302 Rib Fractures in the PanScan Era

Abstract

Rib fractures are the most common thoracic injuries in blunt trauma patients. Fractures of the first and second ribs are traditionally thought to be indicative of significant trauma and are associated with serious injuries, particularly to the great vessels. Increased chest CT utilization in blunt trauma evaluation may diagnose minor, clinically irrelevant fractures. We sought to determine 1) The frequency of rib fracture seen on chest CT only (SOCTO) versus chest x-ray (CXR), 2) The frequency of rib fracture associated great vessel injuries, and 3) Mortality considering patients with rib fracture SOCTO and fractures of the first or second rib. Focusing primarily on patients who had both CXR and chest CT, we conducted a pre-planned analysis of two prospectively enrolled cohorts with the following inclusion criteria: age > 14 years, blunt trauma within 12 hours of ED presentation, and receiving CXR or chest CT during trauma evaluation. We defined rib fractures and other thoracic injuries according to CT reports and followed patients through their hospital course to determine clinical outcomes. Of 21,382 enrolled subjects, 8661 (40.5%) had both CXR and chest CT and 2071 (23.9%) of these had rib fractures, making it the most common thoracic injury. 286 subjects (3.3%) had first or second rib fractures. Rib fractures were SOCTO in 1368 (66.1%). Rib fracture patients had higher admission rates (88.7% versus 45.8%: mean difference 42.9%, 95% confidence interval [CI] 41.4% to 44.4%) and mortality (5.6% versus 2.7%: mean difference 2.9%, 95% CI 1.8% to 4.0%) than patients without rib fractures. Mortality of patients with rib fracture SOCTO was not significantly different than that of patients with fractures also seen on CXR (4.8% versus 5.7%: mean difference 0.9%, 95% CI -2.2 to 4.8%). Great vessel or aortic injury was higher amongst patients with first or second rib fractures (2.8% versus 0.5%: mean difference 2.3%, 95% CI 0.3 to 4.3%). Patients with first or second rib fractures had significantly higher mortality than patients with fractures of ribs 3-12 (7.34% versus 4.18%: mean difference 3.2%, 95% CI 0.2% to 6.97%). Under current blunt trauma imaging protocols that commonly include chest CT, most rib fractures are SOCTO. Patients with rib fractures had higher admission rates and mortality than patients without rib fractures, but there is no difference in mortality of patients with rib fractures SOCTO compared with those whose fractures were seen on CXR. Patients with first or second rib fractures had a higher prevalence of great vessel injury and their mortality was significantly higher.