Diagnostic accuracy of thoracic ultrasound and chest radiography for detection of traumatic rib fractures using computed tomography as the reference standard

Abstract Background This study was done to compare the diagnostic accuracy of thoracic ultrasound (US) and plain chest X-ray in detecting traumatic rib fractures, using computed tomography (CT) as the reference standard. Methods This diagnostic accuracy study with multiple reads included 30 adult patients with clinically suspected rib fractures, collected during a period of 5 months. All patients underwent chest X-ray, thoracic US, and CT within a defined time interval (within 3 h, 15 h, and 22 h from the time of admission, respectively). The number, side, and rib level of fractures were recorded for each modality. All thoracic ultrasound studies were performed a single experienced operator. Results CT detected the highest mean number of fractures (5 ± 4.1), followed closely by US (4.5 ± 3.9), while chest X-ray detected significantly fewer fractures (1.6 ± 1.7) ( P < 0.001). US demonstrated very strong correlation with CT ( r = 0.984, P < 0.001) and excellent agreement (ICC = 0.994), whereas chest X-ray showed only moderate agreement (ICC = 0.601). US achieved high sensitivity (91.3%), specificity (100%), and overall accuracy (98.2%), with strong composite indices (F1-score 95.4%, MCC 94.5%). In contrast, chest X-ray showed a lower sensitivity (32.9%), accuracy (86.1%), despite perfect specificity (100%). Conclusion Thoracic US is a highly accurate, reliable, and radiation-free modality for detecting traumatic rib fractures and closely approximates CT in estimating fracture burden. It significantly outperforms plain chest X-ray and may serve as a strong imaging tool in hemodynamically stable patients. Larger multicenter studies are recommended to further validate these findings and assess their impact on clinical outcomes.