Every year about 1,500 new cases of paraplegia are registered in the 21 paraplegia centers in Germany. 1 Of those, more than two-thirds result from accidents. 2,3 According to statistics collected between 1976 and 1996, 8% (n = 22,212) of the registered causes for paraplegia were sport accidents or diving accidents. 2 This article draws from cases from the Orthopedic Department of the University of Heidelberg, and is an analysis of spinal cord injuries caused by sport or diving accidents. The analysis focuses on specific risks of spinal cord injury, the level of the neurologic lesion, age and sex distributions, and the possibilities of injury prevention. Sport and diving accidents are approached separately.
Between January 1985 and January 1997, the Orthopedic Department specializing in the treatment and rehabilitation of paralyzed patients at the University of Heidelberg, Germany, worked with 1,016 cases of traumatic spinal cord injury. All patient records were reviewed for this retrospective study. The following data could be obtained: sport type, cause of injury, level of neurologic lesion, age and sex, and accompanying injuries. Radiologic evidence of spinal injuries was assessed. A comparison was made with former studies (same geographical region in Germany, same duration of observation).
A total of 147 (14.5%) patients had spinal cord injury caused by sport or diving accidents; 78 cases were from diving accidents, and 69 cases were from sport accidents. One hundred thirteen (77%) patients developed tetraplegia, and 34 (23%) patients, paraplegia. One hundred twenty-two were male (83%), 25 were female (17%).
Of the 1,016 traumatic spinal cord injuries we surveyed, 69 were caused by sport accidents. Forty-six patients were male (67%), and 23 (33%) were female. Age ranged from 9 to 52 years, with an average age of 26.8 years.
Thirty-four patients (49%) developed paraplegia; the paralysis was complete in 18 patients (53%) and incomplete in 16 patients (47%). Thirty-five patients (51%) developed tetraplegia; the paralysis was complete in 21 patients and incomplete in 14 patients (Figure 1A).
Sixteen accidents resulted from downhill skiing, and 9 paraplegias resulted from horseback riding accidents. Seven cases of paraplegia occurred while participating in modern air sports such as hang gliding or paragliding. Serious accidents resulting in paraplegia or tetraplegia occurred in gymnastics (n = 6), trampolining (n = 5), competitive motocross (n = 5), cycling (n = 5), soccer (n = 3), toboggan riding (n = 3), scuba diving (n = 2), hiking (n = 2), as well as climbing, wrestling, rugby, high diving, sailing, and water-skiing (1 each) (Table 1).
Most of the sport accidents that resulted in a spinal cord injury occurred from downhill skiing (16 accidents, or 23%). The accident rate in skiing showed 1.5 to 4 accidents per 1,000 skiers;4–6 the incidence of serious spinal injuries among skiers was 0.01 injuries per 1,000 skier-days. 7 Outside causes for injuries included poorly groomed or overcrowded slopes, faulty equipment, and unfavorable weather conditions, approach, and lift transportation. 8 Internal causes for injury included lackadaisical behavior and inattention when skiing and, in many cases, high-speed skiing that resulted in loss of control. 4 Alcohol abuse did not seem to be a major etiological factor in skiing-related injuries. 9
Additionally the injury rate distinctly increased in the afternoon (between 2:00 and 4:00 p.m.) due to fatigue. Seven accidents occurred on prepared slopes, and four accidents on ice or deep snow off the slopes. One patient became paralyzed after a collision with another skier, another patient after a jump. A third patient developed complete paraplegia below T11 after a latent period of 6 hours after a fall. For two other patients, the exact course of events could not be reconstructed. Seven skiers (44%) developed full tetraplegia; 9 skiers (56%) had a thoracic or lumbar spine injury. The skiers were between 10 and 51 years of age. Eleven were male (69%), and 5 were female (31%). Accompanying injuries included five cases of rib fractures, two cases of sternum fractures, and two cases of cerebral concussion.
