A bone scan is used to evaluate damage to the bones or to monitor conditions that affect the bones, such as trauma and infection. Bone scans can often detect problems well in advance of regular X-ray scans.
In a bone scan, a radioactive tracer is injected into the arm. The tracer travels through the bloodstream and into the bones. A special camera takes pictures to show cell activity and function in the bones. Areas that absorb little or no amount of tracer appear as dark or “cold” spots, which might indicate a lack of blood supply to the bone or the presence of certain types of cancer. Areas of rapid bone growth absorb increased amounts of the tracer and show up as bright spots in the pictures, possibly indicating the presence of a tumor, a fracture or an infection.
Bone scans are prescribed to:
- Determine whether cancer from another area has spread to the bone
- Help determine the cause or location of unexplained bone pain, such as chronic lower back pain
- Identify arthritis or osteoporosis
- Diagnose broken bones, such as a hip fracture or stress fracture
- Detect damage to the bones caused by infection or other conditions
The radioactivity of the tracer used in a bone scan is very low, and there are no side effects. The scan takes approximately one hour to complete.