Monostostic fibrous dysplasia with nonspecific cystic degeneration: A case report and review of literature.

Fibrous dysplasia (FD) has been regarded as a developmental skeletal disorder characterized by replacement of normal bone with benign cellular fibrous connective tissue. It has now become evident that FD is a genetic disease caused by somatic activating mutation of the Gsα subunit of G protein-coupled receptor. Here we report a case of bilateral monostotic FD in a middle-aged female showing a classic histological picture, but radiologically presenting as a mixed radiolucent radiopaque lesion showing nonspecific cystic degeneration.