The Sport Association of Germany (DSB) reports more than 600,000 members currently active in equestrian sports with an increase of about 3% (DSB) per annum. Two-thirds of organized riders are female. 10 When including hobbyists, the risk for injury is quite higher. Equestrian-specific injuries are face–cranium injuries from kicking horses, cranium–encephalon trauma, spinal injuries, pelvis fractures, and fractures of the upper extremities. 11,12 Accidents in horseback riding occur during cross-country rides (50%), sudden stops while riding (25%), and also during exercises performed on horseback (15%). 13 Sixty percent of patients were amateurs who were injured because of mistakes made due to inexperience. 14
Nine patients (13%) developed a spinal cord injury after a riding accident. Eight of the injured were female. Five patients had injuries of the cervical portion of the spinal cord, which developed into incomplete tetraplegia, four cases developed into paraplegia, and one into an incomplete paralysis below L3. Three horsewomen fell together with their horses while jumping over hurdles and suffered dislocations–fractures of the cervical spine. The other injuries happened during cross-country rides; four injuries were caused by the horse stopping abruptly and riders falling head over heels onto hard ground. The riders were between 12 and 42 years old. The distribution scheme of paralysis shows that the location mostly affected is the cervical spine. Fractures in the thoracic and lumbar regions are rare. Accompanying injuries included two cases of rib fractures and two cases of cerebral concussion, respectively, with contusion.
Especially in the southern part of Germany, modern air sports such as hang gliding and paragliding have become more popular in the last few years. The most dangerous phase in this sport is in landing, which bears a high risk of injury to the spine and spinal cord. Serious injuries during take-off and flight are more rare. 15 Several reasons for collisions are faulty equipment, false starts, changing weather conditions, mistakes due to inexperience, and collisions with power lines, which can lead to serious burns. The number of people becoming paralyzed from this type of sport is increasing. Statistics show that the risk of injury climaxes between the 5th and 20th flight. 15,16 Among parachutists, the injury rate in the last 10 years has not changed. 17
Burst or luxation fractures from hang gliding or paragliding occurred in three and four cases, respectively. All of the injured were men between 22 and 46 years. Each case included damage of the thoracic or lumbar spine. Two patients developed complete paraplegia, the others incomplete paralysis. Damage of the cervical spine did not occur. One patient collided with a tree. All but one patient crashed during landing from different heights (3–20 meters). Accompanying injuries for crashes from a height of more than 15 meters were fractures of the lower extremities and the pelvis.
Trampolining and Gymnastics
Trampolining and gymnastic injuries occurred mainly in children and teenagers. Children up to age 18 years make up the second highest group in the Gymnastic Association of Germany. In most cases, injury was caused by hyperflexion (salto) or sprain. 18 The survey included five injured due to trampolining and six due to gymnastics. The patients were between 9 and 35 years of age. In seven cases the injured were younger than 20 years. The oldest one fell from a high horizontal bar. Six injured were female, five were male. All patients suffered a lesion of the cervical spine followed by tetraplegia, and in four cases by an incomplete paralysis. There were no accompanying injuries.
Since trampolining has been excluded from school sports in the past few years, the number of injuries is likely to decrease in the future. The last accident from trampolining treated at our hospital was in 1987.
Motocross and cycling are sports that do have serious accidents during training and competition. For five motocross riders the accident happened while jumping the motorbike. Four suffered paraplegia, and one, an incomplete tetraplegia below C3. All patients were males between 19 and 52 years of age. On account of the high speed at which the accidents occurred, there were accompanying injuries such as rib fractures and fractures of the upper extremities.
In cycling, more accidents occurred toward the end of races because of obstructions or mass collisions, bad roads, faulty equipment, and collisions with cars. The upper extremities were mostly affected (about 40%). Injuries of the trunk counted for only 10% of cases. 19 Five cyclists fell at high speeds while rounding curves. Three suffered injury of the thoracic cord followed by paraplegia (one incomplete). One cyclist suffered a luxation fracture at C5/6 with incomplete tetraplegia below C5, and another, a spinal contusion with incomplete tetraplegia below C6.
Three accidents in soccer led to spinal cord injury. The trunk was affected in 12% of the injuries. The main injuries were those of the lower extremities at a rate of 69%. 20 Two collisions with other players led to luxations at the middle of the cervical spine. One case developed complete tetraplegia below C5, another an incomplete tetraplegia below C4. Another player became entangled in the net and struck his head on the goal post. He suffered a discoligamental rupture between C2 and C4 followed by complete tetraplegia below C4.
