Q. How does a bone scan work?

A. A bone scan can be used to locate a problem area in the spine. A radioactive chemical (sometimes called a tracer) is injected into the bloodstream. Pictures are taken of the skeleton using a special camera that can capture the radiation of the tracer. The image will show dark areas where the chemical tracer has attached to highly active bone. The dark spot is a "hot spot" where bone is changing rapidly, which can happen with problems of overuse, compression fractures, bone tumors, or osteoporosis. After locating a hot spot with the bone scan, your doctor can do other tests to clearly identify the problem area.