A Patient's Guide to Bone Scans
What it is: A bone scan can be used to locate a problem area of the spine. It is a test where a radioactive chemical is injected into the bloodstream and pictures are taken a short time later. The chemical very quickly attaches itself to areas of the skeleton that are busy making new bone. In an adult, this usually means there is a problem in the area and the increased bone making activity is a response by the skeleton to a problem in the area.
For example, if there is a fracture of the bone, the bone cells will very quickly begin to make new bone to try to repair the fracture. The injected chemical begins to concentrate in this area several hours after the injection. A special camera takes pictures of the area of the skeleton where the problem is. Problem areas will show up as dark areas on the film, because more of the chemical has concentrated in that area. Since the chemical tracer is radioactive, it sends out radiation that can be captured by a special camera. The camera is similar to a "Geiger counter" in that it uses film to capture the radioactivity. The radioactivity shows up as a hotspot on the film.
What the test shows: A bone scan is very useful when it is unclear exactly where the problem is in the skeleton. It offers the ability to take a picture of the entire skeleton and light up the area where the problem seems to be coming from. This gives the doctor the advantage of pinpointing exactly where to look next. After locating the problem areas, other tests will be done to show more aspects of those specific spots. The bone scan can show problem areas such as bone tumors, infection, and fractures of the spine. A bone scan can also be used to determine bone density and the bone-thinning condition of osteoporosis.
What the test does not show: The bone scan does not show the details of the bones or soft tissue. It only shows how much the bone around a specific area is reacting to the problem.
How the test is done: The bone scan works by injecting a radioactive chemical, sometimes called a "tracer", into the bloodstream through an intravenous line (IV). The chemical will attach itself to any areas of bone that are undergoing rapid changes. The test requires that an IV be started in your hand or arm. The chemical is then injected and you wait for several hours. Usually you are free to leave and come back in two to three hours. You will then be asked to lie or sit underneath a large "camera" that will take pictures of the skeleton. This may take 30 - 90 minutes.
What risks the test has: The test uses a dye that must be injected. There is always the risk of an allergic reaction to anything injected into the bloodstream. In this case, an allergic reaction is uncommon. The dye that is injected is a radioactive substance, however, it disappears from the body very rapidly (within hours).
What the test costs: A bone scan of the spine usually has two costs associated with it. The first cost is the fee for actually doing the test. This is called the "technical fee". The second cost is the fee of having a specialist, such as a radiologist, read and interpret the test. This is called the "professional fee". You may get two bills for this test: one from the hospital or clinic where you had the bone scan done, and one from the specialist who read the test.
Copyright © 2003 DePuy Acromed.