Three accidents happened in toboggan riding (age 42, female, L1 incomplete; age 35, male, C5 incomplete; age 33, male, T6 incomplete). Two accidents happened in scuba diving during decompression, followed by an incomplete paraplegia in the middle of the thoracic spine (ages 31 and 51; both male). Hiking and climbing left one woman with complete tetraplegia and one with incomplete paraplegia (ages 25 and 31; both female). A 16-year-old boy fell 7 meters and suffered a luxation fracture in the middle of the thoracic spine followed by complete paraplegia below T10. Other accidents happened in rugby (age 19, male, C5 complete), wrestling (age 20, male, C8 complete), high diving (age 18, male, C6 complete), sailing (age 43, female, C5 incomplete), and water-skiing (age 17, male, T11 complete).
Between January 1985 and January 1997, the Orthopedic Department treated 78 patients who suffered paralysis from diving accidents. The age range was 11 to 37 years, with an average of 20 years. Seventy-six patients were male (97%). All of the injured developed tetraplegia, of which 34 were incomplete (Figure 1B). In most cases the injury resulted from diving head first into unknown waters or shallow areas at public pools. An important factor accompanying accidents in artificial lakes and low-depth rivers was often alcohol. 21 Head-first impacts led to hyperflexion, hyperextension, or compression fractures in the cervical spine. These types of accidents were often followed by amnesia, which made it difficult to reconstruct the exact course of events.
Sport accidents can lead to grave and permanent injury and/or death. 19,22–28 The steadily rising number of traumatic spinal cord injuries from sport and diving accidents gave rise to a sport-specific analysis of our patients from January 1985 to January 1997. An analysis of the accidents was carried out to design preventive measures.
Research by Steinbrück and Paeslack showed that 8.4% of the paralyses treated between 1967 and 1977 (n = 2,346) were from sport or diving accidents. 29,30 At the Werner-Wicker Hospital at Bad Wildungen, between August 1978 and July 1987, 654 patients with traumatic spinal cord injury were treated; 11% had sport or diving accidents. According to research by Zäch 31 and Meinecke 32 sport and diving accidents made up 10–13% of paraplegia cases.
An analysis of accidents that resulted in damage to the spinal cord shows that sports that have become popular within the last 10 years have produced an increasing risk of injury. Modern air sports, such as hang gliding and paragliding, cause the most injuries. In most cases, accidents occurred because of insufficient instruction and overestimation of the ability of the participants.
In our research most of the accidents followed by paraplegia or tetraplegia happened in skiing. Simple falls at high speed caused the most injury. 10 The most severe, sometimes fatal, accidents were caused by collisions with immovable objects such as trees or lift towers. 33 Men were greater risk takers than women. 4,7
In skiing, preventive measures such as staying within one's own abilities and adhering to warnings not to ski away from prepared slopes should be taken to prevent injury. Skiers should stop skiing once fatigue sets in, preferably before. All obstacles should be carefully marked, and intensive training should be given by instructors or associations. Uphill lift capacity should be limited to reduce overcrowding. Categorizing and flagging of ski slopes should help to prevent high-speed collisions. 34 There should be warnings about skiing while inebriated. 35
The frequency of head and spine injuries in skiing has not changed over the past 25 years. 5 Improvements or alterations in equipment and slope maintenance seem to have little effect. To minimize risk, every skier should participate in strength and endurance training, especially for the legs and back. 4
Fortunately, our research showed that the last accident from trampolining was in 1987. Most of the injured were young women. The removal of trampolining from school sport programs in different regions of Germany led to a definite decrease in spinal cord injuries from this type of sport. The proportional share of paralyses from gymnastics has also slightly decreased. An important preventive measure is good training for beginners. 36
Spinal cord injuries from horseback riding accidents have remained steady. A reduction in the severity of head injuries was associated with an increased use of riding helmets. 11 Women, who make up the majority of riders in this sport, may become seriously injured 11,16 because of poor concentration, insufficient instruction, or a fall from a horse. Awareness, competent instruction, and proper equipment such as intact bridles, unbreakable helmets, and releasable stirrups should be obligatory. Improvements in training and protective riding gear were associated with a decrease in the total number of riding injuries. 11
Sports such as motocross or cycling, which are practiced at high speeds, bear a high injury risk. Motorcyclists sustain more severe injuries to all parts of the body, whereas pedal cyclists have less serious whole-body injuries and more head injuries. 37,38 A lack of conditioning and technique, bicycle malfunction, poor road surface, and inappropriate behavior while cycling can lead to a loss of control and to severe injury. 38 Wearing a helmet and responsible cycling can reduce injury. Helmet use alone has been proven to reduce the risk of head and brain injuries. 39 However, prevention of serious bicycle injuries cannot be accomplished through helmet use alone. The risk of neck injury is increased by collisions with a motor vehicle. 40 To our knowledge, studies of spinal injury reduction when wearing protective gear have not been reported.
