Nordic ski jumping injuries. A survey of active American jumpers.

Little data are available in the medical literature on nordic ski jumping injuries. Injury questionnaires were sent to all active American ski jumpers registered either with the United States Ski Association or with a jumping club registered with the United States Ski Association. One hundred thirty-three of 286 (46.5%) injury questionnaires were returned. Eighty-one of the 133 respondents (60.9%) had been injured sufficiently to require examination by a physician at least once during their jumping careers. This report describes the types and frequencies of injuries sustained by this group of nordic ski jumpers as well as provides demographic data about American ski jumpers. The risk of injury per 100 participant years was 9.4, a rate less than that reported for most high school or college intermural sports.     

Injuries among World Cup ski and snowboard athletes

There is little information available on injuries to World Cup skiers and snowboarders. The aim of this study was to describe and compare the injury risk to World Cup athletes in alpine skiing, freestyle skiing, snowboarding, ski jumping, Nordic combined and cross country skiing. We performed retrospective interviews with the International Ski Federation (FIS) World Cup athletes from selected nations during the 2006–2007 and 2007–2008 winter seasons and recorded all acute injuries occurring during the seasons. We interviewed 2121 athletes and recorded 705 injuries. There were 520 (72%) time‐loss injuries and 196 (28%) severe injuries (absence >28 days). In freestyle skiing, alpine skiing and snowboarding, there were 27.6, 29.8 and 37.8 time‐loss and 14.4, 11.3 and 13.8 severe injuries per 100 athletes per season, respectively. In Nordic combined, ski jumping and cross country skiing, there were 15.8, 13.6 and 6.3 time‐loss and 3.3, 5.6 and 0.7 severe injuries per 100 athletes per season, respectively. In conclusion about 1/3 of the World Cup alpine, freestyle and snowboard athletes sustain a time‐loss injury each season, while the risk is low in the Nordic disciplines. A particular concern was the high proportion of severe injuries observed among alpine, freestyle and snowboard athletes, which is in contrast to most other sports.     

Serious ski jumping injuries in Norway

Injuries caused by ski jumping have been poorly investigated. Among approximately 2,200 licensed jumpers in Norway, there occurred at least 12 injuries with a permanent medical disability of greater than or equal to 10%. The risk of being seriously injured is approximately 5% in a 5 year period (1977 to 1981); it is higher in the age group 15 to 17 years. Seven injuries were very serious [four central nervous system (CNS) lesions, two leg amputations, and one blindness of one eye], and five were less serious (sequelae to fractures of the lower extremities). The first jump of the day is particularly dangerous, and so is the beginning and end of the season. It seems dangerous to use more than one standard heel block. Poor preparation of the jump may have contributed to the accidents. Based on the findings, several prophylactic measures are suggested.     

Recording injuries among World Cup skiers and snowboarders: a methodological study

No long‐term injury surveillance programs exist for competitive skiing or snowboarding. The objective of this study was, therefore, to compare different methods to record injuries among World Cup athletes in alpine, freestyle, and cross‐country skiing, snowboarding, ski jumping and Nordic combined. Information regarding injuries sustained during the 2006–2007 winter season was recorded through three separate and independent systems: prospective injury reports by technical delegates (TD) from the International Ski Federation, prospective medical team registration by selected teams, and retrospective athlete interviews at the end of the season. A total of 100 unique injuries to 602 World Cup athletes were identified from any of the three recording methods. Of these, 91% were registered through the athlete interviews, 47% by the medical team registration and 27% by the TD reports. Only 20 injuries (20%) were captured by all three methods. A total of 64 time‐loss injuries were registered. The interviews captured 60 (94%), the medical team registration 39 (61%), and the TD reports 23 (36%) time‐loss injuries, while 18 (28%) were registered by all three systems. Retrospective interviews with athletes/coaches regarding injuries during the last 6 months gave the most complete picture of injuries to World Cup skiers and snowboarders.     

