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This study focused on occupant responses in very large pickup trucks in rollovers and was conducted in three phases.Phase 1 - Field data analysis: In a prior study [9], 1998 to 2020 FARS data were analyzed; Pickup truck drivers with fatality were 7.4 kg heavier and 4.6 cm taller than passenger car drivers. Most pickup truck drivers were males. Phase 1 extended the study by focusing on the drivers of very large pickup trucks. The size of 1999-2016 Ford F-250 and F-350 drivers involved in fatal crashes was analyzed by age and sex. More than 90% of drivers were males. The average male driver was 179.5 ± 7.5 cm tall and weighed 89.6 ± 18.4 kg.Phase 2 – Surrogate study: Twenty-nine male surrogates were selected to represent the average size of male drivers of F-250 and F-350s involved in fatal crashes. On average, the volunteers weighed 88.6 ± 5.2 kg and were 180.0 ± 3.2 cm tall with a 95.2 ± 2.2 cm seated height. The volunteers were lap-shoulder belted in the driver seat of a 2002 Ford F-250 crew cab. The head-to-roof clearance was 12.8 ± 1.1 cm. It was 1.0 ± 0.6 cm once the vehicle was statically inverted.Phase 3 – Drop tests: Three drop tests were conducted using 2002 Ford F-250 crew cab pickups. An instrumented 50th Hybrid III ATD was lap-shoulder belted in the driver seat. The ATD was modified by increasing the seated height by 5 cm, from 88 to 93 cm, to represent the average driver of very large pickups. Biomechanical responses were assessed. All were below Injury Assessment Reference Value (IARV) except for upper and lower neck. The effect of roof/pillar deformation on occupant responses was analyzed by varying the vehicle weight (3147 kg in production test v 1502 kg in the buck test) and roof/pillar strength (production v roll caged). The test data and videos were reviewed to identify time coinciding with ground contact, head-to-roof contact, peak biomechanical responses, and maximum deformation. Upper neck compression was -7,426 N in the production test; it was -8.339 N in the buck test and -7,549 N in the roll caged tests. The loads occurred at about 25 msec in all tests. Maximum roof/pillar deformation occurred 150 ms later in the production test.Conclusion: Peak neck compressions were similar in the three tests and occurred shortly after initial head contact and prior to significant roof/pillar deformation. Neck injury responses resulted from torso augmentation and were independent of roof system deformation.

This study analyzes field accidents to identify rear-occupant exposure and injury by crash types. Occupant demographics and injury were assessed by body region and crash severity to understand rear-occupant injury mechanisms in rear crashes.The exposure and serious-to-fatal injury was determined by crash type for non-ejected second- and third- row occupants in 1994+ MY vehicles using 1994-2015 NASS-CDS. Selected occupant demographics and serious injury distributions were assessed over a range of delta V for rear crashes.Rear crashes accounted for 8.7% of exposed and 5.4% of serious-to-fatally injured rear-seat occupants. On average, rear-seat occupants were 14.3 ± 1.5 years old (median 10.3, 90The height and weight of a 10-year old and 5

Identifying the prevalence of degenerative spinal pathologies and relevant demographic risk factors is important for understanding spine injury risk, prevention, treatment, and outcome, and for distinguishing acute injuries from degenerative pathologies. Prevalence data in the literature are often based on small-scale studies focused on a single type of pathology. This study evaluates the prevalence of diagnosis of selected degenerative spinal pathology diagnoses using Medicare insurance claim data in the context of published smaller-scale studies. In addition, the data are used to evaluate whether the prevalence is affected by age, sex, diagnosed obesity, and the use of medical imaging. The Medicare Claims 5% Limited Data Set was queried to identify diagnoses of degenerative spinal pathologies. Unique patient diagnoses per year were further evaluated as a function of age, gender, and obesity diagnosis. Participants were also stratified by coding for radiological imaging accompanying each diagnosis. The overall prevalence of diagnosed spinal degenerative disease was 27.3% and increased with age. The prevalence of diagnosed disc disease was 2.7 times greater in those with radiology. The results demonstrate that degenerative findings in the spine are common, and, since asymptomatic individuals may not receive a diagnosis of degenerative conditions, this analysis likely underestimates the general prevalence of these conditions.

