Microcracking pattern in fractured bones: new approach for distinguishing between peri- and postmortem fractures.

Timing bone fractures is one of the main tasks of a forensic anthropologist, but still an uncertain diagnostic. In the literature, there are many macroscopic methods to distinguish perimortem from postmortem fractures, based on the distinct structural and mechanical properties of fresh and dry bones. However, this differentiation is still challenging, in particular when the bones are fragmented or still exhibit fresh properties. Although histologic analysis is often used as a complementary diagnostic tool in forensic pathology, its application in the evaluation of bone fractures is uncommon. The aim of this study was to investigate whether fractures of fresh bones reveal a distinct microcracking pattern compared to fractures of dry bones, in order to optimise the fracture timing. To this purpose, we histologically analysed perimortem and postmortem fractures in human humeri. The fresh bones were retrieved from traumatic autopsy cases, and the dry bones from donors which were experimentally fractured. Our results showed that the highest density and length of microcracks (MCKs) were found in the interstitial area of dry fractured bones, which may be considered a marker of postmortem damage. In fresh fractured bones, we generally observed a lower density of MCKs, but a higher proportion of osteonal MCKs, which may be considered a marker of perimortem trauma. In summary, the results of our exploratory study suggest that changes in intrinsic bone factors (mineral/organic components) result in a different microcracking pattern that can be used in fracture timing.

[Mesalazine renal lithiasis.] / Nefrolitiasis por Mesalazina.

Mesalazine (5-aminosalicylic acid, 5-ASA),is an anti-inflammatory drug well-established as first-line treatment in the management of inflammatory bowel disease. Nephritic colic has been described as an uncommonside effect, but very few mesalazine nephrolithiasis have been published in the literature, probably due to its underdiagnosis for not using appropriate methodology for calculi analysis. We present two cases of lithiasis in patients treated with mesalazine at high dosage, an adverse effect to betaken into account as a drug lithiasis and which is not even mentioned in the patient information leaflet.

La mesalazina (ácido 5-aminosalicilico,5-ASA) es un fármaco antiinflamatorio utilizado en primera línea del tratamiento de la enfermedad inflamatoria intestinal. Aunque se ha descrito la presentación de cólicos nefríticos como efecto adverso con su uso, apenas se encuentran publicados casos de nefrolitiasis medicamentosa por mesalazina, probablemente infradiagnósticado por no utilizar la metodología adecuada para el análisis de los cálculos. Presentamos dos casos de litiasis en dos pacientes tratados a altas dosis de mesalazina, efecto adversoa tener en cuenta y que ni siquiera es citado en la ficha técnica del medicamento.

Distinction between perimortem and postmortem fractures in human cranial bone.

Timing of cranial trauma is challenging in forensic cases and literature on the subject is scarce. This study analysed the macroscopic fracture patterns of perimortem cranial fractures and compared them to experimentally reproduced cranial fractures on dry human craniums. The results showed nine traits associated with fresh cranial fractures: undulated margin, flake defects, peels with peel defects, fissures, crushed margins, bridge, bone scales and beveling. All the traits appear on the outer table or on the inner table of the cranium. Although not all characteristics must be present at the same time in all cranial fractures, they do define a new perimortem fracture pattern. Statistical analyses showed that six of these traits (undulated margins, flake defects, crushed margins, bone scales, fissures and peels) are distinctly related with perimortem (fresh) bone conditions. Considering the most discriminant perimortem traits, a decision-making algorithm is developed as a probabilistic approach to distinguish peri- from postmortem cranial fractures with an accuracy of 87%. This algorithm allows the forensic practitioner to incorporate more confidence during cranial trauma evaluation.

Visualization and documentation of perimortem traits in long bone fractures using computed tomography.

Perimortem fracture patterns in long bones, defined in previous publications, include layered breakage, bone scales, crushed margins, flakes with flake defect, wave lines, and plastic deformation. The traits help professionals during trauma analysis to differentiate peri- from post-mortem fractures. This study will therefore investigate whether these traits can be recorded with Computed Tomography (CT) as the non-invasive 3D imaging technique is becoming more popular in forensic science. CT scans of macerated bone samples (n = 15; humerus: n = 1; ulna: n = 1; radius: n = 1; femur: n = 12) were investigated using multi-planar reconstructions (MPRs) and volume renderings. Tension lines and severe plastic deformation were visible on the individual multi-planar reconstructions (MPRs) and the 3D models. Additionally, layered breakage and flake defects were also clearly distinguishable on the volume renderings. Based on the results, CT imaging may be a useful and fast tool to document, visualize, and analyze findings of blunt force trauma.