Jumpers and fallers: a comparison of the distribution of skeletal injury

AIM: The aim of this study was to compare the distribution of injuries between patients who have fallen and those who have jumped from a height, and to relate the mechanism of injury to the fractures sustained. MATERIALS AND METHODS: Three hundred and ninety-nine patients, admitted via Helicopter Emergency Medical Service (HEMS), classified as either having fallen or jumped from a height were included in the study. The radiographs from the primary survey, together with radiographs of specific injury sites were analysed. The distribution of injury was compared in the two groups. RESULTS: Of the 399 patients, 342 were fallers and 57 were jumpers. Jumpers had a higher Injury Severity Score (ISS), death rate and number of fractures per person. Jumpers sustained more rib fractures (particularly on the right), pelvic and lower limb fractures but fewer skull fractures. CONCLUSION: Jumpers tend to sustain different injuries to fallers. It is proposed that jumpers have a tendency to land feet-first and then try to break their falls on their dominant side, sustaining more right-sided rib fractures in the process. The patterns of injury that have emerged from this study have important implications for evaluating skeletal injuries in those who jump or fall from a height.     

Cross-country skiing injuries and biomechanics

Cross-country skiing exercises most of the joints, muscles and tendons in the body giving the skier an all around workout. This, in combination with a low incidence of injury, makes cross-country skiing an ideal recreational and competitive sport. The new skating techniques developed during the last decade have resulted in greater velocity. The maximum speed during the diagonal stride technique is 6 m/sec compared to 8 to 9 m/sec when skating and double poling. Top-level skiers today use strong and ultra light skis of fiberglass and graphite. The ski weight is less than 500g. Today's skating technique does not require any waxing and only the cambered portion of the ski is waxed when performing the diagonal stride. The preparation of the ski course has improved with the development of special track machines. This allows top-level skiers to reach 60 to 80 km/h on downhill slopes, which has resulted in an increased risk of injury. Because cross-country skiing takes place wherever snow is available, it is difficult to establish accurate injury rates in comparison to alpine skiing which is performed on very specialised terrain at ski areas. Studies estimate the cross-country ski injury rate in Sweden to be around 0.2 to 0.5 per thousand skier days. A prospective study of cross-country ski injuries conducted in Vermont revealed an injury rate of 0.72 per thousand skier days. 75% of the injuries sustained by members of the Swedish national cross-country ski team during 1983 and 1984 were overuse injuries while 25% resulted from trauma. The most common overuse injuries included medial-tibial stress syndrome, Achilles tendon problems and lower back pain. Most common among traumatic injuries were ankle ligament sprains and fractures, muscle ruptures, and knee ligament sprains. Shoulder dislocation, acromioclavicular separation and rotator cuff tears are not infrequent in cross-country skiing. Injuries to the ulnar collateral ligament of the metacarpal phalangeal joint of the thumb (Stener's lesion) is the most common ski injury involving the upper extremity. Cross-country skiers 16 to 21 years of age complained more frequently of mild lower back pain than similarly aged non-skiers. This may result from repetitive hyperextension motions during the kick phase and the recurring spinal flexion and extension during the double poling phase. Repeated slipping on hard and icy tracks infrequently produce partial tears or microtrauma in the muscle tendinous units of the groin.(ABSTRACT TRUNCATED AT 400 WORDS)     

Alpine ski injuries and their prevention

Alpine skiing is a popular sport with significant risk of injury. Since the 1970s, injury rates have dropped from approximately 5 to 8 per 1000 skier-days to about 2 to 3 per 1000 skier-days. The nature of the injuries has also been transformed over the same period. Lower leg injuries are becoming less common while the incidence of knee sprains and upper extremity injuries is becoming more common. Much of this change can be attributed to advancements in binding technology, which effectively reduces lower leg injury, but does not adequately address the issue of knee sprains. Along with design, binding adjustment and maintenance are important preventative factors. Poorly adjusted bindings have been correlated with increased injury rates. Upper extremity injuries constitute approximately one-third of skiing injuries, with ulnar collateral ligament sprains and shoulder injuries being the most common. Strategies to prevent these include proper poling technique and avoidance of non-detachable ski pole retention devices. Spinal injuries in skiers have been traditionally much less common than in snowboarders, but this disparity is likely to diminish with the recent trend of incorporating snowboarding moves into skiing. Strategies to help reduce these injuries include promoting the development of terrain parks and focussing on proper technique during such moves. Head injuries have been increasing in incidence over recent decades and account for more than half of skiing-related deaths. The issue of ski helmets remains controversial while evidence for their efficacy remains under debate. There is no evidence to demonstrate that traditional ski instruction reduces injury frequency. More specific programmes focussed on injury prevention techniques are effective. The question of pre-season conditioning to prevent injuries needs further research to demonstrate efficacy.     

