Oh Knee, Oh My: An Inadvertent ExperimentOver the past several years, ski manufacturers have introduced skiboards, little skis¿usually no more than 100 centimeters long¿with nonreleasable bindings. They have been surprisingly popular. They've also amounted to what Jasper Shealy calls a "gruesome, serendipitous experiment." Because when Ettlinger, Shealy, and Johnson decided to track injuries on these devices, they discovered that skiboarders are more likely to sustain a lower-leg injury (fractured tibia, etc.) than skiers were at any time in their research, going all the way back to 1972. But at the same time, skiboarders are at extremely low risk for ACL injury.
Since skiboard bindings don't release, this suggests that binding release plays very little role in preventing ACL injuries. What then accounts for the decrease in ACL sprains? Skiboards have no tail to speak of, so no Phantom Foot, no Boot Induced ACL injury. But the lack of release, despite the lack of length, has proved a real danger to the lower legs of skiboarders. The conclusion: Release bindings are critical for protecting the lower leg, but not the knee; and the tail of the ski plays a crucial role in the injury of the ACL.