Differentiation between perimortem trauma and heat-induced damage: the use of perimortem traits on burnt long bones.

Burnt human remains present a difficult interpretative dilemma to forensic pathologists and anthropologists. Distinguishing postmortem damage in long bones as a result of fire damage from perimortem fractures is an important challenge in trauma analysis. During our case investigation of a burnt body from a fiery car crash, distinct perimortem traits on long bone fractures were still distinguishable along the charred areas. Next to timing of fractures and shortening the perimortem time gap suggesting that the fractures occurred when soft tissue was still present, the traits make it possible to distinguish blunt trauma caused by the accident from heat-induced bone damage. Applying this specific perimortem pattern could be an additional macroscopic tool to interpret blunt force trauma more accurately in the analysis of burnt remains.

Intra vitam trauma pattern: changing the paradigm of forensic anthropology?

This study aims to improve a previous study that reported new traits to characterize a perimortem fracture pattern in human long bones. This second study aims to acquire further knowledge about these perimortem traits, specifically by improving the experimental setting-by using a Blunt Force Trauma Simulator-and increasing the sample size with a total of 43 autopsy specimens and 57 reproduced fractures. Additionally, we investigated whether these traits could be related to muscular contractions by adding axial compression in the experimentally fractured specimens. If intra vitam traits can be found, it would consequentially be more valuable for forensic anthropologists to shorten the perimortem period. We demonstrate that all traits are perimortem traits. Furthermore, based on our results, we see the tendency that the combination of traits-instead of the presence of each trait individually-may make it possible to distinguish intra vitam from perimortem fractures. This study confirms these distinct characteristics that can be valuable to utilize in the distinction between peri- and postmortem fractures.

Perimortem fracture pattern in ribs by blunt force trauma.

Literature on timing of rib trauma is scarce but remains challenging during forensic cases. This study analysed the macroscopic fracture patterns of perimortem rib fractures and compared them to experimentally reproduced rib fractures on fresh and dry ribs. Six distinctive macroscopic traits were found in ribs that might provide information about the timing of trauma, fracture mechanism and/or trauma circumstances. These traits are peels, folds, differential fracture edges, incomplete fractures, plastic deformation and longitudinal lines. Peels, folds and plastic deformation might provide information about trauma timing. Folds and different fracture edges might provide information about the fracture mechanism. Statistical analyses showed that longitudinal lines, folds and incomplete fractures might provide information about the trauma circumstances and that age might have an influence on the occurrence of complete fractures, longitudinal lines and peels (p ≤ 0.05). The new insights presented in this study might be valuable for forensic anthropologists in rib trauma analysis.

Black cracks: staining of fracture lines.

During the investigation of fresh bone fractures, it might be difficult to visualize all the fracture lines that could contribute to the interpretation of the biomechanics behind a fracture. To optimize the examination of the fracture, the bones should first be defleshed to expose the osseous surface. To reveal small fracture lines more clearly, we developed two easy, fast, cheap and non-destructive methods to enhance fracture lines and bone defects by coloring the fracture lines with ink. One method consists of cooking the bone in ink, and the second method uses capillary action for ink penetration. We strongly recommend the use of the latter method with Talens® Black Indian Ink for the clearest results.

New insights in the analysis of blunt force trauma in human bones. Preliminary results.

Determining the time of injury is an important but still a challenging task in forensic anthropology. In literature, many descriptions can be found to make a distinction between perimortem and postmortem fractures. Characteristics that are more related to fractures in fresh conditions, however, are not extensively investigated. This study compared 28 perimortem fractures from autopsies and 21 both fresh and dry experimentally reproduced human bone fractures. Preliminary results showed the following five distinct traits that might be related to perimortem conditions: layered breakage, bone scales, crushed margins, wave lines and flakes with matching flake defect. These distinct traits might not only be good estimators of perimortem trauma but also may be an indicator of trauma in intra vitam conditions, especially related with muscular reaction to injury. Furthermore, layered breakage seems to be a good trait to infer the biomechanics of trauma.