Skiing: People who ski report high numbers of concussions, according to the study, though part of that is due to the large number of skiers. Skiers also face an especially high risk for ACL tears and other knee injuries.
Source: Sharma et al., Orthopaedic Journal of Sports Medicine, January 2015; Kim et al., American Journal of Sports Medicine, January 20, 2012
Snowboarding: Snowboarders face the highest concussion risk of the athletes in the study, with a risk per-hour spent riding that's triple that of skiers.
Source: Sharma et al.
Snowmobiling: Snowmobilers didn't have particularly high injury rates in this study, though risks of skull fractures were higher than for other winter sports. Other studies have shown risks for serious injury and death, often related to snowmobiling after drinking.
Source: Sharma et al., Hoey, Canadian Medical Association Journal, March 2003
Motocross: There wasn't enough data to calculate injury rates per-hour spent in the sport, but motocross riders had the highest incidence of broken necks; 27.6% of all reported neck fractures in the study came from motocross.
Source: Sharma et al.
Skateboarding: By far, skateboarders were the most likely to suffer a skull fracture. They also had the highest overall risk for head and neck injuries.
Source: Sharma et al.
Surfing: Surfers had one of the lowest concussion rates in the study, but had especially high rates of neck fractures — 38 times higher than skateboarders.
Source: Sharma et al.
