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Introduction: The Norwegian Ski Lift Association has since 1996 conducted a central registration of the injuries occurring in the major Norwegian ski resorts to survey the injury types. The aim of this study was to report injury trends in the period 1996–2012.

Material and methods: The injuries occurring in 7–16 Norwegian ski resorts were recorded by ski patrols during the 16 winter seasons 1996/1997–2011/2012 and related to a series of demographic factors. The number of skiing/boarder days was calculated from sold lift tickets (day cards), but these were only centrally recorded from the 2000/2001 season.

Results: A total of 55127 injured skiers and boarders were recorded. The injury rate dropped from 1.47 to 1.27 injuries per 1000 skier/boarder days ( < 0.001), and the skiing/boarding ability increased ( < 0.001) in the period 2000–2012. Most of the injuries occurred on groomed slopes, but an increasing number of injuries occurred in terrain parks, from only 4% in the 2000/2002 seasons to 24% in the last two seasons. More serious injuries (fractures and back injuries) were recorded in terrain parks than those occurring at other locations. Many of the injuries were similarly distributed among skiers and boarders, but alpine skiers suffered more lower extremity injuries, especially knee injuries (24%) compared to snowboarders (7%), whereas the reverse was observed for wrist injuries with 22% for snowboarders and 5% for alpine skiers in the last 2-year period ( < 0.001). The prevalence of knee injuries among alpine skiers has been about 25% in the period 1996–2012, but wrist injuries among snowboarders dropped from 29 to 22% ( < 0.001). The prevalence of knee injuries was twice as high for females (31%) as for males (15%), whereas the reverse was observed for shoulder injuries with 19% for males and 7% for females in the last 2-year period ( < 0.001). These differences have been observed during the whole period. Lower leg fracture for alpine skiers <13 years dropped from 20 to 13% in the period ( < 0.001), but has remained unchanged with about 4% for teenagers and adult skiers. Helmet use by injured skiers/boarders has increased from 11 to 81% in the period, and the prevalence of head injuries has dropped from 19 to 16% ( < 0.001).

Conclusion: The injury rate on Norwegian slopes dropped with 14% in the period 2000–2012. The prevalence of back injuries for injured snowboarders increased by 100% from 1996 to 2012, and this may be related to one-third of the injuries occurred in terrain parks at the end of the period. The prevalence of lower leg fracture in alpine children is declined by 35% in the period. Use of helmet by injured skiers/boarders increased from 11 to 81% and the prevalence of head injuries dropped with 16% during the same period.

Ski patrol national incident data were analysed in New Zealand for alpine skiing and snowboarding injuries from 4 June 2010 to 9 November 2014. Over five winter seasons, there were 5,861,643 visitations and 18,382 incidents. The injury rate per 1000 skier/boarder days was relatively constant (3.2, 3.3, 3.4, 2.7, and 3.1, respectively). Falls accounted for the injury mechanism in 74.3% of all injuries. Four died after catastrophic falls (two skiing, two snowboarding). Overall, more knee injuries occurred skiing in soft snow conditions than hard (55 vs. 45%). Advanced skiers were 2.2 times more likely to sustain a knee injury with non-release of the ski-binding in hard snow surface conditions than when the ski-binding released. Despite increased helmet usage (42–83%), there was a very likely increase in concussion (1.29, 99% CI 1.06–1.57). Hard snow conditions increased wrist injuries for both intermediate and novice snowboarders (30 and 12%, respectively). Wrist protection was most likely to be beneficial in preventing wrist injuries (hazard ratio 0.65, 99% CI O.54–0.79). Good visibility compared to poor visibility led to a twofold increase in injuries. Increased slope congestion, changes in direction to avoid collision with others and speed were possible contributing factors. Collisions accounted for 9.6% of all injuries. Going forward New Zealand injury prevention initiatives need to be multifaceted. Recreational skiers need to ski on torque-tested equipment with release settings that are a match for current physical parameters, style, and the ability to ski in different snow surface conditions. Further research is needed to determine whether wearing a helmet increases reckless behaviour in some age groups. An international standard for snow sports wrist protectors with proven dimensions is also needed before ski areas can make any further investment in wrist protectors.

