Normal bone scan results show radioactive tracer that moves evenly through all bones, and abnormal results show hot or cold spots, says MedlinePlus. Hot spots indicate areas that have taken up more tracer, and cold spots show areas that have taken up less. Results must be compared with other images.
Bone cells congregate in areas that need repair, and during a bone scan, the radioactive tracer follows these cells and shows up on images taken by a special camera, says Healthline. Although a bone scan detects issues in bone metabolism, it may not reveal the reason for them. When a bone scan shows abnormalities, further tests may be required to pinpoint their cause.
Doctors use bone scans to track and diagnose different types of bone disease, explains Mayo Clinic. The scan senses changes in bone metabolism, and it is used to diagnose several different kinds of disorders, including cancer that has spread from other locations in the body.
Some fractures cannot be seen on an X-ray, but a bone scan can diagnose these, notes MedlinePlus. Scans are used on patients with unexplained bone pain. Several different metabolic disorders, such as osteoporosis and Paget's disease, are diagnosed with bone scans. Bone infections such as osteomyelitis are also diagnosed with bone scans.