The Ice Hockey Summit III has published a list of action items to address the diagnosis, clinical care and prevention of sports-related concussion (Smith et al. Curr Sports Med Rep 2019;18:23-34). The report follows on guidelines on mild traumatic brain injury in children by the U.S. Centers for Disease Control (Lumba-Brown et al. JAMA Pediatr 2018;172:e182853), and guidelines on the management of concussion by the American Academy of Neurology (Giza et al. Neurology 2013;80:2250-7).
According to the Summit, Canada has the largest number of ice hockey players in the world, both as an absolute number (estimated at 631,295) and as a proportion of its population (1.8% compared to 0.17% of the U.S. population). The incidence of concussion is estimated at 1.47-1.58 per 1000 players for children, 0.54/1000 for high school, and 0.5-15.8/1000 for Junior A and the National Hockey League (NHL). Concussions represent about 20-26% of all hockey-related injuries. The causes of concussion differ by sex among elite players. For women, the causes are falls (63%) and collisions (37%); for men, the causes are collisions (80%), fights (8%) and falls (7%).
Efforts to reduce the risk of concussion in hockey have included elimination of body checking, which reduced the number of concussions by 67% when introduced at the Peewee level (ages 11-12). Fair Play rules, begun in Quebec in 1979, have also reduced concussion rates at tournaments. Interestingly, after the NHL introduced a zero-tolerance rule for head contact, there was no reduction in the concussion rate.
The report notes that concussion is ideally diagnosed at rink side so that players can be removed from the game if findings are consistent with concussion. Of relevance are the observed mechanism of injury, abnormal physical exam, neurological signs/symptoms, and testing of cognition, balance and oculomotor function. Recommended tests are the Sideline Assessment of Concussion Test (SCAT5) to evaluate symptoms, cognition and balance, and the King-Devick Test (KDT) of cognition. In a medical setting, diagnosis is based on an evaluation of the timing and mechanism of head impact, risk factors, prior history of concussion, signs/symptoms such as loss of consciousness and amnesia, and duration of symptoms. Tests include the Symptom Severity Score (a 6-point change from baseline is meaningful); SCAT5 or the Montreal Cognitive Assessment (MOCA) for cognition; computerized neurophysiologic assessments; dynamic balance and vestibular function; and vestibulo-ocular reflex. Devices to assess balance approved by the FDA include the Sway balance and King-Devick balance test app. CT imaging is the preferred modality to detect hemorrhagic intracranial lesions and skull/facial fractures, however, CT will not detect diffuse axonal injury.
Key action items recommended at the Summit are to:
- Create a national concussion database
- Study the value of equipment modifications
- Eliminate body checking at the Bantam level, expand Fair Play rules to all levels of youth hockey and impose a game-ejection penalty for fighting
- Promote neck strengthening and dynamic stabilization into hockey training
- Focus research efforts on pharmacological management of concussion and its sequelae.