Soccer, rugby, and other competitive contact sports can also lead to serious injury of the vertebral column, although they are less frequent. In soccer, poor field condition was also found to be a factor predisposing to injury. 41 Closer supervision by officials in the area around the goal should reduce the risk of injury to goalkeepers. 42 Intense training in technique and coordination can reduce the injury risk. 20 Numerous studies have shown increased prevalence of acute cervical lesions in front-line rugby players. 43 Use of headgear is recommended for protection from lacerations and abrasions and to provide some protection from impact injury. 44 The effectiveness of helmets in preventing injury to the neck is questioned because cervical vertebrae cannot be protected from compression. 43
The incidence of accidents in traditional rock climbing is 2–4 injuries per 1,000 climber-days. About 0.5–1 injuries in 10,000 climber-days was a fatal injury. 45 The main causes for accidents are insufficient equipment as well as carelessness, overestimation of ability, and lack of conditioning. Awareness of the degree of difficulty for a climb, and undergoing intense technical training can help prevent injury. 46 Climbing should be limited to correspond with the climber's skill and experience levels; major climbing workouts should be followed by rest and/or mild activity for 48 hours. 45
A comparison with studies from other countries showed that there are regional differences. In the United States, 7.3% of spinal cord injuries are caused by sport accidents. 47 In France, 42% of 73 reported sport accidents resulted in spinal injuries from diving accidents. 23 Research in Japan showed that the majority of injuries were a result of gymnastics and diving accidents. 48 Also, diving was the most common cause of spinal cord injury (21.6%) in a nationwide epidemiological survey on spinal cord injury in Japan. 49 A study by Ohry and Rozin reported primarily on air sport accidents in Israel. 50 Analyses in Australia, Arkansas, and South Africa stated that most of the spinal cord injuries resulted from rugby or football accidents. 22,51,52 Turkey had the highest number of spinal cord injuries in general from falls and gunshot wounds. 24,53
In Germany, 4–5% of the causes for traumatic spinal cord injury were diving accidents. 54 Diving-related injuries ranged from 2.3% of spinal cord injuries in a South African study to 21% of spinal cord injuries in Poland. Boys were more frequently injured; the highest incidence occurred among children ages 10 to 14, where few were older than 25 years. 21 Warnings about mixing alcohol and sports do not influence many sports participants. 55 In diving, safety practices such as stirring up the water surface and protecting the head with the arms are recommended. In Australia, a prevention program that included installing warning signs, airing commercials on TV, and putting up posters helped to decrease the high number of accidents resulting in spinal cord injury. 56 Also, in Germany (TV commercials) and the United States (Think First Campaign), various ideas have attempted to reduce the incidence of cervical injuries.
The preventive interventions suggested above can reduce injuries in general, but in most sport disciplines there is no evidence that the same measures can reduce spinal injuries. Only in trampolining (removal from school programs) or diving (prevention programs), can spinal injuries be reduced. 56
Although most men and women start their sport training as youngsters or young adults, they hold a major risk of becoming injured. Highly trained sport instructors should educate students about the risks and dangers of their sports. Only intensive education and training can help to reduce the risk of serious injury. Further studies are required to show any evidence of preventative interventions.
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