Protective capacity of ice hockey helmets at different levels of striking compliance

Grau, Santiago de; Post, Andrew; Meehan, Andrew; Champoux, Luc; Hoshizaki, T. Blaine; Gilchrist, Michael D.

doi:10.1007/s12283-020-00325-y

Cited by 11 publications

(20 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Peak vertical forces were, however, lowest for the first impact for 73% of the protectors, indicating that they may have degraded with changes to padding and fatigue of splints. This finding suggests that protectors may need to be replaced after a severe fall onto the hand, even if there is no visible damage, as found for ice hockey helmets 52 and in line with general guidance for helmets. Fatigue of the splints may have also occurred under the quasi-static bend testing of the protectors before impact testing.…”

Section: Discussionsupporting

confidence: 66%

“…To enable the rig to match the loading rate applied to a cadaveric forearm by Greenwald et al, 36 compliant material was added to an aluminum plate (400 mm by 120 mm by 180 mm) that was bolted to the end of the pendulum arm, as done by de Grau et al 52 when testing helmets with a linear impactor. Impacts were conducted with the surrogate hand at maximum extension (∼110° from vertical), so the impactor struck the central core analogous to the wrist.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Impact testing of snowboarding wrist protectors

Adams

Allen

Senior

et al. 2021

Proceedings of the Institution of Mechanical Engineers, Part P:

View full text Add to dashboard Cite

The wrist is a common injury site for snowboarders who often fall onto an outstretched hand. Wrist protectors are worn by some snowboarders to prevent wrist injuries by attenuating impact forces and limiting wrist extension. This paper presents a bespoke pendulum test device for impacting wrist protectors when fitted to a wrist surrogate. The rig can replicate injury risk scenarios, while measuring temporal forces and wrist extension angles. Results from testing 12 snowboarding wrist protectors are presented, including differences in peak vertical force, the time to reach this peak, and energy absorption between products. When compared to an unprotected surrogate, all 12 products lowered the peak force by at least 24% and increased the time to reach this peak by at least 1.8 times. Due to the severity of the load case employed, none of the products lowered the impact force below 2.8 kN, which is the value presented in the literature to fracture a cadaveric wrist. The developed rig could be used to support the development of new wrist protectors, as well as the development of finite element models for predicting wrist protector performance.

show abstract

Section: Discussionsupporting

confidence: 66%

Section: Methodsmentioning

confidence: 99%

Impact testing of snowboarding wrist protectors

Adams

Allen

Senior

et al. 2021

Proceedings of the Institution of Mechanical Engineers, Part P:

View full text Add to dashboard Cite

show abstract

“…The limitations of the video analysis method and impact reconstructions used in the present study have been previously described ( Ghajari et al, 2017 ; Karton et al, 2020 ) and within the supplementary materials , but these methods still remain one of the key approaches to determining the kinematics of the head during sports collisions. We used an unbiased neckform which has been shown to be repeatable and typically gives very small standard deviations on series of impacts to various locations ( Chen et al, 2020 ; de Grau et al, 2020 ; Post et al, 2020 ). The unbiased neck has been shown to perform similarly to the Hybrid-III neck ( Walsh et al, 2018 ).…”

Section: Discussionmentioning

confidence: 99%

Player position in American football influences the magnitude of mechanical strains produced in the location of chronic traumatic encephalopathy pathology: A computational modelling study

Zimmerman

Kim

Karton

et al. 2021

Journal of Biomechanics

View full text Add to dashboard Cite

American football players are frequently exposed to head impacts, which can cause concussions and may lead to neurodegenerative diseases such as chronic traumatic encephalopathy (CTE). Player position appears to influence the risk of concussion but there is limited work on its effect on the risk of CTE. Computational modelling has shown that large brain deformations during head impacts co-localise with CTE pathology in sulci. Here we test whether player position has an effect on brain deformation within the sulci, a possible biomechanical trigger for CTE. We physically reconstructed 148 head impact events from video footage of American Football games. Players were separated into 3 different position profiles based on the magnitude and frequency of impacts. A detailed finite element model of TBI was then used to predict Green-Lagrange strain and strain rate across the brain and in sulci. Using a one-way ANOVA, we found that in positions where players were exposed to large magnitude and low frequency impacts (e.g. defensive back and wide receiver), strain and strain rate across the brain and in sulci were highest. We also found that rotational head motion is a key determinant in producing large strains and strain rates in the sulci. Our results suggest that player position has a significant effect on impact kinematics, influencing the magnitude of deformations within sulci, which spatially corresponds to where CTE pathology is observed. This work can inform future studies investigating different player-position risks for concussion and CTE and guide design of prevention systems.

