What Is a Nuclear Bone Scan?
A nuclear bone scan is a medical test that uses a small amount of radioactive material to check the condition of your bones. It’s also known as skeletal scintigraphy.
You probably think of radioactivity as something to avoid. But in a medical setting, radioactive material can tell you important things about your body.
When you have the test, the radioactive material -- called a tracer or radionuclide -- will gather at places in your bones that are the site of chemical or physical changes. A scanner then picks up the radiation.
The picture made by the areas of radiation gives your doctor a kind of map of unusual areas in your bones.
Why Is a Nuclear Bone Scan Done?
Bone scans can help diagnose several problems, including:
- Broken bones, especially hips, or stress fractures, which can be hard to see on X-rays
- Paget’s disease of the bone, which affects how new tissue replaces the old
- Cancer that started in the bone
- Cancer that’s spread to your bones from another place in your body (metastatic cancer)
- Infection in your bone (osteomyelitis) or in an artificial joint such as a hip or knee
- Dead bone tissue caused by poor blood supply (avascular necrosis)
- Fibrous dysplasia, a condition passed down from your parents in which your body develops scarlike tissue instead of healthy bones
Preparing for a Nuclear Bone Scan
You can eat and drink as you usually would before your scan. You don’t have to do anything special to prepare. But certain things can interfere with the tracer, so tell your doctor if you have:
- Taken an over-the-counter medication containing bismuth (such as Pepto-Bismol)
- Recently had a test that used barium
You’ll need to remove jewelry and other metal objects before the scan. You may have to change into a hospital gown.
Nuclear Bone Scan Procedure
The first step in the procedure is the injection of the tracer material. A technician will do this through a vein in your arm or hand. You might feel a sting from the IV.
Then, you wait for the tracer to travel through your body and bind to your bones. That can take 2 to 4 hours.
Your doctor might order a scan before your body absorbs the tracer for comparison, especially if you could have a bone infection. If you’re having two scans, the first will happen right after the injection.
While your body is absorbing the nuclear material, you’ll need to drink 4 to 6 glasses of water to flush extra tracer from your body. You’ll use the restroom before the test so any concentration in your urine doesn’t cause a misleading picture.
For the scan itself, you’ll lie on a table while a camera takes pictures. You’ll have to remain very still for certain portions of the scan, and you may have to change positions several times. The scanning may take up to an hour. It’s not painful, but lying on the table may become uncomfortable.
Your doctor may also order a type of test called single-photon emission-computed tomography (SPECT). The camera rotates around your body to make more detailed images.
After a Nuclear Bone Scan
There won’t be any restrictions on your activities, such as driving, after the scan. You’ll need to drink extra fluids for a few days to flush the remaining tracer out of your system. But don’t worry about exposing others to radiation. You’re not dangerous.
Nuclear Bone Scan Risks
If you’re worried about radiation, remember that a nuclear bone scan gives you about the same exposure as regular X-rays.
It’s important to let your doctor know before the test if there’s any chance you’re pregnant, because radiation can affect your baby. Also tell them if you’re breastfeeding. You’ll need to follow precautions after the scan to avoid passing along radiation through your milk.
It usually takes about 2 days for all of the radioactive material to leave your body. You shouldn’t feel any effects from the scan, but if you have pain or redness at the site of your IV, call your doctor.
Nuclear Bone Scan Results
The camera will pick up “hot spots” where the nuclear material has gathered in your bones and “cold spots” where it did not.
The images from your scan will go first to a radiologist, or doctor who specializes in reading them. They’ll send a report to your doctor, who will talk about the results with you.
A bone scan can’t always tell what’s causing unusual spots in your bones. Your doctor may recommend that you have further tests so they can learn more.