August 20, 2020

Watching hockey in the name of science might sound too good to be true, but that’s exactly what a team of SFU researchers did for a five-year study on hockey head impacts, recently published as an award-winning paper in the Journal of Biomechanics.

The researchers documented and analysed head impacts that occurred during men’s university ice hockey games, providing valuable data to better understand head injuries and improve player safety.

Led by SFU PhD student Olivia Aguiar, a team of colleagues from SFU’s Injury Prevention and Mobility Lab attended 33 SFU men’s hockey team games between 2014-19.

During the games, researchers were spread out around the arena and used five strategically-placed cameras to capture any head impacts that occurred during play.

In total, they collected video footage of 449 head impacts experienced by 37 players. Each impact was carefully analysed for its contributing factors such as ice location, puck possession, gaze direction, what object struck the head, location of head impact, trajectory of colliding players, and even what penalties occurred as a result of the impact.

While the majority of events resulting in head impacts involved contact with another player (93 per cent), the head was just as likely to be struck by an environmental object (most often the glass), as by a body part of an opposing player (most often the hand). Head impacts most often occurred along the boards to players who did not have puck possession. Glass-to-head impacts represented 30 per cent of all cases, four times as common as board-to-head impacts. Hand-to-head impacts were twice as common as shoulder or elbow-to-head impacts.

“Previous studies have identified player-to-player impacts as a major cause of brain injuries but we have shown that impacts with environmental objects, particularly the glass, are just as prevalent,” says Aguiar. “This is significant since a lot of attention goes into how to keep players safe when colliding with each other, with less thought being given to environmental modifications.” 

The study also found that in more than a quarter of all recorded events, there were two or more successive impacts to the head – a finding Aguiar found concerning, especially given the damage that even small repeated blows to the head can cause. 

“I think there is a misconception that in order to sustain brain damage you need to have a very severe head impact. However, studies have shown that repetitive blows to the head, like we often see in hockey, can lead to neurological consequences weeks, months or even years down the road.”

According to Aguiar, the smaller blows to the head are hard to avoid in contact sports like hockey – an issue that was further illustrated by their finding that just 16 per cent of head impacts with another player resulted in infractions. 

The study suggests further research is needed to determine how stricter rule enforcement and modifications to surroundings and equipment, such as rink glass and glove pads, might play a role in reducing the frequency and severity of head impacts in ice hockey.

Aguiar is continuing with her research and currently completing a follow-up study that includes additional data derived from impact sensors placed in the helmets of hockey players.