Skip to content
My WebMD Sign In, Sign Up

Information and Resources

Font Size

Extremity X-Ray

An extremity X-ray is a picture of your hand, wrist, arm, foot, ankle, knee, hip, or leg. It is done to see whether a bone has been fractured or a joint dislocated. It is also used to check for an injury or damage from conditions such as an infection, arthritis, bone growths (tumors), or other bone diseases, such as osteoporosis.

X-rays are a form of radiation, like light or radio waves, that are focused into a beam, much like a flashlight beam. X-rays can pass through most objects, including the human body. X-rays make a picture by striking a detector that either exposes a film or sends the picture to a computer. Dense tissues in the body, such as bones, block (absorb) many of the X-rays and look white on an X-ray picture. Less dense tissues, such as muscles and organs, block fewer of the X-rays (more of the X-rays pass through) and look like shades of gray on an X-ray. X-rays that pass only through air, such as through the lungs, look black on the picture.

Why It Is Done

Extremity X-rays are done to:

  • Find the cause of pain in an extremity.
  • See if your bone is fractured or your joint is dislocated.
  • See if fluid has built up in the joint or around a bone.
  • See if your bones are positioned properly after treatment for a fracture or dislocation, such as after placing a cast or splint on an arm or leg. An X-ray also may be done after a doctor places a device such as a pin or an artificial joint in a bone.
  • Find changes in your bones caused by conditions such as an infection, arthritis, bone growths (tumors), osteoarthritis of the hip camera.gif, osteoarthritis of the knee camera.gif, or other bone diseases.
  • Find foreign objects such as pieces of glass or metal.
  • Check to see if a child's bones are growing normally.
  • See if your bones and joints are in the correct position after joint replacement surgery.

How To Prepare

Before the X-ray test, tell your doctor if you are or might be pregnant. Pregnancy and the risk of radiation exposure to your unborn baby (fetus) must be considered. The risk of damage from the X-rays is usually very low compared with the potential benefits of the test. If an extremity X-ray is absolutely necessary, a lead apron will be placed over your abdomen to help shield your baby from exposure to the X-rays.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

You don't need to do anything else before you have this test.

WebMD Medical Reference from Healthwise

Last Updated: April 24, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

Hot Topics

WebMD Video: Now Playing

Click here to wach video: Dirty Truth About Hand Washing

Which sex is the worst about washing up? Why is it so important? We’ve got the dirty truth on how and when to wash your hands.

Click here to watch video: Dirty Truth About Hand Washing

Popular Slideshows & Tools on WebMD

feet
Solutions for 19 types.
Woman sitting in front of UV lights
Is yours working?
Healthy breakfast
What are you eating?
Young man exercising on bike
How not to get sick at the gym.
MS Overview
Recognizing symptoms.
bowl of yogurt with heart shape
Eat for a healthy heart.
Woman scrutinizing nose in mirror
Tips that work.
close up of leg with psoriasis rash
Know what to look for.
Woman sitting with child
Do you know the symptoms?
lone star tick
How to identify that bite.
young woman in sun
What to watch for.
Thyroid exam
See how much you know.

Women's Health Newsletter

Find out what women really need.