The utility of bone scans in rheumatology

Purpose: Bone scanning is the most common diagnostic imaging service reques ted by Australian rheumatologists, who order $50,000 (Australian) worth of bone scans annually. Methods: To determine why rheumatologists request bone scans and how they a ffect their patient management, the authors administered a two-part prospec tive survey before and after every bone scan ordered by four rheumatologist s during a 6-month period in 1996. Results: A total of 136 bone scans were requested. The primary indications for scanning were to confirm a clinical diagnosis (38%), to exclude a diagn osis (34%), and to localize the site of pain (17%), The common diseases tha t rheumatologists were attempting to confirm or exclude with bone scanning were inflammatory arthritis, malignancy, and fracture, However, the most co mmon provisional and final diagnosis was soft tissue rheumatism (18%), foll owed by inflammatory arthritis (15%) and osteoarthritis (11%), Bone scans w ere successful in excluding a diagnosis in 87% and confirming a diagnosis i n 80%, In 32%, bone scans altered the clinical diagnosis, and in 43% they c hanged the course of disease management. Bone scan results prevented furthe r investigations in 60%.