Jan R. Idzikowski, PA-C, Peter C. Janes, MD, Paul J. Abbott, MD*
Abstract
A prospective study of snowboarding injuries was conducted over eight seasons. A total of 4390 injuries in 4154 patients were seen. There were 1974 injuries to the upper extremity (UE). Forty-five percent of UE injuries (873), and 20% of all snowboarding injuries were to the wrist. The majority of these were fractures (78%). Wrist fractures and sprains occurred predominantly in beginner snowboarders. Eleven percent of wrist fractures were growth plate injuries. Twenty-eight percent of all injuries in beginners are distal radius fractures. Intermediate and expert riders suffered more severe fractures, most of the scaphoid fractures and all of the 12 perilunate or lunate dislocations. Distal radius fractures and sprains were nearly twice as likely to be the result of a backward fall than a forward fall. Snowboarders who wore protective wrist splints had a 50% reduction in the incidence of wrist fractures and sprains. None of the dislocations occurred in those who wore splints. Because of the relatively high prevalence of wrist injuries in snowboarders, especially in beginners and skeletally immature riders, we strongly advocate the use of protective wrist splints for all snowboarders and continuing research and development of these devices.
Keywords: snowboarding, wrist injuries, distal radius fractures
Introduction
The popularity of snowboarding continues to burgeon. An informal survey of Colorado resorts after the 1995-1996 season revealed that 9-16% of participants at their facilities were snowboarders. The 1994-95 NSAA Kottke National Business Survey indicated that 14% of the 54 million ski area visits in the United States were generated by snowboarders [1]. Other industry analysts project that, with present growth rates, more than 40% of those on the slopes will be snowboarders by the year 2000. We are in the ninth year of an ongoing prospective study of snowboarding injuries in Colorado in order to assess injury patterns, compare results with previous studies, identify trends or changing injury patterns associated with newer equipment technology and to determine the efficacy of protective equipment. This presentation addresses wrist and hand snowboarding injuries.
Methods and Materials
The study period spanned eight snowboarding seasons (1988 through 1996). An optically scanable bubble-form questionnaire evaluating twenty variables including stance, equipment used, mechanism of injury, and experience level was completed for all snowboard injuries seen at thirty-two medical facilities near Colorado ski areas during the study period. A control group of non-injured snowboarders was not evaluated. Previous studies [2-7] have demonstrated a relatively high incidence of wrist injuries to snowboarders, therefore attention was focused on these injuries and the possible impact of the use of protective wrist splints on the rate of wrist injury. SPSS software was used to perform statistical analysis on all data.
Results
A total of 4390 snowboarding injuries were seen in 4154 patients. There were 1974 injuries to the upper extremity, or 45% of all snowboarding injuries. The majority of injuries to the UE were fractures (57%) followed in frequency by sprains (25%), dislocations (11%), contusions (6.4%) and lacerations (0.6%) (Figure 2). The wrist accounted for 45% of UE injuries (Figure 3). The shoulder and clavicle were injured 31.3% of the time followed by the hand (9.5%), elbow (7.2%), forearm (6.4%) and humerus (0.6%).
Snowboarders in this study were primarily young males. Most were 29 years or younger (87%) with an average age of 22 (Figure 4). Nearly 20% were skeletally immature. The average age of snowboarders increased during the study period from 19.9 to 23.5 years (Figure 5). Seventy-four percent of the injured were male and twenty-six percent were female. Gender demographics did not change significantly during the study period.
Forty percent considered themselves beginners whereas sixty percent were intermediate and expert riders (Figure 6). A higher percentage of snowboarders considered themselves intermediate and expert as the seasons progressed. Males generally rode at more advanced levels than females (67% intermediate and expert vs. 37%, respectively) (Figure 7).
Eighty-one percent of all snowboarding injuries were the result of a fall, about 9% were from a collision, the rest from a twist or lift mishap (Figure 8). However, over 92% of UE injuries were due to a fall. Of these, 58% fell forward and 42% fell backward. The direction of the fall was predictive of the anatomical site injured (Figure 9). Shoulder injuries were more often associated with a forward fall, and wrist injuries more commonly the result of a backward fall. Neither gender nor experience level correlated with the direction of fall.
