probabilities and a chi(2)-test to investigate whether there is a correlation between aad and suture obliteration or not. The computer-aided analysis enables us to handle huge volumes of data that could not otherwise be analyzed within a reasonable time frame. The implemented algorithm ensured a strongly reproducible, reliable, accurate, and fast differentiation between closed and open sutures. The evaluation of various statistical parameters suggests that there is no reason to assume a correlation between age and suture closure--with equal findings for both sexes. Therefore, we conclude that determination of aad based on the evaluation of sagittal suture obliteration is not possible. This agrees well - thus unsatisfactorily - with the recent literature.

Analysis of laryngeal fractures in decomposed bodies using microfocus computed tomography (mfCT)

Postmortem computed tomography (CT) is now routinely performed in forensic autopsies. Microfocus computed tomography (mfCT) has attracted recent attention because it can provide more detailed information than routine postmortem CT can. This feasibility study evaluated the usefulness of mfCT for examination of the hyoid bone and thyroid cartilage in cases of suspected strangulation, where advanced decomposition precludes detection of petechial hemorrhages and hemorrhages adjacent to fractures. The results show that mfCT was useful for identification of thin fracture lines in the fragile laryngeal structures. We suggest that mfCT should be considered for forensic autopsies in cases of suspected strangulation with advanced decomposition.

The ring phenomenon of diluted blood droplets

Bloodstain pattern analysis is occasionally required in practical forensic casework. Misinterpretations may occur in cases in which diluted bloodstains are formed either within the course of the crime or during cleaning attempts after the original crime. The resulting pale or diluted aspect of the bloodstains may also be produced by passive serum separation. To differentiate between diluted and non-diluted stains and the artifacts of pure serum separation, dripping experiments were performed using droplets of multiple sizes and dilutions dripped onto common indoor and fabric surfaces. In addition, pools of blood of different volumes were applied to solid surfaces with different inclinations to determine the conditions and properties of serum separation. This study yielded morphological characteristics that enable differentiation between stains of diluted and non-diluted blood: a prominent ring phenomenon indicates dilution with water. To elucidate the underlying physical mechanism of particle distribution within a blood stain, photomicrographs were taken during the drying process. The so-called contact line pinning effect was identified as the formation mechanism of this ring phenomenon. Serum separation was highly dependent on the applied blood volume, the ambient temperature, the time elapsed since the initial deposition, and the degree of floor inclination.

Optimising magnetic resonance imaging-based evaluation of the ossification of the medial clavicular epiphysis: a multi-centre study

Evaluation of the ossification of the medial clavicular epiphysis plays a key role in forensic age estimation, particularly in determining whether the age of 18 has been attained. A key research objective in the forensic age estimation field at present is to establish non-X-ray methods for investigating the clavicle. This paper looks at the use of magnetic resonance imaging for evaluating the developmental state of the medial clavicular epiphysis. Clavicle specimens obtained from autopsies of 125 female and 270 male subjects aged from 10 to 30 were examined using a 3-T magnetic resonance scanner. One FFE-3D-T1 gradient echo sequence and one 2D-T2 turbo spin echo sequence were acquired. In each case, two investigators undertook a consensual determination of the ossification stage of the medial clavicular epiphysis using recognised classification systems. To determine intra-observer and inter-observer agreement, 80 clavicle specimens were subjected to repeat evaluation. We present statistics relating to the ossification stages. The inclusion of established sub-stages of clavicular ossification offers an additional option for determining whether a subject has attained the age of 18 which is applicable in both sexes. For both sexes, the minimum ages for ossification stages 4 and 5 allow conclusions to be drawn about a subject’s age at a point in time lying several years in the past. Magnetic resonance imaging is a valid investigatory procedure for determining the ossification stage of the medial clavicular epiphysis. This paper makes a contribution to expanding the range of methods available for forensic age estimation.

Comparison of imaging planes during CT-based evaluation of clavicular ossification: a multi-center study

Determining the ossification stage of the medial clavicular epiphysis by computed tomography represents the currently recommended methodology for the question of whether a living individual has completed the 18th or 21st year of life. In the present study, thin-slice CT scans of 1078 sternoclavicular joints were reconstructed in axial and coronal image series and evaluated according to the two classification systems established for age diagnostics using the clavicle. Both image series (axial and coronal) were analyzed separately. When comparing the results of axial and coronal view, a different ossification stage was found in 35.6% of the clavicles. The results suggest an influence of the imaging plane on the process of stage determination. In order to further approximate the three-dimensional and asymmetrical structure of the epiphyseal ossification center, the usage of at least two different reformation types may be recommended. In practice, only those reference studies should be applied which exactly employed the same number and orientations of the reformation types that are going to be used in the respective routine case.

