Fatal childhood vascular injuries associated with seat belt use

The deaths of two children who were passengers in motor vehicles involved in accidents were directly attributable to vascular injuries derived from seat belts. In the first case, a 10-year-old boy died as a result of abdominal aortic transection by a lap seat belt, and in the second case a 15-year-old boy died as a result of transection of his common carotid artery by a lap-shoulder seat belt. Although these cases demonstrate rare fatalities associated with seat belt use, there is no doubt that seat belts have significantly reduced mortality and morbidity from traffic accidents. Although it is possible that a fatal outcome might have occurred in each of these cases from other injuries that might have been sustained had seat belts not been worn, appropriate positioning and size of seat belt harnesses might have avoided the lethal injuries.     

Injury Pattern as an Indication of Seat Belt Failure in Ejected Vehicle Occupants

Prior authors have suggested that when occupant ejection occurs in association with a seat belt failure, entanglement of the outboard upper extremity (OUE) with the retracting shoulder belt will invariably occur, leaving injury pattern evidence of belt use. In the present investigation, the authors assessed this theory using data accessed from the NASS‐CDS for ejected front seat occupants of passenger vehicles. Logistic regression models were used to assess the associations between seat belt failure status and injuries. Injury types associated with seat belt failure were significant OUE and head injuries (OR = 3.87, [95% CI 1.2, 13.0] and 3.1, [95% CI 1.0, 9.7], respectively). The two injury types were found to be a predictor of seat belt use and subsequent failure only if combined with a high (≥0.8) precrash probability of belt use. The injury pattern associated with a seat belt failure‐related ejection has limited use in the forensic investigation of crash‐related ejections.     

Neck injuries caused by automatic two-point seat belts: an analysis of four cases

Although seat belts significantly reduce the extent and severity of injuries sustained by motor vehicle occupants, seat belts are known to be associated with chest and abdominal trauma. Less commonly understood are severe neck injuries caused by the use of two-point automatic shoulder harnesses without concurrent use of a manual lap belt. Such injuries may include cervical spine fractures, craniocervical dislocations and rarely decapitation. Recognizing patterned injuries caused by seat belts and the ability to correlate autopsy findings with the circumstances surrounding the death will allow for correct interpretation of seat-belt related trauma. The four cases described detail fatal neck injuries as a result of improper seat belt use in which an automatic two-point shoulder harness was used without a manual lap restraint. In two of the cases, the victims were decapitated.     

Asphyxiation from shoulder seat belts: an unusual motor vehicle injury

Two cases of accidental asphyxia caused by lap-shoulder seat belts are reported. Lethal neck injuries from shoulder seat belts are uncommon, and episodes of asphyxiation are even rarer. Positioning of the shoulder belt over the neck, short stature, and incapacitation from other injuries were predisposing factors to upper airway compromise in these cases.     

Motor Vehicle Occupants,Neck Injuries,and Seat Belt Utilization: A 5‐Year Study of Fatalities in New York City

Abstract: Despite the implementation of numerous safety devices in automobiles, vehicular occupant fatalities following collisions remain common. We reviewed all fatalities of vehicular occupants in New York City over a 5‐year period on whom autopsies were performed (437) to determine the incidence of neck injuries and correlate them with seat belt utilization; 26.5% had neck injuries (mild to severe) and only 10.3% of these occupants were confirmed to be wearing seatbelts. Of those that had documentation of seat belt utilization there were twice as many neck injuries in the unbelted group. We highlight two cases of submarining with severe neck injuries that were related to automatic 2‐point shoulder harness restraints without engagement of the lap belt.     

Reforming Public Safety: An Evaluation of the 1983 British Seat Belt Law

The purpose of this paper is to analyze the impact of the 1983 British seat belt law in England and Wales. The methodology employed is interrupted time series analysis.
In terms of a lasting impact, the seat belt legislation for automobiles compares favorably with other interventions designed to decrease deaths and injuries on the road, such as legislation to control drinking and driving. Typically, such legislation is effective only in the short term. In contrast, the seat belt law thus far shows a stronger and more lasting shift in the reduction of serious and fatal car casualties. The post intervention decline in this variable is stronger than a control series that consists of the number of fatal and serious non-car casualties. A more marginal reduction is found for non-serious car casualties even though this drop in injuries is slightly stronger than a control category of nonserious non-car casualties. The paper suggests also that the seat belt legislation may have had a short term effect on the number of fatal and serious accidents on weekend nights, the period of time during which alcohol-related crashes are most likely to occur.
The policy implications of this study suggest that with comparable compliance, such an intervention may similarly be effective in the United States and other Western countries which up to now have used primarily deterrence-based approaches to reduce highway casualties.     

