Safety belt restraints and compartment intrusions in frontal and lateral motor vehicle crashes: mechanisms of injuries, complications, and acute care costs

A 3-year prospective study examined 76 frontal (F) and 45 lateral (L) motor vehicle crash (MVC) patients with regard to seatbelt restraint use and occupant compartment contact and intrusion injuries. These 121 MVC victims with multiple injuries (39 belted [B] and 82 non-belted [NB]), admitted to a level I trauma center, were studied by accident reconstruction and medical data analysis. They had a MVC mean impact velocity (delta V) of 30 +/- 11 mph and an injury Severity Score of 29 +/- 12. Proper restraint use reduced brain injury in F MVCs (30% FB vs. 47% FNB) but had no effect in L MVCs (63% LB vs. 30% FB [p < 0.06]). Belt use did not protect against lung, liver, spleen, pelvis, or lower extremity (LE) injury. These appeared to be more a function of crash direction, with LE injuries higher in F crashes (p < 0.04) and pelvis injuries (p < 0.001) higher in L crashes. In FB crashes, however, properly used safety restraints were the primary cause of bowel or colon injuries (p < 0.006). Belts did not prevent thoracic or abdominal solid organ injuries in L crashes. Contact-intrusions (CI) of the car occupant compartment in F crashes were the main cause of brain (A-pillar), lung and liver (steering wheel and instrument panel), and LE (toepan) injuries; but in L crashes, side-door CI caused lung, aorta, liver, and pelvic injuries. In contrast, contact-only (CO) injuries of the steering assembly were mainly responsible for injuries to the lung, heart, and liver in F crashes, and side-door CO for lung, liver, and spleen injuries in L crashes. Deaths and complications after injury were higher among F MVC occupants, or when delta V was > or = 30 mph. Hospital and professional costs reflect the complex care needed for victims of multiple injuries: FB, $99,000; FNB, $95,000; LB, $75,000; LNB, $79,000; total, $10.7 million. Present vehicle safety standards are not adequate, and structural design changes are needed to improve restraints and protect occupants from intrusion-related injuries.     

Searching for regulatory elements in human noncoding sequences

Injury type and severity among front outboard occupants of passenger vehicles struck in the side by another passenger vehicle and recorded in the United States National Accident Sampling System Crashworthiness Data System were examined in relation to the location of impact, the angle of impact, occupant gender and age, seat belt use, the weight and body style of the side-impacted vehicle, and the weight and body style of the striking vehicle. Elderly occupants were three times as likely as younger occupants in similar crashes to be seriously injured. Serious injuries were also more likely for occupants seated on the struck side and occupants of lightweight passenger vehicles. After accounting for vehicle weight differences, struck-side occupants of cars were still much more likely to be seriously injured than struck-side occupants of light trucks. However, among occupants seated on the side of the vehicle opposite the impact, the likelihood of serious injury was higher for those seated in light trucks.     

Risk of injury to restrained children from passenger air bags

The objectives of this study were to estimate the prevalence of children's exposure to passenger air bag (PAB) deployments and to determine the relative risk of both minor and more serious nonfatal injuries to restrained children exposed to PABs in frontal impact collisions. Data were collected from 1 December 1998 to 30 November 2001 from a large-scale, child-specific crash surveillance system based on insurance claims, a telephone survey, and on-site crash investigations. Vehicles qualifying for inclusion were State Farm-insured, model year 1990 or newer, and involved in a crash with at least one child occupant < or =15 years of age. Qualifying crashes were limited to those that occurred in 15 states and the District of Columbia. A stratified cluster sample was designed in order to select vehicles (the unit of sampling) for the conduction of a telephone survey with the driver. For cases in which child occupants were seriously injured or killed, in-depth crash investigations were performed. The prevalence of exposure to PABs was calculated as the number of children occupying the right front seat in a PAB deployment crash among all children occupying the right front seat in vehicles equipped with PABs. Complete interview data were obtained on 9,779 vehicles involving 15,341 children. Among PAB-exposed children, 175 (14%) suffered serious injuries versus 41 (7.5%) of those in the comparison group (OR 2.0; 95% CI, 1.1-3.7). The overall risk of any injury (both minor and serious) was 86% among children exposed to PABs, compared to 55% among the comparison group (OR 5.3; 95% CI, 2.1-13.4). Exposure to PABs increased the risk of both minor injuries, including facial and chest abrasions, and more serious injuries, particularly upper extremity fractures.     

