Abstract

Background
Rib fractures are the most common injuries resulting from blunt chest trauma. The sensitivity of conventional radiogrphy in showing the rib fracture is limited especially in whom involving the cartilage part of the rib. We investigated the rib fractures, those overlooked on conventional radiography, with the use of ultrasonography in minor blunt chest trauma. Materials and Methods: From september 2002 to March 2004, 40 patients (21 women and 29 men, mean age 43.3±15.1,range 16~85 years), with minor blunt chest trauma showing no evidence of rib fractures on conventional radiography, were admitted for examination with ultrasonography. Logistic regression analysis was done to outlined the clinical predictors of these incidious rib fractures. Results: A total of 15 (35%) patients showed rib lesions, whereas 25 (65%) patients had no evidence of rib lesions. Fractures of rib associated with a periosteal hematoma was the most common finding in ten (66.7%) patients followed by the rib fracture of the rib alone in four (26.7%) patients and subperiosteal hematoma alone in one (6.6%) patient. A total of eight (53.3%) patients had bony rib fractures, whereas seven (46.7%) patients had chondral rib fractures. Age (p=0.280), gender (p=0.431), type of etiology (p=0.823), duration of pain (p=0.470) and site of trauma (p=0.923) did not appear as significant predictors for these rib fractures. However, involved part of the rib showed a significant correlation with either age (p=0.043) or duration of pain (p=0.036). Bony rib fractures significantly occurred in elderly patients, and the duration of pain in patients with bony rib fractures was significantly longer than that of the patients with chondral rib fractures. Conclusions: Ultrasonography is a useful imaging method in showing the rib fractures those overlooked on conventional radiography in minor blunt chest trauma, and no significant clinical feature exists as a predictor for these insidious fractures. However, bony rib fractures significantly occur in elderly patients and result in a longer duration or pain.

• Keywords: Chest trauma, Rib fracture, Ultrasonography