Q. How does a bone scan work?

A. Bone scans are used to locate problem areas in your spine. A radioactive chemical (sometimes called a tracer) is injected into your bloodstream. Pictures are then taken of your skeleton using a special camera that can capture the radiation of the tracer. The image will show dark areas where there is highly active bone. The dark spot is a "hot spot" where bone is changing rapidly, perhaps because of overuse, a compression fracture, a bone tumor, or osteoporosis. After locating a hot spot with the bone scan, your doctor can do other tests to make a final diagnosis.