Position paper on fatal abusive head injuries in infants and young children

Forensic Pathologist Testimony, Part 1: Common Questions and Considerations

Introduction

Forensic pathologists are the only medical specialists who routinely testify in courts of law as part of their occupation. As such, one element of their training involves learning how to testify responsibly and competently. Individuals qualified as experts are permitted to offer opinions in order to assist the triers of fact.

Results

We review the forensic pathologist's primary role as an expert witness which is to lay out concepts clearly, methodically, and objectively, in medicine, pathophysiology, toxicology, and injury, to convey these concepts with understandable, plain language, and to explain how certain evidence, physical, medical, and historical, supports their conclusions and/or presents limitations.

Discussion

We discuss various components about testifying in court, some common expert questions posed to the forensic pathologist, and what concepts and facts they might consider when answering them. We do not offer a prescription as to how one should answer these questions specifically, but rather we provide a single resource that summarizes some of the key issues that may arise in court for the forensic pathologist.

An interdisciplinary forensic approach in a mummified child with evidence of abuse and neglect

Mummification of corpses with partial skeletonization is not an uncommon occurrence in daily forensic work. Cooperation between different forensic fields is important in these cases in terms of obtaining the most accurate and forensically relevant results, especially when child abuse and neglect is suspected. In Central Europe, up to 21% of children are exposed to physical and psychological harm, which is mostly perpetrated by family members. This report describes a case of subadult female mummified remains in which interdisciplinary forensic pathology, forensic anthropology, and entomology input was needed to obtain legally relevant results. Entomological analysis of the fly and beetle species present served primarily to estimate the postmortem interval. External examination confirmed advanced postmortem decomposition of the body. The anthropological findings based on radiographs and analysis of selected bones confirmed various antemortem fractures and post-traumatic changes involving the ribs, the distal portion of the humerus, the nasal bones, and the anterior portions of the maxilla and mandible. Furthermore, non-specific findings of growth arrest (Harris) lines in the distal metaphysis of the right tibia indicated growth retardation and, overall, child neglect. The autopsy findings confirmed subdural blood coagulum, part of which formed a clearly moulded plaster mass that had originally been attached to the cranial vault up to the internal lamina. The findings indicated a post-traumatic condition as the underlying cause of death in this child. Interdisciplinary forensic analyses confirmed that the child had been repeatedly exposed to violent assaults throughout her lifetime.

Key points

If mummified remains with partial skeletonization of a subadult are found, collaboration among forensic experts is requiredIn this case, dried subdural blood coagulum indicated post-traumatic, non-spontaneous subdural haemorrhagePeriosteal reaction present on the facial bones and distal portion of the humerus was a suspicious findingAnalyses of female subadult remains based on an interdisciplinary approach revealed a syndrome of child abuse and neglect.

Shear shock wave injury in vivo: High frame-rate ultrasound observation and histological assessment

Using high frame-rate ultrasound and ¡1μm sensitive motion tracking we previously showed that shear waves at the surface of ex vivo and in situ brains develop into shear shock waves deep inside the brain, with destructive local accelerations. However post-mortem tissue cannot develop injuries and has different viscoelastodynamic behavior from in vivo tissue. Here we present the ultrasonic measurement of the high-rate shear shock biomechanics in the in vivo porcine brain, and histological assessment of the resulting axonal pathology. A new biomechanical model of brain injury was developed consisting of a perforated mylar surface attached to the brain and vibrated using an electromechanical shaker. Using a custom sequence with 8 interleaved wide beam emissions, brain imaging and motion tracking were performed at 2900 images/s. Shear shock waves were observed for the first time in vivo wherein the shock acceleration was measured to be 2.6 times larger than the surface acceleration ( 95g vs. 36g). Histopathology showed axonal damage in the impacted side of the brain from the brain surface, accompanied by a local shock-front acceleration of >70g. This shows that axonal injury occurs deep in the brain even though the shear excitation was at the brain surface, and the acceleration measurements support the hypothesis that shear shock waves are responsible for deep traumatic brain injuries.

Difficulties Encountered by Forensic Pathologists in Proving Abusive Head Trauma in Children: A Case Report

Shaken baby syndrome (SBS) or abusive head trauma (AHT) is one of the most common causes of death or serious neurological injury resulting from child abuse. AHT is defined as injury to the skull or intracranial contents of an infant or child younger than five years due to intentional abrupt impact and/or violent shaking. It is characterized by acute encephalopathy with subdural and retinal hemorrhages. We present a case of AHT that does not show the typical clinical triad. We describe one case of a pediatric patient addressed for forensic autopsy and where suspicion of AHT has arisen. The injury mechanism involved in the production of this syndrome and its clinical manifestation are sources of debate in forensic medicine. Thus, forensic pathologists must analyze all findings to determine SBS/AHT.

Imaging of Abusive Head Trauma in Children

In this article, we describe relevant anatomy, mechanisms of injury, and imaging findings of abusive head trauma (AHT). We also briefly address certain mimics of AHT, controversies, pearls, and pitfalls. Concepts of injury, its evolution, and complex nature of certain cases are highlighted with the help of case vignettes.