Underweight in ski jumping: The solution of the problem

Underweight is becoming increasingly prevalent in many sports. Among world class ski jumpers, the body mass index BMI has decreased by 4 units since 1970. The BMI ignores different body properties of individuals. Particular care should be taken in groups with unusual leg length to avoid classifying them inappropriately as thin or overweight (WHO). The improved measure MI (mass index) for relative body weight overcomes this shortcoming. Anthropometric data of ski jumpers was collected during the Olympic Games in Salt Lake City (2002; participation 81 %, n = 57), during the Summer Grand Prix in Hinterzarten (2000; participation 100 %, n = 92), and during the World Cup in Planica (2000; n = 56). The BMI and the MI were determined. The MI considers the individual leg length: A person with longer legs than average has an MI > BMI, and vice versa: MI = 0.28 m/s2 (m: mass in kg, s: sitting height in meters). BMI classes of ski jumpers in the season 2004/2005 were calculated from their official individual ski length limitation which is a function of their BMI. BMI means were 19.84 in Planica, 19.58 in Hinterzarten, and 19.43 kg m(-2) in SLC. Lowest BMI was 16.4 kg m(-2). The percentage of underweight ski jumpers (BMI < 18.5 kg m(-2)) decreased from 22.8 % at the Olympic Games 2002 to 8.7 % in the season 2004/2005 due to the new ski jumping regulations. The ratio s/h = C (s = sitting height, h = height, C = cormic index) ranged from 0.49 to 0.57. Accordingly, the MI values (which are leg length corrected BMI values according to MI = BMI (C /C) (k) with k = 2 and C = 0.53) deviated remarkably from BMI values. For the 49 cases with BMI or MI or both below 18.5 kg m(-2), the classification to be underweight or not changed in 69 % when the MI was used instead of the BMI. Underweight or overweight is not only a question of cut-off points; the measure used determines the classification accuracy. A substantial improvement of weight analyses in sports medicine, public health, and general medicine as well can be obtained by using the MI instead of the BMI.     

Spinal injuries in skiers and snowboarders

Spinal injuries are among the most devastating injuries associated with recreational sports. Snowboarding spinal injury patterns have not been described. During two seasons (1994 to 1995 and 1995 to 1996), 34 skiers and 22 snowboarders suffered serious spinal injuries (fracture or neurologic deficit or both) at two ski areas in British Columbia, Canada. Ski patrol records, the Provincial Trauma Database, and hospital records were reviewed. Injury rates were based on computerized lift-ticket data and a population estimate of 15% snowboarders (ski patrol observation). The incidence of spinal injury among skiers was 0.01 per 1000 skier-days, and among snowboarders was 0.04 per 1000 snowboarder-days. Mean age was 34.5 years for skiers and 22.4 years for snowboarders. Seventy percent of the skiers were men, whereas all of the snowboarders were men. Jumping (intentional jump > 2 meters) was the cause of injury in 20% of skiers and 77% of snowboarders. Neither age nor sex accounted for any significant portion of this difference. The rate of spinal injuries among snowboarders is fourfold that among skiers. Although jumping is the primary cause of injury, it is an intrinsic element of snowboarding. Until research defines effective injury-prevention strategies, knowledge of the risk of snowboarding should be disseminated and techniques for safe jumping should be taught.     

