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The effect of striking compliance in ice hockey impacts, and its influence on dynamic response and brain tissue strain was investigated in this study. In hockey, players can experience a broad range of striking/surface compliance during a head impact, from the stiff ice surface to highly compliant player collisions. An increase in striking compliance has been shown to extend the duration of an impact that is associated with an increase in risk of sustaining brain injuries. Three striking caps of low, medium, and high compliance were used to impact a helmeted 50th percentile Hybrid III male headform attached to an unbiased neckform. Each level of compliance was used to impact five high risk locations at three different velocities, representative of head impact scenarios in ice hockey. The dependent variables, peak resultant linear accelerations and peak resultant rotational acceleration as well as MPS, were analyzed using a multivariate analysis of variance (MANOVA) to determine if there were significant differences between the three controlled variables. The results demonstrate a significant effect of compliance, over the influence of velocity and acceleration. Conditions of low impact compliance resulted in higher response values compared to impacts of increased compliance. That being said, high compliance conditions remained in the range of concussion risk, even at the lowest velocity. The use of brain tissue modeling, compared to dynamic response alone, demonstrated an elevated risk of brain injury as a result of extended impact durations. Impact compliance in hockey is a factor that has not been considered when designing and testing helmet technology. The results of this study demonstrate that compliance is a determining factor in producing brain injury, and should be incorporated into helmet standard testing to mitigate risk. The results of this study have implications on brain injury risk that extend beyond the impacting scenarios of ice hockey. The results can be extrapolated to any contact sport that includes impacting scenarios against varied impacting compliances such as football and rugby.

In Taiwan, a motorcycle is the most important and general transportation. It is no denying that wearing a motorcycle helmet could prevent the rider from head injuries in the accidents. However, the ventilation of helmets still has to be improved. This study aims to set several ventilation channels in the energy absorption liner. They apply the Venturi effect to increase the ventilation of helmets. But it may affect the protection performance of helmet. The purpose of this study is to estimate the protective ability of the ventilative helmet. Therefore, the various ventilative helmets are designed by the computer-aided design software SolidWorks, and simulations of the impact test of the helmet are investigated by the finite element analysis software ANSYS/LS-DYNA. In addition, the effect of using different foam material is also discussed in this study.

No description available.

Ice hockey helmets effectively mitigate the risk of skull fractures and focal traumatic brain injuries in professional ice hockey (PIH), but do not manage diffuse brain injuries such as concussion. This is due to current standard tests, which only represent one head impact event (a fall to the ice) and do not measure rotational head kinematics. It is important that helmets are evaluated using impact conditions that represent how players sustain concussions in ice hockey. The objective of this study was to describe the relationship between three ice hockey helmet tests and reconstructions of three concussive injury events in PIH. A flat anvil drop test (representing head-to-ice impacts), angled anvil drop test (representing head-to-boards impacts at 30o and 45o) and pneumatic ram test (representing medium and high compliance shoulder-to-head impacts) were performed using parameters reflecting concussive injuries in PIH. Stepwise regressions identified the dynamic response variables producing the strongest relationships with MPS. For the flat anvil drop test, dominant linear acceleration had the strongest relationship with MPS (R2 = 0.960), while there were no significant predictors of MPS from the PIH head-to-ice reconstructions. Rotational velocity had the strongest relationship for the 30o (R2 = 0.978) and 45o Anvil Drop Tests (R2 = 0.977), while rotational acceleration had the strongest relationship for the PIH head-to-boards reconstructions (R2 = 0.649). Resultant rotational acceleration had the strongest relationship for the medium compliance ram test (R2 = 0.671), the high compliance ram test (R2 = 0.850) and the PIH shoulder-to-head reconstructions (R2 = 0.763). The flat anvil drop test results indicate that falls on a flat, rigid surface induce primarily linear acceleration of the head. Standards should continue using this type of test to ensure helmets prevent skull fracture and focal TBI. Ice hockey helmets should also be evaluated using an angled anvil drop test and a collision ram test, representing two unique head impact events known to cause concussive injuries. The 45o Anvil Drop Test provided a closer representation of concussive head-to-boards impacts in PIH, with rotational velocity producing the strongest relationship with MPS. For collision impacts, the Medium Compliance Ram Test yielded repeatable impact conditions while the High Compliance Ram Test provided a closer representation of real-world concussive shoulder-to-head impacts. For these pneumatic ram tests, rotational acceleration produced the strongest relationship with MPS. The information in this thesis may be used by standards organizations when designing future ice hockey helmet tests.