Introduction: Skiing and snowboarding are two of the most popular sports in Switzerland, but their popularity means that the absolute number of injuries remains high. To plan and evaluate effective injury prevention, detailed insights into the injuries that occur are needed. Objective: The aim of this study was to characterize the current status (average winter season 2008–2012) and trends in injury rate (between 2005 and 2012) and fatality rate (between 2000 and 2014) among skiers and snowboarders in Switzerland. Materials/Methods: Injury data from different sources were collected and analyzed. Extrapolation and estimates were made based on a special household survey and insurance data. All fatal injuries were recorded in a separate database. Moreover, an annual survey on Swiss slopes was conducted that delivered different information about skiers and snowboarders in these areas. Skier days were collected by the Swiss Cableways. Results: The rate of sustaining an injury while skiing or snowboarding on Swiss slopes was 2.8 per 1000 skier days on average from 2008 to 2010. The fatality rate was 0.7 deaths per one million skier days in the same period of time. The injury rate remained relatively stable between 2005 and 2012, and the fatality rate has not changed since 2000. Discussion: Compared with other countries, the rates of injury or even fatality while skiing or snowboarding falls in the mid-range for Switzerland; however, further prevention efforts targeting behavior and conditions are needed to minimize and even reduce injuries.

To accurately inform injury-prevention initiatives an in-depth evaluation of the utility of injury-incidence databases is essential. As part of development of a 5-year national injury-prevention strategy for snow sports in New Zealand, injury rates were compared in two databases: the Accident Compensation Commission (ACC) claims database of all snow-sports injuries treated by physiotherapists or doctors and the national incident database (NID) of injuries treated at all commercial ski areas. The ACC database focuses on treatment costs, whereas the NID database provides details of skier/boarder ability, terrain, surface condition, visibility, and equipment factors, all important information for developing injury-prevention interventions. The total injury rate in the ACC database was 8.8 injuries per 1000 skier/boarder days in the 2010 and 2011 winter seasons. The NID revealed that only one-third of these injuries were assessed and treated at mountain clinics. Sprains accounted for the greatest difference in injury rates between the ACC and the NID (5.3 and 1.3, respectively). Rates of all other main types of injury where higher in the ACC. This “bypass” effect likely represents a delay in seeking treatment that may be explained by increased swelling or pain after leaving the ski area. The bypass effect presumably applies to injury rates in all studies based solely on mountain-clinic incident data and needs to be taken into account when assessing injury trends and aetiology in alpine skiing and snowboarding.

Background: Currently, there are no recommended assessment protocols for monitoring possible effects of head injury in snowsports athletes who are in competition and training. Objective: This project evaluated the Sport Concussion Assessment Tool 2 (SCAT2) for concussion assessment in a snowsport athlete group. In addition, the project determined the effectiveness of enhancing the SCAT2 protocol by using accelerometer smartphone technology in the balance assessment component of the test battery, with a view to an enhanced protocol for assessment of changes in human motor performance post-concussion injury. Methods: The research team recruited 22 athletes from the New South Wales Institute of Sport and the Olympic Winter Institute Australia snowsport athlete squads who were undertaking baseline sport science testing during the Australian 2012 and 2013 winter seasons. Results: Overall correlation between the SCAT 2 over two separate occasions was moderate/strong (Pearson’s = 0.58, = 0.006). Examination of the subcategories within the SCAT2 indicated that the overall correlation was being mediated by the strong correlation of the subset “Symptom Score.” The subset “Balance Score” did not correlate across test occasions ( = 0.42, = 0.054). There were no other significant correlations across the two occasions of testing. Those who had reported a major head impact history, signified by damage to their helmet during the impact, were significantly older (21.5, SD 4.6 years) than the group not reporting a major head impact (17.5, SD 2.6 years). Two of the instrumented balance test measures, one in the double-leg stance and one in the single-leg stance protocol, showed a significant difference between the “major helmet impact” and “no helmet impact” groups warranting further investigation in a larger sample.

