Technical possibilities for optimising the ski-binding-boot functional unit to reduce knee injuries in recreational alpine skiing

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 selfrelease 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%, p < 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%, p = 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.

Section: Discussionmentioning

confidence: 99%

Self-Release of Ski Bindings: A Sex Comparison

Posch

Ruedl

Eberle

et al. 2017

“…Further public education on safe ski-binding set-up is needed. Researchers working with ski equipment manufacturers also need to continue the quest for solutions that will protect the knee whatever the direction of the injurious force [17,18].…”

Section: Discussionmentioning

confidence: 99%

New Zealand Snow Sports Injury Trends Over Five Winter Seasons 2010–2014

Costa-Scorse

Hopkins

Cronin

et al. 2017

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 nonrelease 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

“…In practice, the ski binding is exposed to three-moment and three-force components. Ideally, the ski bindings should have a release mechanism that can be triggered by any of these mechanical parameters at excessive (injury level) loads [18]. The official requirements and test methods for the ski bindings are described by the International Standardization Organization (ISO) under the ISO 9462:2014 standard.…”

Section: Methodsmentioning

confidence: 99%

“…With the background of this unchanged high knee injury rate a recent study investigated the potential role of the ski-binding-boot functional unit to decrease the injury risk of lower extremities [18]. It concluded that the biggest potential to decrease the injury rate was to develop more sophisticated safety release bindings, i.e.…”

Section: Introductionmentioning

confidence: 99%

“…Ski plates have been primarily propagated to influence a bending line and the damping behaviour of the ski as well as the boot-out at large ski inclinations [18]. Recently, a platform for mounting the binding on a ski (Allflex plate, Allflex ski and snowboard plates, Slovenia) with a unique patented construction [20] has been introduced to the market.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Special Design of Ski Plates May Improve Skiing Safety

Supej

Senner

2017

Self Cite

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, skideflection 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.