Characterization of subdural collections in initial neuroimaging of abusive head trauma: Implications for forensic age diagnostics and clinical decision-making

PURPOSE

Subdural collections (SDCs) represent a key finding in abusive head trauma (AHT), a serious form of child physical abuse. Common SDC entities in this context are subdural hematoma (SDH), subdural hygroma (SDHy), subdural hematohygroma (SDHHy), and chronic subdural hematoma (cSDH). The present study examines the prevalence of the different SDC entities and investigates the influence of the SDC diagnosis on the forensic age estimation of the injury.

METHODS

In this retrospective multi-center study from three German university hospitals of a 10-year period, the initial neuroimaging material (CT or MRI) of 56 children (36 males, 20 females; age median 3.9 months) with medico-legally well-documented AHT was analyzed. SDCs were characterized by determining presence, location, extension, and visual appearance, by assigning to one of the five entities, and by categorizing with three different classification systems, one of which represents a novel system based on focality and Mixed Appearance Pattern and especially developed for children with AHT. The data were correlated with demographic and clinical data. By means of court files, AHT cases were also sub-divided into confession (n = 14) and non-confession cases (n = 42) and then compared.

RESULTS

Most cases showed a multifocal presence of SDCs (96.4%) and the presence of a Mixed Appearance Pattern (82.1%). The most common SDC entity was the heterogeneous variant of the SDHHy (66.1%). The cSDH occurred infrequently only (3.6%). Our novel classification system illustrates that unifocal SDCs rarely occur in AHT, and that more complex SDC patterns are common. In nearly all cases (94.6%), additional signs of recently caused brain injury were present beside the SDCs. Comparison between confession and non-confession groups did not reveal any significant differences, indicating that the diagnostic criteria of AHT are robust.

CONCLUSIONS

Although precise dating of SDCs based on initial neuroimaging alone remains unrealistic, the exact diagnosis of the SDC entity provide an important basis for differentiation between acute trauma and chronic post-traumatic state. Therefore, especially the confirmation or exclusion of subdural neomembranes, that define the cSDH, should be considered indispensable.

The Eyes Have It: How Critical are Ophthalmic Findings to the Diagnosis of Pediatric Abusive Head Trauma?

Pediatric abusive head trauma (AHT), still colloquially known as shaken baby syndrome, is a leading cause of morbidity and mortality among infants. Controversy has grown surrounding this diagnosis, and the specificity of the clinical findings-subdural hemorrhage, cerebral edema, and retinal hemorrhages-has been challenged. A literature search of peer reviewed publications on PubMed pertaining to the history, clinical, and pathologic features of AHT was conducted using the terms "shaken baby syndrome," "non-accidental trauma," "abusive head trauma," "inflicted traumatic brain injury," "shaken impact syndrome," and "whiplash shaken infant syndrome." Focus was placed on articles discussing ophthalmic findings in AHT. Retinal hemorrhages-particularly those that are too numerous to count, occurring in all layers of the retina (preretinal, intraretinal, subretinal), covering the peripheral pole and extending to the ora serrata, and accompanied by retinoschisis and other ocular/periocular hemorrhages-are highly suggestive of AHT, particularly in the absence of otherwise explained massive accidental trauma. Although the diagnosis has grown in controversy in recent years, AHT has well-documented clinical and pathologic findings across a large number of studies.

Neuropathology and Ophthalmological Pathology of Fatal Central Nervous System Injuries in Young Children: Forensic Neuropathology of Deaths of Children Under Age 2, 2008-2016, in Central Missouri

Nonaccidental head injuries are significant causes of morbidity and mortality among young children. Despite broad agreement among medical experts, controversies remain over diagnostic criteria, including from autopsies, because of opinions expressed by a small group of expert witnesses who testify for defendants in suspected child homicide cases. We reviewed 249 autopsies in children 2 years old and younger from the files of our Medical Examiner office in the University of Missouri School of Medicine done between January 1, 2008 and December, 31, 2016. Because of gradually instituted mandatory examination of spinal cords and retinas, we had 127 autopsies with brain examinations by a neuropathologist plus retinal examinations of which 67 also had spinal cord examinations. Results were correlated with clinical records, police and EMS reports, and imaging. We found that subdural hematomas, cerebral edema, and retinal hemorrhages were mostly limited to autopsy findings in children who suffered from fatal head trauma, whether accidental (3 cases) or inflicted (14); they were not encountered in cases of homicide by other mechanisms or from natural diseases including infections, brain tumors, SIDS/SUID, or SUDC. Two cases with no other evidence of head trauma had focal retinal hemorrhages. We advocate for examination of retinas and spinal cords in all autopsies of children in this age group.

