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CT Scan of the Knee With Contrast

Published: August 9, 2026Updated: August 16, 2026

A CT scan uses X-rays to create detailed images of the knee. Your care team may use contrast material to improve the images.

Quick summary

["This imaging test can help evaluate knee structures that may be difficult to assess with a standard X-ray."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
36124-6
Short code
CT Knee W contr IS
Synonyms
CT Knee W contr IS
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ct
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What is this test?

A knee CT scan is a type of X-ray imaging that creates detailed pictures of the bones and surrounding tissues in the knee. A version of the test may include contrast material to help certain areas appear more clearly.

Why might I need this test?

Your clinician may order this test to evaluate persistent knee pain, swelling, an injury, or unexplained changes seen on other images. It may help assess fractures, cartilage, bone alignment, or other structural problems.

How is the test performed?

You will lie on a padded table while an X-ray machine rotates around the affected knee. The scan is generally painless, although you may be asked to hold still or change positions.

How do I prepare for the test?

Follow the instructions provided by the imaging facility. If IV contrast will be used, ask whether you need to avoid eating, drinking, or taking certain medicines beforehand, and tell the staff about any allergies or previous contrast reactions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

The scan may reveal fractures, joint damage, cartilage changes, bone lesions, or problems involving surrounding tissues. Results are interpreted together with your symptoms, physical examination, and any other imaging tests. A radiologist will provide the findings to your ordering clinician, who will explain what they mean for your care.

Short name

CT Knee With Contrast

Frequently asked questions

Is a CT scan of the knee painful?
The scan itself is usually painless. You may briefly feel pressure from the scanner, and an injected contrast can sometimes cause a warm or flushing sensation.
How long does the test take?
Most knee CT scans take only a few minutes, although check-in, preparation, and waiting can make the overall visit longer.
Will I need someone to drive me home?
If you receive sedating medication, you will need a responsible adult to drive you home. IV contrast alone usually does not prevent you from driving, but follow the facility's specific instructions.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy