Gerhard Ruedl

Effects of modern ski equipment on the overall injury rate and the pattern of injury location in Alpine skiing.

In this article, the relationship, perhaps interdependence, between sleep-disordered breathing, hypertension, and obesity is discussed. There is strong evidence that sleep-disordered breathing and hypertension are related. On the one hand, the prevalence of hypertension increases with the number of apnea-hypopnea episodes per hour of sleep, whereas on the other hand, treating sleep-disordered breathing reduces hypertension. It has also been shown that this relationship between sleep-disordered breathing and hypertension is stronger in individuals with a high body mass index. Thus, it is concluded that in individuals presenting with hypertension, sleep-disordered breathing, or increased weight, the two other variables must be investigated and treated if present.Objective:To identify whether the introduction of carving skis and related equipment has altered the overall injury rate and/or the pattern of injury location. Design:Comparative case series. Setting:In the winter season of 1997-98, when carving skis began to appear on the ski market, all injured skiers requiring evacuation or medical treatment in 70 Austrian ski areas were recorded. Five years later, when most skiers were using carving skis, ski injury data were collected in a representative sample consisting of 5 ski areas from the first study. Assessment of Risk Factors:Data collection on injured skiers included subject demographics, weather and snow conditions, mechanism of the skiing accident, the type of ski used, injury location, and in the second study, additionally the date of the last ski binding adjustment. Main Outcome Measurements:Frequency of injured body parts. Results:In 1997-98, 1.43 injuries per 1000 skier days were calculated. Out of 17,914 injured alpine skiers, 29.5% of the injured men and 53.0% of the injured women suffered knee injuries. Five years later with the introduction of carving skis, the overall injury rate decreased by 9% but the gender-specific percentages of knee injuries did not change. Female carving skiers not using newly adjusted bindings had a higher risk of knee injury than those with newly adjusted bindings. Conclusion:The maintenance of adequate binding adjustment is especially important for the prevention of knee injuries in female carving skiers.

Injuries in judo: a systematic literature review including suggestions for prevention

Background There is limited knowledge on epidemiological injury data in judo. Objective To systematically review scientific literature on the frequency and characteristics of injuries in judo. Methods The available literature up to June 2013 was searched for prospective as well as retrospective studies on injuries in judo. Data extraction and presentation focused on the incidence rate, injury risk, types, location and causes of injuries. Results During the Olympic Games in 2008 and 2012, an average injury risk of about 11–12% has been observed. Sprains, strains and contusions, usually of the knee, shoulder and fingers, were the most frequently reported injuries, whereas being thrown was the most common injury mechanism. Severe injuries were quite rare and usually affected the brain and spine, whereas chronic injuries typically affected the finger joints, lower back and ears. The most common types of injuries in young judo athletes were contusions/abrasions, fractures and sprains/strains. Sex-differences data on judo injuries were mostly inconsistent. Some studies suggested a relationship between nutrition, hydration and/or weight cycling and judo injuries. Also, psychological factors may increase the risk of judo injuries. Conclusions The present review provides the latest knowledge on the frequency and characteristics of injuries in judo. Comprehensive knowledge about the risk of injury during sport activity and related risk factors represents an essential basis to develop effective strategies for injury prevention. Thus, the introduction of an ongoing injury surveillance system in judo is of utmost importance.

Factors associated with self-reported risk-taking behaviour on ski slopes

Background In recent years, discussions have arisen about the potential influence of wearing a ski helmet on an increasing level of risk taking and higher speeds on ski slopes. Objective To evaluate factors associated with selfreported risk-taking behaviour in recreational skiers and snowboarders. Methods Speeds of skiers and snowboarders were measured with a radar speed gun and sex, age, nationality, height, weight and helmet use, used type of gear, self-estimated skill level and self-estimated fitness level were recorded. In addition, participants were asked if they considered themselves as cautious or risk-taking skier or snowboarder. Results In total, 453 skiers (39.6 (14.8) years) and 74 snowboarders (26.4 (9.6) years) have been interviewed. A stepwise forward logistic regression model revealed five independent factors for a risk-taking behaviour on slopes. Adjusted OR and their 95% CI showed that risk takers were <40 years (OR 2.4, 95% CI 1.51 to 3.80), had a higher skill level (OR 2.1, 95% CI 1.25 to 3.50), were more likely males (OR 2.0, 95% CI 1.22 to 3.26), had a lower body mass index (22.8 vs 24.2) and skied with higher speeds (on average 53 vs 45 km/h) compared to cautious skiers. Conclusion Risk-taking behaviour on ski slopes is associated with younger age, higher skiing ability, male sex, lower body mass index and on average higher speeds. Helmet use is not associated with riskier behaviour on slopes. In addition, helmet use has to be recommended because helmet use reduces the risk of head injuries among skiers and snowboarders.