Mechanism of injury varied with ability level, age and gender. A higher percentage of beginners and those aged 10-19 injured themselves from a fall or a lift mishap as compared to more advanced ability levels (Table 1). Conversely, 90% of collisions were seen in intermediate and expert riders and 20-29 year-olds.
As recognized by other studies [8,9], we did note some specific gender differences (Table 2). Males as a group seemed to ride more aggressively than females at all levels of experience. They were more likely to collide with trees (90% of collisions vs. 10%), injure their shoulders (dislocations, A-C separations and clavicle fractures) and elbows and to sustain more severe injuries than females. Women, on the other hand, sustained more than the expected number of wrist fractures and sprains (38% and 47%vs expected 26%), excluding scaphoid fractures. When gender-related variance in ability level was considered, these differences in injury rates were mostly, but not entirely, eliminated. This was particularly apparent for shoulder injuries in males.
The foot that was positioned forward on the snowboard was associated with a slightly higher percentage (56%) of same side UE injuries with some exceptions. Shoulder dislocations, both bone forearm fractures, distal radius fractures and wrist sprains were all twice as likely to occur on the side opposite of the foot forward. There was no correlation between hand dominance and side of injury.
The Wrist
There were 873 wrist injuries in the series, making the wrist the most common anatomic site of injury to snowboarders (20% of all injuries and 45% of UE injuries). Seventy-eight percent of wrist injuries were fractures, or 35% of UE injuries and 16% of all snowboarding injuries in our study (Figures 10 and Table 3). Eleven percent of these were growth plate injuries. Those in the second decade (10-19) sustained a greater percentage of distal radius fractures and wrist sprains than other age groups as expected by age distribution demographics (49% and 55% vs. 34% respectively). Wrist fractures (except to the scaphoid) and sprains occurred predominantly in beginner snowboarders (Figure 11). In fact, 28% of all injuries in beginners were wrist fractures, but intermediate and advanced riders sustained the majority of scaphoid fractures, and, when we evaluated the patient, generally suffered more severe fractures than beginners.
Almost all (95.6%) wrist injuries were due to a fall. Distal radius fractures and sprains to the wrist were nearly twice as likely to be the result of a backward fall than a forward fall (65% vs. 34%).
There were twelve perilunate or lunate dislocations; an injury caused by extreme hyperextension and violent impact. Outside of snowboarding, these injuries occur primarily from either motor vehicle accidents or falls from heights in excess of 10 feet. Eleven of twelve of the wrist dislocations in our study were sustained by intermediate or expert riders, and all but one occurred in males. Seventy-five percent of the wrist dislocations resulted from a backward fall and all of them involved an aerial maneuver.
Five percent of the snowboarders in the study wore protective wrist splints of some fashion, yet they only sustained 2.4% of the wrist fractures, 3.7% of wrist sprains and none of the wrist dislocations. Use of protective wrist splints, therefore, was associated with a 50% reduction in the expected incidence of wrist injuries, especially fractures (p< .001). It could not be determined if those who used splints and sustained a wrist fracture had different patterns and/or severity of fractures than those who did not wear them. There was greater utilization of protective wrist splints in the latter years of the study (from approximately 2% to 7% of snowboarders).
When use of splints was cross-tabulated to injuries other than to the wrist, there was a higher than expected incidence of humerus fractures, rotator cuff strains, and sprains and fractures to the thumb, but a lower rate of metacarpal fractures, A-C sprain and elbow dislocations. Because of relatively low numbers, however, these findings did not reach statistical significance (Table 4).
The Hand
There were a total of 188 hand injuries in the study or 9.5% of UE injuries; 63% fractures, 32% sprains and 8% dislocations (Table 5). Hand injuries occurred predominantly in intermediate and expert riders (73%), male or female, with almost 50% of the injuries in the expert group (Figure 12).
