Radiographic Predictors of Spinal Column Instability after Gunshot Wounds: A Pragmatic Score

Background Firearm injuries to the spinal column remain a major United States public health concern and present an uncertain challenge in assessing spinal stability. No scoring system currently exists to evaluate ballistic injuries to the spinal column. We propose the BaLlistic Assessment in Spine Trauma (BLAST) score to differentiate stable and unstable ballistic spine fractures for the purposes of operative stabilization. Methods Over approximately 14 years, the University of Mississippi Medical Center neurosurgical service evaluated 353 gunshot wounds (GSW) to the spine. Patients who presented with radiographic injury to the spinal column were included and then evaluated with the BLAST score in this retrospective chart review study. Results Our results indicate that a score of 6 or more correlates with operative management. As a test, the BLAST score ultimately performed commensurate with the accuracy reported in validation studies of the Subaxial Cervical Spine Injury Classification System (SLICS), Thoracolumbar Injury Classification and Severity Scale (TLICS), and Spinal Instability Neoplastic Scale (SINS) scoring systems, achieving a receiver-operating characteristic (ROC) area under the curve (AUC) of 0.965 and 0.812 for cervical and thoracolumbar injuries, respectively. The BLAST scoring system achieved kappa statistics of 0.39 and 0.40 and intraclass correlation coefficients (ICC) of 0.82 and 0.79 for the cervical and thoracolumbar spine, respectively. Conclusion The BLAST score offers an efficient, accurate, and pragmatic composite score than can differentiate stable and unstable injuries in GSW to the spine.