Disuse osteoporosis: mimic of neoplastic disease.

Disuse osteoporosis, a common sequela to immobilization, consists of bony changes that may mimic neoplastic disease. This paper describes the different types of cortical and medullary demineralization that can be manifested radiologically and the histopathologic basis for these alterations. Six cases are included that exemplify these changes, and comparison is made with multiple myeloma.