Establishing the Injury Severity of Thoracolumbar Trauma: Confirmation of the Hierarchical Structure of the AOSpine Thoracolumbar Spine Injury Classification System

Study Design. Survey of spine surgeons. Objective. To develop a validated regional and global injury severity scoring system for thoracolumbar trauma. Summary of Background Data. The AOSpine Thoracolumbar Spine Injury Classification System was recently published and combines elements of both the Magerl system and the Thoracolumbar Injury Classification System; however, the injury severity of each fracture has yet to be established. Methods. A survey was sent to 100 AOSpine members from all 6 AO regions of the world (North America, South America, Europe, Africa, Asia, and the Middle East). Each respondent was asked to numerically grade the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System including the morphology, neurological grade, and patient specific modifiers. A grade of zero was considered to be not severe at all, and a grade of 100 was the most severe injury possible. Results. Seventy-four AOSpine surgeons from all 6 AO regions of the world numerically graded the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System to establish the injury severity score. The reported fracture severity increased significantly (P <0.0001) as the subtypes of fracture type A and type B increased, and a significant difference (P <0.0001) in severity was established for burst fractures with involvement of 2 versus 1 endplates. Finally, no regional or experiential difference in severity or classification was identified. Conclusion. Development of a globally applicable injury severity scoring system for thoracolumbar trauma is possible. This study demonstrates no regional or experiential difference in perceived severity or thoracolumbar spine trauma. The AOSpine Thoracolumbar Spine Injury Classification System provides a logical approach to assessing these injuries and enables rational strategies for treatment.