Skiing injuries during initial military nordic ski training of a U.S. Marine Corps Battalion Landing Team

During 4 weeks of military nordic ski training with 638 men, 45 skiing injuries occurred with 359 days lost from training (5.63 injuries per 1,000 skier days). Knee injuries represented 38% of total injuries, with 58% of these being medial collateral ligament sprains. Knee injuries represented a greater fraction of total injuries in the novice skier cohort than in the experienced skier cohort. All injured subjects except one responded favorably to conservative therapy available at the training facility. Despite the special rigors of military nordic skiing, the incidence and anatomic distribution of injuries is similar to that reported with civilian skiing.     

Downhill ski injuries in children and adolescents

Downhill skiing is considered to be an enjoyable activity for children and adolescents, but it is not without its risks and injuries. Injury rates now range between 3.9 and 9.1 injuries per 1000 skier days, and there has been a well documented increase in the number of trauma cases and fatalities associated with this sport. Head and neck injuries are considered the primary cause of fatal injuries and constitute 11-20% of total injuries among children and adolescents. Cranial trauma is responsible for up to 54% of total hospital injuries and 67% of all fatalities, whereas thoracoabdominal and spine injuries comprise 4-10% of fatalities. Furthermore, there has been an increase in the proportion of upper extremity trauma with acromioclavicular dislocations, and clavicle and humeral fractures accounting for the majority (22-79%) of the injuries. However, the most common and potentially serious injuries in children and adolescents are those to the lower extremity, with knee sprains and anterior cruciate ligament tears accounting for up to 47.7% of total injuries. Knee sprains and grade III ligament trauma associated with lower leg fractures account for 39-77% of ski injuries in this young population.Approximately 15% of downhill skiing injuries among children and adolescents are caused by musculoskeletal immaturity. Other factors include excessive fatigue, age, level of experience, and inappropriate or improperly adjusted equipment. Collisions and falls constitute a significant portion (up to 76%) of trauma, and are commonly associated with excessive speed, adverse slope conditions, overconfidence leading to carelessness, and behavioural patterns within and among gender. The type and severity of injuries are typically functions of biomechanical efficiency, skiing velocity or slope conditions; however, a multiplicative array of intrinsic and extrinsic factors may simultaneously be involved. Despite extensive efforts to provide a comprehensive picture of the aetiology of injury, limitations have hampered reporting. These limitations include age and injury awareness, data collection challenges, lack of uniformity in the definition or delineation of age classification and lack of knowledge of predisposing factors prior to injury.Since skill level is the primary impetus in minimising ski injuries, formal instruction focusing on strategies such as collision avoidance and helmet use, fall training minimising lower extremity trauma, altering ski technique and avoiding behaviours that lead to excessive risk are, therefore, highly recommended. Skiing equipment should be outfitted to match the young skier's height, weight, level of experience, boot size and slope conditions. Additionally, particular attention should be paid to slope management (i.e. overcrowding, trail and obstacle marker upkeep) and minimising any opportunity for excessive speed where children are present. Whether increases in knowledge, education and technology will reduce predisposition to injury among this population remains to be seen. As with all high-risk sports, the answer may lie in increased wisdom and responsibility of both the skier and the parent to ensure an adequate level of ability, self-control and simply common sense as they venture out on the slopes.     

Roentgenographic skeletal injury patterns in parachute jumping

A total of 90,000 parachute jumps made during a 1 year period resulted in 615 (0.68%) injuries secondary to jumping. Of these 615 cases, 70 jumpers (0.08%) had 71 skeletal injuries as confirmed by roentgenographic examination. Forty-one (57.7%) of the 71 injuries involved the ankle, and 12 (16.9%) were compression fractures of the thoracolumbar spine. The remaining injuries were distributed as follows: shoulder, six (8.5%); calf, six (8.5%); pelvis, 3 (4.2%); foot, two (2.8%); and thigh, one (1.4%). The various mechanisms leading to these injuries are presented.     

