Knee X-ray

X-rays are usually avoided in pregnant women, as the radiation poses a slight risk of harm to the developing fetus.

The knee X-ray helps to find the cause of symptoms in the knee, such as: 

• Pain
• Tenderness
• Deformity
• Swelling
• Stiffness
• Pain with walking or inability to walk
• Weakness or instability in the knee
• Grinding in the knee

An X-ray is commonly ordered to diagnose:

• Fractured bones
• Dislocated joint

The doctor may also order an X-ray once a broken bone has been set to check if the bone is aligned properly and healing well. 

An X-ray may be performed before planning a knee surgery and to check the results after the operation. 

A knee X-ray can help detect infection, arthritis (inflamed joint), tumours and other diseases of the knee.

An X-ray may also be performed to locate foreign objects lodged in or around the knee joint.

No special preparations are needed for a knee X-ray. Inform your doctor beforehand about any problems you may have had in the past while having an X-ray.

If you are pregnant or planning a pregnancy, then you must convey this to your doctor before the X-ray.

(Read more: Family planning)

The procedure for the knee X-ray is as follows:

• The technician will ask you to remove any jewellery or metal objects that might interfere with the test. 
• If you are asked to remove some of your clothing, you will be provided with a hospital gown, which you can wear while the test is being performed.
• The technician will position you appropriately either on an X-ray table or standing. 
• They will then operate the machine from behind a wall or an adjoining room.
• You will be advised to hold very still when the images are taken.
• The technician may reposition your leg to take more images.
• The test is usually completed in five to 10 minutes.

(Read more: Knee Pain)

Typically, three X-rays are taken:

• From the front
• From the side
• With the knee bent

In some cases, the doctor may also do an X-ray of the unaffected knee for comparison.

You may feel slightly uncomfortable from the cold temperature in the examination room. 

The X-ray procedure is painless. However, holding still in the positions required for the X-rays may feel uncomfortable, especially if you have had an injury. The technician might be able to help you in finding an easier position while still ensuring good image quality.

X-rays can detect conditions of the knee, such as:

• Fracture
• Arthritis
• Infection
• Joint dislocation
• Presence of excess fluid in or around the knee
• Improper alignment of the knee joint
• Abnormalities in the bone structure
• Bone cysts (fluid-filled spaces)
• Abnormal bone growths
• Bone tumours
• Bone cancer
• Changes in the bone in certain metabolic disorders

The benefits of an X-ray are:

• Quick and easy way of diagnosing bone injuries and joint abnormalities
• Readily available in most healthcare facilities
• Useful for emergency diagnosis
• No side effects when used in the safe diagnostic range
• No radiation remains in the body after the procedure is done

(Read more: Swollen knee)

The risks associated with X-rays are:

• Slight risk of cancer due to exposure to radiation
• Risk of harm to the developing baby during pregnancy

After the test is completed, the images of the X-ray will be read and interpreted by a radiologist. The reports will be sent to your doctor who will convey them to you.

After the X-ray is done, the doctor may ask you to wait for a few minutes until the doctor can make sure that the images obtained are not blurred. If the images are blurred, the test may need to be repeated.

(Read more: Knee Sprain)

 Depending on the condition suspected, other tests that may be performed include:

• Bone scan
• Magnetic resonance imaging (MRI)
• Ultrasound imaging 
• Computed tomography (CT) scan

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.