Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . There is evidence of mild bibasilar atelectasis . The lungs are otherwise clear without evidence of focal consolidation , effusion or pneumothorax . The heart is mildly enlarged . The mediastinal contours are stable . Mild degenerative changes are seen throughout the spine . No displaced rib fractures identified .
    OUTPUT:
    
No evidence of a displaced rib fracture . If there is further clinical concern for rib fractures , a rib series would be recommended .