Diagnostic Accuracy of Bone Scan Compared to Computed Tomography of Thorax Fractures of Chest Trauma Patients

ABSTRACT

PURPOSE: Thorax computed tomography (CT) is the diagnostic test for chest trauma patients in the emergency department. Thorax CT has high diagnostic accuracy for rib, sternum fractures. However, rib, sternum fractures are often missed by thorax CT. In this study, the accuracy of thorax CT as a diagnostic test of rib, sternum fractures was examined by comparing the diagnosis of rib, sternum fractures by bone scan. METHODS: A total of 112 patients who had visited the emergency department due to chest trauma and who had undergone both thorax CT and bone scan from January 1, 2010, to June, 30, 2013 were examined. We examined the patients'characteristics, vital signs and cause of trauma through a retrospective analysis of medical records, and thorax CT and bone scan were read by a radiologist and a nuclear medicine specialist. RESULTS: Among 112 patients, 62 patients (55.3%) were male, 50 patients (44.7%) were female, and mean age was 56. There were 59 patients who had no fracture on thorax CT and were regarded as contusion. In 59 patients, 28 patients (47.5%) were diagnosis rib, sternum fractures detected by bone scan. Sex (p=0.188), age (p=0.624), and cause of trauma (p=0.389) were not significant predictors for rib, sternum fractures. However, combined fracture (p=0.043) showed significant correlation. In this study, the sensitivity, specificity, positive predictive value, and negative predictive value of thorax CT in diagnosis of rib, sternum fractures were 64.5%, 93.9%, 96.2%, and 52.5%. CONCLUSION: Thorax CT has low sensitivity (64.5%) and low negative predictive value (52.5%) in detection of rib, sternum fractures. Although thorax CT shows no thorax fracture, when patients have persistent pain or they need accurate diagnosis, we may recommend bone scan for detection of rib, sternum fractures and accurate diagnosis.