Micro-CT in a forensic examination of a fatal child abuse case: A case report.

Child abuse is a serious concern that can cause the death of a child. In such cases the medico-legal evidence is often pivotal but complex, drawing across multiple medical disciplines and techniques. One key specialism is histopathology, which is considered the gold standard for estimating the age of individual fractures. Another is micro-CT imaging, which can visualise the location of trauma across the body. This case report demonstrates how micro-CT was used to contextualise the histological evidence in the Criminal Justice Proceedings of a fatal child abuse case. This was achieved by overlaying the aged fracture evidence from histopathology onto the visuals rendered from micro-CT imaging. The case was a suspected child abuse of a deceased 1-month old infant who was reported unresponsive by their parents. The child was taken to hospital where they were pronounced dead. Suspicion was raised and post-mortem imaging confirmed head trauma and rib fractures, and the case was escalated for a forensic investigation. This case report details how the micro-CT imaging was merged with the gold standard of histopathology for visualisation of trauma, and how the court presentation was planned alongside Senior Investigating Officers and various medical experts. The presentation was used in court by the histopathologist to present the evidence. The resulting presentation provided additional clarity to jury members regarding the location, severity, frequency, and timings of the injuries. From the perspective of the investigating police force, the resulting presentation was crucial in ensuring understanding of the medico-legal evidence of how the infant died. The prosecuting lawyer noted that combining the histological and micro-CT evidence in this way allowed the evidence to be presented in a sensitive, clear, and impactful manner.

Micro-CT for the examination of paediatric rib injuries: A case series.

Cases of child abuse and homicide are amongst the biggest challenges investigators face, with complex evidence bases often strongly contested and reliant on specialist interpretation of the medical evidence. In many cases, this medical evidence includes examination of the deceased's skeleton using different macroscopic and microscopic imaging methods. Rib fractures are a common concern when examining suspicious cases and much research has been conducted on their causes. The role of CPR in particular has been controversial and therefore a clear assessment of the fracture distribution is crucial. Recent studies have shown the benefit of imaging techniques such as Computed Tomography, although the gold standard remains histology. This paper presents three cases of suspected non-accidental rib fractures of infants which had been examined using micro-CT and histology. Micro-CT has been shown to be superior to medical CT as it achieves a greater resolution, making it effective for paediatric post-mortem imaging. Micro-CT observations were compared retrospectively to the histology, which demonstrated that micro-CT found 69% of the fractures identified histologically as well as an additional 22% not identified through histology. As well as complimenting histological analysis, the extent to which micro-CT can enhance the overall examination of paediatric non-accidental injuries is also discussed.

Experimental study exploring the factors that promote rib fragility in the elderly.

Rib fractures represent a common injury type due to blunt chest trauma, affecting hospital stay and mortality especially in elderly patients. Factors promoting rib fragility, however, are little investigated. The purpose of this in vitro study was to explore potential determinants of human rib fragility in the elderly. 89 ribs from 13 human donors (55-99 years) were loaded in antero-posterior compression until fracture using a material testing machine, while surface strains were captured using a digital image correlation system. The effects of age, sex, bone mineral density, rib level and side, four global morphological factors (e.g. rib length), and seven rib cross-sectional morphological factors (e.g. cortical thickness, determined by µCT), on fracture load were statistically examined using Pearson correlation coefficients, Mann-Whitney U test as well as Kruskal-Wallis test with Dunn-Bonferroni post hoc correction. Fracture load showed significant dependencies (p < 0.05) from bone mineral density, age, antero-posterior rib length, cortical thickness, bone volume/tissue volume ratio, trabecular number, trabecular separation, and both cross-sectional area moments of inertia and was significantly higher at rib levels 7 and 8 compared to level 4 (p = 0.001/0.013), whereas side had no significant effect (p = 0.989). Cortical thickness exhibited the highest correlation with fracture load (r = 0.722), followed by the high correlation of fracture load with the area moment of inertia around the longitudinal rib cross-sectional axis (r = 0.687). High correlations with maximum external rib surface strain were detected for bone volume/tissue volume ratio (r = 0.631) and trabecular number (r = 0.648), which both also showed high correlations with the minimum internal rib surface strain (r = - 0.644/ - 0.559). Together with rib level, the determinants cortical thickness, area moment of inertia around the longitudinal rib cross-sectional axis, as well as bone mineral density exhibited the largest effects on human rib fragility with regard to the fracture load. Sex, rib cage side, and global morphology, in contrast, did not affect rib fragility in this study. When checking elderly patients for rib fractures due to blunt chest trauma, patients with low bone mineral density and the mid-thoracic area should be carefully examined.

