| 1. |
- Antona, Jacobo, 1981, et al.
(författare)
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Correlation of Global Head and Brain Tissue Injury Criteria to Experimental Concussion derived from Monkey Head Trauma Experiments
- 2013
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Ingår i: IRCOBI Conference. - 2235-3151. ; :IRC-13-55, s. 509-522
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Konferensbidrag (refereegranskat)abstract
- A series of 24 frontal head traumatic impacts on macaques carried out in the past were simulatedwith a validated finite element model of the specimens. From these simulations, brain tissue response and headaccelerations were extracted. Based on the accelerations, global head injury criteria were calculated.Correlation between the brain tissue mechanical parameters, the global head injury criteria and the concussionscored in the experiments were analyzed. Based on this analysis, global head injury criteria that best correlatewith concussion score for frontal impacts were identified and injury risk functions for brain tissue that can beused for human FE models are proposed. In addition, the new results were compared to a previous study basedon simulations of 19 occipital head impacts from the same data source.
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| 2. |
- Antona, Jacobo, 1981, et al.
(författare)
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Reanalysis of Monkey Head Concussion Experiment Data Using a Novel Monkey Finite Element Model to Develop Brain Tissue Injury Reference Values
- 2012
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Ingår i: Proceeding of the 2012 International IRCOBI Conference on the Biomechanics of Impact. - 2235-3151. ; 2012, s. 441-454
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Konferensbidrag (refereegranskat)abstract
- A new method has been applied to develop a Finite Element (FE) model of the head‐ neck complexof Macaque monkey from medical images. The skull, brain and flesh have been validated based on tissue andcomponent experimental data from literature. The kinematics of the head during occipital impacts have beenvalidated against a sub‐set of head impact experiments carried out in the past at the Japan AutomobileResearch Institute (JARI). The validated model has been used to simulate 19 occipital impacts case‐by‐case. Thecorrelation between obtained peak values for a number of mechanical parameters of the different brain regionsand the occurrence of concussion in the experiments was analysed. Maximum principal strain in the brainstemshowed significant correlation to concussion; 21% strain was associated with a probability of 50% risk forconcussion. The developed model and the presented results constitute the first step towards the developmentof a tissue level injury criterion for humans that is based on experimental animal data.
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| 3. |
- Baker, Gretchen H., et al.
(författare)
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Comparison of Self-Selected, Holding Device, and Nominal Conditions on the Belt Fit and Posture of Children on Belt-Positioning Boosters
- 2023
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Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI. - 2235-3151. ; , s. 665-689
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Konferensbidrag (refereegranskat)abstract
- Children assume a range of postures when utilising belt-positioning boosters, which may influence belt fit and have implications for dynamic performance. This study evaluates the belt fit and posture of children on boosters while assuming different postures: self-selected, holding device, and nominal. Children (n=25) were recruited (4–11 years, 103.0–146.5 cm, 17.8–33.6 kg) and evaluated on two of five randomised boosters. A 3D coordinate measurement device and an inertial measurement unit-based motion capture system quantified posture, e.g., head, torso, and pelvis positions and orientations, and belt fit, e.g., shoulder belt score, lap belt score, maximum gap size, gap length. Outcomes were compared across postural conditions and boosters using repeated-measures ANOVA. The device condition produced significantly more forward and flexed head postures compared to self-selected and nominal (by 58 mm and 15.0° on average). Variation was small in terms of belt fit and belt gap metrics between postural conditions, suggesting that belt routing features provided similar belt placement despite postural adjustment; however, greater variation is expected in naturalistic settings. This study is the first to directly evaluate the posture and belt fit of children while holding electronic devices and to investigate the influence of different postural conditions on belt fit and postural outcomes.
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| 4. |
- Baker, Gretchen, et al.