Graduation date: 1997

No description available.

Introduction and Rationale: Bicycle riding is popular among the pediatric population, but with popularity comes a significant increase in morbidity and mortality. Cycling injuries occur in one-fifth of children aged 15 years and younger. Most life-threatening injuries among bicycle riders occur when the head is involved in bodily injury. Traumatic brain injury (TBI) related to bicycle accidents accounts for three-fourths of deaths. Despite the risk, many bicycle riders go without wearing helmets, largely due to lack of ownership. Purpose and Objective: The purpose of this Doctor of Nursing Practice (DNP) project was to develop and implement a pilot bicycle helmet program for a pediatric population, ages 5-13, from a pediatric emergency department (PED) perspective. The project objective was to increase bicycle helmet use among participants' children by providing the child with a free bicycle helmet, and also providing the parent with education specifically related to the importance of bicycle helmet safety. The project was driven through the Health Belief Model, and utilized the Teachable Moment of a PED encounter to influence risk-reducing behavior. Methods: This DNP project utilized a quasi-experimental, one group, pre- and post-test design. Participants were recruited from an urban PED, and identified at triage as being involved in a bicycle accident. Eligible children were fitted for a free bicycle helmet, and the parent was provided with an educational session coupled with a handout for home. A one-month follow-up phone call was conducted to assess bicycle helmet use and education retainment following the intervention. Results: All participants reported an increase in bicycle helmet use by their children. This study was able to show statistical significance related to bicycle helmet use, thus the null hypothesis was fairly confidently rejected. However, there were only five participants in this study, which makes generalization of results to a larger population difficult. Conclusions: This study showed that a bicycle helmet program is feasible in a PED, and could increase bicycle helmet use in a pediatric population. A DNP is an excellent candidate to run such a program as it focuses on positively impacting injury-prevention and dissemination of good practice for a larger community.

Background: From the perspective of what is called "vision zero" in Sweden, fatalities and injuries among bicyclists are unacceptable. Despite that, bicyclists constitutes approximately one third of all road user inpatients in Swedish hospitals, which is about the same proportion seen for drivers and passengers of motor vehicles. There are too many bicycle-related head injuries, but the risk of such traumas could be reduced considerably by the use of helmets. Bicycle helmet wearing can be increased by voluntary means, for instance by long-term community-based helmet promotion programs. However, the best effect has been achieved by combining promotion with a compulsory helmet law for all bicyclists, as has been done in Australia, New Zealand, and North America Aim: The general aim of the research underlying this dissertation was to provide further information about the need for increased bicycle helmet use in Sweden, and to determine what measures can lead to more widespread helmet wearing. The four papers included addressed two main questions: (1) What is the need for increased helmet wearing among different categories of bicyclists in Sweden? (2) Is a non-compulsory local bicycle helmet law a realistic alternative to a mandatory helmet law for all bicyclists? Materials and methods: Observational studies of helmet use by bicyclists in Sweden were conducted once a year (average n = 37,031/year) during the period 1988-2002 (paper I). The general trend in observed helmet wearing in different categories of bicyclists was analyzed by linear regression, and the results were used to predict future trends in helmet wearing. Three studies (papers II-IV) were also performed to evaluate a non-compulsory local bicycle helmet "law" in Motala municipality during the study period 1995 to 1998 (papers II-IV). This law was introduced in 1996 and applies specifically to school children (ages 6-12 years), although the intention is to increase helmet use among all bicyclists. Adoption of the law was accompanied by helmet promotion activities. In one of the studies in the evaluation, written material and in-depth interviews (n=8) were analyzed qualitatively to describe the process and structure of development of the Motala helmet law. The other two studies used a quasi-experimental design to assess the impact of the helmet law: one comprised annual observations of helmet wearing among bicyclists in Motala (average n=2,458/year) and control areas (average n=17,818/year); and the other included questionnaire data on attitudes, beliefs, and self-reported behavior of school children in Motala (n=1,277) and control areas (n=2,198). The average response rate was 72.8%. Results and discussion: There was a significant upward trend in helmet use in all categories of bicyclists from 1988 to 2002. Helmet wearing increased from 20% to 35% among children(≤ 10 years) riding bikes in their leisure time, from 5% to 33% among school children, and from 2% to 14% in adults. Total average helmet use rose from 4% to 17%. However, during the last five years of the study period (1998-2002), there was no upward trend in helmet wearing for any of the categories of bicyclists. If the historic trend in helmet use continues, the average wearing rate will be about 30% by the year 2010. The Motala helmet law was dogged by several problems, mainly during the initiation phase, and some of them led to poor rooting of the law in the schools and indistinct roles and responsibilities of the municipal actors. Despite that, the law initially led to a significant increase in helmet wearing among the primary target group (school children), from a pre-law level of 65% to about 76% six months post-law, whereas thereafter the wearing rate gradually decreased and was at the pre-law level 2 ½ years after the law was adopted. Nonetheless, a weak but significant effect on adult bicyclists remained: the pre-law level of about 2% rose to about 8% at the end of the study period. Only about 10% of bicyclists on bike paths in Motala wore helmets 2 ½ years post-law. The questionnaire study showed one significant effect on school children in Motala two years post-law, namely, a stronger intention to ride bicycles if a national compulsory helmet law was introduced. There was, however, no significant long-term influence on children's attitudes or beliefs about helmet wearing, which agrees with the results of the observational study. General conclusions: It is indeed necessary to increase bicycle helmet wearing in Sweden. Both the current average rate of helmet use and the rate predicted for the near future are far from the goal of 80% that was officially proposed by several years ago. Previous research has shown that, to achieve substantial and sustained bicycle helmet use, it is necessary to use helmet promotion in combination with a national helmet law that is compulsory and applies to all bicyclists. The present evaluation of the non-compulsory local helmet law in Motala indicated that this type of initiative is not a powerful alternative to a mandatory national helmet law. Nevertheless, much has been learned from the initiation and implementation of this local action.

