FINDINGS:
There is trauma board artifact overlying both lungs.  Mild prominence of the
 cardiac silhouette is likely accentuated by supine positioning and AP
 technique.  The cardiomediastinal silhouette is otherwise within normal
 limits.  Minimal density at both lung apices is noted, but the appearance is
 not  typical for apical capping.  Lungs are relatively well expanded.  No CHF,
 focal infiltrate or consolidation, or pleural effusion is identified.  No
 supine film evidence of pneumothorax is detected.
 
 Limited assessment of the upper abdomen is grossly unremarkable.  Visualized
 osseous structures are notable for mild degenerative changes within the
 thoracolumbar spine, with osteophyte formation and subchondral sclerosis. 
 There is a possible nondisplaced posterior  left rib fracture.

IMPRESSION:
1.  Possible non displaced posterior left 11th rib fracture.  Clinical
 correlation for focal tenderness in this location is recommended.
 2.  Otherwise no acute pulmonary process identified.
 3.  Mild prominence of the cardiomediastinal silhouette is likely accentuated
 by technique.  Attention to this on followup radiographs could help for
 further assessment.