Murder and robbery by vehicular impact: true vehicular homicide

True vehicular homicides are defined as those occurrences in which a motor vehicle is intentionally used as a weapon in taking of a life. A case is presented in which the deceased was traveling in the front passenger seat of a motor car that was deliberately rammed by a heavy jeep that came in the opposite direction, resulting in a serious frontal collision. Immediately after the impact, while the occupants of the car were lying in a dazed condition, the two persons riding in the jeep escaped with a bag containing money that was in the car, leaving the jeep behind. The impact mainly involved the driver's sides of both vehicles. The driver of the car sustained serious injuries but was found to be alive, whereas the front-seat passenger, who did not show any serious external injuries, was found to be in a collapsed state and was pronounced dead on admission to the hospital within 30 minutes of the accident. The autopsy revealed that death was caused by closed hemopericardium from a ruptured right atrium. The evaluation of the external and internal injuries confirmed that the fatal injury and a few serious internal injuries were caused by the seat belt (tertiary-impact injuries). The ruptured right atrium was attributed to blunt abdominal trauma by impacting against the lap belt. The case was a true vehicular homicide in which a motor vehicle had been used as a weapon to kill a person. Various aspects pertaining to road accidents, the safety of the occupants, and the advantage and disadvantage of the safety devices are discussed.     

Cervical airway injuries as a result of impact with steering wheel rim

Motor vehicle occupants may suffer severe cervical airway injuries as the result of impaction with the steering wheel, dashboard, windshield, backseat, and seat belt. Although the steering column is well recognized as a general site of injury infliction, less attention has been directed to components which may be the actual focal point of contact, such as the steering wheel rim. Two cases of cervical airway injury as a result of impact with the steering wheel rim are presented, including one instance of complete laryngotracheal transection. Correlation of injury with crash and postcrash sequences as well as the damaged vehicle will often provide excellent crash injury reconstruction.     

Injury patterns in motor vehicle fatalities

A retrospective pilot study of motor vehicle incident fatalities was conducted to determine what relationships exist between injuries received by deceased drivers, passengers, and a control population of pedestrians, and some of the environmental factors existing at the time of the incident. A number of correlations were established between the types and locations of injuries received, seat belt use, position of the injured party, and so forth. A study of this type, if performed on a large enough population, could lead to predictive models for the determination of position of the victims within a motor vehicle at the time of a fatal crash, based on a unique clustering of injuries.     

Forensic Performance Analysis of Load‐Limiting Devices in Automotive Seat Belt Retractors

The introduction of frontal airbags and seatbelt pretensioners for front seat occupants provided an opportunity to address injuries caused by seatbelt loading by introducing load‐limiters, which were intended to reduce belt loading while maintaining proper restraint. Investigation and forensic analysis of real‐world crashes identified that the implementation of these devices, in some circumstances, increased the potential of injury. This paper focuses on the trade‐offs of load‐limiters, that is, the reduction loading to the occupant versus the corresponding increase in seatbelt webbing and occupant movement. If the additional webbing introduced is not controlled, the risk of injury to the occupant is increased and could result in more frequent and severe injuries rather than a reduction. This paper quantifies the webbing introduced by load‐limiter activation through forensic analysis of the seatbelt involved in real‐world crashes and testing and assesses its effect on the injuries sustained by the occupant.     

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.     

An examination of the New York mandatory seat belt law on a university campus

On January 1, 1985, the mandatory seat belt law went into effect in New York State; violators were now subject to a fine of $50.00. Police officers issued nonpenalty-based warnings during the month prior to the law's imposition. The purpose of the present study was to compare the effects of the warning versus the fine and a fine-plus-prompt condition (the prompt delivered by the experimenters) on seat belt use on a university campus. Results indicated that significantly more drivers used their sear belts during the fine conditions as compared with the warning condition and that significantly more female drivers used their seat belt during all conditions. A significant difference was not found, however, between the fine and fine-plus-prompt conditions.We gratefully acknowledge the comments of Michael Leippe on an earlier draft of this manuseript.     

Study of injuries combining computer simulation in motorcycle-car collision accidents

This paper presents the approach of computer simulation to clarify the questions faced by forensic experts about what causes the various injuries characteristic of two motorcycle victims, including the motorcycle driver and the back seat occupant on the motorcycle, and how to exactly confirm which one of them is the motorcycle driver. Two typical motorcycle-car accident cases were reconstructed to analyze the movement and the load of both the motorcycle driver and the back seat occupant in the collision course. In case one, the back seat occupant suffered fatal head injuries when he fell on the ground after being thrown higher than the motorcycle driver over the top of the car. In case two, the compressive force loaded by the right tibia of the back seat occupant was larger and more durative compared with the motorcycle driver; the back seat occupant suffered a bursting fracture injury of his right tibia. These results might be useful for forensic experts in dealing with similar motorcycle-car collision accidents in the future.     

