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Helmets need to be developed using injury data and suitable standards
Haid was the first to raise the issue of helmet use in skiing when, in 1955, he published a study of fatal ski injuries treated in Innsbruck in Austria and suggested that head injury might be less severe if a helmet was worn.1 Since then the main proponent of helmet use in all aspects of skiing has been the Swiss neurosurgeon, Sooyoung Oh, although the evidence presented for his recommendations is anecdotal.2,3
The issue of sport specific helmet design becomes more important. Because at the present point in time we have only limited data on precise injury mechanisms in skiing and snowboarding, which suggests that there is no common mechanism to the occurrence of concussive injuries or skull fractures in these sports.4,5 This would mean that any helmet would have to be designed differently for these two sports. Injuries occurring in ski racing occur at far higher impact velocities than recreational skiing and furthermore usually occur on ice rather than snow. Once again, any potential helmet would have to be designed with these factors in mind. The ability of a conventional ski helmet to protect the brain from the velocities achieved in elite World Cup downhill racing is unachievable at present. Attention to other safety factors such as slope maintenance, flexible race gates, and crash barriers at races therefore becomes a more effective safety factor than helmet use.
Without valid helmet material and manufacturing standards, there is no guarantee that an off the shelf helmet has any protective capacity whatsoever. Furthermore depending on the nature and quality of the materials used, there is a potential for increasing cerebral injury rate significantly. The only international standard applicable for skiing helmets is the British standard BS EN 1077-1996, which sets out minimum standards requirements and helmets testing protocols for alpine skiers (including children) in competitions.
Issues about helmet maintenance and fit become important as well. This is especially true in children who may potentially be a group with the most to gain by wearing a suitable protective helmet. If the helmet does not fit firmly, then the protective capability is reduced. If the helmet is oversized and loose, as many parents may purchase a helmet with “room to grow” for their child, the chances of this being effective are small and potential problems in reducing vision and hearing may increase collision rates which is already the major injury mechanism in the paediatric age group.
Because of cost, helmets are usually made in two or three shell sizes with variations in liner thickness to accommodate a range of head sizes in each shell size. This means that the largest size in each shell is critical since its liner is the thinnest. The requirements of a size 8 helmet which must decelerate a 6.0 kg head are different to a size 6 3/4 helmet which must protect a 4.2 kg head. The outer shell size remains the same in both cases but the liner thickness is the critical factor. Simple changes such as shifting head sizes into a larger shell may therefore protect greater numbers of participants. The problem is all too obvious in skiing where participants vary from small children through to adults and any proposed helmet must cope with this basic fact.
The possibility of a large helmet having a guillotining effect on the cervical spine needs to be explored. Until appropriate design standards exist, this risk must be viewed with some caution. There is evidence from the literature that children have a higher rate of neck and back injuries and the effect of helmets in contributing to this problem has not been adequately excluded.4,5
If a suitable helmet was available, then who would benefit? The highest risk groups would be ski racers, ski jumpers, freestyle aerialists, and children in all categories of skiing. The evidence that adult recreational skiers would benefit by helmets is not proven. Fortunately catastrophic ski injury, although tragic, is rare.5–,7 The risk of injury is reducing at all ski resorts over time and this may have more to do with slope maintenance and grooming, improved ski equipment, improved skill development through ski school instruction, skier fitness, and education. There is probably still much to do in terms of slope control—for example, restricting or removing ski passes from skiers who violate the skiers responsibility code by skiing too fast, out of control, or dangerously placing themselves as well as other slope users at risk.
At the present time no suitable helmet exists which is likely to protect all skiers and snowboarders. Although theoretically attractive in reducing head injury rates, the idea of skiers obtaining inferior and potentially dangerous helmets should not be encouraged. Better injury data analysis and suitable helmet standards are required to initiate the process of developing an appropriate protective helmet. Significant head injuries are rare in skiing and snowboarding and even if all participants wore helmets, it would not eliminate fatal injuries and may potentially increase the rate of other neurological injuries.