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This study utilizes a unique database that allows for the calculation of the correlation of injuries to child passengers involved in motor vehicle accidents with the restraint system and the accident characteristics. The database contains 4600 records of accidents involving children age 12 and under that occurred in 13 counties in western New York State during 1991 and 1992. Injured subjects and non-injured subjects were selected from data provided by the New York State Department of Motor Vehicles identifying reported accidents involving the target population in the time period and geographical area defined. The data sources included police accident reports, emergency medical team reports, hospital records and contact with the parents of children who were in child restraints. In child restraint cases, the type of child restraint in use is identified and misuse or equipment failure is noted.

One of the leading causes of death and disability among young children is motor vehicle accidents. Although current child restraint systems (car seats) have significantly reduced mortality and morbidity, deaths and injuries still occur. Since it is not possible to correlate human child injury potential with the biomechanical devices used for high level impact testing using experimental methods, the acquisition and analysis of specific child injury data identifiable with real world automobile crashes is critical for input to biomechanical research, anthropometric test device (ATD) development and safety standard revisions. The purpose of this study was to analyze vehicular-related trauma that had occurred to children in known crash environments based on accident configuration and car seat design.

The automotive safety community has grown increasingly aware of the societal costs of injury impairment and disability resulting from automobile accidents. A significant portion of this impairment can be attributed to lower extremity trauma. An accident data study was conducted to determine lower extremity injury frequencies and mechanisms for restrained front-seat occupants in frontal collisions. A query of the 1988-1990 NASS (National Accident Sampling System) data provided information on pelvis, femur, knee, leg, and ankle and foot injuries. Age, gender, seating position, and delta-V were examined for their effect on the data. Lower extremity injury data were compared with injury data of similar severity (AIS ≥ 2) for the head, chest, thorax, and abdomen. The NASS data was supplemented with injury impairment information which, combined with anthropomorphic and biomechanical data, provides a prioritization scheme for the design of dummy lower extremities and instrumentation.

Lower limb injuries among motor vehicle occupants are relatively common and are one of the principle causes of permanent disability. The author has reviewed the current literature and his own experience as an orthopaedic surgeon and research accident investigator concerning lower limb injuries among motor vehicle occupants. An unreported series of knee, thigh, hip, pelvis injuries with indepth accident investigation is reported. Incidence rates for specific injury diagnoses are not available. Gross tabulations reveal that lower limb injury is second only to head injury in frequency among injured motor vehicle occupants. Lower limb injuries are possibly the commonest cause of permanent disability and impairment resulting from motor vehicle accidents.

Head-neck injuries occur frequently in pedestrian and occupant automotive accidents even at relatively low speeds. This paper describes the results of laboratory impact experiments using human cadavers in pedestrian/vehicle impacts and lateral-to-medial head impacts at well-known, controlled speeds. Cerebral trauma, with and without skull fracture, is discussed as a function of impact configuration and velocity. Cervical spine and cord injuries are also discussed with regard to the same parameters. Data presented include impactor mass and velocity, head acceleration measurements, complete autopsy and dissection results, and the clinical evaluation of the effect on a person of the observed trauma. Eighteen cadavers have been exposed to lateral-to-medial head impacts by two mechanisms.

The FMVSS were established to provide the public with uniform safety equipment and design standards based on sound research. Ongoing evaluation is essential to maintain the effectiveness and safety of FMVSS and to ensure that current technology is incorporated in standards development. Serious injury (AIS 3 or greater) reporting by NASS should be upgraded to facilitate standards evaluation and development. Although cost effectiveness is a mandated criteria for standards evaluation, the protection of human life and limb must remain the principle criteria for measuring effectiveness. A citizen's advisory panel, similar to the NMVSAC should be established to assist NHTSA in establishing priorities for standards evaluation, development and promulgation.

Development of a producible preloaded, force-limited passive belt restraint system for small cars has been completed at Calspan Corporation. The restraint system has been developed and evaluated through computer simulations and sled tests. This paper presents and discusses the results of the developmental program at velocity changes of 34, 40 and 45 MPH during symmetric frontal barrier crash sled and computer simulations with regard to the effect upon 50th, 95th, 5th percentile and 6 year old sized anthropometric test devices (ATDs). Data obtained include head and chest triaxial accelerations, femur loads and belt loads for the ATDs. High speed movies allowed comparisons of ATD kinematics during the sled tests with ATD model kinematics obtained from the computer simulations. A commercially available belt preloader was used during the sled tests along with: nylon webbing, polyester webbing and two levels of force limiting webbing.

