Tuesday December 4 2007
Wearing a helmet could prevent injury
“Acrobatics on snow lead to rise in deaths and injuries” said a headline in The Times today. The newspaper, along with the Daily Mail and Channel 4 News, reported that while general winter sport-related injuries have declined in recent years, the number of head injuries and fatalities among skiers and snowboarders are on the increase, and that young male snowboarders are particularly at risk.
The stories are based on a comprehensive systematic review of the literature about head injuries in skiing and snowboarding. The review notes that the actual risk of having a head injury is relatively small but says this should not stop people taking precautions, such as wearing a helmet, particularly if involved in high speed or acrobatic activities.
Where did the story come from?
Drs Charles Tator, Alun Ackery and colleagues from the Universities of Toronto and Calgary, and ThinkFirst Canada carried out this research. The funding sources for this study were not clear, but the authors said they had no competing interests to declare. It was published in the peer-reviewed medical journal Injury Prevention.
What kind of scientific study was this?
This was a systematic review looking at how often people suffered traumatic brain injuries (TBI) and spinal cord injuries (SCI) while skiing and snowboarding, and whether prevention strategies worked. The researchers looked at several computer databases and search engines to identify all articles and conference abstracts about injuries to the brain or spinal cord while skiing or snowboarding published between 1990 and 2004. They selected the studies that had recorded how common TBI or SCI were in skiing and snowboarding. Researchers included case-control, cohort and cross-sectional studies, and these could be either prospective or retrospective.
They included studies based on trauma registries and databases, as well as death certificates and coroners’ reports. Other reviews providing independent analyses were also included, as were studies not in the English language. Any severity of TBI was included, as the authors acknowledged that the definition of “head injury” has changed over the past 10 years. Articles reporting single cases of TBI or SCI were excluded, as were studies which did not provide comprehensive information.
What were the results of the study?
The researchers identified 24 articles for inclusion, which gave estimates of the frequency of TBI and SCI associated with skiing and snowboarding in 10 countries. The overall risk of injury while skiing or snowboarding was relatively low, with one review reporting that the incidence of all injuries (not just TBI and SCI) dropped from 5–8 injuries per 1,000 skiing days in the 1970s to 2–3 injuries per 1,000 skiing days currently. The studies suggested that snowboarders were more likely to sustain injuries than skiers. One review estimated that head injuries accounted for about 3–15%, and SCI for between 1–13% of all injuries in skiers and snowboarders.
The studies suggested that both TBI and SCI were becoming more common. Fatalities while skiing were estimated to be about 0.5–2 cases per million skier visits, and traumatic brain injury was the main cause of death among skiers and snowboarders. One study found that younger skiers and snowboarders and male skiers and snowboarders were more likely to sustain head injuries than older or female skiers and snowboarders. One study in Canada found that jumps were the cause of SCI in about three quarters of cases in snowboarders, with the majority of other cases caused by falls. However, in skiers, falls were the main cause of SCI, followed by jumps. Although case series suggested that people with head injuries tended not to have been wearing helmets, only three case-control studies specifically looked at whether helmets protected against head injuries. These studies suggested that helmets could reduce head injuries by between 22% and 60%.
What interpretations did the researchers draw from these results?
The researchers concluded that rates of traumatic brain injury and spinal cord injuries occurring during skiing and snowboarding are increasing, and that this has paralleled the increase in high speed and acrobatic activities. They say that more should be done to promote measures that prevent head injuries while skiing and snowboarding, including the wearing of helmets, and they “strongly recommend the use of helmets by all skiing and snowboard participants”.
What does the NHS Knowledge Service make of this study?
This was a comprehensive review of the literature about head injuries in skiing and snowboarding, which does indicate that these injuries may be increasing, and that the risk of these injuries may be reduced by wearing helmets. As the authors acknowledge, the definition of head injury has changed over time, and this may mean that estimates of the rate of head injury from studies conducted in different time periods may not be directly comparable. However, it is important to note that the actual risk of having a head injury is relatively small, but this should not stop people taking sensible precautions, particularly if they are involved in high speed or acrobatic activity.
Sir Muir Gray adds...
The evidence looks good enough for action; stay clear of young males seems to be sensible health advice.