The potential of micro-CT for dating post-cranial bone fractures: a macroscopic, radiographic, and microtomography study of fractures of known post-traumatic ages.

The estimation of the post-traumatic survival time (PTST) in case of bone injuries remains a tricky issue in the forensic field, especially when dealing with dry bones. Newer high-resolution imaging, and in particular microcomputed tomography (micro-CT), has the potential to significantly improve our abilities to interpret antemortem and perimortem lesions and accurately date fractures in a less destructive analysis. In this paper, nine costal fractures of known post-traumatic ages were analyzed through gross examination, conventional radiography, and microcomputed tomography, in order to test the potential of microcomputed tomography for dating fractures. As a result, microcomputed tomography provided images of high quality and definition and allowed the observation of the internal microarchitecture of the fractures and calluses. While microcomputed tomography cannot substitute histological examination for the estimation of the post-traumatic survival time, it constitutes a potent and helpful complementary tool for the analysis of bone trauma.

Spontaneous Chest Wall Herniation in Centrally Obese Patients: A Single-Center Experience of a Rare Problem.

BACKGROUND: Spontaneous rib fractures, especially in association with chest wall herniation, represent an uncommon pathology. As such, there are little data analyzing approaches to treatment or regarding the success of intervention. The goal of this study was to analyze our cumulative experience with this unusual condition. METHODS: A case series of 12 patients was gathered from a single institution based on outpatient visits between February 2015 and October 2018. Each chart was retrospectively reviewed with particular attention to age, gender, BMI, area of injury, and smoking history. Patients presented with complaints of dyspnea or pain related to rib fractures with or without intercostal neuralgia. Each of these patients was noted to have rib fractures with lung herniation either on imaging, outside hospital records, or physical exam. A thorough medical history was obtained with attempts to find common predisposing factors as well as data regarding any previous surgical intervention for their herniation. RESULTS: Nine of the 12 patients reviewed had recent or prior surgical intervention. Every patient seen in the clinic with a spontaneous fracture and herniation incidentally had a BMI >30 and was therefore classified as obese. Additionally, every patient who had a recurrence after their first surgical attempt at repair had a BMI greater than or equal to 35. All 12 patients seen at our institution were males. The failure rate of operative intervention was 66%. CONCLUSIONS: Obesity was a prevalent comorbidity in the patient population we reviewed. Given the role obesity plays in abdominal and hiatal hernia repair success rates, it should be considered that obesity is a significant contributor to chest wall herniation if rib fractures occur. With 66% chest wall repair failure, patient selection is critical in the success of surgical intervention. Perhaps additional patient optimization, especially weight loss, should be considered prior to surgery.

Rib histology after unsuccessful cardiopulmonary resuscitation in infants suffering sudden death from natural causes; implications for injury mechanism and timing.