Intrusion of the occupant compartment increases the risks for severe injury and death. This study analyzes rear sled and crash tests with an instrumented second-row Hybrid III 5th percentile anthropometric test device (ATD) to assess occupant kinematics and biomechanical responses with and without intrusion of the second-row seatback. Three sled tests and four crash tests were conducted with a 1993 Ford Taurus and a belted 5th female ATD seated behind a belted 50th male ATD on the right-side of the vehicle. The sled tests were conducted at 25, 33 and 40 km/h and involved no intrusion. The first crash test was conducted with a passenger car striking the vehicle at 80 km/h with full centerline overlap. The second to fourth crash tests were with a Sport Utility Vehicle (SUV) striking with a 50% overlap. Tests 2 and 3 were at 51 km/h and test 4, at 80 km/h impact speed. A large wooden speaker box was placed in the trunk of the Taurus in tests 3 and 4. Second-row intrusion was measured at the right-rear outboard package shelf retractor. The sled tests without intrusion had occupant responses below injury assessment reference values (IARVs). The right second-row ATD moved rearward relative to the interior, compressing the rear seatback until it rebounded forward. Occupant compartment intrusion of 12–77 cm in the crash tests pushed the ATD forward, increasing head and chest acceleration. The head, neck and chest biomechanical responses were below IARVs in crash tests 1 to 3 with minimal intrusion (≤ 25 cm). Most of the biomechanical responses were above IARVs for the right second-row ATD in test 4 with higher intrusion. The HIC increased with intrusion. Head acceleration was more than 2.5-times greater in test 3 than in test 2, highlighting the importance of cargo in rear crashes. Test 4 had 2.4-times more energy than test 3 and up to 7.7 times greater biomechanical responses with 77 cm of intrusion. The crash tests show that intrusion increases occupant responses in the right second-row seat and pushes the occupant forward in rear impacts. The sled tests without intrusion had relatively low biomechanical responses. Intrusion was influenced by the crash energy and cargo.

This study was conducted to assess the effects of differing rear impact pulse characteristics on restraint performance, front-seat occupant kinematics, biomechanical responses, and seat yielding. Five rear sled tests were conducted at 40.2 km/h using a modern seat. The sled buck was representative of a generic sport utility vehicle. A 50th percentile Hybrid III ATD was used. The peak accelerations, acceleration profiles and durations were varied. Three of the pulses were selected based on published information and two were modeled to assess the effects of peak acceleration occurring early and later within the pulse duration using a front and rear biased trapezoidal characteristic shape.The seatback angle at maximum rearward deformation varied from 46 to 67 degrees. It was lowest in Pulse 1 which simulates an 80 km/h car-to-car rear impact. The seatback plastic deformation was greater in the pulse with the rear biased trapezoidal acceleration profile, Pulse 4, than in the front biased trapezoidal acceleration profile, Pulse 5 (46 degrees v 41 degrees). Coincidingly, the longitudinal head displacement was slightly greater in the Pulse 4. There was limited relative motion between the ATD torsos and the seatbacks. The relative motion between the ATD torso and the seatback was less than 7 cm in all tests. The head, chest and pelvis peak acceleration and timing varied depending on the pulse. All peak head, chest, pelvis and upper and lower-neck moments occurred prior to maximum seatback dynamic deflection. The biomechanical responses were all well below injury assessment reference values. The seatback structural restitution was the highest in Pulse 1 which had the lowest amount of dynamic and plastic seatback deformation and had the highest lap belt load. All peak belt loads occurred in the rebound phase of the ATD.The sled coordinate-based data was used to determine the effective restraint stiffness. The results were used to develop a spring-mass model. The model will help understand the effects of pulse characteristics on predicted chest acceleration for future research.In conclusion, the results from this study show that pulse shape has a measurable effect of seat and ATD kinematics in high-speed rear impacts and should considered for future research and testing.

