A recent systematic review that included 17 studies in China showed that the epidemiological features of SCI vary among different regions of China; therefore, targeted prevention interventions should be implemented by region. Further, SCI resulting from falls and MVCs may become a major public health concern as the population ages and the economy continues to develop in China [10]. Compared to other areas of China, northwest China has several unique characteristics. First, it is located in the hinterland of mainland China, which mostly consists of plateaus and basins. Compared with the economically developed eastern coastal areas, the level of economic and political development is low in this region. In addition, northwest China has a landscape dominated by agriculture and farmers account for the majority of the labor force; low levels of health insurance coverage, education, and household income are also observed in this region. As Xi'an is the economic and cultural center of northwest China, the epidemiological characteristics of SCI patients admitted to the tertiary trauma center in Xi’an are representative of those of SCI patients in northwest China. Based on the epidemiological characteristics of SCI over the past 5 years, we found that SCIs not only cause the impairment of sensory and motor functions below the injury level but also cause several debilitating organ dysfunctions, including those of the respiratory, urinary, and digestive systems, which burdens hospitals with additional costs. Hence, SCIs should not be neglected in northwest China. As the prevention of SCIs is particularly important, comprehensive and detailed epidemiological investigation is fundamental for the development of effective prevention countermeasures.
In this investigation, the male to female ratio in SCI patients was 2.57:1, which was different from the ratios reported in Beijing, Shanghai, Guangdong, Chongqing, Anhui, and Heilongjiang [6-9,11,12]. This may be due to the differences in responsibilities and social division of labor between men and women among various provinces of China. Our patients mainly came from the Northwest region, which is economically underdeveloped and resource-poor. The exposure of women to high-risk industries, such as construction and transportation, has been on the rise. Simultaneously, women are prone to osteoporotic fracture, which may result in higher proportions of women among SCI patients; this has been previously observed in South Africa [13].
The highest proportion of SCIs in northwest China was noted among patients aged between 30 and 49 years. In traditional Chinese culture, it is the responsibility of the young and middle-aged individuals to support their parents and raise their children. Thus, due to the large financial responsibility, they take great risks to provide for their families. Additionally, the roads in northwest China are rugged and undeveloped. Hence, these factors increase the possibility that young and middle-aged individuals experience work-related SCIs, rendering the 30–49 years age group a high-risk group. Moreover, as China's aging population is increasing, more elderly people experience SCIs. These patients may have comorbidities such as degenerative spine disease and/or osteoporotic compression fractures. Therefore, the needs of elderly people should be considered in SCI rehabilitation [14]. In our study, the proportions of farmers and workers were as high as 59.51% and 27.04%, respectively. These values are different from those reported in previous studies conducted in the Guangdong region of China [8], Turkey [15], and Mexico [16]. These discrepancies may be a result of the differences in economic and political environments between regions. In northwest China, a high proportion of the population engages in agriculture-related occupations, which are related to a higher probability of SCI occurrence than any other occupation.
The causes of SCIs include falls (high and low falls), MVCs, impact with falling objects, sports, and violence injuries, and these causes vary across countries and regions. An epidemiological survey conducted in Canada in 2006 showed that MVCs were the main cause of SCIs, while falls became the main cause in 2009 [17, 18]. Another study from seven countries in the Middle-East and North Africa (MENA) region found that MVCs are still the leading cause of SCIs, followed by falls, gunshots, violence, and sports [19]. We found that falls (both from a small and large height) and MVCs were the main causes of SCIs and occurred in nearly all age groups. The incidence of violence also varied by country and region, with the incidence of SCI due to violence being as low as 0.40% in Beijing [6] and as high as 28.4% in Brazil [20]. In the same fashion, gunshot wounds were rare in China, mainly due to the strict social security and gun control implemented by the state. As in other developing countries, the per capita car ownership in China is increasing; meanwhile, the improvement in transportation safety measures and the increase in traffic safety awareness have resulted in a decline in traffic-related SCIs.
Similar to the findings of previous studies [9, 21], the analysis of injury locations in this study showed a bimodal distribution, with C4-C6 and T11-L1 being the most common locations of injury. Additionally, we found an association between the severity of SCI and the cause of injury. While injuries resulting from MVCs and falls from a large height mostly lead to complete SCIs, mainly of grade A, falls from a small height primarily cause grade D SCIs (incomplete SCI). Williams et al. [22] and Thietje et al. [23] reported that patients with grade A SCIs are more likely to experience depressive disorders and suicide; therefore, the families and doctors of these patients should provide more care to these patients to help prevent suicide caused by depression.
The results of this study showed that there were 1,341 (36.49%) patients with complications, with respiratory disease being the most common complication (30.7%). Respiratory disease is associated with long-term bed rest, lung disease caused by smoking, and rib fractures. Cervical SCIs may affect the function of the diaphragm or intercostal muscle, weaken respiration, and cause coughing, making it difficult to cough out sputum. Such symptoms may also present as complications related to respiratory disease [24]. The higher is the level of SCI, the higher is the risk of pulmonary infection. The risk of pulmonary infection can reach up to >90% when the SCI occurs above the C5 level, causing dysfunction of the diaphragm [25]. Our results also showed that the average hospitalization duration of SCI patients was 10.70 days, with the longest stay being 94 days, while the hospitalization cost was between 4,352 and 45,6320 yuan (average: 37,850 yuan). It has been highlighted that the hospitalization period of SCI patients is long, the hospitalization cost is high, and the patients have a limited ability to pay for treatment as their income is low; hence, it is difficult to provide comprehensive and effective treatment.
Of all SCI patients, only 15.14% received rehabilitation. Although this may be related to the low overall rate of SCI rehabilitation in northwest China, it reflects the insufficient attention given to SCI postoperative rehabilitation.
The study has several limitations. First, it was a hospital-based descriptive study on SCI that identified only a small proportion of all SCI patients in northwest China. Second, we collected information of patients admitted to the hospital with SCI, leaving out the information on patients who died in hospitals before admission. Third, training on systematic data collection was not provided, resulting in errors in the data collection process.