Patterns of injury in belted and unbelted individuals presenting to a trauma center after motor vehicle crash: seat belt syndrome revisited

STUDY OBJECTIVE: Investigators have described a "seat belt syndrome" consisting variously of injuries to the lumbar or cervical spine, abdominal contents, or all 3. In this study we sought to identify these and any other patterns of injury associated with seat belt use in patients who presented to a trauma center after a motor vehicle crash. METHODS: The charts of all patients involved in motor vehicle crashes who presented as trauma alerts to the study institution between January 1, 1991, and December 31, 1993, were retrospectively reviewed for data regarding belt use and 35 specific injuries in 7 body regions. We calculated the positive likelihood ratio of injury between belted and unbelted patients, along with 95% confidence intervals. RESULTS: We identified 1,124 patients involved in motor vehicle crashes. Of these subjects, 376 were belted and 544 unbelted; in 204 belt status was unknown. Belted patients were more likely to have sustained sternal fracture than were unbelted patients (4% versus .7%; positive likelihood ratio, 1.97; 95% confidence interval, 1.09 to 3.29) but were less likely to have sustained head injury (30.6% versus 46.0%; positive likelihood ratio, .67; 95% confidence interval, .53 to .83). We noted no statistically significant differences in the rates of other specific injuries, including cervical and lumbar fractures and the need for abdominal surgery. CONCLUSION: Severe injuries of all types occur in both belted and unbelted individuals involved in motor vehicle crashes who present to a typical trauma center. With the exception of sternal fractures, injuries previously associated with the seat belt syndrome occurred in similar proportions of belted and unbelted patients. Head injuries were less frequent. Seat belt use cannot serve as a discriminator for specific injury. A diligent search of all body regions is indicated in both belted and unbelted patients.     

Estimates of motor vehicle seat belt effectiveness and use: implications for occupant crash protection

Estimates of the effectiveness of seat belts, when used, in reducing motor vehicle occupant deaths vary widely. A recently publicized claim by one analyst that seat belts reduce vehicle occupant deaths 70-80 per cent is based on studies found to contain fundamental systematic error. Deaths occur only 50 per cent less often to belted compared to nonbelted vehicle occupants in crashes, according to previously unanalyzed data from three U.S. states during recent years. New belt systems would be about 60 per cent effective with 100 per cent use. But surveys of observed belt use in 1975 U.S. cars indicate that two-thirds of drivers were not using belts. Prospects for widespread adoption and enforcement of belt use laws in the U.S. are not encouraging. Substantial reductions in fatal and other injuries would result from the adoption of requirements mandating automatic (passive) protection for front seat occupants in crashes with forward decelerations.     

The effect of associated injuries, blood loss, and oxygen debt on death and disability in blunt traumatic brain injury: the need for early physiologic predictors of severity

Studies of 4590 patients with blunt trauma injuries admitted to a Level I Trauma Center, have shown that 37% had a blunt traumatic brain injury (BTBI). Of these brain injured patients 60% has an associated other injury. Examination of mortality has shown that those with an isolated brain injury had an 11% mortality compared with 21.8% in those with an associated systemic injury. Further investigation demonstrated that the cause of the increased mortality was related to the blood loss associated with the injuries and that when hypovolemic shock resulted, mortality rose from 12.8 to 62%. The severity of the associated injuries effect on the brain injured patient could be estimated by a parameter of oxygen debt, the base deficit and this allowed for a quantitative estimate of the probability of death as an index of severity. A combined linear logistic model using the admission Glasgow Coma Score (GCS) as a measure of brain injury and the base deficit as a measure of physiologic injury provides such a predictive score. The effect of associated injuries in patients with moderate brain injury (AIS 2,3) was to increase the average total cost of medical care in the first year of injury by three-fold ($12,489 to $36,177) and for severe brain injury (AIS 4,5) to increase average cost from $59,000 in isolated BTBI to $90,000 in BTBI with associated injury. The high incidence of brain injuries in motor vehicle crashes (MVC) caused by lateral impacts and their association with other side-impact injuries (lungs, spleen, kidney, and pelvic fractures) in which large blood volume losses are common, focuses attention on the need for side impact protection standards that simultaneously protect brain, thoracoabdominal viscera, and pelvis as a means of reducing the severity and cost of lateral impact MVCs.     

