Survival among patients with severe high cervical spine injuries - a TraumaRegister DGU® database study

Trauma is a significant cause of death and impairment. The Abbreviated Injury Scale (AIS) differentiates the severity of trauma and is the basis for different trauma scores and prediction models. While the majority of patients do not survive injuries which are coded with an AIS 6, there are several patients with a severe high cervical spinal cord injury that could be discharged from hospital despite the prognosis of trauma scores. We estimate that the trauma scores and prediction models miscalculate these injuries. For this reason, we evaluated these findings in a larger control group.

In a retrospective, multi-centre study, we used the data recorded in the TraumaRegister DGU® (TR-DGU) to select patients with a severe cervical spinal cord injury and an AIS of 3 to 6 between 2002 to 2015. We compared the estimated mortality rate according to the Revised Injury Severity Classification II (RISC II) score against the actual mortality rate for this group.

Six hundred and twelve patients (0.6%) sustained a severe cervical spinal cord injury with an AIS of 6. The mean age was 57.8 ± 21.8 years and 441 (72.3%) were male. 580 (98.6%) suffered a blunt trauma, 301 patients were injured in a car accident and 29 through attempted suicide. Out of the 612 patients, 391 (63.9%) died from their injury and 170 during the first 24 h. The group had a predicted mortality rate of 81.4%, but we observed an actual mortality rate of 63.9%.

An AIS of 6 with a complete cord syndrome above C3 as documented in the TR-DGU is survivable if patients get to the hospital alive, at which point they show a survival rate of more than 35%. Compared to the mortality prognosis based on the RISC II score, they survived much more often than expected.