Alpine touring (AT) is a subdiscipline of alpine skiing where skiers ascend and descend snow slopes under their own power. Specialized equipment has been developed for AT skiing, including Tech/Pin bindings that rely on metal inserts molded into AT boots to rigidly couple the boot to the binding. The current lack of standardization has resulted in significant variation in tech insert geometry between boot manufacturers. It is hypothesized that the constraint forces from the tech binding on AT boots are highly sensitive to variations in tech insert geometry.

The dimensions of tech inserts in toe region of AT boots were measured from five manufacturers’ boots. The constraint force applied by the toe pieces throughout their travel was measured quasi-statically using custom-built fixture on ten models of tech bindings from five manufacturers. In addition, the retention and release characteristics for an applied twisting torque were measured for the AT boots in the Tech/Pin binding toe pieces using an ASTM F504 test apparatus. Linear statistical models were developed to predict the measured retention-release behavior using the clamping force and tech insert geometry as predictor variables. The relative importance of each predictor variable from the linear model was then calculated.

The compressive forces applied to the AT boots were significantly different between bindings for the same boot, but not significantly different for the AT boots in any particular binding ( < 0.001). Across all AT boots tested, the twisting release torque was not significantly different between bindings for a given boot ( = 0.81); however, significant differences in release torque were found between boots in any particular binding ( < 0.001). Boot dimensions at the toe had the largest influence on release torque (~85%) while the compressive force had the smallest influence (~15%).

Tech/Pin binding toe pieces are sensitive to small changes in tech insert geometry. This study only examined toe-piece kinematics and forces of tech bindings. Based on the data presented, a companion study will test Tech/Pin boot-binding systems with both the toe and heelpieces.

Alpine touring (AT) is a subdiscipline of alpine skiing where skiers ascend and descend snow slopes under their own power. Specialized equipment has been developed for AT skiing, including Tech/Pin bindings that rely on metal inserts molded into AT boots to rigidly couple the boot to the binding. The current lack of standardization has resulted in significant variation in tech insert geometry between boot manufacturers. A companion study examined the effects of inter-manufacturer variation of boots and bindings on the release characteristics of the toe piece of Tech/Pin bindings. This study continues this work and examines how inter-manufacturer variability affects the Tech/Pin boot-binding system as a whole, when both the toe and heelpiece are engaged.

The retention and release characteristics for an applied twisting torque were measured for the AT boots in the Tech/Pin binding toe pieces using an ASTM F504 test apparatus. Linear statistical models were developed to predict the measured retention-release behavior using the clamping force and tech insert geometry as predictor variables. The relative importance of each predictor variable from the linear model was then calculated.

Tech/Pin boot-binding systems have variations in release torque that exceed the minimum-maximum allowable release envelope prescribed by international standards. These variations stem from using boots from different manufacturers in a given binding. The indicator settings in these bindings do not change the release torque at the same proportional rate as other AT and alpine ski equipment. Skiers should not assume that Tech/Pin bindings will provide the same retention-release characteristics as alpine ski equipment, nor that the numerical indicator settings on Tech/Pin bindings are equivalent to alpine bindings. Homogenizing boot geometry would reduce the amount of variation in release torque from these boot-binding systems, but would not eliminate the problem completely, and could exacerbate the problems for users on one far end of the binding setting scale or the other.

Background: Alpine skiing is a popular winter sport that is confronted with high injury rates. Ski bindings are often mounted on ski plates, which can positively affect the release consistency of ski bindings and thus improve skiing safety. The aim of the study was to explore, if a new ski plate design of which the middle main part was “floating” on rocker arms improved the release consistency of ski bindings when the ski was deflected.

