The incidence of anterior cruciate ligament injuries among competitive Alpine skiers: a 25year investigation

Alpine skiing is the most popular winter sport in the world. For nearly 40 years, progress in quality ski equip-ment and considerable improvement of ski boots and bind-ing systems contributed to the reduction of many injuries (50 % less since 1972).3 Leg and ankle injuries particularly decreased,2 but serious knee ligament sprains have risen dramatically.4,24 Ten percent of all the accidents in snow skiing involve an anterior cruciate ligament (ACL) injury,18 which is twice more than in 1970.6 Forty-five per-cent to 60 % of knee injuries during alpine skiing involve an ACL injury.6,18 Various mechanisms could cause an ACL injury during skiing.27 The boot-induced anterior drawer mechanism during hard landings after a jump is common among high-level alpine skiers.24 When the top of the ski boot drives the tibia forward, the skier assumes a characteristic seated position. This produces an anterior-directed force on the tibia relative to the femur, which is incompletely controlled by a massive quadriceps contraction.19 This mechanism of ACL injury in elite alpine skiers is distinct from that of the recreational skier, which typically involves a combined val-gus and internal rotation tibial force