立法的被“俘获”与“逃逸”——从“安全带法”看社会科学知识对立法的影响

安全带法(驾车时强制要求系安全带的规定)已经是一种全球性的法律,其广泛存在在很大程度上源于对安全带能大幅度降低机动车乘坐人的伤亡率的确信。但风险补偿理论论证了安全带法并不能使道路交通更安全,大量的实证研究也证实了这一点。尽管有安全带更安全的神话已经破灭,但各国的立法者对此却无动于衷,或许这可归因于法学的保守性、制度的路径依赖、社会选择的影响以及法学一定程度的不自足性。由此生发开去,立法活动与社会科学知识的关系更加值得人们深思。     

Amniotic fluid embolism as cause of death in a car accident--a case report

Amniotic fluid embolism (AFE), a relatively rare complication in pregnancy, has a high mortality rate. We describe a case of a 38-week pregnant woman with such an embolism leading to almost immediate death after a blunt abdominal trauma inflicted in a motor vehicle accident and probably associated with improper positioning of a seat belt. It has been assumed that the pathophysiology of amniotic fluid embolism is related to an anaphylactoid reaction and that mast cell degranulation indicates this mechanism. Moreover, immunohistochemical antitryptase staining of pulmonary tissue samples in our case revealed mast cell degranulation.     

Suicidal hanging within an automobile.

Accidental asphyxia related to cars has been described in different reports, but suicidal hanging in an automobile is very unusual. Two cases of suicidal hanging inside an automobile are described, illustrating an unusual form of hanging. In one case, the deceased used his belt as a ligature, and the point of attachment was the window of the car. The second victim used the safety belt of the passenger seat. In both cases, the automobile engine was turned off, all the windows were closed, and the door locks were blocked. The medicolegal cause of hanging was based on the scene of the investigation, police and witness reports, social history, autopsy findings, and toxicologic examinations.     

Seat belt induced transection of the trachea in a child on the lap of an adult

As a victim of his parents' suicide, a three-year-old boy was found dead on the lap of the passenger in the left front seat of a car that dove from the wharf and crashed into the sea. He died from the transection of trachea due to shoulder belt in the absence of the signs of drowning. The seat belt paradoxically injured the child on the passenger's lap in the traffic accident. The popular custom of Japanese parents of holding their children on their laps in cars is dangerous, while another custom of killing their children upon suicide of parents or couples should be socially and legally controlled.     

Forensic Epidemiologic and Biomechanical Analysis of a Pelvic Cavity Blowout Injury Associated with Ejection from a Personal Watercraft (Jet‐Ski)

Jet‐propelled personal watercraft (PWC) or jet‐skis have become increasingly popular. The means of propulsion of PWC, which is a jet of water forced out of small nozzle at the rear of the craft, combined with a high risk of falling off of the seat and into close proximity with the water jet stream, raise the potential for a unique type of injury mechanism. The most serious injuries associated with PWC falls are those that occur when the perineum passes in close proximity to the jet nozzle and the high‐pressure water stream enters the vaginal or rectal orifice. We describe the forensic investigation into a case of an anovaginal “blowout” injury in a passenger who was ejected from the rear seat position of a PWC and subsequently suffered life‐threatening injuries to the pelvic organs. The investigation included a biomechanical analysis of the injury mechanism, a summary of prior published reports of internal pelvic injuries resulting from PWC falls as well as other water sports and activities, and a comparison of the severity of the injuries resulting from differing mechanisms using the New Injury Severity Score (NISS). The mean (±standard deviation [SD]) NISS values for reported PWC injuries [not including the NISS of 38 in this case study] were 11.2 (±9.5), while the mean value for reported water‐skiing falls was half that of the PWC group at 5.6 (±5.2). It was concluded that the analyzed injuries were unique to a PWC ejection versus other previously described non‐PWC‐associated water sport injuries. It is recommended that PWC manufacturers help consumers understand the potential risks to passengers with highly visible warnings and reduce injury risk with revised seat design, and/or passenger seat “deadman” switches.     

The effect of the unrestrained back seat passenger on the injuries suffered by drivers and front seat passengers in head-on collisions

In head-on collisions, loose items in the rear of the car, such as luggage or unrestrained back seat passengers can cause substantial loading on the back of the front seats. The purpose of this paper is to study if such loading increases the injury severity for the front seat occupants. Data were collected from all fatal automobile accidents for a period of 1 year in Sweden. Information was collected about the survivors as well as the decreased. Head-on collisions were selected, and the injuries of the front seat occupants were scored according to the Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS). In evaluating the injury severity, the collision energy was taken into account. The results indicate that belted front seat passengers sustain a higher injury risk with an unrestrained passenger in the back seat. These results are valid for collision speeds below 45 km/h.     

车外人员撞击伤特点分析

目的以真实案例为基础,研究汽车碰撞事故中,不同机动车车型、不同交通方式等因素造成车外人员撞击伤的特征。方法选取上海地区发生的汽车与车外人员碰撞事故案例200例,通过对事故中的人、车等检验对比,分析车外人员撞击伤的特点。结果车外人员撞击伤主要出现在下肢,其次为胸部和头部;行人（含推车人）撞击伤出现频次与骑车人（含自行车或摩托车后座乘员）无明显差异;小轿车和小客车事故中撞击伤多见于下肢,大客车多见于胸部;车外人员被撞击后发生抛甩频率随车速的加大而增高,且通过车体痕迹检验,人体与车辆挡风玻璃发生（二次）撞击伤匹配程度最高。结论分析汽车与车外人员碰撞事故人体撞击伤特点,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。