(författare)
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Kinematics and Shoulder Belt Engagement of Children on Belt-Positioning Boosters during Emergency Braking Events
- 2017
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Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI. - 2235-3151. ; 2017-September:IRC-17-51
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Konferensbidrag (refereegranskat)abstract
- Emergency braking can influence children’s posture and seatbelt interaction. To better protect children in crashes preceded by emergency braking, this study a ims to quantify kinematics and seatbelt engagement during braking events . Eighteen rear‐seated children were exposed to braking events with 1 g deceleration in a passenger vehi cle, restrained by the seatbelt on a booster cushion and an integrated booster cushion. Vehicle acceleration and video data were analysed to m easure head displacement and shoulder belt position. On the booster cushion the belt was generally mid‐sho ulder and lower on the torso with a gap, while on the integrated booster cushion i t was closer to the neck and hi gher on the torso without a gap. Average forward head displacement was 160 mm on the booster cushion and 150 mm on the integrated booster cushion. Generally, the belt maintained the same position on the shoulde r throughout braking, with exceptions influenced by shifted initial positions or non‐standard motions. Braking e vents placed the head approximately 150‐190 mm forward from the initial position, influenced by booster, statu re, and initial seatbelt positioning. This reinforces the importance of maintaining mid‐shoulder or close to neck bel t positions and upright, centred postures prior to emergency braking, which may influence the likelihood of imp acting the vehicle interior and sustaining head injuries in a subsequent crash.
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| 5. |
- Brynskog, Erik, 1989, et al.
(författare)
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Population Variance in Pelvic Response to Lateral Impacts - A Global Sensitivity Analysis
- 2022
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Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI. - 2235-3151. ; 2022-September, s. 173-196
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Konferensbidrag (refereegranskat)abstract
- Pelvic fracture remains the third most common moderate to severe injury in motor vehicle crashes, and the dominating lower extremity injury in lateral impacts. An essential tool for analysis of injury, and real-world occupant protection, are finite element human body models. However, today's state-of-the-art pelvis models do not adequately consider the variability in shape and size naturally occurring in human populations. In this study, we developed a new detailed pelvis finite element model, morphable to enable representation of the population shape variance. The model was validated using force-displacement data from post-mortem human subjects, in lateral loading of the denuded pelvis, followed by a global sensitivity analysis. The results suggests that in lateral impacts to the pelvis, pelvic shape contributes to the model response variance by the same magnitude as pelvic bone material stiffness, and that each of these contributions are approximately twice that of the cortical bone thickness. Hence, to model pelvic response for a general population accurately, future studies must consider both pelvic shape and the material properties in the analysis. Increased knowledge about population variability, and inclusion in safety evaluations, can result in more robust systems that reduce the risk of pelvic injuries in real-world accidents.
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| 6. |
- Cutcliffe, Hattie, et al.
(författare)
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Gender differences in Occupant Posture during Driving and Riding
- 2017
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Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI. - 2235-3151. ; Antwerp, 2017, September 13-15:IRC-17-12, s. 23-33
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Konferensbidrag (refereegranskat)abstract
- The aim of this study was to compare postures of male and female vehicle occupants, tested in both front seat positions, during normal driving and deceleration onset. These data are useful for the development and initialisation of computational human body models. A secondary aim was to examine the effect of reversible, motorised seat belts in these events. Kinematics were analysed for volunteers driving on rural roads, prior to autonomous braking (11 m/s2 deceleration). Two restraint configurations were tested: a standard versus a motorized belt, activated 200 ms before braking initiation. Kinematic metric comparison via ANCOVA was performed to understand postural differences across gender, role (driver/passenger), and belt type (standard/motorised). Data was analysed prior to and at vehicle deceleration, termed typical riding and initial braking, respectively.While males and females displayed similar postures during typical riding, differences existed between driversand passengers, especially with respect to neck posture. Drivers displayed more protracted neck postures, withsignificantly smaller (by 22‐27 mm, depending on gender) head‐to‐sternum horizontal distances, than passengers.Motorised belts significantly changed posture during initial braking, notably of the chest (which was shiftedposteriorly by approximately 13 mm, depending on gender and role), while standard belts did not. Within a given belt type, occupants’ change in posture was similar across gender and role during initial braking.
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| 7. |
- Davidsson, Johan, 1967, et al.
