11 ribs demonstrated on frontal CXR

Findings: On this CXR, there are 11 pairs of ribs seen on this frontal view of the chest.

Key Points: If 11 or fewer ribs are seen, there can be an association with a number of congenital abnormalities and certain types of musculoskeletal dysplasias. However, most individuals are completely normal and this is simply an anatomic variant for 10-15% of the individuals found to have this. For instance, <=11 ribs can be associated with trisomy 21 (Down syndrome), trisomy 18, campomelic dysplasia, kyphomelic dysplasias, polydactyly syndromes, spondylocostal dysostosis, spondylometaphyseal dysplasia, and other dysplasias.

Submitted by Dr. Alex Torino to radRounds Radiology Network