Alpine Injuries - how are we injuring ourselves?

Snow sports are a crucial part of the adventure tourism industry in New Zealand, and a very popular recreational sport among many age groups. Unfortunately, injuries sustained up on the snow are very common, and these can range from mild sprains and contusions to severe catastrophic trauma, and in very rare cases even death.

Beginners, recreational skiers, advanced skiers and alpine racers all are at risk of significant injury that can cause a big impact to their livelihood.

Over recent years research into alpine injury epidemiology, injury aetiology, alpine ’prehab’ and injury prevention has been plentiful. Injury rates in snowboarders remain higher than in skiers with at least twice the injury rate seen in snowboarding than skiing. The wrist, shoulder and ankle are more common in snowboarders with knee ligamentous injuries being most common in skiers. In snowboarding 75% of the injuries occur in the front leg and beginner snowboarders are far more likely to be injured. Equipment failure in snowboarding is far less likely to cause injury than equipment failure in skiing.

This article looks at the most common injuries sustained on the ski field.

The knee

Knee injuries account for 20-35 % of all injuries, with the knee more likely to be injured in skiing than while snowboarding. Over the past 50 years, the development of better bindings, stiffer boots to assist stabilising and protecting the ankle has reduced the overall incidence of lower leg injuries but can increase the load on the knee.

According to recent studies, the MCL is the most commonly injured ligament in the knee with Grade 1-2 MCL injuries accounting for the largest number of presentations. This is closely followed by ACL injuries. In my practice, I am far more likely to see a skiing-related ACL rupture than an isolated MCL injury and that probably reflects that MCL sprains less commonly trigger specialist referral. Meniscal injuries are also common, with or without ligamentous injury.

In recreational skiers, the ACL rupture generally occurs when trying to get up from a fall whilst still moving, recovering from an off-balance position, or trying to lean back and sit down when losing control. The downhill ski often falls inwards and the quadriceps contracts with pulls the tibia forward and a valgus/pivot shift mechanism can occur. The newer carving skis are shorter than traditional skis, and may cause more of a forward twisting fall. In snowboarding, there are fewer knee injuries as having both feet anchored there is less of torsional force that can be applied.

In the elite skiers, the knee is also the most commonly injured; true for both females and males and accounting for approximately 40% injuries sustained in world cup racing. Bere et al (2011 AJSM) found the ‘slip-catch’ mechanism to be the most common with the outer ski losing contact with snow during turn and the skier tries to reach out and extend knee to place it down with the inside edge catches abruptly causing flexion, valgus and internal rotation

Body parts injured in elite world cup skiers:

Florenes et al (BJSM 2009) looked at injuries among male and female world cup alpine skiers and found the risk of injury is even higher than previously reported. As the above graph demonstrates the knee Is most frequently injured; and many of these are severe injuries.

The injury rate was higher with increasing speed with;

  1. Slalom skiing reporting 4.9 injuries per 1000 runs
  2. Giant slalom 9.2 injuries per 1000 runs
  3. Super-G 11.0 injuries per 1000 runs
  4. Downhill 17.2 injuries per 1000 runs.

This study confirmed the most frequently injured body part was the knee, with 68 injuries (36%), and 37 of these were severe. The overall injury rate was higher in males than in females, but not for knee injuries which is also reflected in the above graph.

The Ankle

The ankle accounts for about 5% of all skiing injuries, and generally associated with bindings not releasing, or boots that are not the correct height. Hard shell boots have higher incidence of tib/fib fractures above the level of the boot. Soft shall boots are associated with more ankle injuries. In snowboarding, ankle injuries account for about 30% of all injuries, with 4x the incidence of skiing.

Sprains are most common, and fractures may also be seen with the lateral talar process; a fracture easily missed. This occurs with a forceful dorsiflexion +/- inversion/eversion mechanism when landing heavily. Plain films are recommended as a good first step when this injury is suspected to assist diagnosis with this injury being prone to nonunion and avascular necrosis.

Upper Limb Injuries

These are about 3 x more common in snowboarding than in skiing. The lack of poles and fixed feet leads to the upper limb absorbing the forces from a fall. 50% of the upper limb injuries are likely fractures with the wrist consisting of 25 % of the total injuries. Wrist guards have reduced the incidence of hand/wrist injuries significantly. But

Shoulder injuries are common with contusion, rotator cuff injury, traumatic instability, clavicle fractures and greater tuberosity fractures all being frequently seen. .

Injuring the spine and back (and coccyx) is more common in snowboarders relating to falling mechanics, as snowboarders generally fall backwards increasing the axial loading through the spine. Fractures of the spine and coccyx are more common in osteoporotic skiers.

Head injuries and concussion also occur with reasonable frequency up the mountain. The injury rate is about 10% of all injuries, and tends to be higher in males and in snowboarders. Pleasingly there has been a huge shift toward wearing helmets, and aside from adding lots of head warmth, they are thought to reduce head injury risk by 30-35%; and even more so in children.

Cross-country skiing is far more common in the northern hemisphere, but there are increasing number of people heading up for the endurance ‘burn’ that cross-country skiing provides. Injury rate is far less with injuries occurring 0.5-5 per 1000 skier days. In the upper limb, the most common injury is the UCL thumb injury from ski pole planting accidents. High loads are put through both the quadriceps and hamstrings with the MCL and ACL are still the most common lower limb ligamentous injuries and usually due to catching the ski tip in the snow. There is a higher incidence of ankle sprains then downhill skiing due to the boot design and also the increased repetitive plantarflexion required.

Overuse injuries are also common in all of the above, with this mainly occurring in the lower limb. Most common is metatarsalgia, retrocalcaneal bursitis, patellofemoral pain, and glut med tendinopathy.

  1. BERE, T et al. Mechanisms of anterior cruciate ligament injury in World Cup alpine skiing. Am J Sports Med 2011; 39: 1421-9
  2. FLORENES et al. Injuries among male and female World Cup alpine skiers. Br J Sports Med 2009;43:973–978
  3. Sulheim et al Risk factors for injuries in alpine skiing, telemark skiing and snowboarding—case-control study. Br J Sports Med 2011;45:1303–9.