[Increasing incidence of knee ligament injuries in alpine skiing: epidemiology and etiopathogenetic hypotheses].

20 to 25% of all the injuries are due to traumas of the knee since forty years. The amount of serious sprains has been in constant increasing during the last four decades. The ratio of one to two in 1960 between and ankle injuries was of six to one in 1987. The inversion of this ratio is probably due to the evolution of technics from 1960 forth, to plastic shoes with thicker soles, to the wrong adjustment of binding and to the higher speed of the skiers thanks to better mending of tracks. The frequency of injury of ligamental structures is higher for the internal lateral ligament and for the anterior cruciate ligament. A valgus associated to internal leg rotation in consequence of blocking of internal edge and of forward falling causes internal lateral ligament injury. The three lesional mechanisms of the anterior cruciate ligament are the valgus connected with external rotation, the anterior draw caused by the shoe in case of backward falling and the association valgus-flexion-internal rotation ("foot-phantom"). These lesions of ligaments are often connected with lesions of the external meniscus and with osseous contusions concerning the external femoral condyle and the external tibial plate.