How is osteoarthritis diagnosed?

For doctors familiar with osteoarthritis (OA), figuring out whether you have the disease usually isn't difficult. A comprehensive diagnosis is based on a doctor taking your clinical history, doing a physical exam and running some tests.

The doctor will ask you a series of questions to get information about your symptoms — when they started, where they occur, what they feel like, whether they've changed over time and how they're affecting your life.

The doctor will also ask about other diseases you may have (which could be the cause of your symptoms) and drugs you may be taking (which may interfere with some anti-arthritis drugs).

Doctors have found that answers to three questions in particular provide a good gauge of whether a patient has arthritis (or some other musculoskeletal disease) and how severely disabled he or she is:

• Do you have any pain or stiffness in your muscles, joints or back?
• Can you dress yourself completely without difficulty?
• Can you walk up and down stairs without difficulty?

The doctor then follows up any positive answers with more specific questions. The discussion should also cover:

• Pain: The location of the pain, its severity, character, and timing.
• Stiffness: No other condition causes the same type of joint stiffness as osteoarthritis.
• Swelling: Eighty-five to 90 percent of people with osteoarthritis don't experience swelling. However, swelling can indicate the degree of joint damage or suggest that there's another problem.
• Severity: The degree of pain suggests joint damage and how much treatment you may need.
• Causes: Knowing if you suffered an injury before the pain started is a valuable clue that you are suffering from secondary OA. If no injury occurred, chances increase that you have primary osteoarthritis.