Comparative study of brain damage and oxidative stress using two animal models of the shaken baby syndrome

The objective was compare the morphological damages in brain and to evaluate the participation of oxidative stress, using two animal models of shaken baby syndrome (SBS). Five-day-old Wistar rats were used to develop two models of SBS as follows: Gyrotwister (GT) group was subjected to low intensity, high duration rotating movements and Ratshaker (RS) group made to undergo high intensity, low duration anteroposterior movements. Both groups presented respiratory distress, weight loss and shorter stature compared with the control group. In addition, involuntary movements occurred in both experimental models. Hemorrhage was observed in 10 % of the GT group and in 40 % of the RS group. This last group experienced lesser weight gain at 30 days. Glutathione decreased by 25.7 % (GT) and 59.96 (RT). Cell data analysis revealed the presence of crenate and pyknotic cells, characterized by apparent absence of nucleus and nucleolus as well as vacuolation in the GT group. In the RS group, there were a high number of angular, pyknotic and shrunken cells, and a lot of vacuolization. The severity of the brain damage can be related to the magnitude of biochemical modifications, specifically, those related to the production of reactive oxygen or nitrogen species, oxidative stress, oxidative damage.

Imaging of Abusive Head Trauma : A Radiologists' Perspective

Abusive head trauma (AHT) is the most common and serious form of child abuse and a leading cause of traumatic death in infants and young children. The biomechanics of head injuries include violent shaking, blunt impact, or a combination of both. Neuroimaging plays an important role in recognizing and distinguishing abusive injuries from lesions from accidental trauma or other causes, because clinical presentation and medical history are often nonspecific and ambiguous in this age group. Understanding common imaging features of AHT can increase recognition with high specificity for AHT. In this review, we discuss the biomechanics of AHT, imaging features of AHT, and other conditions that mimic AHT.

Fractures and skin lesions in pediatric abusive head trauma: a forensic multi-center study

Abusive head trauma (AHT) and its most common variant, the shaken baby syndrome (SBS), are predominantly characterized by central nervous system-associated lesions. Relatively little data are available on the value of skeletal and skin injuries for the diagnosis of SBS or AHT. Thus, the present study retrospectively investigated 72 cases of living children diagnosed with the explicit diagnosis of SBS during medico-legal examinations at three German university institutes of legal medicine. The risk of circular reasoning was reduced by the presence of 15 cases with confession by perpetrators. Accordingly, the comparison with the 57 non-confession cases yielded no significant differences. Skeletal survey by conventional projection radiography, often incomplete, was found to be performed in 78% of the cases only. Fractures were found in 32% of the cases. The skull (43%) and ribs (48%) were affected most frequently; only 8% of the cases showed classic metaphyseal lesions. In 48% of the cases, healing fractures were present. Skin lesions (hematomas and abrasions) were found in 53% of the cases with the face (76%), scalp (26%), and trunk (50%) being the major sites. In 48% of the cases, healing skin lesions were observed. Nearly 80% of the cases with fractures also showed skin lesions. The data prove that SBS is frequently accompanied by other forms of physical abuse. Therefore, skeletal survey is indispensable and should always be done completely and according to existing imaging guidelines if child abuse is suspected.

Abusive head trauma in India: imaging raises the curtain

The purpose of the study was to identify children at our institute who possibly suffered abusive head trauma (AHT). A retrospective study of CT imaging of children between one month to three years of age between January 2013 and May 2021 was carried out at a dedicated neurocentre in Southern India. We identified 48 cases of possible AHT. The demographics, clinical features at presentation, imaging and fundus findings were analyzed. Imaging revealed subdural hemorrhage (SDH) in 42 and sub dural effusion (SDE) in 5 cases, one case had only hypoxia. The location of SDH was studied as was hypoxia underlying SDH, global hypoxia and ischemia. Cases of subarachnoid hemorrhage (SAH), parenchymal hematoma & intraventricular hemorrhage (IVH) were also noted. Skeletal survey, chest X-ray and CT spine were reviewed. AHT needs to be paid attention to in the Indian scenario. An extensive work up is required to substantiate the claim and to work on prevention & management of these cases subsequently.

Thrombosis is not a marker of bridging vein rupture in infants with alleged abusive head trauma

Aim

Thrombosis of bridging veins has been suggested to be a marker of bridging vein rupture, and thus AHT, in infants with subdural haematoma.

Methods

This is a non‐systematic review based on Pubmed search, secondary reference tracking and authors’ own article collections.

Results

Radiological studies asserting that imaging signs of cortical vein thrombosis were indicative of traumatic bridging vein rupture were unreliable as they lacked pathological verification of either thrombosis or rupture, and paid little regard to medical conditions other than trauma. Autopsy attempts at confirmation of ruptured bridging veins as the origin of SDH were fraught with difficulty. Moreover, microscopic anatomy demonstrated alternative non‐traumatic sources of a clot in or around bridging veins. Objective pathological observations did not support the hypothesis that a radiological finding of bridging vein thrombosis was the result of traumatic rupture by AHT. No biomechanical models have produced reliable and reproducible data to demonstrate that shaking alone can be a cause of bridging vein rupture.

Conclusion

There is no conclusive evidence supporting the hypothesis that diagnostic imaging showing thrombosed bridging veins in infants correlates with bridging vein rupture. Hence, there is no literature support for the use of thrombosis as a marker for AHT.