AIMS: To describe whether haemorrhage into the fracture gap, bone marrow, or periosteum, and loss of osteocyte nuclei from infant rib fracture margins, are true markers of vitality or may be seen solely as a consequence of cardiopulmonary resuscitation attempts. METHODS AND RESULTS: A description is provided of histological findings in sampled rib fractures in a retrospective consecutive series of infants, aged 1 month to 1 year, who suffered sudden death. All had undergone cardiopulmonary resuscitation (CPR) and were investigated by use of skeletal survey, whole body computed tomography (CT), and invasive postmortem (PM). There was no suspicion of child abuse. 15 infants were studied, 9 of whom had anterior/anterolateral rib fractures; slides were available with consent for use in seven. Skeletal survey identified no fractures. CT and PM showed 46 fractures, 27 of which were examined histologically. Marrow cavity haemorrhage> 2 mm in diameter was seen in 55% of fractures; easily identifiable red cells were seen in the fracture gap in 36%, and beneath the periosteum in 36%. Loss of intact osteocytes from lacunae in bone fragments at the fracture margins relative to distant areas was obvious in 50% of fractures. CONCLUSIONS: Anterior rib fractures, visible on CT and histologically, are common after CPR in infants. Empty lacunae and bleeding into the fracture gap, into the marrow cavity and beneath the periosteum are all frequent in CPR-related infant rib fractures, and should not be used to discriminate between true in-vivo injury and perimortem injury.

A histological comparison of non-human rib models suited for sharp force trauma analysis.

Cut marks provide essential knowledge to interpret which and how tools were used, both in archaeological and forensic context. Lots of studies focused on experimentally produced cut marks on animal models to develop methods for stabbing incidents. However, animal models are criticized to be morphologically different in comparison to human bones. This study analyzed the bone composition and experimentally obtained cut marks done on ribs from humans, pigs and goats. Methods included a qualitative description of differences between the species and a quantitative analysis of the cut mark proportions in histological thin sections and micro CT scans. The results indicated that especially the cortical bone of non-human ribs was different in comparison to human bone tissue as they were more robust and usually juvenile. Plexiform bone dominates and remodeled lamellar bone is rarely visible. The knife impact tends to create debris inside the cut mark and stress fractures along lamellae and cement lines perpendicular to the cut mark. Moreover, entheses of the intercostal muscles are always affected by the incision. Pig ribs were shown to be better suited as a model for sharp force trauma than goat ribs in comparison to humans. Though, plexiform bone and non-remodeled bone made it not quite ideal. We suggested to use bone material from animals used for breeding instead of meat production as they are slaughtered at higher ages.

Forensic 3D printing from micro-CT for court use- process validation.

Forensic application of 3D scanning and printing technology is gaining momentum with 3D printed evidence starting to be produced for court. However, the processes for creating these forensic 3D models requires still rigorous assessment to ensure they adhere to the relevant legal standards. Although, previous work has examined the accuracy of 3D prints created from medical grade Computed Tomography (CT), no such assessment has been carried out for Micro Computed Tomography (micro-CT) which offers superior resolution and the ability to capture forensically relevant injuries. This study aimed to quantify the error rates associated with forensic 3D printed models and toolmarks, created using three different printing technologies, based on micro-CT data. Overall, 3D printed models, based on micro-CT scans, replicate bone surface geometry to sub-millimetre accuracy (<0.62mm for overall shape and <0.36mm for toolmarks). However, there were significant differences between the printing technology employed (mean errors of -0.3%, -0.8%, and 0.7% for shape geometry and -0.8%, 14.1%, and 0.7% for toolmark geometry for Printers 1-3 respectively). Where possible, the authors recommend micro-CT imaging for producing forensic 3D printed bone models particularly when injuries are present.

Morphology of direct and indirect rib fractures.

Rib fractures are a common finding in legal medicine and information on the impact mechanism is relevant for trauma reconstruction. This study focuses on morphological characteristics of rib fractures resulting from direct or indirect force. Fresh human ribs (n = 312) were divided into two groups and broken through local force (direct) and bending (indirect) in anterolateral areas. The ribs were macerated, visually investigated and the results statistically analysed. The indirect fractures showed a significant larger lateral offset of the internal and external fracture ends while the fracture ends of the direct fractures were more often straight, in line. Also, the morphology of the inner and outer fracture edges was significantly related to fracture type. Direct fractures mostly had rough and jagged inner edges (tension side) and straight, smooth outer edges (compression side), whereas indirect fractures more often showed the characteristics vice versa. The results were more convincing in combination and in ribs from persons aged ≤ 75 years at death. In summary, the direct and indirect rib fractures showed significantly different characteristics regarding orientation and offset of the fracture lines and roughness of the inner and outer fracture edges, which can be helpful to distinguish the traumatizing impact mechanisms in forensic autopsy routine.