Because of its flexibility and structure, the cervical spine is disposed to various mechanisms of injury: although not so common as injuries caused by head impacts, cervical fractures and/or fracture-dislocations have been reported without direct impact to the head. Some cervical injuries reported have been sustained by wearers of lap and shoulder belts in auto accidents; however, we do not consider belt use a potential hazard because ample evidence has accrued in the medical and engineering literature to document general injury and fatality reduction by use of seatbelts. We believe that in many instances occupants would be more seriously injured or killed were belts not worn. The present paper reviews reports of cervical injuries without head impact found in the literature and case histories of such injuries from the Highway Safety Research Institute of The University of Michigan, as well as experimental studies in animals, cadavers, and volunteer subjects.

Whiplash is a poorly defined term including ligamentous and muscle strains, hematomas, disc injuries, and less frequently, brain, eye and ear injuries. Diagnosis is difficult because clinical signs and Xrays, electromyography and electroencephalography findings are few. Protection and rest will cure most patients within a year but approximately 2/5th of patients have permanent symptoms and disability. Rear-end impact accidents cause the head and neck to hyperextend over the seat back. Whiplash occurs in 38% of exposed occupants. Head rests give protection but differential rebound may occur producing injurious hyperextension and whiplash. The larynx, trachea and esophagus, in front of the spine, are injured by impact against the dash or steering wheel. Airway obstruction may occur and cause death if not restored quickly. Permanent disability can occur because of scarring and partial airway or esophageal obstruction or vocal cord damage.

This paper presents an analysis of 67 neck injuries incurred in diving and sliding accidents in swimming pools. The accidents were investigated to establish the appropriate medical and mechanical factors involved. A mathematical model was developed to allow the prediction of the trajectory and velocity of the subjects prior to their injury. Nine of the accidents were selected for real life simulation. The simulation included the selection of test subjects of similar physical build to the accident victims who then performed the maneuvers leading to the injury, but in deeper water. High speed movies (200 frames per second) were taken, above and below the water, to measure the motion. A frame by frame analysis provided data to determine the trajectory and velocity profiles of the test subject. The maneuvers studied included diving from the pool edge, diving from various board types and sliding down various sliding board configurations.

Child restraint performance in frontal and lateral crash simulations is presented and discussed based upon tests conducted on the Calspan HYGE acceleration sled. Differing acceleration pulses for frontal tests were used to evaluate the pulse shape effect upon the child restraint systems. Two types of three year old size anthropometric test devices (ATDs) were used and restraint systems were intentionally improperly installed in an effort to ascertain the potential hazard to the child occupant from improper installation. Data obtained include head excursion, head and chest triaxial accelerations, Head Severity Index (HSI) and Chest Severity Index (CSI) values for the ATDs. High speed movie coverage produced dummy kinematic results.

Child restraint performance in frontal and lateral crash simulations is presented and discussed based upon tests conducted on the Calspan HYGE acceleration sled. Differing acceleration pulses for frontal tests were used to evaluate the pulse shape effect upon the child restraint systems. Two types of three year old size ATDs were used and restraint systems were intentionally improperly installed in an effort to ascertain the potential hazard to the child occupant from improper installation. Data obtained include head excursion, head and chest triaxial accelerations, HSI and CSI values for the ATDs. High speed movie coverage produced dummy kinematic results. Results of the study allow comparisons between the effects of different pulse shapes and the effects of different ATDs on restraint performance and comparisons in dynamic performance of the ATD/restraint complex under both proper and improper system installation.

An experimental program is discussed wherein fresh cadavera and anthropometric test devices (ATD) were exposed to identical crash situations utilizing both belt and air cushion restraint systems. Results will include symmetric and one-half offset frontal full size car-to-car tests conducted on the Calspan Vehicle Experimental Research Facility (VERF) at 60 MPH closing speed. Data obtained include head and chest triaxial accelerations from externally located sensors and thoracic accelerations from implanted sensors on the cadavera, normally measured internal triaxial head and chest accelerations and femur loads on the ATDs and belt loads for both cadavera and ATDs. Osteologic data allows comparison between the cadavera regarding their relative skeletal quality. Results of the study allow comparisons of the restraint systems effectiveness with respect to cadaver vs. cadaver and cadaver vs. ATD based upon autopsy evaluations and acceleration measurements.

An experimental program is discussed wherein fresh, unembalmed cadavers and anthropomorphic test dummies (ATD's) were exposed to identical crash situations. Results include tests conducted on the Calspan HYGE acceleration sled and full-scale car crash tests using belt restraint systems and air bag systems. Cadaver test data obtained include head and chest triaxial accelerations from externally mounted sensors, chest deflections and belt loads. Cadaver test data also include arterial and lung pressure measurements as well as X-ray and gross necropsy evaluations. Dummy test data include normally measured internal triaxial head and chest accelerations. High-speed movie coverage produced cadaver and dummy kinematic results. AT THIS TIME there exists some question in the automotive safety community as to the proper role cadaver experiments can play in the design, development and evaluation of safety related vehicle systems.

