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This study presents a design concept for a multi-configuration modular medical evacuation fixture that can be used to retrofit standard utility vehicles for emergency medical transport. The fixture has been designed so that when installed in a vehicle and configured for litter transport, it provides mounting structure for a single patient on a North Atlantic Treaty Organisation (NATO) style litter as well as for a variety of emergency medical equipment. When installed in a vehicle and configured for ambulatory patient transport, the device provides safe seating for multiple patients as well as mounting surfaces for medical equipment. When not installed, the fixture can be collapsed for ease of shipping and warehousing. A survey of potential host vehicles was conducted to evaluate the feasibility of the proposed design. Given a preliminary concept, factors such as expected patient anthropometry, and physical data of medical equipment were used to perform basic structural analyses.

Significantly, more fatalities and serious injuries occur due to ejection in roll over accidents. The present study was conducted to determine the occupant retention and head-neck injury potential aspects of laminated glass in roll over accidents. The head injury and neck parameters were obtained from Hybrid III 50% male dummy test device impacting on various types of side windows with laminated glass. Results indicated that the glass contained the dummy assembly and the head neck biomechanical parameters were below the critical value injury tolerance limits in simulated rollover accidents.

The prevention of lower extremity injuries to front seat car occupants is a priority because of their potential to cause long-term impairment and disability. To determine the types and mechanisms of lower extremity injuries in frontal collisions, studies under controlled test conditions are needed. Sled tests using belt-restrained cadavers and dummies were conducted, in which footwell intrusion was simulated via a plane surface or simulated brake pedal. Human cadavers in the age range from 30 to 62 years and Hybrid III dummies were used. The footwell intrusion had both translational (135 mm) and rotational (30 degrees) components. Maximum footwell intrusion forces and accelerations were measured. The lower legs were instrumented with accelerometers and a ""six axis'' force-moment transducer was mounted in the mid shaft of the left tibia.

Phase I, Phase II, Caterpillar, Allis-Chalmers, Clark, Hyster, Toyota, and Entwistle fork lift upset studies have been conducted with Hybrid II dummies, Side Impact Dummies, and stunt men. The investigations concluded that the dummy lacks the ability to brace itself, hold on, and does not have adequate biofidelity to represent the human in a fork lift upset. Crushing injuries and death typically occur when the operator is thrown or jumps from the overturning forklift and is pinned by the overhead guard or canopy. The dummy studies demonstrated a wide range of Head Injury Criteria (HIC) values that were not reproducible. Furthermore, other injury producing variables such as angular acceleration, angular velocity or induced brain stress were not investigated. The injury level of 1000 for the HIC for the mid-sized male, small female, and 6 year-old has been recommended by the National Highway Transportation Safety Administration (NHTSA).

Determination of human tolerance to injury is difficult because of the physical differences between humans and animals, dummies and cadaver tissue. Certain human volunteer testing has been done but at subinjurious levels [STAP 86] [EWIN 72] Considerable biomechanical engineering injury studies exist for the adult human cadaver however little is available for the pediatric population [SANC 99] [KLEI 98b]. Studies have been made of pediatric skull bone modulus, fetal tendon and early pediatric studies of the newborn during delivery, however, a paucity of information still exists in these areas. A number of dummies have recently been made available principally for airbag testing to bridge the gap between the 50 percentile Hybrid III male dummy and the 95 percentile male dummy.

The Federal Motor Vehicle Safety Standard 571.201 discusses occupant protection with interior impacts of vehicles. Recent rule making by the National Highway Traffic Safety Administration (NHTSA) has identified padding for potential injury reduction in vehicles. Head injury mitigation with padding on vehicular roll bars was evaluated. After market 2 to 2.5 cm thick padding and metal air gap padding reduced the head injury criterion (HIC) and angular acceleration compared to the stock foam roll bar padding. Studies were conducted with free falling Hybrid 50% male head form drops on the fore head and side of the head. Compared to the stock roll bar material, a nearly 90% reduction in HIC was observed at speeds up to 5.4 m/s. A concomitant 83% reduction in angular acceleration was also observed with the metal air gap padding. A 2 to 2.5 cm thick Simpson roll bar padding produced a 70 to 75% reduction in HIC and a 59 to 73% reduction in angular acceleration.