Upper extremity snowboarding injuries. Ten-year results from the Colorado snowboard injury survey

A survey of snowboarding injuries was conducted over 10 seasons (1988 to 1998). A questionnaire evaluating 20 variables was used to collect data from 47 medical facilities near Colorado ski resorts. A total of 7430 snowboarding-related injuries were seen. A control group consisted of 3107 noninjured snowboarders. Most of those injured were 30 years of age or younger; 74% of injuries occurred in men and 26% in women; 39% of injured snowboarders were beginners and 61% were intermediate or experts. Men rode at more advanced levels than women. Injured snowboarders were more likely than noninjured snowboarders to be beginners. There were 3645 (49.06% of total) upper extremity injuries; 56.43% were fractures, 26.78% sprains, and 9.66% dislocations. The most common site of injury was the wrist (21.6% of all snowboarding injuries). Wrist fractures (except to the scaphoid) and sprains were more common in beginners, women, and younger age groups. Intermediate and expert men were more likely to sustain hand, elbow, and shoulder injuries, as well as more severe injuries. Falling was the predominant mechanism of upper extremity injuries. Snowboarders who wore protective wrist guards were half as likely to sustain wrist injuries as those who did not wear guards.     

Plantar pressure and EMG activity of simulated and actual ski jumping take-off

Plantar pressures and activation of the four muscles (VL - vastus lateralis, GL - gluteus, TA - tibialis anterior and GA - lat. gastrocnemius) were measured from ten ski jumpers under simulated laboratory conditions with training shoes (Lab TS) and with jumping boots (Lab JB) as well as in actual hill jumping conditions (Hill). The most significant differences between measured conditions were found in muscle activation patterns and plantar pressures prior to take-off. The centrifugal force due to the curvature of the inrun under actual hill jumping conditions caused extra pressure under the fore and rear parts of the feet (P<0.001) and therefore higher activation in all muscles (P<0.001 for VL, TA and GA and P<0.01 for GL). The actual take-off was characterized by high pressure under the toes during the early phase and high pressure under the heel during the latter phase of take-off. However, this should probably he interpreted as a commonly used improper technique where the balance during take-off is not well maintained to allow effective force production. Activation of GA, especially with regard to anteroposterior pressure distribution under the feet, differed significantly between the measured conditions. The role of GA for explosive force production during ski jumping take-off is much smaller as compared to that of the knee and hip extensor muscles.     

Imaging of lower extremity trauma from Boston Marathon bombing

The goal of this study is to describe the imaging features of lower extremity blast injuries in patients encountered in the radiology departments from the Boston Marathon bombings. A total of 115 patients presented to four acute care hospitals on April 15, 2013, 43 of whom presented with lower extremity injuries and were included in this study. The imaging findings of primary, secondary, tertiary, and quaternary blast injuries were evaluated. Forty-one of 43 patients sustained secondary blast injuries to the lower extremities with 31 patients (70 %) having retained shrapnel, seven patients (16 %) having soft tissue lacerations without retained shrapnel, and ten patients (23 %) having lower extremity amputation (7 % double amputees). Eight of these patients (20 %) had lower extremity fractures, and five patients (12 %) had vascular injuries. Two of the 43 patients (5 %) had only tertiary injuries, and five of 43 patients (12 %) were noted to have lower extremity burns, consistent with quaternary blast injury. No primary blast injury occurred in the lower extremities. A vast majority of lower extremity injuries were from secondary blast injury, most commonly from retained shrapnel in 70 % of patients and 23 % of patients sustaining lower extremity amputation. Retained shrapnel in the lower extremity was most commonly ball bearings and pressure cooker fragments, and most injuries affected the leg, followed by the thigh and foot.     

