Background and purpose: The ability to successfully self-release the ski binding can prevent skiing-related injuries of the lower extremities. Failure of binding release associated with a knee injury is significantly higher among females compared to males. The International Standards Organization ISO 11088 standard for binding setting values allows a lowering by 15% upon request of the skier. Thus, the aim of this study was to evaluate the impact of lowered ski binding settings by 15% on the outcome of the self-release test among female recreational skiers.
Materials and methods: In this randomized single-blinded study, a cohort of 20 females (24.5±2.7 years) performed the self-release test in the laboratory thrice with each leg under two conditions: 1) with an actual ISO 11088 setting and 2) with a setting lowered by 15%. For each attempt, torques calculated via the force plate were normalized to torques measured by a binding adjustment system (relative release torque, RRT).
Results: Among 240 trials in total, more females were significantly able to self-release their ski bindings with lowered binding settings when compared to their actual ISO settings (53% vs 9%, p<0.001). Thirteen females (65%) were able to release their bindings at least once with both legs with lowered binding settings compared to only three females (15%) with their actual binding settings (p<0.001). Mean RRT of all failure of binding release trials significantly differed between lowered and actual binding settings (58.6%±22.2% vs 50.5%±20.4%, p=0.003).
Conclusion: Four times more females were able to self-release their ski bindings at least once with both legs with a 15% lowered binding setting compared to their normal ISO 11088 setting. The fact that the ISO standard accepts a lowering by 15% upon request of the skier could represent an important measure to prevent knee injuries, especially for female recreational skiers.
Keywords: knee injury; lowered ski binding settings; prevention; recreational skiing; self-release test.