The purpose of this study was to investigate the use of the chestband in side impact conditions by conducting validation experiments, and evaluating its feasibility by conducting a series of human cadaver tests under side impact crash scenarios. The chestband validation tests were conducted by wrapping the device around the thorax section of the Side Impact Dummy at its uppermost portion. The anthropomorphic test device was seated on a Teflon pad on a platform to accept impact from the side via a pendulum system. Tests were conducted at 4.5, 5.7, and 6.7 m/sec velocities using round and flat impactors. Retroreflective targets were placed at each strain gauge channel on the edge of the chestband. The test was documented using a high-speed digital video camera operating at 4500 frames/sec. Deformation contours and histories were obtained using the chestband electronic signals in combination with the RBAND-PC software.

The paper describes an evaluation of impact performance requirements for pedal cycle helmets. The paper examines the results of two related studies, evaluates other helmet test results and proposes performance criteria more effective for the amelioration of head injury. The two main studies are of pedal cycle helmet performance in real accidents (McIntosh and Dowdell IRCOBI 1992) and head impact tests conducted under conditions relevant to those occurring during pedal cycle accidents (McIntosh et al Stapp 1993). The results of other helmet evaluations are drawn upon. The paper examines a number of areas of helmet performance and focuses on head coverage and impact test criteria. The results of the studies demonstrate that pedal cycle helmets are failing to provide adequate coverage in the temporal region, and that standards tests are not sensitive to this problem.

There exist two different methods to investigate the injury mechanisms and the tolerance levels, either sled tests or real road traffic accidents. Sled tests conducted at the University of Heidelberg and real accident cases examined by the University of Hannover were compared. The impact conditions of the Heidelberg sled tests were frontal collisions, with an impact velocity (Δv) of 50 km/h and decelerations of 10 g's to 20 g's. Twenty-nine tests with 3-point-belt protected cadavers in the age range 19 to 65 years were included in the Heidelberg collective. The Hannover sample contained 24 frontal accident cases (30 occupants) with a 100% overlap of the car front with the same Δv and average car deceleration range similar as the sled tests, the passenger compartment was only minimal intruded. Three-point belt protected drivers and front passengers in the age range of 18 to 71 years were included in the sample.

The number of passenger vehicles with combined 3-point belt/driver air bag restraint systems is steadily increasing. To investigate the effectiveness of this restraint combination, 48 kph frontal collisions were performed with human cadavers. Each cadaver's thorax was instrumented with a 12-accelerometer array and two chest bands. The results show, that by using a combined standard 3-point belt (6% elongation)/driver air bag, the thoracic injury pattern remained located under the shoulder belt. The same observation was found when belts with 16% elongation were used in combination with the driver air bag. Chest contours derived from the chest bands showed high local compression and deformation of the chest along the shoulder belt path, and suggest the mechanism for the thoracic injuries.

Sixty-three simulated frontal impacts using cadaveric specimens were performed to examine and quantify the performance of various contemporary automotive restraint systems. Test specimens were instrumented with accelerometers and chest bands to characterize their mechanical responses during the impact. The resulting thoracic injury severity was determined using detailed autopsy and was classified using the Abbreviated Injury Scale. The ability of various mechanical parameters and combinations of parameters to assess the observed injury severities was examined and resulted in the observation that belt restraint systems generally had higher injury rates than air bag restraint systems for the same level of mechanical responses. To provide better injury evaluations from observed mechanical parameters without prior knowledge of what restraint system was being used, a dichotomous process was developed.

The study reports on the results of frontal collisions with 16 cadavers and two Hybrid III dummies with impact velocities of 48 km/h to 55 km/h and a mean sled deceleration of 17 g; mounted to the sled was the front part of a passenger compartment. The cadavers were restrained in the driver position with either 3-point belts (6% and 16 % elongation) and/or air bag with knee bolster and one case was unrestrained. In most cases, both a 12-accelerometer thoracic array and 2 chest bands were employed. In some cases the acceleration at Th6 was measured. The cadavers were autopsied and the injury severity was rated according to the AIS 90. Maximum resultant Th1, Th6, and Th12 accelerations or sternum accelerations in x-direction ranged from 35g to 78g when using 3-point belts and produced injuries ranging from a few rib fractures to unstable chest wall (flail chest).

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.

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.

