Glossary
Knee X-ray
Quick answer
A knee X-ray is a quick, low-dose picture of the bones of the knee. It shows fractures, arthritis, joint space narrowing, bone spurs, loose bodies and alignment, but not ligaments, the meniscus or cartilage directly. It is often the first scan Doha knee surgeon Dr. Pablo Gelber requests at Aman Hospital.
What to expect
An X-ray takes a few minutes and is painless. You stand or lie while the radiographer positions the knee and takes pictures from the front, the side and often a view of the kneecap with the knee bent. You may be asked to remove jewellery or clothing with metal. The radiation dose for a knee X-ray is small.
What it shows
Bone is white on an X-ray, while soft tissues such as ligaments and the meniscus are grey and hard to see. So an X-ray is good at showing fractures, the shape of the kneecap and groove, bone spurs, calcification, loose fragments of bone, and how much space is left between the bones, which reflects the thickness of the cartilage.
That is why a normal X-ray does not rule out an ACL or meniscus tear. If the examination suggests a soft-tissue injury, an MRI usually follows. On the other hand, in an older patient with suspected arthritis, an X-ray often gives more practical information than an MRI.
Why surgeons ask for X-rays first
Even when an MRI is planned, X-rays help rule out a fracture, show arthritis that changes the treatment plan, and give a baseline for future comparison.
Frequently asked questions
My X-ray was normal but my knee still hurts. Why?
Many painful problems, such as meniscus tears, ligament injuries and early cartilage damage, do not show on X-ray. Your surgeon may examine the knee and recommend an MRI if needed.
Is a knee X-ray safe in pregnancy?
Tell the radiographer if you may be pregnant. The knee is far from the abdomen and a shield can be used, but the decision is made case by case.
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