Postmortem Computed Tomography and Magnetic Resonance Imaging of an Abdominal Gunshot Wound.

The use of postmortem computed tomography (CT) has been described in many articles concerning gunshot injuries. Postmortem magnetic resonance imaging (MRI) for better assessment of soft tissue injuries has also been mentioned in the literature, albeit much less often. The use of postmortem MRI for abdominal gunshot wounds has not been previously presented in the literature. The present case report describes the findings of an abdominal gunshot wound detected by postmortem CT and MRI, followed by an autopsy. The main imaging findings on CT were a hyperdense ring at the entrance wound, which indicated the muzzle imprint mark, a hyperdense region beneath the skin, which was suggestive of combustion residue, gas cavities surrounding the bullet path, which might be related to the temporary cavity, and a fracture of the 13th rib on the left. Magnetic resonance imaging provided a clear depiction of defects in the muscle tissue and peritoneal fat, as well as an injury to the left kidney and a large volume of blood in the abdominal cavity. Computed tomography combined with MRI provided a descriptive presentation of the intracorporeal trajectory noninvasively. Autopsy confirmed the radiologic findings but additionally revealed further relevant findings, which were not detected radiologically, such as a duodenal perforation. Autopsy also detected subendocardial hemorrhages and shock kidney, which were consistent with severe blood loss.The imaging findings and their interpretations are discussed in this case report, as well as the role of CT and MRI in the assessment of abdominal gunshot wounds compared with autopsy.

Patterned bruising indicating a complete renal artery transection in a fatal occupational accident.

Blunt renal artery injury (BRAI) is a rare finding with incidence ranging from 0.05% to 0.08% among blunt abdominal trauma patients. BRAI occurs in 1% to 4% of patients with renal injury, and the most common cause is motor vehicle accidents. An unusual case of BRAI in a 47-year-old man at work is reported. The victim accidentally fell from a scaffold (approximately 3 m in height). He was transported to the hospital where he was intubated, but he died after 30 min despite the cardio-pulmonary resuscitation. Surveillance cameras showed the man falling from the scaffold, but his impact with the ground was not captured. At autopsy, except for an oval bruise on the left hypochondrium, no external injury was found. The same mark was noticed on the shirt worn by the victim. Bilateral ribs fractures were found. The abdominal cavity was filled with 2 l of fresh blood and clots as a consequence of a complete transection of the left renal artery. Investigation of the workplace revealed a partial footprint on the external side of the scaffold, matching shoes worn by the victim. On the ground, a metallic pedestrian gate with a 1 m high post was found placed just below the scaffold. It was concluded that the man hit the gate's post as intermediate impact after the fall, which caused the oval bruise, ribs fractures, and the rupture of the left renal artery without injury of the internal organs.

Histologic and radiological analysis on bone fractures: Estimation of posttraumatic survival time in skeletal trauma.

In antemortem fractures, the estimation of the amount of time that has lapsed between the traumatic event and eventual death (the socalled 'posttraumatic survival time' or PTST) can have substantial implications in legal proceedings. It might for instance help to corroborate witness testimonies, to reconstruct the chain of events leading to eventual death or to establish a sequence when multiple traumata in a single individual are encountered. However, PTST estimation of bone trauma is impeded by a myriad of theoretical and practical issues, and is therefore almost invariably considered challenging. A few years ago, a method that combines radiological and histological analysis of fractures to estimate the minimum amount of lapsed PTST in skeletonized remains was proposed. This study aims to test its accuracy on a set of five rib fractures and four skull lesions fractures with known and varying amounts of posttraumatic survival time. In addition, it explores the differences between the assessment on ribs and skull bones and it expands on the proposed method by including computed tomography (CT) scanning. Using conventional radiology and histology, the minimum amount of PTST was accurately estimated in 8 out of 9 of the cases (89%). The one discrepancy between the estimated and known PTST was minimal, being just one day. The precision of the method diminishes as healing advances. It was noted that skull lesions showed less advanced and less well-developed healing features than the lapsed PTST would suggest. Of the three used modalities, conventional radiology proved to be the least accurate. CT scanning proved to be a valuable, sometimes even superior alternative to conventional radiology. Histology was superior to both conventional radiology and CT scanning. The results of our study illustrate the potential of the combined application of radiology and histology to estimate the PSTS in skeletonized human fractures.

