causes of rib lesions
Fibrous Dysplasia. This painless, typically metadiaphyseal lesion can be monoostotic or polyostotic. When polyostotic, fibrous dysplasia is overwhelmingly (90%) located on one side of the body. The ZOT is narrow and the lesion itself can be quite heterogeneous with a lytic, sclerotic, or mixed appearance (Figure 10). When located in the pelvis, fibrous dysplasia can often appear lytic and bubbly while rib lesions may have a ground-glass appearance and be expansile. Involved tubular bones are expanded and demonstrate cortical thinning.