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What It Is

A wrist X-ray is a safe and painless test that uses a small amount of radiation to make an image of a person's wrist. During the examination, an X-ray machine sends a beam of radiation through the wrist, and an image is recorded on special X-ray film or a computer screen. This image shows the soft tissues and the ends of the forearm bones (radius and ulna) and eight small wrist bones (carpal bones).

The X-ray image is black and white. Dense structures that block the passage of the X-ray beam through the body, such as the bones, appear white on the image. Softer body tissues, such as the skin and muscles, allow the X-ray beams to pass through them and appear darker.

An X-ray technician in the radiology department of a hospital or in a health care provider's office takes the X-rays. Two different pictures are usually taken of the wrist: one from the back, with the palm facing down (posteroanterior view, or PA), and one from the side (lateral view). Sometimes an X-ray is taken with the wrist at an angle (oblique view).

Why It's Done

A wrist X-ray can help find the cause of common signs and symptoms such as pain, tenderness, swelling, or show deformities of the wrist joint. It can also detect broken bones or dislocated joints. After a broken bone has been set, an X-ray can help determine whether the bones are in alignment.

If surgery is required, an X-ray may be taken to plan for the surgery and to assess the results of the operation. Also, an X-ray can help detect infections, bone cysts, tumors, or other diseases in the bones. A wrist X-ray may also be done as part of a bone-age study, which can help doctors determine if there is a growth abnormality.

Preparation

A wrist X-ray doesn't require any special preparation. Your child may be asked to remove clothing, jewelry, or any metal objects that might interfere with the image.

If your daughter is pregnant, it's important to tell the X-ray technician or her doctor. X-rays are usually avoided during pregnancy because there's a small chance the radiation may harm the developing baby. But if the X-ray is necessary, precautions can be taken to protect the fetus.

Procedure

Although the procedure may take about 15 minutes, the actual exposure time to radiation is usually less than a second.

Your child will be asked to enter a special room that probably will have a table and a large X-ray machine hanging from the ceiling. Parents are usually able to come in with their child to provide reassurance. If you stay in the room while the X-ray is being done, you'll be asked to wear a lead apron to protect certain parts of your body. Your child's reproductive organs will also be protected with a lead shield.

The technician will position your child's wrist, and then step behind a wall or into an adjoining room to operate the machine. Two to three X-rays are usually taken (from the front, side, and from an angle), so the technician will come back to reposition the wrist for each X-ray. Occasionally doctors request an X-ray of the opposite wrist to use as a comparison.

Older kids will be asked to stay still for a few seconds while the X-ray is taken; infants may require gentle restraint. Keeping the wrist still is important to prevent blurring of the X-ray image.

What to Expect

Your child won't feel anything as the X-ray is taken. The X-ray room may feel cool due to the air conditioning used to maintain the equipment.

Positions required for the X-ray may feel uncomfortable, but they need to be held for only a few seconds. If your child has an injury and can't stay in the required position, the technician might be able to find another position that's easier on your child. Babies often cry in the X-ray room, especially if they're restrained, but this won't interfere with the procedure.

After the X-rays are taken, you and your child will be asked to wait a few minutes while the images are processed. If they are blurred or unclear, some of the views may need to be redone.

Getting the Results

The X-rays will be looked at by a radiologist (a doctor who is specially trained in reading and interpreting X-ray images). The radiologist will send a report to your doctor, who will discuss the results with you and explain what they mean.

In an emergency, the results of a wrist X-ray can be available very quickly. Otherwise, results are usually ready in 1-2 days. In most cases, results can't be given directly to the patient or family at the time of the test.

Risks

In general, X-rays are very safe. Although exposure to radiation poses some risk to the body, the amount used in a wrist X-ray is small and not considered dangerous. It's important to know that radiologists use the minimum amount of radiation required to get the best results.

Developing babies are more sensitive to radiation and are at more risk for harm, so if your daughter is pregnant, be sure to tell her doctor and the X-ray technician.

Helping Your Child

You can help your child prepare for a wrist X-ray by explaining the test in simple terms before the procedure. It may help to explain that getting an X-ray is like posing for a picture.

You can describe the room and the equipment that will be used, and reassure your child that you'll be right there for support. For older kids, be sure to explain the importance of staying still while the X-ray is taken so it won't have to be repeated.

If You Have Questions

If you have questions about why the wrist X-ray is needed, speak with your doctor. You can also talk to the X-ray technician before the procedure.