Horse riding is a popular global activity involving a wide range of sporting events including dressage, endurance riding, eventing, show jumping, horse racing and rodeo. Unfortunately, horse riding and equestrian sporting events, report a high prevalence of concussion. The most common mechanism for brain injury in equestrian events involve high levels of linear and rotational acceleration during head impacts when falling from a horse. These accelerations create injurious brain tissue strain. While both linear and rotational accelerations occur during head impacts, the rotational components of acceleration are closely linked to brain tissue strain. To reduce brain strain, helmet technologies have been developed with the aim to reduce head rotational accelerations during an impact. The most common rotational managing technology, multi-directional impact protection system (MIPS), employs a low friction layer to reduce the amount of rotational acceleration sustained by the brain during head impacts. MIPS tests equestrian helmets using a monorail drop rig with a 45-degree steel anvil covered in 80 grit sandpaper at 6.2 m/s. The surface experiencing impact in the MIPS test method is a very low compliant surface (steel). It is impacted at a velocity of 6 m/s, and an anvil angle of 45-degrees. In contrast, most impacts in equestrian involve high compliant material such as sand or turf with an average impact velocity is 9 m/s, and the average angle of impact of 27 degrees. The proposed rotational testing method employed by MIPS may not fully represent the most common accidents involving equestrian events. The objective of this research was to evaluate the effectiveness of a helmet with rotational technology to reduce linear and rotational acceleration, rotational velocity, and maximum principal strain (MPS) in equestrian helmets. An equestrian specific test protocol was developed using the common impact conditions for concussive events for equestrian riders. Nine m/s impact velocity, with an angle of 26.5 degrees to the horizontal axis, and an anvil compliance consisting of 66 mm of 602 vinyl nitrile foam with synthetic grass to represent turf impacts was reported as the most common impact characteristics. Using a Rail Guided Launcher, a helmeted Hybrid III headform was launched and impacted a low and high compliance anvil using the defined velocity and angle parameters. Two equestrian helmet types were impacted, a conventional helmet with no rotational technology and the same helmet model with rotational technology. The impact locations tested included front, side, and rear boss, as these were the most common impact locations reported for concussive events in equestrian. Linear and rotational acceleration and rotational velocity were measured using a DTS SLICE sensor installed inside the headform. The linear and rotational acceleration curves were then used as input to the University College Dublin Brain Trauma Model (V2.0) to calculate MPS. Statistical analysis included four t-tests, two 2x2x3 ANOVA's with 8 pairwise Tukey post-hoc test, significance set to α=0.05. The results were not uniform across impact locations and anvil compliances, the rear boss impact location in helmets with rotational technology revealed significantly lower rotational accelerations and rotational velocity. The results revealed helmets with rotational technology should be designed to perform under these high-energy conditions. If the rotational technology was designed with these considerations, it would be possible to investigate the potential of rotational technologies to decrease dynamic head response and the brain tissue strain.