AOSpine Subaxial Cervical Spine Injury Classification System

The purpose of this project is to describe a morphology-based subaxial cervical traumatic injury classification system. Similar to the effort put toward the thoracolumbar system, the goal was to develop a comprehensive yet simple classification system with high intra and interobserver reliability to be used for clinical and research purposes.Material and Methods A subaxial cervical spine injury classification system was developed using a consensus process. All investigators were required to successfully grade 10 cases to demonstrate comprehension of the system before grading 30 additional cases on two occasions, 1 month apart. Kappa coefficients ( κ) were calculated for interobserver and intraobserver reliability.Results The classification system is based on the following three injury types: compression injuries (A), tension band injuries (B), and translational injuries (C), with additional descriptions for facet injuries, as well as patient-specific modifiers and neurologic status. Interobserver and intraobserver reliability was substantial for all injury subtypes ( κ = 0.64 and 0.75, respectively).Conclusion The AOSpine subaxial cervical spine injury classification system demonstrated substantial reliability in this initial assessment, and could be a valuable tool for patient care and for research purposes.