In most cases, your doctor can tell you if you have osteoarthritis and recommend treatment based on your symptoms and by doing a physical exam. Your doctor may also do some other tests to be sure that the diagnosis is correct or to rule out other conditions that have similar symptoms.

These tests may include:

• A joint fluid study. A sample of the fluid that cushions the joint is removed and sent to the lab to look for the cause of joint pain and swelling.
• X-rays. Pictures of the bones in a joint, such as the hip or knee , are taken to look for cartilage damage.
• An arthroscopy. A thin, lighted tube called an arthroscope is placed inside a small cut made near the joint. The doctor uses the scope to look for problems on the surfaces of the joint and the soft tissues that surround it. This test is not done very often.

Other tests may include a urine test and one or more blood tests, such as:

• Complete blood count (CBC).
• Rheumatoid factor (RF).
• Antinuclear antibody (ANA).
• Sedimentation rate (sed rate).
• C-reactive protein (CRP).
• Chemistry screen.
• Thyroid-stimulating hormone (TSH).
• Ferritin.