Prior to developing or modifying the protocol of a performance evaluation test, it is important to identify field relevant conditions. The objective of this study was to assess the distribution of selected crash variables from rear crash field collisions involving modern vehicles. The number of exposed and serious-to-fatally injured non-ejected occupants was determined in 2008+ model year (MY) vehicles using the NASS-CDS and CISS databases. Selected crash variables were assessed for rear crashes, including severity (delta V), impact location, struck vehicle type, and striking objects. In addition, 15 EDRs were collected from 2017 to 2019 CISS cases involving 2008+ MY light vehicles with a rear delta V ranging from 32 to 48 km/h. Ten rear crash tests were also investigated to identify pulse characteristics in rear crashes. The tests included five vehicle-to-vehicle crash tests and five FMVSS 301R barrier tests matching the struck vehicle.The analysis of NASS-CDS and CISS data indicates that more than 50% of exposed (MAIS 0+F) occupants were involved in a rear crash with a distributed impact and with no over-ride or under-ride. More than 93% were with a 6 o’clock PDOF. The average rear delta V was 21.3 ± 1.2 km/h (median 18.2, 90th CI 9.7-33.4) in the exposed (MAIS 0+F) occupant sample. For serious-to-fatally (MAIS 3+F) injured occupants, more than 88% were in a fully distributed rear impact and in 6 o’clock PDOF; 10.7% were in offset impacts and less than 1% were in narrow impacts. The average delta V was 35.9 ± 5.2 km/h (median 24.4, 90th CI 16.2-58.3) for serious-to-fatally (MAIS 3+F) injured occupants.The results from the field data suggest that rear impacts with a delta V of 34-38 km/h and a 6 o’clock PDOF are representative of the average rear-crash scenario causing serious-to-fatal injury. Compared to the exposed occupants in the field data analysis, a 40 km/h rear sled is more than 1.9-times more severe than the average rear impact crash severity in terms of delta V and 4.4-times more severe in terms of crash energy. It is 1.11-times more severe than the average delta V for the serious-to-fatally (MAIS 3+F) injured occupant. It accounts for more than 90% of all occupants with injury (MAIS 1+F).EDR data was helpful in accessing overall delta-V and impact duration information. For example, the average delta V in the EDRs included in the analysis was 38.7 ± 7.6 km/h and the average pulse duration was 129.6 ± 24.3 ms. Instrumentation data from crash tests provided more refined information for a detailed analysis of pulse characteristics.The acceleration data obtained from the five vehicle-to-vehicle crash tests was investigated and compared to matched FMVSS 301 tests with the same struck vehicle. The data was scaled to a 40 km/h delta V pulse for comparison purposes. Bi-modal pulse shape characteristics were observed. The peak acceleration averaged 18.4 g in the vehicle-to-vehicle tests and 21.4 g in the FMVSS 301R tests. The average pulse duration was 147.2 ms and 123.8 respectively.The results from this study suggest that using a 34-40 km/h bimodal-rear pulse with a 130-160 ms duration is representative of a serious real world rear impact.

