Diagnosing osteoarthritis of the knee

If you are worried about your knee pain and you think it may be due to osteoarthritis (OA), it is best that you talk to your doctor as soon as possible.

Symptoms: Pain, swelling, stiffness?

In diagnosing what the problem is, the doctor will want to know about your symptoms, where the pain is for example, and how long you have had it. Tell your doctor what type of things make the pain worse (or better). He or she will most likely examine your knee and may order one or more of the following tests to help them make a diagnosis:

Blood test

A blood test can usually rule out rheumatoid arthritis and other potential causes of joint pain, such as inflammatory diseases.


X-rays can provide a clearer picture of the cartilage and bones in your knee - a narrower than normal space between bones may indicate cartilage damage, a sign of OA.

MRI scan

If an X-ray does not provide a clear picture as to why you have knee pain, an MRI scan may offer the necessary detail as it shows blood supply and soft tissues, not just bones.

Joint fluid analysis

Joint fluid analysis involves drawing a small amount of fluid from your knee to check for signs of infection or other conditions.


A less common test for knee OA, Arthroscopy involves the insertion of a tiny camera into the knee to look directly at the joint. Arthroscopy is, however, more commonly used to treat injuries of meniscus and ligaments.