Performance and Return to Sport after Anterior Cruciate Ligament Reconstruction in Skiers and Snowboarders

Introduction

Anterior cruciate ligament (ACL) injuries are common injuries in both skiers and snowboarders. Skiers sustain ACL tears at a significantly greater rate than snowboarders. The incidence of ACL injury is increasing with time in these unique populations. Several mechanisms of ACL tear have been identified, both in the biomechanical laboratory setting and on the slopes via high-definition video analysis. A detailed history and physical examination, corroborated with an appropriate imaging evaluation, allow clinicians to reliably diagnose ACL (and potentially concomitant intra- and extra-articular pathology) injuries. Surgical reconstruction of ACL tears in recreational and elite skiers and snowboarders is highly successful, with a high rate of return to sport at the same level at short- and mid-term follow-up. In this population, the literature is replete with studies on injury epidemiology and mechanisms. However, clinical outcome studies are sparse and of low methodological quality. Future investigations should focus on improving the quantity and quality of ACL treatment in skiers and snowboarders.

Injury Epidemiology

Snow skiing and snowboarding are two of the most popular winter sports across the world. Over a single 5-month season of the International Ski Federation World Cup, one out of every three skiers sustains an injury that results in time lost from sport. Despite significant improvements in winter sport equipment and an increased understanding of injury mechanisms, ACL injuries increasingly persist as the most common severe injury in both skiing and snowboarding. There is a high incidence of ACL tear in cutting and pivoting athletes in both contact and noncontact sports, especially skiing. In skiing, nearly all ACL tears are noncontact and occur while actually skiing, and not from contact during a crash. Female skiers may also be at a significantly greater risk for ACL injuries versus males. Furthermore, in recreational female skiers, there is a significantly higher (twofold) rate of tearing the nondominant leg ACL.

The largest epidemiologic investigation of ACL injury incidence in elite skiers reported on 379 French Alpine Ski Team members that competed internationally for a minimum of one season over the time period from 1980 to 2005. At least one ACL tear was sustained by 28% of females and 27% of males, with an overall ACL tear incidence of 8.5 per 100 skier seasons. Retear of a reconstructed ACL was 19%, while the rate of contralateral ACL injury was 31%. There were significantly more ACL tears among world Top 30 skiers ( P < .001). Other investigations have revealed similar findings with regard to ACL injury epidemiology. Over seven ski seasons and over 720,000 skier days, the incidence of ACL tear in 7155 ski patrollers and instructors at a large western US ski resort was 4.2 injuries per 100,000 skier days in males and 4.4 per 100,000 in females. Over 12 seasons and 2.6 million skier days at a western US ski resort, 16% of all skiing injuries were ACL tears. Over two seasons with 661 competitive ski racers in Ski Sport Finland, the most common injury was ACL tear, with a significantly greater number of ACL injuries in females. The influence of snowboarder presence on the mountain with skiers has recently been investigated at a resort that started to permit snowboarders on the slopes with skiers. After the introduction of snowboarders, although there was a 3.1% absolute risk increase of ACL tear, with the rate increasing from 29.7% to 32.8%, the rate increase was not statistically significant.

Injury patterns in snowboarders have historically been different than that of skiers. Developed in the 1960s, snowboarding has become an incredibly popular winter sport. In the United States, approximately 11.5 million people participate in skiing, while 8.2 million people participate in snowboarding. In the Winter Olympics and the Winter X Games, snowboarding continues to be one of the most popular events. Although several investigations compare overall injury rates and locations among snowboarders and skiers, ACL injury comparisons are sparse. In a northeastern US ski and snowboard resort, the overall mean days between injuries (skier or snowboarder days) (surrogate for injury rate) was 345 for snowboarders and 400 for skiers, indicating a greater overall injury rate for snowboarders. However, ACL injury rates were over 10 times higher in skiers, with 17% of skiers and 1.7% of snowboarders sustaining an ACL tear. The prevalence of ACL injury was 21% of all injuries in skiers, but only 2% of all injuries in snowboarders.