Shaken Baby Syndrome: Magnetic Resonance Imaging Features in Abusive Head Trauma

In the context of child abuse spectrum, abusive head trauma (AHT) represents the leading cause of fatal head injuries in children less than 2 years of age. Immature brain is characterized by high water content, partially myelinated neurons, and prominent subarachnoid space, thus being susceptible of devastating damage as consequence of acceleration-deceleration and rotational forces developed by violent shaking mechanism. Diagnosis of AHT is not straightforward and represents a medical, forensic, and social challenge, based on a multidisciplinary approach. Beside a detailed anamnesis, neuroimaging is essential to identify signs suggestive of AHT, often in absence of external detectable lesions. Magnetic resonance imaging (MRI) represents the radiation-free modality of choice to investigate the most typical findings in AHT, such as subdural hematoma, retinal hemorrhage, and hypoxic-ischemic damage and it also allows to detect more subtle signs as parenchymal lacerations, cranio-cervical junction, and spinal injuries. This paper is intended to review the main MRI findings of AHT in the central nervous system of infants, with a specific focus on both hemorrhagic and non-hemorrhagic injuries caused by the pathological mechanisms of shaking. Furthermore, this review provides a brief overview about the most appropriate and feasible MRI protocol to help neuroradiologists identifying AHT in clinical practice.

[Bridging vein injuries in shaken baby syndrome : Forensic-radiological meta-analysis with special focus on the tadpole sign]

Shaken baby syndrome is a common variant of the abusive head trauma in infants and toddlers and is still subject of intensive research. In recent years, a number of radiological studies on the diagnostic and forensic relevance of injured bridging veins were conducted using different imaging modalities. The present article will give an overview on the current state of research in this field and will discuss the forensic implications. The meta-analysis of the seven currently existing studies revealed that injuries of the bridging veins and bridging vein thromboses, respectively, frequently appear as rounded, enlarged, and/or tubular structures. The "tadpole sign" may serve as a valuable tool for the identification of these formations. Especially, T2*/SWI (susceptibility-weighted imaging) sequences allow for good detectability of these lesions and should always be generated when abusive head trauma is suspected. In conclusion, it can be recommended that the presence of radiologically detectable bridging vein injuries should give reason to search for other manifestations of physical child abuse.

Abusive head trauma in court: a multi-center study on criminal proceedings in Germany

The shaken baby syndrome (SBS) is a common variant of abusive head trauma (AHT) in infants and toddlers. Data on the legal outcome of such cases are still sparse. By means of a retrospective multi-center analysis, 72 cases of living children diagnosed with SBS/AHT from three German university institutes of legal medicine were identified. Forty-six of these cases with 68 accused individuals were available and could be evaluated with regard to basic data on the course of the criminal proceedings as well as the profile of the defendants (sub-divided into suspects, convicts, and confessed perpetrators). Criminal proceedings predominantly commenced with a complaint by the treating hospital (62%) and were found to be closed (without judgment) in 50% of the cases, mostly due to a "lack of sufficient suspicion." Of the 23 cases with judgment, the court decided on acquittal in 4 cases (17%). Imprisonment was the most frequent sentence (16 out of 19 cases with conviction, 84%), whereby the sentence has been suspended on probation in 63% of the cases. Suspects and perpetrators were mostly male and derived from the close family environment of the injured children. All confessed perpetrators stated an "excessive demand" as the reason for the violent shaking of the child. The results of the present study are in line with data from other studies with other legal systems. As many criminal proceedings were closed and the 4 acquittals occurred because the perpetration could not be ascribed to a specific perpetrator, improving the forensic methods for such an unequivocal assignment would be desirable.

Critical Appraisal of Traumatic Brain Injury and Its Management

Critical appraisal of traumatic brain injury (TBI) management has always been marred with a conflict of differential approaches, with claims and counterclaims of outcomes among the research groups. We performed this study to review the management of TBI from risk factors to outcomes including the comorbidities and final clinical status. In conjunction with the aforesaid stabilization of TBI cases, prophylactic and definitive surgical approaches and other supporting interventions will ultimately decide the final outcomes in the long run. Improvements in the quality of care for patients with severe TBI, with the reduction in mortality, have been demonstrated in high-income areas due to improvements in the health care system and not just in one isolated intervention. In the management of TBI, a fast and high index of suspicion is the key to success, from the initial assessment to the final rehabilitation of the cases, from the victim of risk factors to the victims of situation. The research groups feel that TBI prophylactic measures and primary care mitigation models are as important as definitive care, starting from prehospital care to dedicated care.

The neuroimaging magnitude of pediatric brain atrophy in northern Tanzania

Introduction

The loss of parenchymal brain volume per normative age comparison is a distinctive feature of brain atrophy. While the condition is the most prevalent to elderly, it has also been observed in pediatric ages. Various causes such as trauma, infection, and malnutrition have been reported to trigger the loss of brain tissues volume. Despite this literature based knowledge of risk factors, the magnitude of brain atrophy in pediatric age group is scantly addressed in most developing countries including Tanzania. The current study aims to understand the magnitude of brain atrophy in children residing in Northern Zone, Tanzania.

Methods

A cross-sectional hospital survey was performed in which 455 children who were presented with various brain pathologies from the year 2013 to 2019 and whose brains examined by Computerized tomography (CT)-Scanners were recruited in the study. The brain statuses were examined using three linear radiological methods including the measure of sulcal-width, Evans index, and lateral ventricular body width.

Results

Results showed a significant number of atrophied brains among children in Northern Tanzania and that the condition was observed to have a 1:1 male to female ratio. The prevalence of pediatric brain atrophy was found to be 16.04%.

