Bone Scan

(Bone Scintigraphy)

Procedure Overview

What is a bone scan?

A bone scan is a specialized radiology procedure used to examine the various bones of the skeleton to identify certain conditions. A bone scan may also be used to follow the progress of treatment of certain conditions.

A bone scan is a type of nuclear radiology procedure. This means that a tiny amount of a radioactive substance is used during the procedure to assist in the examination of the bones. The radioactive substance, called a radionuclide (radiopharmaceutical or radioactive tracer), will collect within the bone tissue at spots of abnormal metabolism or bone tissue growth.

The radionuclide most frequently used in bone scans is called technetium diphosphonate. The radionuclide emits a type of radiation, called gamma radiation. The gamma radiation is detected by a scanner, which processes the information into a picture of the bones.

The areas where the radionuclide collects are called "hot spots," and may indicate the presence of conditions such as malignant (cancerous) bone tumors, metastatic bone cancer (cancer which has spread from another site, such as the lungs), bone infections, bone trauma not seen on ordinary x-rays, and other conditions of the bone.

Other related procedures that may be used to diagnose bone problems include x-rays of the extremities or of the spine, computed tomography (CT scan) of the bones, magnetic resonance imaging (MRI) of the bones, or a bone biopsy. Please see these procedures for additional information.

Reasons for the Procedure

Bone scans are used primarily to detect the spread of metastatic cancer. Because cancer cells multiply rapidly, they will appear as a hot spot on a bone scan. This is due to the increased metabolism, or cell activity, of the cancer cells. Bone scans may also be performed on cancer patients to stage the cancer before and after treatment in order to assess the effectiveness of the treatment.

Other reasons for performing a bone scan procedure may include, but are not limited to, the following:

• to assess for bone trauma in situations where ordinary x-rays do not reveal trauma
  
  
• to detect fractures that are difficult to locate
  
  
• to determine the age of fractures
  
  
• to detect and/or assess bone infections (osteomyelitis)
  
  
• to monitor certain degenerative bone disorders
  
  
• to assess unexplained bone pain
  
  
• to detect conditions such as arthritis, benign bone tumors, Paget's disease (a bone disorder, usually occurring in people over age 50, in which there is chronic inflammation of the bones, leading to thickening and softening of the bones, and curving of the long bones), and aseptic necrosis (death of bone tissue not due to infection)

There may be other reasons for your physician to recommend a bone scan.

Risks of the Procedure

The amount of the radionuclide injected into your vein for the procedure is small enough that there is no need for precautions against radioactive exposure. The injection of the radionuclide may cause some slight discomfort. Allergic reactions to the radionuclide are rare, but may occur.

For some patients, having to lie still on the scanning table for the length of the procedure may cause some discomfort or pain.

Patients who are allergic to or sensitive to medications, contrast dyes, shellfish, or latex should notify their physician.

If you are pregnant or suspect that you may be pregnant, you should notify your physician due to the risk of injury to the fetus from a bone scan. If you are lactating, or breastfeeding, you should notify your physician due to the risk of contaminating breast milk with the radionuclide.

There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.

Before the Procedure

• Your physician will explain the procedure to you and offer you the opportunity to ask questions that you might have about the procedure.
  
  
• You may be asked to sign a consent form that gives your permission to do the test. Read the form carefully and ask questions if something is not clear.
  
  
• Generally, no prior preparation, such as fasting or sedation, is required prior to a bone scan.
  
  
• Notify the radiologist or technologist if you are allergic to or sensitive to medications, contrast dyes, or iodine.
  
  
• If you are pregnant or suspect you may be pregnant, you should notify your physician.
  
  
• Based upon your medical condition, your physician may request other specific preparation.

During the Procedure

Bone Scan

A bone scan may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician's practices.

Generally, a bone scan follows this process:

1. You will be asked to remove any clothing, jewelry, or other objects that may interfere with the procedure.
   
   
2. If you are asked to remove clothing, you will be given a gown to wear.
   
   
3. An intravenous (IV) line will be started in the hand or arm for injection of the radionuclide.
   
   
4. The radionuclide will be injected into your vein. The radionuclide will be allowed to concentrate in the bone tissue for a period of one to three hours. You may be allowed to walk around or even leave the facility during this time. You will not be hazardous to other people, as the radionuclide emits less radiation than a standard x-ray.
   
   
5. During the waiting period, you will need to drink several glasses of water (four to six glasses) to help flush out the radionuclide substance that does not concentrate into the bone tissue.
   
   
6. If your bone scan is being done to detect bone infection, a set of scans may be done immediately after the injection of the radionuclide. Another set of scans will be done after the radionuclide has been allowed to concentrate in the bone tissue.
   
   
7. When the radionuclide has been allowed to concentrate in the bone tissue for the appropriate amount of time, you will be asked to empty your bladder prior to the start of the scan. A full bladder can distort the bones of the pelvis, and may become uncomfortable during the scan, which may take up to an hour to complete.
   
   
8. You will be asked to lie still on a scanning table, as any movement may affect the quality of the scan.
   
   
9. The scanner will move slowly over you several times as it detects the gamma rays emitted by the radionuclide in the bone tissue.
   
   
10. You may be repositioned during the scan in order to obtain particular views of the bones.
    
    
11. When the scan has been completed, the IV line will be removed.

While the bone scan itself causes no pain, having to lie still for the length of the procedure might cause some discomfort or pain, particularly in the case of a recent injury or invasive procedure such as surgery. The technologist will use all possible comfort measures and complete the procedure as quickly as possible to minimize any discomfort or pain.

After the Procedure

You should move slowly when getting up from the scanner table to avoid any dizziness or lightheadedness from lying flat for the length of the procedure.

You will be instructed to drink plenty of fluids and empty your bladder frequently for 24 to 48 hours after the procedure to help flush the remaining radionuclide from your body.

The IV site will be checked for any signs of redness or swelling. If you notice any pain, redness, and/or swelling at the IV site after you return home following your procedure, you should notify your physician as this may indicate an infection or other type of reaction.

You should not have any other radionuclide procedures for the next 24 to 48 hours after your bone scan.

You may resume your usual diet and activities, unless your physician advises you differently.

Online Resources

The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your physician. Please consult your physician with any questions or concerns you may have regarding your condition.

This page contains links to other Web sites with information about this procedure and related health conditions. We hope you find these sites helpful, but please remember we do not control or endorse the information presented on these Web sites, nor do these sites endorse the information contained here.

American Academy of Orthopaedic Surgeons

American Cancer Society

Arthritis Foundation

National Cancer Institute

National Institute of Arthritis and Musculoskeletal and Skin Diseases

National Institutes of Health (NIH)

National Library of Medicine