Concussions, or mild traumatic brain injuries (mTBI), occur due to an impact on the head and are the most common type of brain injury for goaltenders in the sport of ice hockey. The two main techniques used to mitigate concussion risk for ice hockey goaltenders include improving the impact absorption capabilities of the goaltender helmets and increasing the athlete’s cervical muscle strength. Based on these two strategies, this study examined the effect of thermoplastic polyurethane (TPU) as a goaltender helmet liner material to mitigate concussion risk for individuals with different neck strength levels during simulated horizontal head collisions.

To address the purpose of this study, static testing was conducted to examine the material properties of the goaltender helmet liners, which was then used to identify the best TPU liner design that improved the performance of the goaltender helmet technology. One particular TPU liner design was found to weigh 2.7 times more on average than the standard liner;​ however, it was capable of statically absorbing 10.8 times more energy per kilogram than the standard liner. The researcher selected this TPU design and used it in repeated impact testing to further gauge the performance of the TPU and standard liner materials compared to a bare head without liner protection. Repeated dynamic impact trials revealed that the TPU liner mitigated impacts similarly to the standard liner, providing evidence of the TPU effectiveness as a possible helmet liner.

The researcher then conducted dynamic testing to simulate goaltenders’ head collisions with different neck strength levels to assess the protective capabilities of the goaltender helmet technology during horizontal head collisions. A pneumatic impactor instrumented with a surrogate headform and mechanical neckform was used to simulate the horizontal head collisions. The dynamic data collection included 18 impact velocities across three helmet locations (front, side, and back), four neck strength levels (30th percentile female, 50th percentile female, 50th percentile male, and 80th percentile male), and two helmet conditions (helmet fitted with TPU and standard helmet) for measures of liner acceleration and risk of injury.

The results of the dynamically simulated goaltenders’ head collisions indicated that the TPU liner resulted in lower peak resultant linear acceleration (PRLA) values than the standard liner for the 80th percentile male neck strength level. Similarly, the TPU liner resulted in lower risk of head injury (HIC) scores for the 80th percentile male neck strength level. The results, however, revealed no statistically significant effect on neck strength levels for measures of PRLA and HIC for any of the helmet impact locations tested. Although the TPU liner performed better than the standard liner during static and repeated impact testing, the simulated goaltenders’ head collision suggested further research is required into the design of the TPU liner to improve its capability to mitigate the risk of head injury across different neck strength levels and helmet locations.