Analysis of fatal injuries to motorcyclists by helmet type

To clarify the characteristics of injuries of motorcyclists dying in accidents in relation to helmet type, we retrospectively analyzed forensic autopsies of 36 helmeted motorcycle riders. The presence of major injuries and injury severity were evaluated with the injury severity score and the 1990 revision of the Abbreviated Injury Scale. Persons with open-face helmets (19 cases) were significantly more likely to have sustained severe head and neck injuries, especially brain contusions, than were persons with full-face helmets (17 cases). Furthermore, major injuries of the chest or abdomen, rib fractures, lung injuries, and liver injuries were each present in more than one quarter of all cases (26.3% to 70.6%), but their prevalences did not differ significantly between riders with different types of helmet. Because many types of head and neck injuries cannot be prevented and fatal chest and abdominal injuries occur despite the use of full-face helmets, more effective helmets and devices for protecting the chest and abdomen are needed to decrease deaths from motorcycle accidents.     

Pontomedullary lacerations in unhelmeted motorcyclists and bicyclists: a retrospective autopsy study

ABSTRACT: Pontomedullary lacerations (PMLs) have often been reported in car occupants and pedestrians, are less frequently described in motorcyclists, and are very rarely described in bicyclists. The aim of this study was to determine the frequency of brainstem PMLs among fatally injured motorcyclists and bicyclists as well as the frequency of concomitant cranial, facial, and cervical spine injuries in such cases. A possible underlying mechanism of PML in fatally injured motorcyclists and bicyclists might thus be established. Of 443 cases of fatally injured motorcyclists and bicyclists, a sample of 381 cases of fatally injured motorcyclists and bicyclists with head injury of Abbreviated Injury Scale score of 3 or greater was formed and further analyzed. This group was composed of 345 men and 36 women. The average age was 48.8 ± 20.8 years (range, 15-99 years). In the analyzed sample group, there were 158 motorcyclists and 223 bicyclists. Partial PMLs were present in 44 cases (12%) within the sample of 381 head injuries, which breaks down to 40 men and 4 women. In our study, the impact area on the head and the specific skull base fracture type were good predictors of either PML occurrence or absence (B = -2.036, Wald = 161.312, P < 0.01, for the whole model). Impact to the chin, with or without a skull base fracture, most often led to this fatal injury due to impact force transmission, either through jawbone or vertebral column. Also, lateral head impact, the most frequent in bicyclists, with subsequent hinge fracture, PML, and frontoposterior hyperextension of the head that is associated with upper spine fracture, could be possible mechanisms of brainstem injury in fatally injured motorcyclists or bicyclists. Our study showed that the jawbone, as well as other facial bones, could act as shock absorbers, and their fracture could diminish energy transfer toward the skull and protect the brain and brainstem from injury.     

Traumatic bilateral vertebral artery dissection

Traumatic vertebral artery dissection is not often seen by forensic pathologists, and cases investigated are scarce in the forensic literature. We present the case of a 40-year-old woman cyclist who was struck by a car while wearing a helmet, and was neurologically near normal immediately thereafter at Emergency. She presented 48 h later with acute right hemiparesis, decreasing level of consciousness, and unsteadiness. CT revealed massive cerebellar infarction. CT angiography was normal. The patient died in coma 7 days after injury and autopsy revealed bilateral edematous cerebellar infarction and bilateral vertebral artery dissection. Rotational neck injury and mural tear in the wall of the Atlantic parts of both vertebral arteries is suggested as the possible mechanism of the arterial injury. Head and neck injuries are reported as a precipitating cause of vertebral artery injury. The possible influence of trauma may be further underestimated if longer intervals between vessel dissection and ischemia occur. The current case illustrates that "talk-and-die" syndrome may be due to occult vertebral artery dissection, possibly bilateral. In forensic cases of delayed death after mild trauma to the head and neck, the vertebral arteries should be examined for the cause of death.     

Injuries of the Head from Backface Deformation of Ballistic Protective Helmets Under Ballistic Impact

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed “behind armor blunt trauma” (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400–460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear.     

Injury analyses of fatal motorcycle collisions in south-east Scotland

The timing of death and pathological findings in fatal motorcycle accidents in south-east Scotland between 1987 and 1997 were investigated. Of the 59 motorcyclists who died, 38 were dead when found at the accident scene, six others were alive when found but died at the scene, two died in an ambulance in transit to hospital and 13 died after reaching hospital. Scoring of the injuries according to the Abbreviated Injury Scale revealed Injury Severity Scores (ISS) ranging from 25 to 75. Overall, injuries to the head, neck and chest were responsible for the most severe injuries. Twenty-five motorcyclists had injuries acknowledged to be unsurvivable (ISS = 75), most of which involved the thoracic aorta, brainstem and cervical spinal cord. The greatest potential to reduce the death rate amongst motorcyclists lies with accident prevention/injury reduction measures, rather than through improved treatment of injuries. Efforts to try to alter driving behaviour and to improve the design of vehicles and helmets need to continue.     