Conclusion

The cortical subtype of brain atrophy presented as the most prevalent type of brain volume loss. The findings of this study suggest existence of considerable trends of brain atrophy in children which need special attention and mitigation plans.

Understanding Subdural Collections in Pediatric Abusive Head Trauma

Life-threatening physical abuse of infants and toddlers is frequently correlated with head injuries. A common variant of the abusive head trauma is the shaken baby syndrome. The present review article sheds light on subdural collections in children with abusive head trauma and aims at providing a recent knowledge base for various medical disciplines involved in diagnostic procedures and legal proceedings. To this end, the different subdural collection entities are presented and illustrated. The pathophysiologic background is explained. Differential and age-diagnostic aspects are discussed and summarized by tabular and graphic overviews. Two problematic constellations frequently occurring during initial CT investigations are evaluated: A mixed-density subdural collection does not prove repeated trauma, and hypodense subdural collections are not synonymous with chronicity. The neuroradiologic analysis and assessment of subdural collections may decisively contribute to answering differential diagnostic and forensic questions. In addition to more reference data, a harmonization of terminology and methodology is urgently needed, especially with respect to age-diagnostic aspects.

Non-Traumatic Acute Subdural Hemorrhage Due To Cranial Venous Hypertension

Acute subdural hemorrhage is typically associated with a history of head trauma, and as such it is a finding with significant potential medicolegal consequences. In this article, 37 adult and post-infantile pediatric sudden death autopsy cases with small volume ("thin film" or "smear") acute subdural hemorrhage are presented-in which there is either no further evidence of head trauma or only features of minor head injury. The possible underlying pathophysiological mechanisms are explored, and it is concluded that a common thread in many of these cases is likely to have been cranial venous hypertension at around the time of death. These findings may have implications in instances where small volume subdural hemorrhage is identified in the absence of other evidence of significant head injury.

Childhood Falls With Occipital Impacts

OBJECTIVES

Falls are commonly reported in children who present with both accidental and inflicted brain injuries. Short falls rarely result in serious or life-threatening injuries. Our purpose is to describe a series of cases of short falls with occipital impact leading to subdural hemorrhage (SDH).

METHODS

We present a series of 8 witnessed accounts of young children diagnosed as having SDHs after striking the back of their heads during a short fall. Child-abuse physicians were surveyed to determine if they had evaluated a child younger than 24 months diagnosed as having SDH, with or without retinal hemorrhages, following a witnessed fall with occipital impact. Submitted cases were analyzed.

RESULTS

The median age of the children was 12.5 months. All fell backward from a standing or seated position onto a hard surface and immediately developed symptoms. There was an average of 4 witnesses per case. Physical examinations were normal; however, the majority of children had enlarged head circumferences. All were previously healthy. Six of 8 children had unilateral convexity SDH. All children had varying degrees of retinal hemorrhage but no retinoschisis. The majority of children had returned to their baseline within 24 hours of hospitalization.

CONCLUSIONS

Although a larger study is needed to identify the full spectrum of injuries, we postulate that, if a history of a fall with an occipital impact is elicited during a trauma workup, accidental injury should be considered.

Comparing disciplinary methods used by mothers in Palestine and Qatar

This paper explores child disciplinary methods used by parents in Qatar and Palestine. In this study ICAST-P, an internationally recognized tool, was used with mothers reporting on one of their children up to their 12th birthday. It questions about disciplinary methods: nonviolent; physical: moderate and severe; and psychological methods that had been used in the previous year on the index child in the family. A comparative national cross-sectional household survey of mothers aged 25-50 years old was conducted in both Qatar and Palestine, both Arabic Muslim states, but with very different socio-economic and political contexts that place Qataris in a much more advantageous position. Our results show that the 1299 Palestinian mothers interviewed were younger, had more children and less education compared to the 1018 Qatari mothers. Fewer mothers from Palestine were working. The index child in Palestine tended to be younger with 60% being under 5 years, while 73.7% of Qatari children were over 5 years of age. Severe physical disciplinary methods were reported significantly more often, in Palestine, e.g. Kicking the child (P value < 0.001), using hand or pillow to prevent breathing (P value < 0.001) and hitting child with object or fist (P value < 0001). Moderate as well as psychological disciplinary methods were also significantly higher among Palestinian mothers (P value < 0.001). Our results suggest that challenging circumstances that Palestinian mothers experience, as compared to their Qatari peers, are associated with greater prevalence of the harsher forms of discipline. Our findings have policy implications and preventative strategies for child maltreatment in both countries.

Neonatal subcortical bruising

A specific type of acute brain injury can occur during birth, presenting on ultrasound examination with focal, unilateral, or asymmetrical change in the core of the superior frontal gyri. Ultrasound inspection of the superior gyri near the convexity of the frontal lobe is warranted following mechanically difficult delivery.