Occupant kinematics and biomechanical responses are assessed with and without pretensioning of normally seated and out-of-position front-seat occupants in rear sled tests. The results are compared to recent studies.Three series of rear sled tests were conducted at 24 and 40 km/h with a 2001 Ford Taurus. Series I consisted of two sled tests with a lap-shoulder belted 50The ATD kinematics and biomechanical responses were similar in the yielding phase when the occupant was normally seated with and without pretensioning. The rebound displacement was greater with pretensioning in the 40 km/h tests due to the shoulder belt slipping off the shoulder. The hip displacement was similar, irrespective of pretensioning. All biomechanical responses were below IARVs. The highest response was for lower neck extension. The normalized response was at about 32% for the 24 km/h tests, irrespective of pretensioning. It was up to 59% in the 40 km/h tests with pretensioning. With the OOP occupants, there were no differences in the kinematics and biomechanical response with pretensioning.Testing of the effect of retractor pretensioning with out-of-position occupants and additional belt webbing in moderate to high-speed rear sled tests shows no effect on occupant kinematics and biomechanical responses. The displacement of the hips in a rear impact depends on the compliance of the seatback and amount of pocketing, the stiffness of the seat frame limiting rearward rotation, and the dynamic friction between the occupant and the seatback.

This study compared dummy kinematics and biomechanical responses with and without retractor pretensioning in a severe rear sled test. It compliments an earlier study with buckle pretensioning.Three rear tests were run at 40 km/h (25 mph) delta V with a lap-shoulder belted Hybrid III 50The dummy kinematics and biomechanical responses were essentially similar with and without retractor or retractor and anchor pretensioning in rear sled tests. There was an initial spike in lap belt load with pretensioning, but it did not result in different dummy head, neck or chest responses. In the tests, the dummy moved rearward away from the shoulder belt. The belts were tightened with the rapid pull on the webbing by pretensioning. The dummy loaded the seat, which yielded rearward restraining its motion. There was no significant effect of pretensioning on the dynamics of the dummy until late in rebound.There were no significant differences in dynamics of the Hybrid III with and without retractor or retractor and anchor pretensioning in a 40 km/h (25 mph) rear sled test. Belt pretensioning did not influence biomechanical responses in the rear impact because the seat supported the dummy.

The purpose of this study was to examine the impact of the nationwide response to passenger airbag (PA) related deaths of children. The response was implemented in 1996 and focused on moving children to rear seats. This study determined the change in seating position of children from 1989 to 2019.Field accident data on exposed occupants in towaway crashes was determined using 1989-2015 NASS-CDS in five groups (1989-1995, 1996-99, 2000-04, 2005-09 and 2010-15) and 2017-19 CISS in one group. Children were grouped as 0-2 yo (years old), 3-7 yo and 8-12 yo. Occupants 13 + were included for completeness. Seat position was defined as left-front (LF), right-front (RF), 2nd row and 3rd row. The weighted data provided an estimate for the change in seating position over time by occupant age with standard errors.For 0-2 yo, 27.9% were in the RF seat in 1989-95. The fraction decreased to 0.40% in the 2017-19 (p 0.001). For 3-7 yo, 32.1% were in the RF seat in 1989-95 and 3.2% in 2017-19 (p 0.001). There has been a steady decrease in 0-7 yo using the RF seat. For 8-12 yo, there was a step decline in use of the RF seat from 39.5% in 1989-95 to 23.2% in the 2017-19 (p 0.001).The immediate reduction in front-seat use among younger children was associated with the nationwide public information efforts implemented in 1996 to move children to rear seats. Children up to 7 yo are no longer riding in the RF seat of vehicles in towaway crashes, unless there is no other option. Children 8-12 yo are still using the RF seat, but at a lower rate. The change in use of the RF seat for children 0-7 yo provides evidence that safety campaigns on placing young children in rear seats were successful in the US.

