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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.

The objective of the study was to investigate the biomechanical response of the intact cranium. Unembalmed human cadavers were used in the study. The specimens were transected at the base of the skull leaving the intracranial contents intact; x-ray and computed tomography (CT) scans were obtained. They were fixed in a specially designed frame at the auditory meatus level and placed on the platform of an electrohydraulic testing device via a six-axis load cell. Following radiography, quasistatic loading to failure was applied to one of the following sites: frontal, vertex, parietal, temporal, or occipital. Retroreflective targets were placed in two mutually orthogonal planes to record the localized temporal kinematics. Applied load and piston displacement, and the output generalized force (and moment) histories were recorded using a modular digital data acquisition system. After the test, x-ray and CT images were obtained, and defleshing was done.

Head injury is a serious threat to lives of people working around farm machinery. The consequence of head injuries are costly, paralytic, and often fatal. Clinical and biomechanical data on head injuries are reviewed and their application in the analysis of head injury risk associated with farm tractor discussed. A significant proportion of tractor-related injuries and deaths to adults, as well as children, is due directly or indirectly to head injury. An improved injury reporting program and biomechanical studies of human response to tractor rollover, runover, and falls, are needed to understand mechanisms of the associated head injury.

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.

Results of child restraint system performance during dynamic testing of proper and improper installation configurations are presented and discussed. Over 75 frontal and oblique sled tests were performed using either an SA1001 six-month old infant size, an SA103C three-year-old toddler size or a VIP-6C six-year-old size dummy. Also included are results of sled tests of restraint systems (both commercially available and homemade/improvised) which are intended to protect larger size children. Data presented include head and knee excursions compared with available space in selected vehicles as well as head and chest accelerations and HIC values where applicable. High-speed movie coverage was used for the objective evaluation of dummy kinematics and the subjective evaluation of soft tissue loading and its injury-producing potential.

In a crash, impact against the steering assembly can be a major cause of serious and fatal injury to drivers. But the interrelationship between injury protection and factors of surface area, configuration, padding, relative position of the spokes, and number and stiffness of spokes and rim is not clear. This paper reports a series of high-G sled tests conducted with anesthetized animal subjects in 30 mph impacts at 30 G peaks. A total of eight tests were conducted, five utilizing pig subjects, one a female chimpanzee, one an anthropomorphic dummy, and one test with no subject. Instrumentation included closed circuit TV, a tri-axial load cell mounted between the steering wheel and column, seat belt load measurement, six Photo-Sonics 1000 fps motion picture cameras, and poloroid photography. Medical monitoring pre, during and post-impact was followed by gross and microscopic tissue examination.

Accurate data on the body dimensions of truck drivers are needed and such data are not presently available. This paper provides basic source data and an anthropometrical overview of the usefulness and limitations of existing data bases; discusses the influence of population factors, including age, sex, and demographic variables; and reviews population sampling problems. Heavy truck drivers as a whole appear to represent a physically different population from that of either the U.S. general population or other professional groups. Future anthropometric surveys must provide information for improved accommodation for the increasing range of physical size of users, and for obtaining data more useful to engineers involved in heavy truck interior cab design.

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.

Business and executive aviation represent a combined total of over 40% of the general aviation fleet, but (1977) accounted for only 8.37% of all general aviation accidents recorded. During the period 1964-1977 some 7,351 aircraft engaged in business flying, and 883 in corporate/executive operations, were involved in accidents reported by the NTSB. These accidents were reviewed utilizing the University of Michigan Computerized Accident Files to provide an overall view of the incidence and nature of business/executive aircraft accidents relative to occupant crash injuries. In addition more detailed case studies of selected accidents investigated including a Lear Jet 25B, Cessna 421, Beech Volpar Model 18, and Ted Smith Aerostar 601, are provided to illustrate specific types of crashworthiness, occupant protection, or post-crash emergency egress findings applicable to business/executive operations. Post-crash fire was reported in 29 cases (16.3%) during the 3-year period (1975-1977).

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.

Statistics indicate that during the past decade (1967-1976) the number of general aviation aircraft involved in an accident is equivalent to at least 38% of the total U.S. production during that period. Estimates that an aircraft will be involved in an accident over a 20 year life range are as high as 60-70%. Recognition of this probability has led to crashworthiness and occupant survivability “packaging” design concepts as offering the most realistic approach to reduction of serious and fatal injuries when an accident occurs. This paper reviews and illustrates current general aviation aircraft accident experience relative to occupant impact injury and damage indexes, and provides new data relative to current-generation aircraft.