Postmortem Computed Tomography in Firearm Homicides: A Retrospective Case Series,

Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.     

New horizons in forensic radiology: the 60-second digital autopsy-full-body examination of a gunshot victim by multislice computed tomography

The goal of this study was the full-body documentation of a gunshot wound victim with multislice helical computed tomography for subsequent comparison with the findings of the standard forensic autopsy. Complete volume data of the head, neck, and trunk were acquired by use of two acquisitions of less than 1 minute of total scanning time. Subsequent two-dimensional multiplanar reformations and three-dimensional shaded surface display reconstructions helped document the gunshot-created skull fractures and brain injuries, including the wound track, and the intracerebral bone fragments. Computed tomography also demonstrated intracardiac air embolism and pulmonary aspiration of blood resulting from bullet wound-related trauma. The "digital autopsy," even when postprocessing time was added, was more rapid than the classic forensic autopsy and, based on the nondestructive approach, offered certain advantages in comparison with the forensic autopsy.     

轿车与自行车碰撞事故仿真研究及骑车者致伤特点分析

目的研究计算机仿真技术重建自行车骑行状态下交通事故发生过程,并探讨此技术在分析真实事故中骑车者人体致伤方式、特点及损伤程度上的可行性。方法通过对事故人、车痕迹鉴定和模型建立,构建相关碰撞环境并利用高性能计算机及PC-Crash软件对事故进行再现研究。结果计算机仿真技术建立的人、车模型在模拟碰撞过程中,骑车者发生的运动过程、损伤分布及损伤动力学响应结果与法医学尸表检验人体损伤部位、程度基本吻合。结论利用计算机仿真技术重建自行车骑行状态下的事故碰撞过程、分析骑车者致伤方式及提供损伤部位动力学响应参数等,对于交通伤法医学鉴定及深化交通伤机制研究具有参考价值。     

Harness racing injuries and deaths. Report of a fatal accident and review of 178 cases

A case of a harness racing accident in which the driver died of head injuries is presented. To evaluate the victim's head injury and corresponding helmet damage, a videotape of the race was reviewed and analyzed. Based on calculations of a simplified trajectory analysis and testing of the helmet, it was determined that the helmet design did not provide adequate protection for the victim. The standards for harness helmet design are being re-evaluated by the harness racing industry to ensure the safety of the drivers. A review of 178 harness racing injuries and deaths, current harness helmet research, and recommendations for safer helmets are discussed. A protocol for the forensic investigation of sports-related injuries and/or deaths is also presented to assist medical examiners in fulfilling their roles as practitioners of preventive medicine.     

颈内动脉系钝性损伤法医学鉴定现状

颈内动脉系是大脑的主要血供来源。法医学鉴定实践中,颈内动脉系钝性损伤后常出现血栓、动脉瘤或动静脉瘘等并发症,由此引起迟发性脑梗死、颅内出血死亡的案例并不少见。目前国内对颈内动脉系钝性损伤引起死亡的研究以个案报道为主,本文综合国内外相关的文献及案例报道,对此类损伤引起死亡的法医学特点及检查方法进行总结,发现颈内动脉系钝性损伤与头颈部直接暴力或间接暴力致头颈部超生理范围运动牵拉,以及颅底骨折切割等机制有关,多见于颈部机械性窒息、颈部按摩、车祸、高坠等案例。法医学实践中若遇到此类案例,常规检查未发现梗死或出血原因,应注意检查该动脉,正确分析外伤、疾病和死亡之间的关系。鉴于尸体解剖中完整暴露该动脉的难度较大,必要时可借助血管造影技术进行定位,提高鉴定意见的科学性和可靠性。     

Driver and front seat passenger fatalities associated with air bag deployment. Part 1: A Canadian study