This study addressed the potential effect of higher seat stiffness with ABTS (All-Belt-to-Seat) compared to conventional seats in rear impacts. It analyzed field accidents and sled tests over a wide range in delta V and estimated the change in number of injured occupants if front-seats were replaced with stiffer ABTS.The rear-impact exposures and serious-to-fatal injury rates were determined for 15+ year old non-ejected drivers and right-front passengers in 1994+ model year vehicles using 1994-2015 NASS-CDS. More than 50 rear sled tests were analyzed using conventional and ABTS seats. An injury risk was calculated for selected ATD biomechanical responses. The results obtained with the ABTS and conventional seats were compared for matched tests based on head restraint position, ATD size and initial position and delta V. The change in risk was used to estimate the change in injury in the field by adjusting the injury rate by delta V.On average, front seat occupants were 39 years old, weighed 78 kg and were 171 cm tall. About 29.3% of serious-to-fatally injured (MAIS 3 + F) front seat occupants were involved in delta Vs less than 24 km/h and about 28.4% in a delta V of 48 km/h or greater. The average biomechanical response and injury risk in sled tests were higher with an ABTS seat than with a conventional seat. The average maximum injury risk was assessed by delta V groups for conventional and ABTS seats. The relative risk of ABTS to conventional seats was 1.34 in less than 16 km/h, 1.69 in 16-24 km/h, 1.65 in 24-32 km/h, 1.33 in 32-40 km/h, 5.77 in 40-48 km/h and 48.24 in the 56-64 km/h delta V category. The estimated relative risk was 11.90 in 48-56 km/h and 34.11 in 64+ km/h. The number of serious-to-fatally injured occupants was estimated to increase by up to 6.88-times if stiffer ABTS seats replaced conventional seats.The field data indicate that the 50

Rear occupant protection in rear crashes is a complex issue. Structural intrusion has been shown to be a significant factor in the injury mechanism of second-row children. In this study, a new model was developed to help quantify dynamic second-row intrusion, in terms of displacement, velocity, and acceleration, and assess its effect on rear occupant responses as a function of time. A mathematical model was developed using crash test data based on two reconstructed field accidents involving two different rear-ended vehicles with second-row children. The model also used the corresponding FMVSS 301R-type rear barrier tests of a similar vehicle. The crash test pulse data and videos from FMVSS 301R-type tests were analyzed to determine the timing and magnitude of second-row intrusion. Crash tests that had been conducted to simulate the field accidents were then used to validate the model. These tests included instrumented ATDs (Anthropometric Test Device) seated in the second-row area of the struck vehicles. The biomechanical responses were used to assess the validity of the mathematical model. Comparison between the mathematical model and the test data showed good agreement. For example, the model correctly showed that the dynamic second-row intrusion was greater than residual/static intrusion/displacement. The model also predicted accelerations that were in good agreement with the test data. Video analysis and head/chest acceleration time histories of the ATD’s indicated that intrusion occurred early and was an important factor in the occupant responses. Both the extent and velocity of dynamic intrusion also influenced the biomechanical responses. The model predicted head and chest accelerations that were greater than the overall vehicle accelerations due to localized structural intrusion. The mathematical model developed in this study is a first to assess the dynamic effect of second-row intrusion on rear occupant responses. Identifying factors that influence injury mechanisms are important when assessing the potential effectiveness of countermeasures.

Objective: To report the occurrence of a giant left adrenal tumor and bilateral testicular masses (adenomatous hyperplasia of Leydig cells) in a young man with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Methods: The clinical, radiologic, endocrinologic, and pathologic features of this case are correlated with the findings in the literature. Results: The interesting elements in this case are the rare pathologic features of the left adrenal lesion (pigmented adrenal hyperplasia with myelolipomatous changes) and the association with the infrequent testicular adrenal rest tumors. The absence of enlargement of the right adrenal gland was unexplained. Conclusion: The presence of these two rare complications seemed to be associated with poor adherence to medical treatment recommendations for congenital adrenal hyperplasia. (Endocr Pract. 2000;6:260-263)

The airborne phase of a rollover is studied to: quantify the effect of restraint anchor locations and belt component designs in reducing head excursion; and to better correlate the response between humans and an anthropometric test device (ATD) during the high angular roll rate of the airborne phase rollover. Comparison of results from human volunteers, cadaveric and Hybrid III ATD subjects in static tests indicate that the Hybrid III ATD had the least vertical excursion.