X-Ray Exam: Foot

What It Is

A foot X-ray is a safe and painless test that uses a small amount of radiation to make an image of a person's foot. During the examination, an X-ray machine sends a beam of radiation through the foot, and an image is recorded on special X-ray film or a computer. This image shows the soft tissues and bones of the foot, which include the tarsal bones (ankle bones), metatarsal bones (front end of foot), and phalanges (toes).

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. Softer body tissues, such as the 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 a health care provider's office takes the X-rays. Three different pictures are usually taken of the foot: one from the front (anteroposterior view or AP), one from the side (lateral view), and one at an angle (oblique view).

Why It's Done

The foot X-ray can help find the cause of common signs and symptoms such as pain, tenderness, swelling, or deformities. It can detect broken bones or dislocated joints. After a broken bone has been set, an X-ray can help determine whether the bones are in proper alignment and whether they have healed properly.

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 to detect cysts, tumors, and later-stage infections of the bones.

Preparation

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

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

Procedure

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

Your child will be asked to enter a special room that will probably contain 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 either on or off the table, and then step behind a wall or into an adjoining room to operate the machine. Three X-rays are usually taken (from the front, side, and at an angle), so the technician will return to reposition the foot for each X-ray. Occasionally doctors request X-rays of the opposite foot for 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 foot 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.

The positions required for the X-rays may feel uncomfortable, but they only need to be held for 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're blurred or unclear, the X-ray may need to be redone.

Getting the Results

A radiologist, a doctor specially trained in interpreting X-ray images, will look at your child's X-rays and send a report to your doctor, who will discuss the results with you and explain what they mean.

In an emergency, the results of an X-ray can be available 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 there's some minor risk to the body with any exposure to radiation, the amount of radiation used in a foot X-ray isn't considered dangerous. 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, tell her doctor and the X-ray technician.

Helping Your Child

You can help your child prepare for a foot 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 foot X-ray is needed, speak with your doctor. You can also talk to the X-ray technician before the procedure.