The face of war: Trauma analysis of a mass grave from the Battle of Lützen (1632)

Contemporary accounts of battles are often incomplete or even erroneous because they reflect the—often biased—viewpoints of the authors. Battlefield archaeology faces the task of compiling an historical analysis of a battle and of gathering all the available facts. Besides cultural historical evidence and artefacts, the human remains of those who have fallen in battle also provide invaluable information. In studying mass graves from a military context, the injury types and patterns are significant. They allow us to reconstruct the circumstances surrounding the soldiers’ deaths and provide information on the hostilities that occurred on the battlefield. One such mass grave was discovered in 2011 at Lützen, Saxony-Anhalt (Germany). Based on its geographical location and on the results obtained from archaeological examinations carried out in the area, the grave could be dated to the Thirty Years War (1618–1648). Further archaeological research confirmed that the dead had been soldiers from the Battle of Lützen (1632). The mass grave was block-lifted and then comprehensively examined at the State Museum of Prehistory in Halle (Saale). As well as osteological examinations to determine age, sex, height, state of health, i.e. diseases or injuries, imaging methods were also employed and histological and isotopic analyses carried out. The focus of this study was on the injuries sustained by the soldiers both prior to and during the battle. The results revealed that the 47 deceased had been between the ages of 15 and 50 when they died. Numerous healed injuries showed that the men had often been involved in violent encounters. Approximately three in every four soldiers had injuries that could have been fatal. Wounds inflicted by handguns, particularly to the skull, were predominant. The integrative analysis of the archaeological and anthropological data allowed us to conclude that the majority had been killed during a cavalry attack.

Bergung von menschlichen Überresten mit starker Brandzehrung

ZusammenfassungBei stark brandgezehrten menschlichen Überresten gewinnt die forensisch-osteologische Expertise an Bedeutung. Ein wichtiger Aspekt, von dem der Erfolg der nachfolgenden Untersuchungen oft entscheidend abhängt, ist das Bergen von Brandleichen. Folgende Fundkonstellationen von Brandopfern bzw. deren Überresten sind in der Praxis relevant: Bergung aus Gräbern bzw. Vergrabungsplätzen, Bergung aus Gebäuden und Bergung aus Fahrzeugen. Ein sich nach der Bergung anschließender wichtiger Vorgang ist der Transport der geborgenen menschlichen Überreste bis zum eigentlichen Ort der Untersuchung. Interdisziplinär geplante und durchgeführte Bergungen mit anthropologischer Expertise am Bergungsort und unter Einsatz archäologischer Techniken bieten die besten Voraussetzungen für die nachfolgenden Untersuchungen.AbstractThe expertise of forensic osteologists is called for when badly burned human remains are found; however, adequate recovery of these often fragile remains is critical to the success of the ensuing examinations. In practice the following situations are frequently encountered: the recovery of burned human remains from graves or burial sites, from buildings and from vehicles. Correct transportation of the recovered remains from the discovery site to the examination venue is a further critical aspect affecting the outcome of the forensic examination. An interdisciplinary approach to planning and performing such recovery actions that combines anthropological expertise and archeological techniques at the discovery site offers the best conditions for the success of subsequent analyses.

Morphometric investigations to assess the compatibility of mandible and skull

When a morphologically separated skull and mandible are found in the same case context, the possibility of a match arises. Two criteria with which to determine a match are the rough articulation between the mandibular condyles and cranial base itself and, most importantly, the fit of the teeth. However, when there has been intravital or postmortem tooth loss, this important criterion is not available. To date, only Reichs (1989) has investigated further compatibility criteria to solve the question of putative commingling in a case where a mandible seemed to originate from a female, while all other bones originated from a male individual. In a different reported case (Preißler et al. 2017), a mandible seemed too big for a skull; DNA analysis, however, confirmed that both originated from the same female individual. To investigate the metric relationship between mandible and skull we measured the postmortem CT data records of 223 corpses (virtual skulls) in OsiriX© MD for the following linear parameters: bicondylar breadth (KDB), biradicular breadth (AUB), and bizygomatic breadth (ZYB). The indices KDB/ZYB and KDB/AUB were developed and used to define ranges for matches and mismatches. Furthermore, the intra-observer reliability for the method was assessed. An intraclass correlation coefficient of >0.99 for every parameter showed that the used measurements are highly reliable. The 2.5-97.5 percentile for the KDB/AUB index lay between 0.91 and 1.05, while the range for the KDB/ZYB index was between 0.87 and 1.00. Within these ranges, it is possible to roughly assess whether or not a mandible and skull might be compatible, even if this can only be verified by forensic DNA analysis. If an index value lies outside these ranges, it can be assumed that skull and mandible do not match. Future studies should include more samples from a broader population spectrum so that these metric relationships can be used for different populations.

Current Practice of Forensic Anthropology on Dead Bodies

A badly decomposed cadaver is found. Preliminary investigations confirm the human specificity and suggest that the remains are contemporary and represent one unknown individual. Because the remains are so badly decomposed, it is impossible to recognize identifying characteristics such as facial features, external sex organs, or tattoos. Furthermore, fingerprints can no longer be obtained. In such cases, the first forensic anthropological objective is to identify the decedent by establishing a biological profile. Conventional osteological methods are used to estimate the decedent’s sex, age at death, body height, and ancestry. Where needed, a CT scan may be performed and the examinations conducted on virtual bones. Bony scars and dentition status can also provide further identifying clues. If the biological profile suggests a match with a missing person, further methods such as radiographic comparison, skull-photo superimposition, dental status, or forensic DNA analysis are used to confirm the decedent’s personal identity.