Upgrading a Classic - Bone Scans in Rheumatology

Bone scanning is one of the most common procedures performed in the majority of nuclear medicine departments. Radionuclides on 99m-Tc phosphonates initiated the widespread use of bone scintigraphy over 40 years ago. These diagnostic methods exhibit excellent sensitivity in the detection of local abnormalities of bone metabolism, but specificity is lacking. Interpretation using conventional radiological diagnostic methods coupled with a focus on the patients´ history and clinical signs are essential. Bone scintigraphy makes valuable contributions to orthopedics and traumatology; in cancer patients the method is used to detect bone metastasis and target areas for radionuclide therapy in controlling severe osseous pain in both cancer and polyarthritis patients. The development of inflammation scan methods, such as the antibody-labeled granulocyte scan and introduction of methods to detect chronic infectious processes by 67-Ga amplified the diagnostic accuracy. Nuclear medicine today has a broad program for diagnostic and therapeutic approaches to diseases of bone and joints. In a vast spectrum of rheumatological diseases, these methods contribute to early diagnosis, interpretation of extension and are used during follow- up to define both the inflammatory activity in arthritic joints and the therapeutic response in osteoarthritis. Recently the use of 18-FDG by PET camera systems to detect malignancy and infection has provided additional information in the management of rheumatology patients - especially considering differential diagnosis in metastatic diseases. In the future, the excellent properties of 18-F in bone metabolism indices for skeletal PETs may lead to its broader use not only in Paget's disease or SAPHO syndrome, but also in osteoarthritis and the management of patients with osteoporosis.