(författare)
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Evaluation of Seat Performance Criteria for Rear‐End Impact Testing BioRID II and Insurance Data
- 2013
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Ingår i: IRCOBI Conference. - 2235-3151. ; :IRC-13-15, s. 63-76
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Konferensbidrag (refereegranskat)abstract
- The BioRID is recommended for legislative rear‐end impact seat tests. Recommendedinjury criteria are, however, lacking; biomechanical data are limited and confines any evaluation ofproposed criteria.This study aimed at addressing these limitations by comparing BioRID II data from sled tests withreal‐life accident data. Results will evaluate injury predictability of the complete sled test method, whichincludes performance criteria, the use of a generic acceleration pulse, and the BioRID, etc.Real‐life injury risk was calculated for 17 groups of similar seat designs from data provided byFolksam. The number of insurance cases range from 150 to 1136 per group. Regression coefficientswere calculated. Two types of injury risks were used: those leading to documented symptoms of morethan one month’s duration and those classified as leading to permanent medical impairment as aconsequence of a rear‐end impact. These risks were compared to parameter values from sled testsperformed with a BioRID II at 16 km/h pulses.NIC, the maximum rearward Occipital Condyle relative T1 x‐displacements and L1 x‐acceleration bestpredicted the risk of developing permanent medical impairment and symptoms of more than onemonth, given the occupant had initial symptoms following a rear‐end impact.
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| 8. |
- Davidsson, Johan, 1967
(författare)
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Volunteer Shoulder Range of Motion and Stiffness: Data for Evaluation of Crash Test Dummies and Human Body Models
- 2013
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Ingår i: IRCOBI Conference. - 2235-3151. ; :IRC-13-30, s. 230-244
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Konferensbidrag (refereegranskat)abstract
- The shoulder complex has low priority in the development of frontal impact crash test dummiesand Human Body Models. It is rarely exposed to injuries in frontal collisions but it does influence belt interactionand, as such, the thorax compression and head kinematics. Therefore, this study establishes responserequirements for the shoulder complex in terms of range of motion and stiffness.Six male volunteers were seated and belted, with minimum belt‐clavicle interaction, and shoulders werestatically loaded with increasing load; 0 ̶ 200 N/shoulder. Shoulders were pulled straight forward, forwardupward,upward and rearward. Three repetitions per direction were carried out.Resultant shoulder range of motion, at maximum loads, ranged from 44 to 73 mm. The volunteers providedmeasurements with reasonable repeatability.The applied loads were lower than those commonly seen in frontal crashes; however, the shoulder is highlymobile and its response is largely dependent on muscle characteristics. As such, these studies of volunteerresponses may be complimentary to tests with post mortem human subjects. Also, the volunteers curved theirspines only slightly in these tests. Hence, shoulder motion was successfully isolated and results reflect pureshoulder relative to chest motions. As such the data are suitable for dummy and Human Body Modelevaluations.
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| 9. |
- Elrud, Rasmus, et al.
(författare)
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Sickness absence among passenger car occupants following a Crash
- 2017
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Ingår i: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI. - 2235-3151. ; 2017-September, s. 79-90
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Konferensbidrag (refereegranskat)abstract
- Sickness absence is a common consequence of road traffic crashes, with high costs for the individual and society. Yet, scarcely studied, therefore, the aim was to describe sickness absence among injured car occupants. A population-based study using register data was conducted, including all car occupants of working age living in Sweden, who in 2010 had specialised in-or outpatient healthcare due to a car crash (n=9427). Individuals were categorised based on age, sex, and injury type. Odds ratios with 95% confidence intervals for a new sickness absence spell >14 days were estimated. After excluding the 9% already on sickness absence or disability pension, 10% had a new sickness absence spell >14 days. Sex and crash type were not associated with new sickness absence, while old age and being born outside Europe were associated with higher odds ratios. Odds ratios varied with the type of injury and injured body region. The odds ratio for sickness absence was highest for injuries to the spine and spinal cord odds ratio: 8.64 (95% confidence interval 6.45-11.57). Traumatic brain injuries except concussion had an odds ratio of 6.99 (4.04-12.08) while concussions had an odds ratio of 2.66 (1.80-3.93).
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| 10. |
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