Epidemiology
Spinal injuries from recreational alpine skiing have been well studied, demonstrating an increasing trend in spinal injury frequency [
9,
10]. Whilst the overall injury rate ranges from 1.5 to 6 per 1000 skier days [
11,
12], the incidence of spinal injuries ranges from 0.001 to 0.01 per 1000 skier days [
13‐
15]. Concurrent spinal injury amongst injured skiers ranges from 1.4–13.4% [
3,
7,
16]. A similar incidence is reported in the paediatric patient population ranging from 7 to 15% [
17,
18]. The mean reported age of skiers who sustained spinal injury, however, ranges from 26.7 to 41 years [
3,
7,
8,
14,
16,
19]. Skiers suffering spinal injuries are predominantly male [
3,
7,
8,
14,
16]. The reason for this predominance remains unclear and requires further elaboration. Of all skiing injuries, about 3% of these can be classified as severe (ISS > 16) [
1]. Amongst severely injured skiers the prevalence of spinal injuries ranges from 35 to 42% [
1,
7,
20]. When the spinal cord is affected, spinal injuries are found to be causal for resultant fatalities [
21].
Mechanism of injury
The commonest mechanism of injury is falling [
4,
5,
14,
16,
17]. Skiers tend to fall forwards leading to cervical spine hyperextension. This might partly explain the increased relative frequency of cervical spine injuries in skiers compared to snowboarders [
22]. Falls involving axial loading most commonly lead to a burst fracture morphology [
9].
Skiing accidents more frequently involved collision than snowboarding accidents [
7,
17,
23], which generally are associated with more severe injury types [
24].
Spinal injury patterns
Whilst trends have been observed, there is no absolute consensus in the literature regarding the typical site of spinal injury in skiing accidents. Retrospective studies included in this study analysed a total of 3309 spinal injuries (Table
1). The lumbar spine represents the most commonly injured site in the majority of these studies (range 30.1–64.8%) [
3,
5,
7,
8,
14,
16,
19].
Table 1
Injury region of spinal injuries in alpine skiers
Tarazi et al. | 1994–1996 | 36 | 30.6 | 27.8 | 38.9 | 0 | 2.8 |
Wasden et al. | 2001–2006 | 1137 | 23.2 | 31.1 | 35.1 | 10.6 | 0 |
Yamakawa et al. | 1988–2000 | 91 | 3.3 | 19.8 | 64.8 | 4.4 | 7.7 |
De Roulet et al. | 2007–2014 | 1353 | 26.6 | 33.7 | 30.1 | 9.6 |
Hubbard et al. | 2000–2008 | 482 | 40.7 | 24.1 | 35.2 | – | – |
Wick et al. | 2000–2011 | 210 | 28.6 | 42.9 | 28.6 | – | – |
Table 2
Injury types in skiers
Gertzbein et al. | 2005–2010 | - 34y | 61 | - | 63.9 | 26.2 | 8.2 | 1.6 | – | – |
Yamakawa et al. | 1988–2000 | 67: 33 26.7y | 91 | fall | 85.7 | 14.3 | 0 | 0 | 12.1 sacrococcygeal 1.1 spinous process 27.5 transv. Proc. 1.1 cervical facet 2.2 odontoid 2.2 tear drop | 9.9 cervical |
Tarazi et al. | 1994–1996 | 70: 30 34.5y | 36 | fall | 40 | 60 | 0 | 0 | 13.9 sacrococcygeal 0 spinous process 11.1 cervical facet 2.8 odontoid 2.8 tear drop | 24 cervical |
In contrast, Hubbard et al. found the cervical spine to be the most commonly affected region [
3]. Cervical spine involvement was reported in 40.7% whilst the lumbar spine accounted for only 35.2% of injuries.
Wick et al. reported fractures of the thoracic spine to be the most frequent [
10]. This finding is reflected in the majority of the literature studied, with thoracic spine involvement being at least the second most common region affected (
R 19.8–31.1%) [
7,
16,
19]. Injuries with thoracic spine involvement tended to be more severe [
8].