Increases in crash involvement and fatalities among motor vehicle occupants younger than 5 years old

OBJECTIVE: To determine whether increased exposure as car occupants could be a major contributor to increases observed in deaths of young children in car crashes. DESIGN AND SETTING: Crash data from police reports for Maryland, Michigan, Pennsylvania, and Washington for various years from 1982 through 1990 were examined to compare annual age mix of injured and uninjured occupants in crashes involving at least two passenger vehicles. Aggregate national data from the Fatal Accident Reporting System were also examined over the same time period and compared to population estimates for children younger than 5 years old to assess temporal trends in number of occupants in this age group who were involved in motor vehicle crashes in which a fatality occurred in fatal crashes and the number of them killed in passenger vehicles. RESULTS: In regression analyses for each state, the number of car occupants younger than 5 involved in crashes increased during the years studied; their percentage among nondriver occupants involved also increased. At a national level, similar analyses showed increases in the number of occupants younger than 5 involved in crashes in which a fatality occurred. CONCLUSIONS: Despite overall increases in the use of restraint devices (ie, both child safety seats and adult restraints), fatalities among restrained children have increased. Given that exposures to crash environments are increasing, clinicians need be aware of the importance of child restraints as a means of reducing the likelihood of injury.     

Anterior lung herniation: another aspect of the seatbelt syndrome

Shoulder harnesses can be a source of thoracic injury in motor vehicle crashes. Sternal and rib fractures are most commonly reported. We present a case of a traumatic anterior lung herniation secondary to shoulder harness trauma in a motor vehicle crash victim with multiple injuries. A brief review of lung hernias is provided as well as a brief discussion of the thoracic manifestations of the seatbelt syndrome.     

Factors associated with fatalities and injuries from hot-air balloon crashes

CONTEXT: Despite the increased popularity of hot-air balloon flight, data on injuries and fatalities associated with hot-air balloon crashes are limited. OBJECTIVE: To determine factors associated with injury and death in hot-air balloon crashes. DESIGN: Retrospective review of data collected from reports and investigations by the Civil Aeronautics Board and the National Transportation Safety Board. STUDY SUBJECTS: Individuals involved in US hot-air balloon crashes from 1964 to 1995. MAIN OUTCOME MEASURES: Total number of crashes and factors associated with fatality or serious injury. RESULTS: From 1964 to 1995, a total of 495 hot-air balloon crashes involving 1533 persons were reported and included 92 fatalities and 384 serious injuries. Pilot error or incapacitation was determined subjectively by crash investigators to contribute to 85.1% of the crashes. In univariate analysis, collision with the ground was the most significant predictor of a fatality or serious injury (P<.001), and power-line contact was the most significant predictor of fatality (P<.001). In multiple logistic regression, only the type of object struck by a balloon predicted a fatal crash or a fatality or serious injury. CONCLUSIONS: Although a number of factors likely contribute to increased severity of hot-air balloon crashes, the object struck during a crash is most predictive of fatality or serious injury. Preventive efforts are needed to decrease future injuries.     

Neck strain in car occupants. The influence of crash-related factors on initial severity

OBJECTIVE: To examine the relationship between the initial severity of neck strain in car occupants and crash-related factors, in particular, crash severity. DESIGN/PARTICIPANTS: Thirty-two individuals with neck strain after a car crash, drawn from physiotherapy and general practices in metropolitan Adelaide, were interviewed about their experience and examined by a manipulative physiotherapist. Crash severity was assessed by measurement of damage to the involved vehicles. MAIN OUTCOME MEASURES: Five measures of neck strain severity were obtained: number of body regions with symptoms, number of positive responses to palpation, cervical range of motion, subject's own rating on an analogue pain scale, and examiner's severity rating. Two measures of crash severity were used: maximum residual deformation, and velocity change of the subject's vehicle. RESULTS: Neck strain was observed in individuals who were involved in crashes of low severity. Maximum residual deformation of the vehicle was negatively associated with the subject's cervical range of motion and positively associated with the other measures of neck strain severity. For rear impacts, both measures of crash severity were associated with measures of neck strain severity. The group of subjects who were aware of the impending collision had a greater range of cervical spine movement and fewer positive responses to palpation than those who were unaware. CONCLUSIONS: Initial severity of neck strain is positively correlated with crash severity. Awareness of the impending collision may have a mitigating effect on injury severity.     

