To our knowledge, this is the first report investigating the correlation between concomitant pancreatic injuries and severity of trauma to the thoracolumbar spine in a large trauma collective. It can be concluded that concomitant pancreatic injuries are rare, with a prevalence of 0.90% in a group of severely injured patients with trauma of the thoracolumbar spine.
In our collective, middle-aged men in particular presented with an injury to the thoracolumbar spine. Such injuries are also described mainly in men in the literature; however, they were younger on average (8, 9). The average age in our collective is also higher in the group with concomitant pancreatic injury than in the literature (32). The trauma mechanisms that are mainly presented in our analysis coincide with the results of previous studies (5, 6, 8, 9, 32).
The general occurrence of traumatic pancreatic injury in the polytraumatised patient turned out to be rare, with a ratio of 6/1,000 patients in our study collective. This matches the results of the literature (19, 22, 38). However, patients with moderate to severe spinal injuries more often presented an accompanying pancreatic trauma (OR 1.78). It was shown that these concomitant pancreatic injuries occur primarily in spine injuries with a severity of AIS 2 (n = 317; OR 1.93). In our collective, this severity of injury corresponds to a minor vertebral fracture, the dislocation of a facet joint or injury of the nerve root, without involvement of the spinal cord.
There was a decrease in the cases of pancreatic trauma combined with thoracolumbar spine injuries with a severity of AIS ≥3. Although the odds ratio for the occurrence of a pancreatic injury was increased in patients with severe thoracolumbar spinal injuries (AIS 4, OR 1.87; AIS 5, OR 1.99), it should be mentioned that the number of cases was significantly lower (AIS 4, n=8; AIS 5, n=24). Due to the anatomical conditions of the pancreas in the retroperitoneum, a high velocity trauma of the abdomen is necessary to cause a pancreatic trauma (22). This is shown by the fact that patients with pancreatic trauma showed up with more severe injury patterns (mean ISS 35.7) than thoracolumbar injuries without pancreatic trauma (mean ISS 23.8). In the literature, too, patients with traumatic pancreatic injuries were more seriously injured on average (32). In some cases, the main force may be absorbed by the abdomen, so that the spinal injury is less severe than the abdominal; this could be a potential explanation for the decreased probability of concomitant pancreatic trauma between the injury severity groups AIS 2 and AIS 3 (OR 1.93 versus 1.16) in thoracolumbar injuries. This should be examined in future biomechanical studies. The pancreas appears to be at risk of injury due to its location across the thoracolumbar spine and its fixed retroperitoneal location.
Based on our results, there is no direct correlation between the severity of a spinal injury and the occurrence of a concomitant pancreatic trauma. Nevertheless, as mentioned above, there was an accumulation of pancreatic injuries in moderate thoracolumbar injuries. That is why the knowledge of the epidemiology of thoracolumbar spinal injuries and accompanying trauma of surrounding organs is useful and important for assessment, decision making and treatment in patients who have suffered a blunt trauma and are admitted to the emergency room.
Both a pancreatic injury (19, 21, 31, 39) and a thoracolumbar spinal injury can be overlooked clinically. Due to the often delayed or missing diagnosis of a pancreatic injury (24, 25, 32), the reported prevalence may be underestimated in our study as well as in the literature. For this reason, special attention should be paid to the spine and pancreas in the initial diagnostic investigation of a patient who has suffered a blunt abdominal trauma with hyperflexion. A missing diagnosis of a pancreatic injury can lead to complications in the course of treatment (19, 22, 31, 37, 38, 40), as well as long-term consequences like a diabetes (36). This fact was also evident in our study collective with increased complications such as sepsis and MOF in patients with concomitant pancreatic injury. The presence of pancreatic trauma is associated with high rates of morbidity and mortality (22, 32, 38, 41, 42). In our study collective, the in-hospital mortality with accompanying pancreatic injury was also increased, as well as the length of stay on ICU and the length of time in hospital in general. This is due to the increased occurrence of complications and illustrates the clinical relevance of the simultaneous occurrence of a pancreatic injury. In this context, pancreatic injury does not represent an independent risk factor. The effect of a pancreatic injury (adjusted OR 0.88; 95%CI 0.63-1.25) is mostly represented by the Revised Injury Severity Classification II (RISC II), via the AIS of the most severe and second most severe injury.
Diagnostically, a CT scan (21, 23, 26, 28) and laboratory testing (29, 30) of pancreatic amylase and lipase turn out to be important diagnostic tools. However, both can initially be negative (23, 25, 27, 29). Therefore, it is important to remain alert to a combination of thoracolumbar spine and pancreas injuries in order to repeat examinations if an injury is suspected.
Study limitations
Because of a register evaluation this study has some limitations. It contains only retrospective data that were registered in the TR-DGU. If the diagnosis of a pancreatic injury is missing, it is not recorded in the register. The overall prevalence of a pancreatic trauma can, thus, be underestimated.
Epidemiological data, in particular, were presented in this study. The clinical relevance as well as the influence on the outcome has to be evaluated in future clinical prospective studies.