Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiomediastinal silhouette and pulmonary vasculature are unremarkable . There is no pneumothorax or pleural effusion . The lungs are clear . A minimally displaced fracture is noted of the posterior left third rib . Nondisplaced fifth and sixth rib fracture may also be present .
    OUTPUT:
    
Rib fractures as described above . No pneumothorax .