Orion Crew Member Injury Predictions during Land and Water Landings

A review of astronaut whole body impact tolerance is discussed for land or water landings of the next generation manned space capsule named Orion. LS-DYNA simulations of Orion capsule landings are performed to produce a low, moderate, and high probability of injury. The paper evaluates finite-element (FE) seat and occupant simulations for assessing injury risk for the Orion crew and compares these simulations to whole body injury models commonly referred to as the Brinkley criteria. The FE seat and crash dummy models allow for varying the occupant restraint systems, cushion materials, side constraints, flailing of limbs, and detailed seat/occupant interactions to minimize landing injuries to the crew. The FE crash test dummies used in conjunction with the Brinkley criteria provides a useful set of tools for predicting potential crew injuries during vehicle landings.     

Testicular torsion before 6 hours. I

BACKGROUND: Following the crash of a Boeing 737-400 aircraft on the M1 motorway at Kegworth, near Nottingham, England, on January 8, 1989, it became apparent that a large number of pelvic and lower limb injuries had been sustained by the survivors. Had there been a fire, these injuries would have severely hindered the ability of the occupants to escape. The mechanism of pelvic and lower limb injuries in impact accidents previously has been related to flailing of the limbs and axial loading of the femur as in automobile accidents. HYPOTHESIS: A bending load is the primary mechanism of femoral fracture in an impact aircraft accident rather than an axial load. METHODS: Two methods of study have been used to investigate the impact biomechanics of the pelvis and lower limb: a) clinical review of the injuries sustained in the M1 Kegworth accident; and b) impact testing. RESULTS: A clinical review of the M1 aircrash survivors suggested that axial loading was not the primary mechanism causing femoral fractures and suggested that a bending load might be applied to the femur. Impact testing confirmed that axial loading of the femur did not appear to be significant. CONCLUSIONS: Our study suggests that in the presence of intact occupant protection systems, a femoral bending mechanism involving the front seat spar of passenger seats is a primary cause of femoral fracture in an impact aircraft accident.     

Hospital inpatient costs resulting from road crashes in Western Australia

The purpose of this study was to estimate the inpatient costs of road crashes in Western Australia, and to investigate factors relating to casualties and their injuries that affect the hospital costs resulting from road crashes. All road crash casualties who were injured severely enough to be hospitalised in Western Australia in 1988 were included. A casemix classification system was used to classify patients into diagnostic related groups. Hospital costs were assigned to individual patients on the basis of their diagnostic related group and length of hospital stay. The annual cost of hospital treatment for road crash casualties was estimated as $13.9 million, and 33 per cent of this was incurred by those with lower extremity injuries and 27 per cent by those with head injuries. Hospital costs per casualty ranged from an average of $1388 for those sustaining minor (Abbreviated Injury Scale severity score of 1 or 2) spinal injuries to $16,580 and $33,424, respectively, for those sustaining severe (Abbreviated Injury Scale severity score of 4 or 5) head and spinal injuries. A multivariate analysis of variance revealed the following factors as having a significant independent effect on the hospital inpatient costs of road crash casualties: type of hospital (teaching or nonteaching), body region of injury, injury severity level and road user group. There were also significant interaction effects between different factors. Since hospital inpatient costs vary considerably across factors, using average cost data in the specific economic evaluation of road safety interventions for groups of road users is inappropriate.     