Injuries to the ulnar collateral ligament (UCL) of the thumb were relatively rare, however (N=41). UCL injuries are the most common UE injury in alpine skiers, comprising as many as 80% of UE injuries [10], but accounted for only 2.4% of UE injuries evaluated and 0.9% of all injuries in the snowboarders in our study (vs. 10-12% of all alpine skiing injuries).
Conclusions and Discussion
Our study produced findings similar to those of other studies [11-16] in that; one and one-half to twice the incidence of UE injuries in snowboarding than in alpine skiing, the wrist was the most common site of injury in snowboarders, the young and beginners were more prone to wrist injury but advanced and male snowboarders sustain more shoulder, hand and elbow injuries, as well as more severe injuries, and fractures and dislocations are more common in snowboarding whereas contusions and sprains are more common in alpine skiing.
A weakness in our study design was that a control group of non-injured snowboarders was not obtained, therefore neither the ratio of snowboarders to alpine skiers nor the snowboarding injury rate could be ascertained. However, the demographics of our injured snowboarder population, in regard to age and gender distributions, were similar to those in the 1995 and 1996 SIA National Snowboarder Surveys of randomly selected, non-injured snowboarders from across the United States (Male/Female ratio 73/27; Average Age=22) [1]. Accordingly, the characteristics of our study population accurately reflected those of US snowboarders in general.
The relatively low incidence of UCL injuries in snowboarders despite the high frequency of falls as mechanism of injury would seem to further indict the ski pole as the main causative factor of the large proportion of UCL injuries in alpine skiers. As with alpine skiers, however, it may be assumed that an unknown number of minor UCL sprains (as well as other injuries) in snowboarders go unreported.
Because of questionnaire design, there was a certain degree of vagueness in diagnosis. For instance, the written diagnosis "distal radius fracture" could include a wide spectrum of injuries from minor, non-displaced fractures, treated with simple immobilization, to severely comminuted and displaced intra-articular fractures requiring open reduction, internal fixation. As a result we were unable to grade and compare severity of some injuries, especially wrist fractures in snowboarders who did or did not wear protective wrist splints.
Furthermore a lift mishap as compared to more advanced ability levels (Table 1). Conversely, 90% of collisions were seen in intermediate and expert riders and 20-29 year-olds. As recognized by other studies [8,9], we did note some specific gender differences (Table 2). Males as a group seemed to ride more aggressively than females at all levels of experience. They were more likely to collide with trees (90% of collisions vs. 10%), injure their shoulders (dislocations, A-C separations and clavicle fractures) and elbows and to sustain more severe injuries than females. Women, on the other hand, sustained more than the expected number of wrist fractures and sprains (38% and 47%vs expected 26%), excluding scaphoid fractures. When gender-related variance in ability level was considered, these differences in injury rates were mostly, but not entirely, eliminated. This was particularly apparent for shoulder injuries in males. The foot that was positioned forward on the snowboard was associated with a slightly higher percentage (56%) of same side UE injuries with some exceptions. Shoulder dislocations, both bone forearm fractures, distal radius fractures and wrist sprains were all twice as likely to occur on the side opposite of the foot forward. There was no correlation between hand dominance and side of injury.
In the light of the relatively high prevalence of wrist injuries in snowboarders, especially in beginners and skeletally immature riders, we strongly advocate the use of protective wrist splints for all snowboarders.
Acknowledgements
We appreciate the work of the allied health staff at Vail • Summit Orthopaedics, but particularly Leslie Ruff, RN. Her dedication and organizational skills were often the engine that kept this study running.
Jan Idzikowski, PA-C is a provider for Vail • Summit Orthopaedics in Frisco, Edwards, and Vail, Colorado.
Paul Abbott, MD is a provider for Vail • Summit Orthopaedics in Frisco, Edwards, and Vail, Colorado.
Peter Janes, MD is a provider for Vail • Summit Orthopaedics in Frisco, Edwards, and Vail, Colorado.