The basic physical mechanisms underlying recent experimentally observed anomalous behavior in the impact performance of safety helmets evaluated with soft (human-like) and hard (magnesium alloy) headform surrogates are qualitatively and quantitatively explained in this paper. The principal and physical mechanisms brought to light in the headform surrogate investigation are directly applicable to the utilization of other forms of surrogates (head -neck, thorax, whole body). In particular the results raise a serious question as to the validity of using non-human responding surrogates, with human generated injury tolerance data, for the purpose of assessing safety system performance. The implications of the results are that good crash-impact protective devices (helmets, restraints, etc.) could be penalized and, equally important, less safe crash-impact protective system designs could result from improper assessment of safety system performance.

All of the rear-end impact accidents occurring in the city of Rochester, New York, in a three-month period were surveyed by tabulation of the police accident reports. Special police information forms, telephone interviews, and mail questionnaires were used for further data acquisition. Vehicle photographs and medical examinations were conducted for approximately every 20th vehicle. During the data collection period, 691 rear-end impacts occurred. Although a computer program revealed 1371 accidents, defects in the program accounted for the large difference. Whiplash injury frequency based on telephone interview and mail questionnaire data obtained one to seven days after the accident revealed a whiplash injury frequency of 38%, which was approximately twice that determined by on-scene police investigators. Head restraints reduced whiplash frequency by 14% and fixed head restraints appeared to be more effective.

The Abbreviated Injury Scale (AIS) introduced in January 1968 has been widely used by the Medical Engineering Accident Investigation Teams of the NHTSA, by the General Motors ADAP, by the NATO Country Teams in Europe, and by the AMA Physician-Police Teams. The experience and problems involved in use of the AIS are reviewed. An extended and revised AIS has been developed. Validation studies revealed better than 80% accuracy by multiple users. The Comprehensive Research Injury Scale (CRIS) has been completed for all major medical specialties. The CRIS separates the various criteria (energy dissipation-ED, threat to life-TL, permanent impairment-PI, treatment period-TP, incidence-IN) used with variable quantities and frequencies in the AIS. The CRIS identifies and quantitates each scaling criteria permitting more meaningful and detailed application of the AIS.

This three-part paper deals with the medical aspects of driver protection in automobile racing. Part one presents the history of car safety equipment beginning with the development of helmets, belts, roll bars, and other devices to protect competition drivers. This paper describes the evolution from purely optional to mandatory equipment and how their design and accident records have contributed to increased safety in passenger cars. The investigation of injuries sustained in crash, fire, and loss of control caused by road hazards have contributed to the many improvements discussed here, almost all of which are readily adaptable to passenger car models. The second part presents a summary of the influence of racing on the design, testing and performance standards for protective headgear. The significance is indicated of applying basic principles of mechanics and dynamic systems testing to all fields in which head impact is a potential hazard.

Some 634 accidents occuring in races sanctioned by the Sports Car Club of America (SCCA) are reviewed. Shoulder harnesses were used in 275 of the accidents. Inverted “Y” or double, separately anchored, shoulder harnesses were used almost exclusively. A significant decrease in the frequency and severity of injuries occurred after harnesses were introduced. Injury from the restraint system was very infrequent; submarining occurred only once. Deep bucket seats, providing lateral support for the chest and forward support for the buttocks, appear to potentiate the effectiveness of restraint systems. The “Y” harness functions well in production seats without lateral support because lateral displacement of the shoulders and upper torso can occur without risk of neck injury.

A widely accepted injury scale is urgently needed by medical engineering automotive accident investigation teams. An informal committee of physicians, engineers and other researchers has developed two scales. The Abbreviated Injury Scale (AIS) combines and details several existing scales including the DeHaven-Cornell scale, the commonly used police scale, and others. Injuries which are usually not fatal are rated with a 1 to 5 scale. Several scaling criteria were combined but with varying weights to establish the AIS rankings. The Comprehensive Research Injury Scale (CRIS) was developed to separate the criteria used in injury scaling. Five separate criteria are used: Energy Dissipation (ED), Threat-To-Life (TL), Permanent Impairment (PI), Treatment Period (TP), and Incidence (IN). The ED scale ranks energy dissipation in injury production, and will be of major value to vehicle designers concerned with human tolerance for injury.