Alcohol intake and severity of injuries on highways in Mexico: a comparative analysis

AIMS: To analyze the association between alcohol intake and the severity of injuries sustained from traffic accidents on a Mexican highway. DESIGN: An observational unit evaluated drivers involved in auto accidents. SETTING: Mexico-Cuernavaca Highway, Mexico. A 60 km-long road with many altitude variations and sharp curves. PARTICIPANTS: Three hundred and eighty-six drivers involved in traffic accidents between March and September, 1994. MEASUREMENTS: A questionnaire was applied to the driver, an occupant or witness at the site of the accident to collect information about the driver, vehicle characteristics, type of accident, day-night occurrence, road section (Mexico-Cuernavaca or Cuernavaca-Mexico) and weather conditions. A physical examination was carried out to determine the presence and severity of injuries. FINDINGS: There were 177 injured people, including 12 deaths, with rates of 67.5 injuries and 4.58 deaths per 10,000 km driven. Variables associated with alcohol intake (p < 0.05) included: severity of injuries, non-use of seat belt, vehicle size and occurrence at night. Risk factors for severe injuries were: alcohol intake (adjusted OR 6.1 CI 95% 1.6-24.0); non-use of seat belt (OR 4.9 CI 2.2-10.8), age < 25 years (OR 3.6 CI 1.0-12.7), age > 54 years (OR 6.0 CI 1.4-25.0), speed > 90 km/h (OR 2.6 CI 1.1-6.3) and occurrence at night (OR 2.6 CI 1.3-5.3). CONCLUSIONS: Alcohol intake is a major risk factor for severe injuries from highway traffic accidents. Its association with other risk factors such as non-use of seat belt and excessive speed suggests the importance of designing interventions aimed at reducing alcohol intake among automobile drivers.     

Improving health care, Part 5: Applying the Dartmouth clinical improvement model to community health

BACKGROUND: Traditional approaches to community health initiatives provide guidance on community mobilization, health assessment, planning, and intervention. Yet direction in how to frame the action steps to implement and measure results is often missing. Many community health initiatives find implementation overwhelming and ineffectual. FRAMEWORK FOR COMMUNITY HEALTH-THE CLINICAL IMPROVEMENT MODEL: The process--outcome methodology of continuous quality improvement (CQI) can translate large community aims into manageable projects. The sequential application of the clinical improvement model and the Community Health Value Compass for measuring outcomes-in state of health, quality of life, satisfaction, and costs-provides a link between data and action, thereby producing accountability for the community health initiative. USING THE CLINICAL IMPROVEMENT MODEL IN TWIN FALLS: Healthy Magic Valley (Twin Falls, Idaho) is the vision for long-term improvement in health status and reduction of health risks for the Southcentral Idaho Health Network. Since 1996 the Twin Falls Community Health Collaborative and SAFE KIDS Coalition have used the Value Compass model and CQI methods to decrease the rate of motor vehicle collisions, serious injuries, and deaths involving teens, while reducing the health, educational, legal, and financial consequences associated with teen-involved motor vehicle collisions. In 1993 the Twin Falls collaborative convened to apply CQI methods to the health of the community. The team has since met periodically to address the issues of community health, using the Dartmouth value compass model since 1996. Each sequential application of the process-outcome CQI framework exposes a blueprint for action and the unfolding of a health improvement strategy. The interventions should affect one or more dimensions of the value compass for teenage driving and motor vehicle collisions. CASE STUDY OF THE CLINICAL IMPROVEMENT MODEL: The motor vehicle death in October 1997 of a high school football player, who was not wearing a seat belt, led to a call to action for injury prevention. Implementation of a local community health initiative on seat belt use started in 1998. A strategy was developed to address implementation of the project among high school teens (for immediate impact) and elementary school children (for long-term impact) and to promote collaboration between the school and the rest of the community. RESULTS: Observed use of seat belts increased from January to September 1998. Data on fatality rates; injury rates; percentages of teens in crashes, of teens injured, and of teen collisions involving use of alcohol; and comprehensive costs are also monitored. DISCUSSION: Once coalitions are built and priorities set, the Dartmouth clinical improvement model presents a method that emphasizes measuring the benefits to the individual members of the community. A portfolio composed of a value compass for each health improvement initiative provides ongoing feedback for guiding subsequent strategic planning by the governing community health network.     