Biomechanical Studies on Patterns of Cranial Bone Fracture Using the Immature Porcine Model

This review was prepared for the American Society of Mechanical Engineers Lissner Medal. It specifically discusses research performed in the Orthopaedic Biomechanics Laboratories on pediatric cranial bone mechanics and patterns of fracture in collaboration with the Forensic Anthropology Laboratory at Michigan State University. Cranial fractures are often an important element seen by forensic anthropologists during the investigation of pediatric trauma cases litigated in courts. While forensic anthropologists and forensic biomechanists are often called on to testify in these cases, there is little basic science developed in support of their testimony. The following is a review of studies conducted in the above laboratories and supported by the National Institute of Justice to begin an understanding of the mechanics and patterns of pediatric cranial bone fracture. With the lack of human pediatric specimens, the studies utilize an immature porcine model. Because much case evidence involves cranial bone fracture, the studies described below focus on determining input loading based on the resultant bone fracture pattern. The studies involve impact to the parietal bone, the most often fractured cranial bone, and begin with experiments on entrapped heads, progressing to those involving free-falling heads. The studies involve head drops onto different types and shapes of interfaces with variations of impact energy. The studies show linear fractures initiating from sutural boundaries, away from the impact site, for flat surface impacts, in contrast to depressed fractures for more focal impacts. The results have been incorporated into a “Fracture Printing Interface (FPI),” using machine learning and pattern recognition algorithms. The interface has been used to help interpret mechanisms of injury in pediatric death cases collected from medical examiner offices. The ultimate aim of this program of study is to develop a “Human Fracture Printing Interface” that can be used by forensic investigators in determining mechanisms of pediatric cranial bone fracture.

Biomechanical Response of the Infant Head to Shaking: An Experimental Investigation

Controversy exists regarding whether violent shaking is harmful to infants in the absence of impact. In this study, our objective was to characterize the biomechanical response of the infant head during shaking through use of an instrumented anthropomorphic test device (commonly referred to as a "crash test dummy" or surrogate) representing a human infant and having improved biofidelity. A series of tests were conducted to simulate violent shaking of an infant surrogate. The Aprica 2.5 infant surrogate represented a 5th percentile Japanese newborn. A 50th percentile Japanese adult male was recruited to shake the infant surrogate in the sagittal plane. Triaxial linear accelerometers positioned at the center of mass and apex of the head recorded accelerations during shaking. Five shaking test series, each 3-4 sec in duration, were conducted. Outcome measures derived from accelerometer recordings were examined for trends. Head/neck kinematics were characterized during shaking events; mean peak neck flexion was 1.98 radians (113 degrees) and mean peak neck extension was 2.16 radians (123 degrees). The maximum angular acceleration across all test series was 13,260 radians/sec² (during chin-to-chest contact). Peak angular velocity was 105.7 radians/sec (during chin-to-chest contact). Acceleration pulse durations ranged from 72.1 to 168.2 ms. Using an infant surrogate with improved biofidelity, we found higher angular acceleration and higher angular velocity than previously reported during infant surrogate shaking experiments. Findings highlight the importance of surrogate biofidelity when investigating shaking.

A Conceptual Overview of Axonopathy in Infants and Children with Allegedly Inflicted Head Trauma

Fatal, allegedly inflicted pediatric head trauma remains a controversial topic in forensic pathology. Recommendations for systematic neuropathologic evaluation of the brains of supposedly injured infants and children usually include the assessment of long white matter tracts in search of axonopathy - specifically, diffuse axonal injury. The ability to recognize, document, and interpret injuries to axons has significant academic and medicolegal implications. For example, more than two decades of inconsistent nosology have resulted in confusion about the definition of diffuse axonal injury between various medical disciplines including radiology, neurosurgery, pediatrics, neuropathology, and forensic pathology. Furthermore, in the pediatric setting, acceptance that "pure" shaking can cause axonal shearing in infants and young children is not widespread. Additionally, controversy abounds whether or not axonal trauma can be identified within regions of white matter ischemia - a debate with very significant implications. Immunohistochemistry is often used not only to document axonal injury, but also to estimate the time since injury. As a result, the estimated post-injury interval may then be used by law enforcement officers and prosecutors to narrow "exclusive opportunity" and thus, identify potential suspects. Fundamental to these highly complicated and controversial topics is a philosophical understanding of the diffuse axonal injury spectrum disorders.

Infants dying suddenly and unexpectedly share demographic features with infants who die with retinal and dural bleeding: a review of neural mechanisms

The cause of death in infants who die suddenly and unexpectedly (sudden unexpected death in infancy [SUDI]) remains a diagnostic challenge. Some infants have identified diseases (explained SUDI); those without explanation are called sudden infant death syndrome (SIDS). Demographic data indicate subgroups among SUDI and SIDS cases, such as unsafe sleeping and apparent life-threatening events. Infants dying suddenly with retinal and dural bleeding are often classified as abused, but in many there is no evidence of trauma. Demographic features suggest that they may represent a further subgroup of SUDI. This review examines the neuropathological hypotheses to explain SIDS and highlights the interaction of infant oxygen-conserving reflexes with the brainstem networks considered responsible for SIDS. We consider sex- and age-specific vulnerabilities related to dural bleeding and how sensitization of the dural innervation by bleeding may influence these reflexes, potentially leading to collapse or even death after otherwise trivial insults.

