Imaging Paget's disease of bone--from head to toe.

Paget's disease of the bone is a common, non-inflammatory, metabolic, skeletal disorder of unknown aetiology characterized by an increase in osteoclast-mediated bone resorption and compensatory excessive osteoblast activation. Prevalence increases with age, and a pronounced geographical variation is well documented. The disease is often an incidental finding on a radiological examination requested for an unrelated indication. The osteolytic, mixed osteolytic/osteoblastic, and osteosclerotic phases may occur in the same patient and same bone in a synchronous or metachronous fashion. Radiological features in each phase mirror the histopathological appearances, and are distinctive enough to establish a diagnosis with confidence. Using multi-technique imaging, this review illustrates the most common and the not so common radiological patterns of involvement in Paget's disease of bone observed at our centre during the past 20 years.