Amongst spinal injuries, vertebral body fractures predominate [
14,
16]. Two studies reported these as primarily compression type fractures [
16,
19] (see Table
1). In contrast, Tarazi et al., described compression type fractures in only 40% whilst burst fractures accounted for nearly 60% of the injuries studied [
14]. The more severe distraction type fractures and rotation type fractures were rarely reported [
19].
Table 3
Spinal fracture patterns in snowboarding injuries
Tarazi et al. | 1994–1996 | 27 | 18.5 | 22.2 | 37 | 14.8 | 0 |
Wasden et al. | 2001–2006 | 81 | 17.2 | 29.7 | 42.9 | 9.9 | 0 |
Yamakawa et al. | 1988–2000 | 252 | 2 | 21.8 | 69.4 | 3.2 | 3.6 |
De Roulet et al. | 2007–2014 | 1216 | 23.6 | 33.2 | 34.5 | 8.6 |
Hubbard et al. | 2000–2008 | 113 | 25.3 | 27.1 | 47.6 | – | – |
Masuda et al. | 1997–2009 | 19 | 31.6 | 68.4 | – | – |
Ishimaru et al. | 2005–2012 | 431 | 1.6 | 22.7 | 61 | 4.6 | 7 |
Franz et al. | 2000–2006 | 10 | – | – | 60 | – | – |
Yamakawa et al. reported transverse process fractures in over a quarter of skiing injuries [
16]. By contrast, Tarazi et al. did not describe the occurrence of transverse process fractures but commented on the high incidence of cervical facet fractures [
14].
Spinous process, odontoid peg and tear drop fractures are seldom reported in skiing injuries [
14,
16].
In general, many studies lack systematic fracture classification. Only three studies sufficiently characterised a total of 188 spinal fractures from skiing accidents [
14,
16,
19] (see Table
1).
Table 4
Injury types in snowboarding injuries
Ishimaru et al. | 2005–2012 | 65.7 26.3 | 431 | jump | 82.8 | 14.5 | 2.7 | – | – | |
Gertzbein et al. | 2005–2010 | - 34 | 51 | – | 80.4 | 19.4 | 0 | 0 | – | – |
Masuda et al. | 1997–2009 | 94.7 24.5 | 19b | jump | 0 | 31.6 | 0 | 68.4 | – | 89.5 thoracolumbar |
Yamakawa et al. | 1988–2000 | 68.5 22.3 | 252 | jump | 91 | 9 | 0 | 0 | 6.8 sacrococcygeal 0.8 spinous process 39.9 transverse proc. 0.8 cervical facet 0.8 odontoid 2 tear drop | 6.7 cervical |
Tarazi et al. | 1994–1996 | 100 22.4 | 27 | jump | 36.8 | 63.2 | 0 | 0 | 14.8 sacrococcygeal 7.4 spinous process 3.7 cervical facet 0 odontoid 0 tear drop | 9 cervical |
The incidence of spinal cord injuries (SCI) amongst skiers has increased over the last two decades [
9,
25]. Neurological deficits were most commonly reported in the context of cervical spine fractures [
3,
10,
12,
13,
20,
26]. Hyperflexion of the cervical spine may also lead to isolated spinal cord injury without concomitant fracture or subluxation [
27], especially in pediatric patients e.g. as seen in SCIWORA Syndrome (Spinal Cord Injury Without Radiographic Abnormality). Cervical SCI without skeletal injury was described by Yamakawa et al. in 2.2% of skiers who sustained spinal injuries [
16].
The reported prevalence of neurological deficits with spinal cord injury amongst skiers varied greatly depending on the cohort studied, ranging from 0.93–24% [
3,
9,
14,
16,
19]: Spinal fractures were associated with neurological deficits in roughly a third of the cases analysed by Reid et al. [
9]. Gertzbein et al., who decribed 54 thoracolumbar vertebral fractures from skiing accidents, reported no neurological deficits of any kind [
19].
Again, neurological injury and outcome were not systematically classified according to a recognised scoring system such as the ASIA-Score. As the inclusion criteria were very diverse, comparison of available data is difficult, and neurological impairment stratification in skiing injuries is not possible. Tables
1 and
2 summarize the current data for the region of injury and the pattern of injury in alpine skiing.