TSCI imposes a substantial burden on individuals, their families, and society because of the cost of health care treatments, rehabilitation, and lost productivity. To our knowledge, the current study is the first hospital-based retrospective study on TSCI in Shaanxi Province. We conducted this study to add the information about the demographics and epidemiological characteristics of patients with TSCI in Shaanxi for the optimal allocation of medical resources and to provide improved medical services to patients with TSCI.
We found that the average age of Shaanxi TSCI patients (48.4±14·9) was higher than the global average age of TSCI (33 years), which was also higher than the average age of Chinese TSCI patients reported in the previous review. Previous studies have shown that the age of patients with TSCI has a bimodal distribution[9–11], and this study had a unimodal distribution for age. Most of the injuries were in the 46-55 age group (25.6%), followed by the 36-45 age group (20.5%), which shows that adults are still the main population that have TSCI. We also found that men in Shaanxi have a higher risk of suffering from TSCI than women (3.45:1). which is in accordance with a previous study on TSCI conducted in Chongqing. According to other countries' data, for patients with TSCI, the ratio of male to female was 2.3-2.8:1 in the United States from 1993-2012; in Australia from 2002-2012 was approximately 1.5-2.4:1. The main reason is that most women are housewives with low-risk occupations, but men are more likely to engage in high-risk work outdoors[9, 10]. The imbalance between men and women in China may be one of the factors that make their male-female ratio slightly higher than other countries.
Moreover, this study revealed that the main etiologies of TSCI in Shaanxi included high falls (40.2%), low falls (26.7%), traffic accidents (22.8%), Compared with those of a 2011 report from Tianjin and a 2017 report from Guangdong , we all sure high falls was leading cause in most city of China. High falls mainly occurred in construction sites, and the Chinese government has increased economic support to the North Western region in recent years and vigorously developed infrastructure construction. The construction unit needs to strengthen the individual's awareness of safety and security, focus on monitoring the safety and quality of production, and provide a safe working environment. Low falls as a second cause in Shaanxi and a tendency increase with increased age means low-energy injuries mainly occurred in the elderly, therefor, falls prevention of older people needs more attention than other risk factors. Especially, we found that the main cause of cervical spinal cord injury was low falls (36.4%).
The most common level of injury observed in the current study was cervical injuries, which accounted for 48.7% of the total cases, which is in accordance with a previous study[9, 14, 15]. However, for the first time, we found that the proportion of cervical SCI increased significantly with age. The possible reason for the analysis is that the degeneration and hyperplasia of the cervical vertebrae are obvious with the increase in age. The cervical spinal canal stenosis is caused by the disc herniation and ossification of the ligamentum flavum, and the volume of the spinal canal for compensation is significantly reduced during the trauma; thus, even low-energy trauma, such as a low fall, can easily cause damage to the spinal cord. We also found that the proportion of low falls continues to increase with age.
Regarding the severity of the injuries, we used ASIA grade to quantify it. ASIA D (37.8%) still is the main grade, followed by ASIA A (26.8%). We found that the most important ASIA grade of patients with cervical SCI is grade D, while the most important ASIA grade of patients with thoracic spinal cord injury is Grade A. This may be because the majority of elderly patients who with cervical SCI suffer from low-energy injury such as low falls. However, the thoracic spine and ribs constitute the thorax with good stability, usually in the condition of high-energy injury can cause thoracic spinal cord injury, and the severity of injury is often more serious.
TSCI with spinal fracture is more common. C5 and C6 vertebrae were more common in cervical spinal fracture, and L1 and L2 vertebrae are more common in lumbar spinal fracture, showing a bimodal distribution. This finding is consistent with previous research conclusions[12, 16], but we further studied the types of fractures and found that the most common fracture form of C5 and C6 vertebrae was dislocation, and the fracture types of T12 vertebrae and L1 and L2 vertebrae were mainly burst fractures. We first found that the proportion of TSCI with cervical spine fractures increased with age, and the proportion of lumbar fractures decreased with increasing age. This may be because with the increase in age, people's bones are gradually becoming looser, and they are slow-moving, have decreased vision, slow protective emission, etc., which makes it easier to fall. A large number of studies have confirmed that low falls are the most common cause of cervical fractures in elderly patients[17, 18], and the rising proportion of falls we found that cause injury with age better explains the above situation. Previous studies have confirmed that elderly fractures mainly occur in the thoracolumbar region, mostly due to osteoporosis combined with low-energy injury. The type of injury is mainly compression and rarely causes damage to the thoracolumbar spinal cord. Therefore, burst fractures of the thoracolumbar spine caused by high energy damage are relatively rare in elderly patients.
In this study, multiple injuries were more common in the chest, but previous research has shown that the main multiple injury is a head injury, and the main cause of injury is traffic accidents[11, 20]. Our research also found that traffic accidents and high falls are most likely to cause chest injuries, and low falls are most likely to be combined with head injuries. The current results demonstrated that 27.8% (193 cases) of patients with TSCI experienced clinical complications, and the three main complications were respiratory system (51.3%), electrolyte disorder (25.9%) and venous thrombosis (21.8%). Respiratory complications such as pulmonary infections are the most common complication of TSCI. This finding has become a common consensus.
We found that 76.4% of patients underwent surgical treatment. The mainstream surgical approach is decompression, fixation and bone graft fusion. The posterior approach is more common. Patients with incomplete SCI were more likely to receive rehabilitation treatment than patients with complete SCI (P <0.5). Less than half of the TSCI patients (46.5%) received rehabilitation, the following possible reasons were summarized: 1. Medical resources for post-traumatic rehabilitation in Xi'an are still relatively scarce, and only some large trauma centers have rehabilitation departments. 2. The concept of rehabilitation is relatively backward, still dominated by the concept of rehabilitation of traditional Chinese medicine, with little effect. 3. The surgical treatment of spinal cord injury is expensive, and the heavy economic burden makes patients have to give up rehabilitation treatment. There was no statistical difference in the length of hospital stay and the proportion of surgery between two groups.
In all of the patients included in this study, only 7 patients (1.0%) had in-hospital deaths, which was significantly lower than the US-reported average in-hospital mortality rate of 7.5% in 2010-2012. We conclude that the death data of this study are heavily influenced by traditional Chinese concepts. For example, for patients with severe TSCI who need to be maintained by a ventilator, family members who choose to give up treatment due to economic burden will maintain the patient's vital signs until they return home. Outcomes about the main causes of death, main causes of injury, and major injury levels for in-hospital died patients were the same as in previous studies[20–22].
There are some limitations in this study. The data are retrospective. Therefore, it is inevitable that there will be wrong information in the original case record, which will lead to deviation. We lost some information because many complications and treatments were not fully diagnosed or recorded in the medical records. This study was a hospital-based descriptive study about TSCI, which identified only a small part of all patients with TSCI in Shaanxi; thus, the overall incidence rate could not be calculated. In addition, the data of this study are limited, and the annual count of TSCI patients is not clear.