To examine if head impact kinematics (HIK) predict in-season concussion or acute lower extremity injury (LEI) in collegiate ice hockey

Sustaining head impacts in sport regularly may be damaging to long-term neurological health. Individuals who sustain higher head impact loads may be at increased risk for concussion, and furthermore, individuals who sustain a concussion are more likely to sustain a subsequent LEI than those without a history of concussion.

Twenty-nine collegiate club male ice hockey players (age: 20.2±1.4) over the 2015-2018 seasons completed a survey at the conclusion of their season of LEI and concussion in-season. HIK (number of impacts, and mean, peak, and cumulative linear acceleration) were recorded via tri-axial accelerometers (Triax, Nowalk, CT) that each player wore for games/practices with a 10g impact threshold. Two binary logistic regressions were performed to determine if either sustaining a concussion or LEI was predicted by HIK.

There was no relationship between LEI or concussion with number of impacts (β:-0.018, p=0.711, 95% CI:-0.12-0.84; β:-0.039, p=0.55, 95% CI: -0.21-0.08, respectively), or mean (β:0.041, p=0.79, 95% CI: -0.26-0.38; β:-0.040, p=0.81, 95% CI: -0.37-0.32), peak (β:-0.065, p=0.14, 95%CI: -0.16-0.01; β:0.0007, p=0.99, 95% CI: -0.09-0.09), or cumulative acceleration (β:0.001, p=0.42, 95% CI: -0.001-0.004; β:0.001, p=0.55, 95% CI:-0.002-0.005). 7/29 players sustained a LEI and 6/29 sustained a concussion. Mean value for number of impacts was 59.7±49.1 (range:3-171); mean acceleration: 33.9±5.3g (range:22.0-42.22), peak: 71.8±19.0g (range: 30.8-108.4); cumulative: 2,108.5±1,793.8g (range 71.8-6517.2).

The main finding of this study is that greater HIK do not predict whether individuals sustained either an acute LEI or concussion during the season, albeit from a small sample. As HIK load is related to concussion incidence, it is possible HIK load may also be related to LEI, however, these results suggest HIK alone is not related to either in an ice hockey cohort.