Are oral contraceptive use and menstrual cycle phase related to anterior cruciate ligament injury risk in female recreational skiers

Oral contraceptive use and menstrual cycle phase are suggested to influence the risk of anterior cruciate ligament (ACL) injuries in female athletes. However, only few data are available for recreational sports. Therefore, female recreational skiers with a non-contact ACL injury and age-matched controls completed a self-reported questionnaire relating to menstrual history, oral contraceptive use and previous knee injuries. Menstrual history data were used to group subjects into either preovulatory or postovulatory phases of menstrual cycle. Our findings suggest that oral contraceptive use did not show any protective effect against ACL injuries nor did self-reported previous knee injuries show any association with ACL injury rate in recreational alpine skiing. Analysis of menstrual history data revealed that recreational skiers in the preovulatory phase were significantly more likely to sustain an ACL injury than were skiers in the postovulatory phase.

Sport injuries and illnesses during the first Winter Youth Olympic Games 2012 in Innsbruck, Austria

Background Data on the injury and illness risk among young elite athletes are of utmost importance, because injuries and illnesses can counter the beneficial effects of sports participation at a young age, if children or adolescents are unable to continue to participate because of residual effects of injury or chronic illness. Objective To analyse the frequencies and characteristics of injuries and illnesses during the 2012 Innsbruck Winter Youth Olympic Games (IYOG). Methods We employed the International Olympic Committee (IOC) injury surveillance system for multisport events, which was updated for the Winter Olympic Games in Vancouver 2010. All National Olympic Committees (NOCs) were asked to report the daily occurrence (or non-occurrence) of newly sustained injuries and illnesses on a standardised reporting form. In addition, information on athletes treated for injuries and illnesses by the Local Organizing Committee medical services was retrieved from the medical centre at the Youth Olympic Village and from the University hospital in Innsbruck. Results Among the 1021 registered athletes (45% women, 55% men) from 69 NOCs, a total of 111 injuries and 86 illnesses, during the IYOG, were reported, resulting in an incidence of 108.7 injuries and 84.2 illnesses per 1000 registered athletes, respectively. Injury frequency was highest in skiing in the halfpipe (44%) and snowboarding (halfpipe and slope style: 35%), followed by ski cross (17%), ice hockey (15%), alpine skiing (14%) and figure skating (12%), taking into account the respective number of participating athletes. Knee, pelvis, head, lower back and shoulders were the most common injury locations. About 60% of injuries occurred in competition and about 40% in training, respectively. In total, 32% of the injuries resulted in an absence from training or competition. With regard to illnesses, 11% of women and 6% of men suffered from an illness (RR=1.84 (95% CI 1.21 to 2.78), p=0.003). The respiratory system was affected most often (61%). Conclusions Eleven per cent of the athletes suffered from an injury and 9% from illnesses, during the IYOG. The presented data constitute the basis for future analyses of injury mechanisms and associated risk factors in Olympic Winter sports, which, in turn, will be essential to develop and implement effective preventive strategies for young elite winter-sport athletes.

Self reported risk taking and risk compensation in skiers and snowboarders are associated with sensation seeking

In alpine skiing, a controversial discussion has been taking place regarding the potential influence of wearing a ski helmet on the individual level of risk taking behaviour. The aim of this study was to evaluate whether self reported risk taking behaviour and self reported risk compensation are associated with the personality trait sensation seeking (SS) in alpine skiing and snowboarding. In total, 683 persons (36% males and 64% females) completed an online-survey about attitudes and use of protective gear in winter sports including the German version of the sensation seeking scale form V. A logistic regression analysis including gender, age, nationality, preferred winter sport, self reported skiing ability, mean skiing time per season, use of ski helmets, and SS total score was used to estimated adjusted odds ratios (ORs) and their 95% confidence intervals (95 CI) for self reported risk taking behaviour. Regression analysis revealed that a more risky behaviour increased with male gender (OR: 2.7), with an age<25 years (OR: 1.6), with skiing (OR: 1.3), higher skill level (OR: 5.7), and a mean skiing time>28 days per season (OR: 2.2). In addition, SS total score was significantly higher in more risky compared to more cautious people (23.8 vs. 20.3, p<.001). Ski helmet use was not found to be predictive for a more risky behaviour (p>.05). Also, skiers and snowboarders with self reported risk compensation while wearing a ski helmet had higher SS total scores compared to those who did not report risk compensation (23.8 vs. 20.9, p=.001). In addition, self reported risk compensation in helmet wearers increased with an age<25 years (OR: 2.2), a higher skill level (OR: 2.5) and a mean skiing time>28 days per season (OR: 2.1). In conclusion, self reported risk taking and self reported risk compensation are associated with higher sensation seeking total scores. The personality trait sensation seeking, not wearing of a ski helmet, appears to be associated with riskier behaviour on the ski slopes.

