Hockey head impact research highlights need to improve injury prevention

Simon Fraser University researchers are learning more about how the scenarios for head impacts in hockey—from player clashes to contact with the boards or glass—affect impact severity. Their findings, reported in the journal Scientific Reports, should help to inform improvements in injury prevention.

In a follow-up to their previous study on how hockey head impacts occur, researchers returned to a Burnaby rink to follow 43 university men’s hockey players over another three seasons (2016-2019).

This time they compared video evidence—gleaned from cameras strategically placed around the rink to capture head impacts during play—with data from helmet-mounted sensors, or GForceTrackers, which measured head linear accelerations and rotational velocities. In all, 234 head impact incidents were recorded.

The head impact videos were analyzed with a validated questionnaire that probed situational factors before, during, and after impact to the head. Videos were then paired with corresponding helmet sensor data.

“We found that players with visible signs of concussion—such as clutching the head or slow to get up after the impact—experienced greater head rotational velocities than those without signs,” says Olivia Aguiar, a PhD student in SFU’s Department of Biomedical Physiology and Kinesiology (BPK). “Regardless of whether a hit to the head appears to be big or small, any athlete with visible signs of concussion must be removed from play and assessed by a medical professional.”

Researchers also found that while shoulder-to-head impacts occurred more frequently than hand or elbow contact, glass-to-head impacts were nearly four times more common—and just as severe—as board-to-head impacts. 

And while the most severe head impacts resulted in penalties, researchers say rules that focus on “primary targeting of the head” offer a limited solution. “The head was the initial site of contact in 24 per cent of cases, of which only four per cent were penalized,” says Aguiar. “More often we saw some degree of player contact prior to the head being struck and found that these head impacts were just as severe. We suggest that prevention strategies aim to reduce any contact to the head, not just instances where the head is targeted.” 

Despite growing evidence of repeated sub-concussive impacts, which are more prevalent than concussions in hockey and associated with structural changes to the brain, including symptoms of depression and cognitive impairment, the researchers say a lack of understanding on the most common and severe types of head impacts prevails.

“This is a barrier to the design and development of strategies for better protecting the brain, such as rule changes, skills training, and improvements to protective equipment as well as rink design,” says Aguiar.

“We’re hopeful that adding to the evidence on head impacts in hockey will lead to better ways to create a safer game and preserve brain health.”