Analysis of skiing accidents involving combined injuries to the medial collateral and anterior cruciate ligaments.

Two types of ligament injuries common in skiing are the isolated ruptures of the anterior cruciate and ruptures of the medial collateral, either with or without rupture of the anterior cruciate. Based on research related to ligament injury mechanics and two-mode release binding function, the purpose of this paper was to critically assess the ability of two-mode release bindings to prevent combined medial collateral and anterior cruciate ligament injuries. Making this assessment entailed several steps. First, I determined the loads typically transmitted by the knee during falls in which combined injuries occurred. Because more than one load was transmitted, the next step was to discern which of the loads was more damaging. Finally, heel-toe type bindings were evaluated for their potential to release in response to damaging loads. I concluded that combined medial collateral and anterior cruciate ligament injuries typically occur in forward, twisting-type falls in which the primary loads are external axial and valgus moments. An external axial moment is more damaging than a valgus moment, both to the medial collateral ligament when the joint is intact and to the anterior cruciate ligament when the medial collateral ligament is damaged. Because heel-toe type bindings offer release sensitivity to this moment, the release level of the toepiece in twist is an important factor in the prevention of these injuries.