In-line skating: injuries and prevention

BACKGROUND: Most reports on in-line skating injuries describe severe injuries admitted to injury clinics. Little is known about the overall rate of injury and the contribution of the different disciplines. METHODS: In a retrospective inquiry data on injuries were obtained of 105 in-line skaters of whose 69% were active in fitness skating, 59% in jumping/grinding and 51% in the halfpipe. Beside the nature, location and degree of the injury, information was given on where the injury happened and whether protectors were worn at the time of injury. RESULTS: Of 197 injuries 145 healed without medical treatment, 28 needed medical advice once, 22 several times and 2 needed hospitalisation. Injury location were 38% in the upper, 31% in the lower extremities, 21% in the hip/pelvis region and 10% on the head. The most frequent injuries pertained to concussions and skin lesions, 35% each, followed by ligament injuries with 10% and fractures with 5%. Simple injuries were 83% in fitness skating, 70% in jumping/grinding and 60% in the halfpipe. Several visits were necessary for 4% of fitness skaters, 10% of jumpers/grinders and 23% in halfpipe injured persons. All four protectors were worn at the time of injury by 5% in fitness skating, 18% in jumping/grinding and 55% in the halfpipe. No protectors were worn in 26% of the fitness injuries, in 9% jumping/grinding and in 6% in the halfpipe. CONCLUSIONS: The results reveal an apparent discipline specific degree of danger and that fitness in-line skating is less dangerous than the resulting benefits for preventive medicine.     

Costal cartilage fracture: A commonly missed thoracic injury in trauma patients

In this report, we describe a case of a 43-year-old male who sustained a displaced mid chondral costal cartilage fracture along with multiple ipsilateral rib fractures following a jet ski collision. Costal cartilage fractures (CC) are commonly missed on imaging evaluation, and accordingly underreported in the literature. High-energy blunt chest trauma represents the most common mechanism for CC injuries. Computed Tomography (CT) is the modality of choice to diagnose CC fractures along with the associated cardiopulmonary and abdominal injuries in polytrauma patients. There is currently no consensus with respect to the management of CC fractures. Further research is required to explore the long-term impact of CC fractures on thoracic cage stability.     

Gefahren im alpinen Ski-Leistungssport – Gefährdung und Gefährdungsprävention: Ein epidemiologischer Vergleich zu anderen Leistungssport-Wintersportarten und zum alpinen Ski-Breitensport

Alpine skiing is one of the most popular winter sport disciplines and professional ski racing enjoys great popularity and media exposure. Due to the already high professionalization and power density in Alpine Ski World Cup racing, success and failure are quite close to each other leading to a tremendous readiness of the athletes to assume a risk and consequently to an increased injury risk in alpine ski racing. In this overview, epidemiologic data and typical injury patterns in Alpine Ski World Cup racing will be highlighted and compared to other high-level winter sport disciplines as well as to recreational alpine skiing. In addition, a risk analysis of ski-typical injuries and categorization of preventive interventions in alpine ski racing will be performed.     

Improved safety in ski jumping

Among approximately 2,600 licensed Norwegian ski jumpers, only three injuries that caused a permanent medical disability of at least 10% were incurred during the 5 year period from 1982 through 1986. When compared to the previous 5 year period (1977 to 1981), a dramatic improvement in safety is seen, as both number and severity of such injuries were markedly reduced. There are several probable reasons for this improved safety record: better preparation of the jumps, the return to using only one standard heel block, and the fact that coaches are being more responsible, especially with younger jumpers.     

Snowboard injuries

A retrospective survey of 267 snowboarders was undertaken to determine the population at risk and types and mechanisms of injuries sustained in this sport. Snowboarders are young (average age, 21 years), male (greater than 90%), view themselves in average or above average physical condition (96%), and have varied sports interests. One hundred ten injuries that resulted in a physician visit were reported. Ligament sprains, fractures, and contusions were the most frequent types of injury. Fifty percent of all injuries occurred in the lower extremities, with ankle injuries being the most common. Snowboard riders using equipment with increased ankle support seem to be more protected from lower extremity injuries. The lower extremity injuries were concentrated in the forward limb of the snowboarder, where the rider's weight is disproportionately distributed. Differences in the mechanism and spectrum of injury between snowboarding and skiing injuries were noted, including: impact rather than torsion as the major mechanism of injury, a significant lack of thumb injuries, comparative increase in ankle injuries, a decrease in knee injuries, and a higher percentage of upper extremity injuries.