show abstract

“…shoulder, elbow, or glove-to-head impact) [30,31]. During collisions, the helmet impacts several layers of textiles, protective equipment, and the other player's body, which are typically less stiff than helmet liners [32,33]. Player-toplayer collision head impacts are associated with lower magnitude, but longer duration, head accelerations in comparison to falls onto the ice or against the boards surrounding the ice rink [32,34,35].…”

Section: Motivation For the Researchmentioning

confidence: 99%

“…Due to the requirement to protect well during falls, helmet liners have to be sufficiently stiff. Consequently, compression when impacting a more compliant body is insufficient to efficiently absorb induced energy, leaving players susceptible to concussions [32,33,39]. Designs to protect against a wider range of head impacts, especially player-to-player collisions, such as multilayer foam or shear-thickening polymers, have been introduced with limited success [40][41][42][43].…”

Section: Motivation For the Researchmentioning

confidence: 99%

Towards concussion prevention in ice hockey: mechanical metamaterial liners and helmet assessment

Haid

View full text Add to dashboard Cite

Ice hockey has one of the highest concussion rates in sport. During player-to-player collisions, the most common concussive scenario, helmets have been shown to offer limited protection. Helmet testing that is representative of the broad range of potential head impacts requires extensive specialist equipment, while certification standards are currently not assessing the impact scenario that most commonly causes concussions in ice hockey. Consequently, helmets protect well in the scenario they are certified and designed for – falls onto stiff surfaces – but provide limited protection during other commonly occurring impacts, especially impacts with more compliant bodies. Due to the wide range of injurious head impacts in ice hockey, it is challenging to develop a helmet that protects well in all scenarios. The aim of this programme of research was to develop a simplified test method, capable of replicating common ice hockey head impacts. Then, to investigate the capabilities of a mechanical metamaterial to enhance protection during collisions without compromising protection during more severe head impacts. A novel test method, utilising laboratory equipment that is available to most researchers with an interest in impact protection, to replicate head impacts in ice hockey was developed and validated. It has been shown that a free-fall drop test method, with interchangeable impact surface orientation and compliance, can be used to create impact events that are representative of a range of common ice hockey head impacts. This newly developed test method can produce kinematic responses within less than 10% of key metrics obtained by current best practice methods to replicate ice hockey collisions and may facilitate widespread and more thorough testing in academic research and modifications to current test standard procedures. A series of investigations were conducted to assess the potential of a mechanical metamaterial, comprising bi-beam structures, with an adaptive response to specific impact scenarios. Testing and modelling of individual bi-beams, unit cells, and cellular structures of bi-beams suggest a cellular structure, comprising bi-beams, can be developed by arranging unit cells relative to each other between two stiff sandwich plates. It has been shown that controlling the direction of buckling and the associated contact situations, can cause an abrupt switch in stiffness (~155 – 180%) in axial direction. Applied as a liner in an ice hockey helmet, this could achieve enhanced protection against an additional cause of injury – collisions – without compromising the performance in the scenario the helmets are currently designed for – falls. Dimensional scalability facilitates a wide range of possible designs and fields of application. This programme of research contributes to the body of knowledge of head impact testing and helmet technologies to better protect players. Findings could help in developing better helmets that protect players against a wider range of head impacts which in turn would reduce concussions and make participation safer.

show abstract

Protective capacity of ice hockey helmets at different levels of striking compliance

Cited by 11 publications

References 35 publications

Impact testing of snowboarding wrist protectors

Impact testing of snowboarding wrist protectors

Player position in American football influences the magnitude of mechanical strains produced in the location of chronic traumatic encephalopathy pathology: A computational modelling study

Towards concussion prevention in ice hockey: mechanical metamaterial liners and helmet assessment

Contact Info

Product

Resources

About