Deaths Due to Child Abuse: A 6-Year Review of Cases in The Cook County Medical Examiner's Office

Case files from the Cook County Medical Examiner's Office from 2007 to 2012 were reviewed to analyze homicides due to physical child abuse in children <3 years old. Fatal cases mostly involved younger subjects. Intracranial injuries were the leading cause of death, while death due to extracranial injuries was uncommon. Eyes were involved in most of the cases. Spinal cord was involved in about 1/3 of the cases, mostly in the thoracic area. In some cases, previous injuries were present. There were significant differences in the pattern of injuries between age groups. Subjects showing signs of impact to the head and subjects with no evidence of an impact showed no significant difference in internal injuries. The association of multiple injuries is highly suggestive of child abuse. In suspected child abuse, a postmortem examination including neuropathological, ophthalmological, and radiological information should be always evaluated, together with investigative reports and the medical history.

The impact of an educational intervention on knowledge about infant crying and abusive head trauma

BACKGROUND

Infants follow a predictable trajectory of increased early crying. Frustration with crying is reported to be a trigger for abusive head trauma (AHT).

OBJECTIVE

To evaluate the impact of postpartum delivery of the educational program, the Period of PURPLE Crying (PURPLE), in a group of first-time mothers. The primary objective was to determine whether there was a change in knowledge about infant crying and shaking after exposure to PURPLE. Factors associated with change in knowledge were also examined.

METHOD

A total of 93 participants were recruited over a four-month period at a tertiary care hospital in Nova Scotia. Pre- and postintervention data were collected.

RESULTS

Knowledge about infant crying increased significantly after program delivery (P=0.001). Low baseline crying knowledge was a significant predictor of increased knowledge about infant crying (P≤0.01). There was an insignificant decrease in shaking knowledge (P=0.5), which may have been the consequence of high baseline knowledge.

CONCLUSION

An educational program for new parents appears to be warranted, especially with respect to improving knowledge about infant crying. This may have a positive benefit in AHT prevention. Additional studies are required to evaluate the impact of the program on other caregivers and on rates of AHT.

An evidence-based method for targeting an abusive head trauma prevention media campaign and its evaluation

BACKGROUND

A triple-dose abusive head trauma (AHT) prevention program (Period of PURPLE Crying) was implemented. The third dose consisted of an education media campaign. The study objectives were to describe the qualitative and spatial methods developed to target AHT prevention and to evaluate this campaign.

METHODS

A questionnaire on the level of importance of factors, rated on a 7-point Likert scale, was distributed to a panel of experts to determine the best advertising locations. Ranked factors were used to create weights for statistical modeling and mapping within a Geographic Information Systems to determine optimal ad locations. The media campaign was evaluated via a telephone survey of randomly selected households.

RESULTS

The survey found locations of new families, high population density, and high percentage of lone parents to be the most important factors for selecting billboard sites. Spatial analysis revealed six areas that ranked highest in our factors. Five billboards, four media posters, and six transit shelters were selected for our advertisements. A population-based telephone survey revealed that 23% of respondents knew the campaign. Nearly half (42%) heard the radio public service announcements, and 9% saw billboards.

CONCLUSION

Extending primary prevention efforts to the public helps to create a cultural change in the way inconsolable crying, the trigger for AHT, is viewed. With the use of ranked factors and Geographic Information Systems, geographic locations with high visibility and specific risk factors for AHT were identified for targeting the campaign, facilitating the likelihood that our message was reaching the population in greatest need.

Avaliação do Conhecimento sobre Trauma Craniano Violento por Pais Brasileiros

RESUMO A ocorrência do trauma craniano violento (TCV) pode estar associada à falta de conhecimento de pais e cuidadores sobre o desenvolvimento infantil. Neste sentido, o presente estudo pretendeu investigar o conhecimento de pais sobre o choro do bebê, as estratégias para lidar com o choro e as consequências de sacudi-lo. Participaram da pesquisa 83 mães e 7 pais de recém-nascidos, que responderam ao instrumento Questionário sobre o Choro do Bebê. Os resultados do estudo sugerem um desconhecimento por parte dos pais sobre o TCV, principalmente no que se refere à sua gravidade. Além disso, 34,4% dos participantes relataram que sacudiriam seus bebês para fazê-los parar de chorar. Tais resultados parecem indicar a necessidade de desenvolver intervenções de educação parental sobre o TCV, especialmente durante o pré-natal, de modo a contribuir para o aumento do conhecimento dos pais, prevenindo assim tal forma de maus-tratos.

Revisiting neuroimaging of abusive head trauma in infants and young children

OBJECTIVE

The purpose of this article is to use a mechanism-based approach to review the neuroimaging findings of abusive head trauma to infants. Advanced neuroimaging provides insights into not only the underlying mechanisms of craniocerebral injuries but also the long-term prognosis of brain injury for children on whom these injuries have been inflicted.

CONCLUSION

Knowledge of the traumatic mechanisms, the key neuroimaging findings, and the implications of functional imaging findings should help radiologists characterize the underlying causes of the injuries inflicted, thereby facilitating effective treatment.