In the present investigation a tractor wheel runover accident was simulated to obtain biomechanical information relating to mechanism of injury. Twelve cadaver porcine specimens were runover with the right front wheel of a tractor. Specimens were placed on a six-axis force plate and thorax contours were recorded temporally. Results indicated up to 68% compression of the chest occurred during the runover event. The shear force in the direction of travel was a significant factor in the type of fractures that occurred to the rib cage. Pathology determined from x-ray revealed multiple fractures per rib in the area directly below the path of the tire. Autopsy evaluation revealed soft tissue contusion on the left side in the area of wheel path. There was often extra blood in the pericardial space and examination of the brain showed petechial hemorrhaging subdurally.

This paper documents seven car/car lateral collisions with belted farside rear seat occupants. The test subjects - cadavers and US SIDs - were restrained with a 3-point belt which had an inboard upper anchoring point for the shoulder belt. The collision velocity was 50 km/h. In the cadaver tests, the maximum resultant acceleration, an average of 18 G, was located at the clivus. In the US SID a maximum of 22 G occurred at the C.G. Average shoulder belt forces in the cadavers of 1,6 KN were measured compared to 2,5 KN in the US SID. Through an analysis of the high speed films, lateral head-neck bending angles of 40 to 65 degrees for the cadavers were investigated. The calculated angular velocities were between 13 and 38 rad/s and angular accelerations between 350 and 644 rad/s2. No head, thorax or pelvic injuries were observed. Belt-induced minor injuries at the skin on the neck, neck muscles and cervical spine were observed with a MAIS 1.

The patho-anatomic alterations due to vertical loading of the human cervical column were documented and correlated with biomechanical kinematic data. Seven fresh human cadaveric head-neck complexes were prepared, and six-axis load cells were placed at the proximal and distal ends of the specimens to document the gross biomechanical response. Retroreflective markers were placed on bony landmarks of vertebral bodies, articular facets, and spinous processes along the entire cervical column. Targets were also placed on the occiput and arch of C1. The localized movements of these markers were recorded using a video analyzer during the entire loading cycle. Pre-test two-dimensional, and three-dimensional computerized tomography (CT), and plane radiographs were taken. The specimens were loaded to failure using an electrohydraulic testing device at a rate of 2 mm/s.

Engineering efforts directed at better occupant safety require a thorough understanding of available epidemiologic data. Epidemiologic studies using clinical as well as accident information facilitates the prioritization of biomechanics research so that controlled laboratory experimentation and/or analytical models can be advanced. This information has also value in dictating levels and types of injury that are critical to the development of anthropomorphic test devices used in crash environments. In this paper, motor vehicle accident related (excluding pedestrians, bicyclists, and motorcyclists) epidemiologic data were obtained from clinical and computerized accident (National Accident Sampling System-NASS) files. Clinical data were gathered from patients admitted to the Medical College of Wisconsin Affiliated Hospitals, and fatalities occurring in Milwaukee County, State of Wisconsin. NASS database with specific focus on spinal injuries of motor vehicle occupants was also used.

Results from 15 side impact tests with EUROSID are reported and compared with results from 58 postmortem human subjects (PMHS). In this test series a CCMC moving deformable barrier impacted an Opel Kadett body in white under a 90° impact angle. Impact speeds were 40 km/h, 45 km/h, 50 km/h. The main goal of this research project was to find out to what extent the EUROSID is able to predict injuries which were obtained under identical test conditions using PMHS. Statistical methods described in former publications were used to calculate prediction relations derived from measured data. The body regions to be concentrated on according to PMHS tests were thorax, abdomen, and trunk of the EUROSID. Measurements taken on the dummy indicated major problems regarding interpretation of results: in some tests rib deflection was higher with 40 km/h than with 50 km/h. The abdominal switches frequently indicated high forces at 40 km/h impact speed whereas they did only once at 50 km/h.

The paper presents a report about car pedestrian impact simulations. The front of a production car, which was mounted on a platform moving on rails was used as impact vehicle. The test subjects were eleven unembalmed post mortem human subjects (PMHS) in the age range of 19 to 78 years, and the Hybrid II-P dummy. The test speeds ranged from 23 to 41 km/h. Accelerations of head, thorax and abdomen were measured on the test subject as well as at the inside of both the knee and the ankle of the impacted leg. High speed films were taken from the side view. In eight cases we noticed open tibia and fibula fractures of the impacted leg; usually associated with higher impact velocity or the age of the test subject; in one additional case a scapular fracture occurred at a collision velocity of 41 km/h. In 6 cases we observed vertebral column injuries of AIS 1, in two cases of AIS 2, and in one case of AIS 3. In no case did pelvic-, thoracic (skeletal) and skull fractures occur.