Method: In order to test the new ski plate, three pairs of equal slalom skis were equipped with identical ski bindings. They were mounted: (1) directly to the ski, (2) on the original ski plate, and (3) on the new ski plate. The forward bending release and the torsion release behaviour of these three ski-plate-binding set-ups were tested on a standardized testing device under three conditions: a flat ski, ski-deflection according to the ISO-standard and an extreme ski-deflection.

Results: One-way ANOVA with Tukey post hoc test revealed that all comparisons among different mountings of the binding under three conditions, except in three occurrences when comparing no plate versus new plate, were significantly different. In addition, the new ski plate demonstrated a more consistent torsion release behaviour with almost no shift in the release load (~ −1.5%) for both tested ski-deflections. The majority of relative differences ranged between 6.9 and 8.2% between the three tested mounting conditions with respect to the forward release.

Conclusion: Mounting ski bindings on specially designed ski plates may result in an improved release behaviour and thus potentially increase skiing safety.

Background: Among recreational skiers, ACL injury risk is about three times greater in females compared to males and female skiers suffering from ACL injury reported about 20% points more frequently a failure of binding to release compared to male skiers with an ACL injury. Performing a daily self-release test of ski bindings, however, can prevent skiing-related injuries of the lower extremity.

Aim: To evaluate to what extent uninjured male and female skiers are able to self-release their ski bindings which were recently adjusted to the ISO 11088 standard.

Methods: A total of 15 male and 15 female healthy and physically active young adults with a mean age of 23.0 ± 1.7 years and without any previous injury of the lower extremities participated in this study. Subjects had to perform an isometric leg test and the self-release test of ski bindings with both legs on a Kistler force plate. For each attempt to release the binding, torques calculated via the force plate were normalized to torques calculated by a binding adjustment system (Relative Release Torques—RRT) and represented by percentage values.

Results: Sexes significantly differ regarding body mass and BMI, but not regarding relative maximum isometric leg strength. Eleven out of the 15 male subjects (73%) and three out of the 15 female (20%) subjects released their ski bindings at least once with both legs. Regarding a total of 90 self-release trials among each sex (3 trials × 2 legs × 15 subjects), failure of binding release was significantly higher among female compared to male trials (84 vs. 54%, < 0.01). The mean relative release torques (RRT) of the 76 female trials of failure of binding release were significantly lower compared to the 49 male trials of failure of binding release (40.9 ± 20.2 vs. 50.6 ± 20.1%, = 0.009).

Conclusion: Three times more females than males were unable to self-release their ski bindings although their bindings were correctly adjusted according to the ISO 11088 standard for binding setting values. In addition, females reached about 20% lower RRT values within failure of binding release trials although males and females did not differ with regard to relative isometric leg strength.

In skiing the skier-flex pole impact causes a deflection and rotation of the flex pole and a speed loss of the skier. The purpose of the present study was to investigate the effects of skier and pole parameters on time loss, pole deflection, and pole damage speed caused by the skier-pole impact in slalom. Validated finite element models were used for the simulation of the impact. Skier mass, speed and impact height and pole mass, bending stiffness, diameter, and wall thickness were analyzed. Time loss was assessed for seven pole impacts by a simple simulation model of a skier schussing down an inclined plane. From the skier parameters, impact height followed by impact speed showed the highest effect on the skier-pole impulse. The impulse increased with increasing pole mass whereas the effect of bending stiffness was negligible. Time loss could be reduced by lowering the pole mass. However, lowering of pole diameter or wall thickness increased pole deflection enhancing injury risk due to the whiplash effect. Additionally, the reduction of wall thickness decreased pole damage speed with the disadvantage of higher risk of pole fractures. Overall, lowering pole mass for the current impact speeds in World Cup slalom races requires additional investigation. In children and youth races with lower impact speeds than in World Cup races, a pole mass reduction would be possible.