Leg Dominance Is a Risk Factor for Noncontact Anterior Cruciate Ligament Injuries in Female Recreational Skiers

Background: In recreational alpine skiing, the knee joint accounts for about one third of all injuries in male and female skiers. However, female recreational skiers have twice the knee injury incidence of male skiers, and the anterior cruciate ligament (ACL) injury risk is 3 times greater in female skiers. Purpose: To evaluate whether leg dominance is a risk factor for noncontact ACL injuries in female recreational skiers. Study Design: Cohort study; Level of evidence, 3. Methods: The relationships between leg dominance, side of knee injury, and gender were analyzed in 65 male and 128 female skiers suffering from a noncontact ACL rupture. Results: Anterior cruciate ligament ruptures of the left knee occurred more frequently in female than in male recreational skiers (68% vs 48%, P = .006). For both genders, in 90%, the right leg was the preferred kicking leg. With regard to leg dominance, female skiers suffered more often from ACL ruptures of their nondominant leg than male skiers (63% vs 45%, P = .020). An adjusted odds ratio of 2.0 (95% confidence interval, 1.0-3.8) was calculated. Conclusion: Female skiers showed a 2-fold higher risk of suffering from an ACL rupture on their nondominant leg. Therefore, leg dominance seems to be a risk factor for noncontact ACL injuries in female recreational skiers.

ACL Injury Mechanisms and Related Factors in Male and Female Carving Skiers: A Retrospective Study

In recreational alpine skiing, ACL injury risk is 3 times greater in females. However, since the introduction of carving skis ACL injury risk seems to have decreased. No study has yet investigated the distribution of ACL injury mechanisms in male and female carving skiers. Therefore, the aim of the study was to investigate potential gender specific differences of ACL injury mechanisms and related factors among carving skiers. In total, 220 recreational carving skiers (59 males and 161 females) suffering from an ACL injury volunteered for this study. Demographic data, skiing ability, equipment related and environmental factors, circumstances and causes for the fall, and type of fall (injury mechanisms) were collected by questionnaire. The forward twisting fall is the most reported ACL injury mechanism in both gender (p=0.672) accounting for 54% of all injuries, although male and female skiers differed significantly with regard to circumstances of fall (p=0.001) and actions when ACL injury occurred (p=0.04). Bindings not releasing at the time point of accident occurred 2.6 times more with females than with males (p=0.005). The forward twisting fall seems to have become the dominant ACL injury mechanism both in male and female recreational skiers since the introduction of carving skis.

Factors associated with injuries occurred on slope intersections and in snow parks compared to on-slope injuries

In alpine winter sports, external risk factors as snow and weather conditions as well as slope characteristics (width, steepness, slope intersections, and snow parks) should be considered when investigating potential risk factors. Therefore, ski patrol injury reports were used to compare factors associated with injuries occurred on slope intersections and in snow parks compared to on-slope injuries. Multivariate regression analysis revealed that in comparison to injuries occurring on ski slopes, collisions with other persons (OR: 2.1, 95% CI: 1.3-3.4) and arm injuries (OR: 2.1, 95% CI: 1.3-3.5) were more likely associated with injuries occurring on slope intersections while male gender (OR: 3.5, 95% CI: 2.1-5.7), younger age (OR: 1.1, 95% CI: 1.0-1.1), slushy/soft snow conditions (OR: 1.9, 95% CI: 1.1-3.3), knee injuries (OR: 0.4, 95% CI: 0.2-0.8) and back injuries (OR: 5.5, 95% CI: 3.0-10.2) were more likely associated with injuries which occurred in snow parks. In conclusion, injuries on slope intersections and in snow parks differ in some factors from injuries sustained on ski slopes.

Impact of environmental factors on knee injuries in male and female recreational skiers

In alpine skiing, the knee represents the dominant injury location with marked gender differences. Snow, slope and weather conditions as well as altitude and low temperatures are thought to influence the prevalence of knee injuries. Therefore, ski patrol injury reports were used to compare gender‐specific prevalence of knee injuries with regard to several environmental factors including the actual air temperatures. A total of 1039 non‐contact knee injuries were reported with a corresponding prevalence of knee injuries of 44.4% (males: 30.1%; females: 57.4%). Temperature quartiles of all recorded injuries were calculated to compare gender‐specific prevalence of knee injury with regard to temperatures. Comparing the first quartile (mean temperature −11 °C) with the fourth quartile (mean temperature +3 °C), the prevalence of knee injury in female skiers was higher at low ambient temperatures (61% vs 50%, odds ratio: 1.60, 95% confidence interval: 1.16–2.22; P=0.005) while no such association was found for male skiers. Additionally, knee‐injured females showed a twofold prevalence when skiing during snowfall compared with females with other injuries (15.4% vs 8.6%; P=0.001). No other environmental factor showed a significant association with the gender‐specific prevalence of knee injury. In conclusion, low ambient temperature and snowfall are important environmental risk factors for knee injuries in female skiers.