Controversies in pediatric forensic pathology

Pediatric forensic pathology is an emerging medical subspecialty that spans the area between pediatric and forensic pathology. Advances in both of these fields have increased the sophistication of diagnoses, with overlap of disorders that might present to either the pediatric or forensic pathologist, adding further layers of complexity. Not surprisingly, therefore, there are important ethical and medical controversies in pediatric forensic pathology that merit careful consideration and attention.

Imaging abusive head trauma: why use both computed tomography and magnetic resonance imaging?

Abusive head trauma is the leading cause of death in child abuse cases. The majority of victims are infants younger than 1 year old, with the average age between 3 and 8 months, although these injuries can be seen in children up to 5 years old. Many victims have a history of previous abuse and the diagnosis is frequently delayed. Neuroimaging is often crucial for establishing the diagnosis of abusive head trauma as it detects occult injury in 37% of cases. Several imaging patterns are considered to be particularly associated with abusive head trauma. The presence of subdural hematoma, especially in multiple locations, such as the interhemispheric region, over the convexity and in the posterior fossa, is significantly associated with abusive head trauma. Although CT is the recommended first-line imaging modality for suspected abusive head trauma, early MRI is increasingly used alongside CT because it provides a better estimation of shear injuries, hypoxic-ischemic insult and the timing of lesions. This article presents a review of the use and clinical indications of the most pertinent neuroimaging modalities for the diagnosis of abusive head trauma, emphasizing the newer and more sensitive techniques that may be useful to better characterize the nature and evolution of the injury.

Distinguishing accidental from inflicted head trauma at autopsy

This article will discuss accidental and inflicted head injuries in infants and young children and how forensic pathologists distinguish between these types of injuries. The article begins with a consideration of the special and unique features of the anatomy and development of the child's head and neck and then relates these features to the mechanisms of traumatic brain injury and how these unique features influence the mechanisms of injury. The article very specifically notes that accidental head injuries in young children that occur in and around the home are focal head injuries in distinction to inflicted head injuries, which are diffuse brain injuries. The article discusses the mechanisms by which traumatic brain injury causes loss of consciousness and relates those mechanisms to the differences in the clinical features that occur in both accidental and inflicted head injury. The article discusses and illustrates the pathological findings in accidental head injuries consisting of the crushing head injuries and the head injuries sustained in short falls including epidural hemorrhage and focal subdural hemorrhage. The article discusses and illustrates the pathological findings that occur in inflicted head trauma, including subdural and subarachnoid hemorrhages and retinal and optic nerve sheath hemorrhages.

Visualisation of the intact dura mater and brain surface in infant autopsies: a minimally destructive technique for the post-mortem assessment of head injury

During the post-mortem examination of babies and young children, it is important to be able to visualise the brain and its coverings, particularly in cases where a head injury is likely to have occurred. In this paper, we present an improved method for removal of the calvarial bones in infant autopsies to enable viewing of the dura mater and brain. In contrast to the standard post-mortem procedure for observing and removing the brain, this novel technique is minimally disruptive, allowing the dura mater to remain undamaged. Specialised paediatric neurosurgical tools were used to remove the skull bones from 23 neonates, infants and young children during post-mortem examination. In 21 of our 23 cases, the calvarial bones were removed successfully with the dura mater remaining intact. In one case, there was a thickening of the dura mater which created a strong adherence of this membrane to the bone. In another case, the dura mater was slightly damaged due to the inexperience of the operator in using the neurosurgical tools. This method of calvarial bone removal reduces the degree of post-mortem artefact and enhances the ability to observe and photographically document autopsy findings, including the artefact-free detection of signs of injury such as epidural or subdural haematoma, and brain swelling. This technique has now become a routine practise in both of our units to remove the skull bones in infant/young children post-mortem examinations.

Factors associated with hemispheric hypodensity after subdural hematoma following abusive head trauma in children

Abusive head trauma (AHT) is a unique form of pediatric TBI with increased mortality and neurologic sequelae. Hemispheric hypodensity (HH) in association with subdural blood after AHT has been described. Though risk factors for HH are not understood, we hypothesized that risk factors could be identified. We retrospectively enrolled children under 5 years with TBI secondary to AHT (child advocacy diagnosis) who had undergone initial and interval brain imaging. Records were interrogated for prearrival and in-hospital physiologic and radiographic findings. HH was determined by a blinded observer. Twenty-four children were enrolled and 13 developed HH. HH was not significantly associated with age, initial Glascow Coma Scale, or mortality. Pediatric Intensity Level of Therapy (PILOT) scores (p=0.01) and daily maximal intracranial pressure (ICPmax; p=0.037) were higher in HH. Hypoxia, hypotension, cardiopulmonary arrest, need for blood transfusion, and daily blood glucoses tended to be greater in HH. Whereas all children with HH had acute subdural hematoma (SBH), many children without HH also had subdural blood; the presence of skull fracture was more likely in the children who did not develop HH (p=0.04), but no other intracranial radiographic pattern of injury was associated with HH. Surgical intervention did not appear to protect against development of HH. A variety of insults associated with ischemia, including intracranial hypertension, ICP-directed therapies, hypoxia, hypotension, and cardiac arrest, occurred in the children who developed HH. Given the morbidity and mortality of this condition, larger studies to identify mechanisms leading to the development of HH and mitigating clinical approaches are warranted.