Rib soft fixation produces better analgesic effects and is associated with cytokine changes within the spinal cord in a rat rib fracture model.

Traumatic rib fracture can cause severe pain and is usually associated with the depression of respiratory drive followed by severe respiratory complications. It is critical for patients with rib fracture to receive adequate analgesia. However, strong opioids and other analgesics often produces side effects and may even cause respiratory suppression. Meanwhile, rib fixation now has become a popular method for treating rib fracture patients. However, the actual molecular mechanism leading to its effectiveness as an analgesia has not been fully investigated, and the best analgesic method for its use in rib fracture patients has not yet been determined. We developed a new animal model for rib fracture and evaluated changes in pain severity after rib fixation. Our data indicated significantly better analgesic behavior if a soft string rib fixation is performed, which is associated with cytokine (interleukine-6 and interleukine-10) decreases in the spinal cord and co-localization with glia cells. Our results provided a treatment suggestion for rib fracture patients and the possible molecular mechanism for the analgesic effects. Further molecular mechanisms and the best therapeutic methods are still needed for this severe painful condition.

Using histology to evaluate micro-CT findings of trauma in three post-mortem samples - First steps towards method validation.

Forensic imaging technology has rapidly advanced over the past several decades and is gaining increasing significance in medico-legal death investigations. Medical-grade computed tomography (CT) is now routinely used in post-mortem examinations at numerous institutions across the globe. However, the resolution of medical-grade CT is limited and unsuitable when used to depict some smaller anatomical structures or micro-trauma. High-resolution micro-CT offers up to 100× the resolution to overcome this problem but is a very recent addition to the field of forensic radiology. Few studies so far have attempted to validate the results which is an essential prerequisite for it to be used in the criminal justice process as demanded by regulatory bodies. This study directly compares micro-CT images with histology, the current gold standard. Three cases were examined: two larynges from suspected strangulations and one ribcage of a case of fatal child abuse. A strong correlation was observed between histology and micro-CT as the majority of skeletal injuries were identified correctly. This paper discusses the forensic implications of the results and how micro-CT is complementary to histology.

Fatal delayed hemopericardium and hemothorax following blunt chest trauma.

Cardiac injury following blunt chest trauma is common in motor vehicle accidents due to a crush or blast injury. Severe cardiac trauma is associated with a very high mortality. If a cardiac injury develops several weeks after non-penetrating chest trauma, establishing a causal link between the traumatic event and the cardiac injury becomes complicated. This article reports a case of fatal delayed hemopericardium and hemothorax following a motor vehicle accident including blunt chest trauma 34 days prior to death. The cardiac injury was caused by displacement of a sharp irregular fragment of one of the decedents fractured ribs and the primary defect was sealed by blood clots. Subsequent bleeding occurred when the thrombus was displaced. Since the incidence of blunt high-energy chest injuries is relatively high, heart and large vessel injuries must be taken into account and a comprehensive examination needs to be done in order to prevent the delayed development of fatal complications.

Cardiac Ventricular Laceration Due to Child Abuse: Abusive Ventricular Laceration.

Traumatic cardiac ventricular ruptures in children are rare. Only a single case of left ventricular rupture due to child abuse has been reported. We report a child who sustained a fatal left ventricular apical rupture. It appeared to have resulted from hydrostatic forces resulting from abusive blunt thoracic injury. That he was being abused was previously missed when he was presented to the emergency department with facial pyoderma. It was not noted that he also had lip and oral mucosal injury, sites not affected by staph toxins. As a result, his underlying, abusive and secondarily infected, facial flow type scald burn was not appreciated. Within a week thereafter his fatal injury occurred, accompanied by extensive and obvious associated abusive injuries. Postmortem high-detail whole body computed tomography scanning aided the autopsy. Although rare, ventricular rupture from abusive blunt thoracic injury can occur.

