STUDY OBJECTIVE:In the current era of frequent chest computed tomography (CT) for adult blunt trauma evaluation, many minor injuries are diagnosed, potentially rendering traditional teachings obsolete. We seek to update teachings in regard to thoracic spine fracture by determining how often such fractures are observed on CT only (ie, not visualized on preceding trauma chest radiograph), the admission rate, mortality, and hospital length of stay of thoracic spine fracture patients, and how often thoracic spine fractures are clinically significant. METHODS:This was a preplanned analysis of prospectively collected data from the NEXUS Chest CT study conducted from 2011 to 2014 at 9 Level I trauma centers. The inclusion criteria were older than 14 years, blunt trauma occurring within 6 hours of emergency department (ED) presentation, and chest imaging (radiography, CT, or both) during ED evaluation. RESULTS:Of 11,477 enrolled subjects, 217 (1.9%) had a thoracic spine fracture; 181 of the 198 thoracic spine fracture patients (91.4%) who had both chest radiograph and CT had their thoracic spine fracture observed on CT only. Half of patients (49.8%) had more than 1 level of thoracic spine fracture, with a mean of 2.1 levels (SD 1.6 levels) of thoracic spine involved. Most patients (62%) had associated thoracic injuries. Compared with patients without thoracic spine fracture, those with it had higher admission rates (88.5% versus 47.2%; difference 41.3%; 95% confidence interval 36.3% to 45%), higher mortality (6.3% versus 4.0%; difference 2.3%; 95% confidence interval 0 to 6.7%), and longer length of stay (median 9 versus 6 days; difference 3 days; P<.001). However, thoracic spine fracture patients without other thoracic injury had mortality similar to that of patients without thoracic spine fracture (4.6% versus 4%; difference 0.6%; 95% confidence interval -2.5% to 8.6%). Less than half of thoracic spine fractures (47.4%) were clinically significant: 40.8% of patients received thoracolumbosacral orthosis bracing, 10.9% had surgery, and 3.8% had an associated neurologic deficit. CONCLUSION:Thoracic spine fracture is uncommon. Most thoracic spine fractures are associated with other thoracic injuries, and mortality is more closely related to these other injuries than to the thoracic spine fracture itself. More than half of thoracic spine fractures are clinically insignificant; surgical intervention is uncommon and neurologic injury is rare.