MRI in suspected chest wall fractures: diagnostic value in work-related chest blunt trauma.

Objective: To describe and analyze MRI findings in suspected early fractures of the chest (ribs and sternum) and assess if this technique can add value in occupational medicine.

Materials And Methods: In this retrospective study, we reviewed 112 consecutive patients with work-related mild closed chest trauma who underwent early thoracic MRI, when there was not a clear fracture on radiograph or when the symptoms were intense and not explained by radiographic findings. MRI was evaluated by two experienced radiologists independently. The number and location of fractures and extraosseous findings were recorded. A multivariate analysis was performed to correlate the fracture characteristics and time to RTW (return-to-work). Interobserver agreement and image quality were assessed.

Results: 100 patients (82 men, mean age 46 years, range 22-64 years) were included. MRI revealed thoracic wall injuries in 88%: rib and/or sternal fractures in 86% and muscle contusion in the remaining patients. Most patients had multiple ribs fractured, mostly at the chondrocostal junction (n=38). The interobserver agreement was excellent, with minor discrepancies in the total number of ribs fractured. The mean time to return-to-work was 41 days, with statistically significant correlation with the number of fractures. Time to return-to-work increased in displaced fractures, sternal fractures, extraosseous complications, and with age.

Conclusion: Early MRI after work-related chest trauma identifies the source of pain in most patients, mainly radiographically occult rib fractures. In some cases, MRI may also provide prognostic information about return-to-work.