A microbore high performance liquid chromatography/electrospray ionization mass spectrometry method for the determination of the phytoestrogens genistein and daidzein in comminuted baby foods and soya flour

Motor vehicle crashes are a leading cause of death and disability among children in the United States despite the fact that child safety seats and seat belts can provide effective protection against serious and fatal injuries. Many child car seats and safety restraints are being used incorrectly. In addition, recent fatalities associated with children and air bags have heightened awareness of child passenger safety issues. Pediatric nurse practitioners are in an excellent position to offer motor vehicle occupant prevention strategies to families through health education and anticipatory guidance.     

Professional drivers: protection needed for a high-risk occupation

"On the job" motor vehicle deaths number more than 4,000 annually in the U.S. and comprise nearly one-third of all work-related deaths. Yet the Department of Labor has set no standards relating to on-the-road safety of the millions of workers whose jobs entail large amounts of driving, and Department of Transportation standards affecting occupational safety cover only drivers in interstate commerce. Drivers of some commercial vehicles, such as heavy trucks, are at special risk of injury because trucks have usually been exempted for many years from federal motor vehicle safety standards--such as standards for brakes and seatbelts--designed to prevent crashes or protect occupants in crashes. Observations based on a series of 150 fatal crashes involving tractor trailers illustrate the need for better protection of this large population of high-risk workers. Clarification of responsibility within the various federal agencies and application of available knowledge and technology are essential.     

Fatal crashes of passenger vehicles before and after adding antilock braking systems

Fatal crash rates of passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. Vehicles selected for analysis had no other significant design changes between the model years being compared, and the model years with and without antilocks were no more than two years apart. The overall fatal crash rates were similar for the two model years. However, the vehicles with antilocks were significantly more likely to be involved in crashes fatal to their own occupants, particularly single-vehicle crashes. Conversely, antilock vehicles were less likely to be involved in crashes fatal to occupants of other vehicles or nonoccupants (pedestrians, bicyclists). Overall, antilock brakes appear to have had little effect on fatal crash involvement. Further study is needed to better understand why fatality risk has increased for occupants of antilock vehicles.     

Trends in motorcyclist and occupant fatalities and serious injuries due to traffic crashes

AIM: To describe trends in motorcycle traffic crashes and compare these trends in other crashes and vehicle registrations. METHOD: National fatality and public hospital inpatient data were used to select cases. Relative changes in both deaths and hospitalisations, and vehicle registrations were examined in each year during the period 1980-98. RESULTS: The results show that deaths and serious injuries to motorcyclists have declined substantially over the period 1980-1995. The trend in serious injuries to motorcyclists closely followed the trend in motorcycle registrations. The association was less evident for motorcyclist fatalities and for occupants there was no clear association with trends in registrations for either outcome. CONCLUSIONS: The reduction in motorcycle injuries has contributed substantially to our improved road safety record. We need to protect these gains but in order to do this we need a clear understanding of how they were achieved. Such an understanding is currently lacking.     

Visual processing impairment and risk of motor vehicle crash among older adults

CONTEXT: Motor vehicle crash risk in older drivers has been associated with visual acuity loss, but only weakly so, suggesting other factors contribute. The useful field of view is a measure that reflects decline in visual sensory function, slowed visual processing speed, and impaired visual attention skills. OBJECTIVE: To identify whether measures of visual processing ability, including the useful field of view test, are associated with crash involvement by older drivers. DESIGN: Prospective cohort study with 3 years of follow-up, 1990-1993. SETTING: Ophthalmology clinic assessment of community-based sample. PATIENTS: A total of 294 drivers aged 55 to 87 years at enrollment. MAIN OUTCOME MEASURE: Motor vehicle crash occurrence. RESULTS: Older drivers with a 40% or greater impairment in the useful field of view were 2.2 times (95% confidence interval, 1.2-4.1) more likely to incur a crash during 3 years of follow-up, after adjusting for age, sex, race, chronic medical conditions, mental status, and days driven per week. This association was primarily mediated by difficulty in dividing attention under brief target durations. CONCLUSION: Reduction in the useful field of view increases crash risk in older drivers. Given the relatively high prevalence of visual processing impairment among the elderly, visual dysfunction and eye disease deserve further examination as causes of motor vehicle crashes and injury.