Severe Cardiac Rupture by Only One Blow to the Chest in a Young Boy: An Autopsy Case.

Cardiac rupture by blunt chest trauma is commonly seen after motor vehicle accidents and falls; however, it is rarely caused by a blow to the chest. We herein report an autopsy case of a high school boy who sustained severe right ventricular rupture by only one knee kick to the chest during a quarrel. He was hospitalized and developed cardiopulmonary arrest. Emergency surgery was performed, but the patient died. The autopsy revealed no external severe trauma or deformation, but the side wall of the right ventricle contained a large V-shaped laceration. The other thoracic organs had no injuries. This case illustrates that severe cardiac rupture can occur by only one blow to the chest. Blunt cardiac injuries can occur even if no severe injuries are present on the body surface. We should consider the possibility of severe cardiac injuries regardless of the presence of external injuries.

Early Signs of Fracture Repair in the Human Rib Cage: Implications for Forensic Casework.

The decomposed body of a woman discovered beneath a collapsed structure was examined at the C.A. Pound Human Identification Laboratory. Despite a mix of rib fractures with and without indications of healing, it is most likely that all fractures occurred as a result of a single, compressive event. Signs of intramembranous, and possibly direct, fracture healing at the incomplete fractures without signs of endochondral ossification at the complete fractures suggest the individual died very shortly-but not immediately-after injury. Given the case circumstances, the findings inform immediate cause of death. This case study highlights that differential healing as a result of a single event is possible. Further, it illustrates the importance of careful examination of micro-discontinuities/cracks that can occur in association with major fractures. Fracture healing and dating data are discussed, as is the possible need for critical evaluation of the antemortem/perimortem boundary.

Use of the Animal Trauma Triage Score, RibScore, Modified RibScore and Other Clinical Factors for Prognostication in Canine Rib Fractures.

OBJECTIVES: To characterize the clinical features among dogs sustaining rib fractures and to determine if age, type and severity of injury, entry blood lactate, trauma score and rib fracture score were associated with outcome. METHODS: A retrospective study was performed to include dogs that were presented with rib fractures. Risk factors evaluation included breed, age, body weight, diagnosis, presence of a flail chest, bandage use, puncture wound presence, rib fracture number, location of the fracture along the thoracic wall, hospital stay length, body weight, other fractures, pleural effusion, pulmonary contusions, pneumothorax and occurrence of an anaesthetic event. A retrospective calculation of an animal trauma triage (ATT) score, RibScore and Modified RibScore was assigned. RESULTS: Forty-one medical records were collected. Motor vehicular trauma represented 56% of the rib fracture aetiology, 41% of patients sustained dog bites and one case was of an unknown aetiology. Significant correlations with risk factors were found only with the ATT score. All patients that died had an ATT score ≥ 5. The ATT score correlated positively with mortality (p < 0.05) with an ATT score ≥ 7 was 88% sensitive and 81% specific for predicting mortality. A 1-point increase in ATT score corresponded to 2.1 times decreased likelihood of survival. Mean hospital stay was 3 days longer for dog bite cases. CLINICAL SIGNIFICANCE: There was no increased mortality rate in canine patients that presented with the suspected risk factors. The only risk factor that predicted mortality was the ATT score.

[Surgical stabilization of multiple rib fractures can shorten inpatient stay].

Flail chest is a common complication in patients with blunt chest wall traumas resulting in high mortality rates. In this case report a 43-year-old woman was stepped on by a horse, thereby receiving multiple rib fractures and pneumohaemothorax. She was not able to wean from epidural analgesia after ten days and maintained a "thoracic floating feeling". In opposition to the non-operative management previously preferred, a surgical stabilization was then performed in the patient, who was discharged only five days later. Thus, surgical fixation of multiple rib fractures may reduce inpatient stay.