Real world motor vehicle collision research of injuries due to deployment of "first-generation" air bags has been conducted by Transport Canada since 1993. Fifty-three fatal crashes (36 frontal impacts; 17 side collisions) involving 48 drivers and 10 right front passengers were reviewed. In the Canadian data, air bag deployment in five of nine low severity frontal crashes (delta-V (deltaV) < 25 km/h or 15 mph) was linked to five deaths, four of whom were autopsied (four adults with craniocervical (basal skull and C2 fracture with brainstem avulsion; "closed head injury"--no autopsy) or chest trauma (aortic or pulmonary artery tears); one child with atlanto-occipital dislocation). An occupant who is close ("out-of-position") to the air bag at the time of deployment is at risk for injury. In 27 high severity frontal impacts, unusual (e.g., pulmonary "blast" hemorrhage in one autopsied case) or isolated potentially survivable injuries (e.g., clinically documented ruptured right atrium; probable flail chest observed during the autopsy on a decomposed body) localized to the head, neck or chest in three possibly out-of-position drivers pointed to the deployed air bag as a source of injury. In one of 17 side collisions an out-of-position driver sustained a radiographically confirmed C1-C2 dislocation in a minimally intruded vehicle.     

Children in motor vehicle collisions: analysis of injury by restraint use and seat location

This study was a retrospective chart review of hospital records and autopsy reports of 499 children nine years old or younger involved in motor vehicle collisions from 1994 to 1998. The objective was to evaluate the frequency and severity of injuries as a function of age, restraint use, and seat position. We found that 33% of the children were unrestrained and 20% were improperly restrained. Unrestrained children had the highest mean Maximum Abbreviated Injury Scores (MAIS) and Injury Severity Scores (ISS), accounted for 70% of the fatalities, and had the highest incidence of head injuries. Although most of the head injuries were superficial, 80% of the fatalities were the result of a head injury. Improperly restrained children had the highest frequency of abdominal injuries. Regardless of restraint use, the back seat was associated with fewer head injuries and lower mean MAIS and ISS scores compared to the front seat. Also, properly restrained children in the front seat had lower mean MAIS and ISS scores than unrestrained children in the back seat, suggesting that restraint use is more beneficial than seat position.     

The Role of Postmortem Computed Tomography in the Evaluation of Strangulation Deaths

We explored the value of postmortem computed tomography (PMCT) to augment autopsy in evaluating strangulation fatalities. A literature search identified 16 studies describing autopsy findings in 576 deaths and two studies describing autopsy and PMCT findings in six deaths. Similar cases were identified from our institution, yielding 130 deaths with autopsy findings and 14 deaths with both autopsy and PMCT findings. The presence of laryngohyoid fracture and soft tissue hemorrhage was compared from autopsy and autopsy+PMCT cases. The detection rates of fractures in autopsy and autopsy+PMCT cases were not significantly different. PMCT identified all fractures observed at autopsy and five fractures not identified. While PMCT may not detect soft tissue injuries in decomposed remains or subtle internal hemorrhages in neck injury, it is equally able to detect bony injuries as autopsy and might surpass autopsy in detecting subtle fractures. We conclude PMCT is useful to supplement autopsy in strangulation cases.     

Causes and Mechanisms of Death in Fatal Water Buffalo Attacks

Deaths due to buffalo attack have not been well described. A 72‐year‐old man was trampled by a water buffalo (Bubalus bubalis) while attempting to move the animal within an enclosed area at an abattoir. At autopsy, there were numerous injuries involving the chest, head, neck, and left upper arm. Blunt force injury had resulted in multiple rib fractures with a flail chest and fracture/dislocation of the mid‐cervical vertebrae caused either by physical crushing by the animal against the walls of the enclosure or by stomping. There was also evidence of crush asphyxia with bilateral conjunctival hemorrhages and petechial hemorrhages. In addition, there was a deep degloving injury of the upper left arm compatible with goring by one of the buffalo horns. While large animal attacks may result in death from multiple injuries, careful dissection and examination of specific injuries at autopsy may clarify the complex interaction of lethal mechanisms.     

颅脑损伤、疾病与死亡56例尸检分析

本文报道５６例尸检案例，这些案例头部确实受过损伤，并且在鉴定时必须评定颅脑损伤、疾病与死亡之间的关系。我们将这些案例分为５类，分析它们的一般情况，颅脑损伤和相关疾病的特点，它们在死亡发生中的作用等。并讨论了法医病理尸检和鉴定中的有关问题。     

Visualization and quantification of air embolism structure by processing postmortem MSCT data

Venous air embolism (VAE) is an often occurring forensic finding in cases of injury to the head and neck. Whenever found, it has to be appraised in its relation to the cause of death. While visualization and quantification is difficult at traditional autopsy, Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) offer a new potential in the diagnosis of VAE. This paper reports the findings of VAE in four cases of massive head injury examined postmortem by Multislice Computed Tomography (MSCT) prior to autopsy. MSCT data of the thorax were processed using 3D air structure reconstruction software to visualize air embolism within the vascular system. Quantification of VAE was done by multiplying air containing areas on axial 2D images by their reconstruction intervals and then by summarizing the air volumes. Excellent 3D visualization of the air within the vascular system was obtained in all cases, and the intravascular gas volume was quantified.     

