Now showing 1 - 2 of 2
  • Publication
    For ASTM F-08: Protective Capacity of Ice Hockey Player Helmets against Puck Impacts
    Many studies have assessed the ability of hockey helmets to protect against falls and collisions, yet none have addressed the injury risk associated with puck impacts. Thus, the purpose of this study was to document the capacity of a typical vinyl nitrile ice hockey helmet to reduce head accelerations and brain deformation caused by a puck impact. A bare and a helmeted Hybrid III male 50th percentile headform was struck with a puck three times to the forehead at 17, 23, 29, 35, and 41 m/s using a pneumatic puck launcher. Linear and rotational accelerations were captured using accelerometers fitted in the headform and used as input in the University College Dublin Brain Trauma Model to obtain brain deformation. The helmet reduced peak resultant linear acceleration, peak resultant rotational acceleration, and maximum principal strain, but a comparison with published brain injury risk curves shows that it did not reduce the concussion risk below 50 % for impacts at or above 23 m/s. Thus, a vinyl nitrile ice hockey helmet can protect players from direct puck impacts in amateur and youth leagues but may not be adequate in competitive elite leagues, where the puck can be shot at velocities well above 23 m/s. Furthermore, competitive adult male ice hockey players struck to the helmet by a puck may need to consider changing their helmet, as it was shown that direct impacts at or above 35 m/s decreased the helmet’s ability to reduce head peak linear acceleration in subsequent impacts.
    Scopus© Citations 8  444
  • Publication
    Estimating the influence of neckform compliance on brain tissue strain during a Helmeted impact
    (Society of Automotive Engineers, 2010-11) ; ;
    The aim of this study was to determine if a change in neckform compliance could influence maximum principal strain in the brain white and grey matter, the brain stem and the cerebellum. This was done by impacting a Hybrid III headform with a 16.6 kg impactor arm at 5 m/s. Three different Hybrid III neckforms were used: 1) one 50th percentile male neckform - standard neckform; 2) one 50th percentile male neckform plus 30 per cent compliance - soft neckform; 3) one 50th percentile male neckform minus 30 per cent compliance - stiff neckform. The kinematic data obtained was then used to drive a finite element model developed by University College Dublin. The results showed that a decrease in neckform compliance had a significant effect on maximal principal strain in the cerebellum, where the stiff neck (0.050 ± 0.004) generated higher maximum principal strains than the standard neck (0.036 ± 0.003) and the soft neck (0.037 ± 0.001). There were no significant differences between the stiff (0.122 ± 0.013), standard (0.114 ± 0.020) and soft neck (0.119 ± 0.019) in the white matter; the stiff (0.168 ± 0.011), standard (0.176 ± 0.011) and soft neck (0.176 ± 0.007) in the grey matter; or the stiff (0.080 ± 0.003), standard (0.081 ± 0.006) and soft neck (0.085 ± 0.009) in the brain stem. The results were not linked to brain injury due to the absence of a commonly accepted threshold.
      417