Neck injuries: II. Atlantoaxial dislocation--a pathologic study of 14 traffic fatalities.

C1-C2 vertebral dislocations have not been commonly recognized at autopsy. Among 66 subjects with neck injuries, drawn from a series of 155 traffic fatalities, were 14 with injuries at the level of the atlantoaxial motion segment, ranging in age from 8 months to 93 years. Thirteen had sprains or lacerations of the atlantoaxial facet joints, and one had a healed C1 fracture. Six of the 14 had odontoid fractures. None had transverse ligament lacerations. Injuries of the alar ligaments and the tectorial membrane were frequent. Only 3 subjects had subaxial cervical injury. All 14 had evidence of impact to the head or neck. Four had fractures of the mandible or facial bones, and 5 had skull fractures. Subdural and subarachnoid hemorrhages were found in 7 and 6, respectively. Brainstem lacerations were not uncommon, but only one had a pontomedullary laceration. Spinomedullary cord injuries occurred in 5. Acute neurogenic shock was the major mechanism of death in 9 of the 14, including 5 with major cardiovascular lacerations. Delayed effects of craniocerebral trauma accounted for the majority of the remainder. The biomechanical mechanisms are discussed.     

Virtopsy,a new imaging horizon in forensic pathology: virtual autopsy by postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI)--a feasibility study

Using postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), 40 forensic cases were examined and findings were verified by subsequent autopsy. Results were classified as follows: (I) cause of death, (II) relevant traumatological and pathological findings, (III) vital reactions, (IV) reconstruction of injuries, (V) visualization. In these 40 forensic cases, 47 partly combined causes of death were diagnosed at autopsy, 26 (55%) causes of death were found independently using only radiological image data. Radiology was superior to autopsy in revealing certain cases of cranial, skeletal, or tissue trauma. Some forensic vital reactions were diagnosed equally well or better using MSCT/MRI. Radiological imaging techniques are particularly beneficial for reconstruction and visualization of forensic cases, including the opportunity to use the data for expert witness reports, teaching, quality control, and telemedical consultation. These preliminary results, based on the concept of "virtopsy," are promising enough to introduce and evaluate these radiological techniques in forensic medicine.     

Sharp force injuries in clinical forensic medicine--findings in victims and perpetrators

The injury findings in 58 perpetrators and 158 victims surviving bodily injuries due to sharp force are presented here. Defence injuries were found in 45.9% of the victims without any significant differences between males and females. There was no clear predominance of defence injuries on the left forearm and hand, as is known from autopsy studies; the right and the left hands were affected with an almost identical frequency. Regarding other parts of the victims' bodies, the topographic distribution of injuries showed a marked concentration on the left side (63.7%). The thorax, head and neck were frequently affected (45.9%, 15.3% and 15.3%, respectively), and less often the abdomen (11.1%), the lumbar and gluteal region (6.3%) and the lower extremities (6.1%). In surviving victims with only one singular stab apart from the upper limbs, the incidence of additional defence injuries on the hands and/or forearms was significantly higher (28.3%) than in fatalities. When the perpetrators had unintentionally cut their own hands, the frequency of these injuries on the right and left hands was almost equal.     

Contributions from Forensic Imaging to the Investigation of Upper Cervical Fractures

Abstract: Injuries to the upper cervical spine (UCS) are common in traumatic deaths and postmortem computed tomography (PMCT) may contribute to the forensic investigation. This study presents PMCT in comparison with autopsy in the examination of UCS injury. Thirteen consecutive cases with UCS fracture and/or cranio‐cervical dislocation were examined with PMCT and autopsy, and the findings were correlated. Neither of the techniques identified all UCS injuries. Fractures of atlas and axis were best visualized with PMCT whereas cranio‐cervical dislocation was better identified during autopsy. Serious injuries were present after both high‐ and low‐energy trauma. Medico‐legal autopsy in combination with PMCT produced a thorough evaluation of UCS injuries. By combining these procedures detailed investigations, including accident reconstruction and injury pattern analysis, can be performed. This study supports the routine application of PMCT, as a supplement to the medico‐legal autopsy of deaths with UCS injuries.