Arthritis Diagnosis & Tests

Your healthcare professional (a primary care doctor, internist, or a specialist called a rheumatologist) will use a combined approach to confirm whether or not you have arthritis or some other condition that has similar symptoms. This approach will include:

Physical Examination. Your healthcare professional will ask you about your symptoms, as well as other medical conditions you have or that run in your family. The doctor will check your reflexes, muscle strength, range of motion (how much you can move your limbs), how you stand, walk and bend, and will examine your joints for swelling or other signs of arthritis. Often, this is all that will be needed to diagnose osteoarthritis.
X-rays. These show if there is bone damage, loss of cartilage, bone spurs, debris in the joint, or other damage, especially if the condition is advanced. X-rays are especially helpful to diagnose rheumatoid arthritis.
MRI (magnetic resonance imaging). This painless, non-invasive test is able to show the soft tissues of your joints better than X-rays. It is often used for knee or shoulder problems, especially if your healthcare provider is worried you have torn a ligament or tendon.
Joint aspiration.In this test, fluid from inside the joint is drawn into a needle and examined under a microscope to look for bacteria, crystals, or certain types of inflammatory blood cells. This test is most useful to diagnose gout or infections in the joint.
Blood tests. Especially for rheumatoid arthritis, some blood tests can provide clues to the diagnosis.

Rheumatoid arthritis varies a great deal from person to person and can be difficult to diagnose at the beginning when the symptoms are mild and only a few may be present. Your doctor will order the following blood tests to help confirm the diagnosis:

Rheumatoid factor
Anti-CCP (cyclic citrullinated peptide) antibodies
White blood cell count
Red blood cell count (to look for anemia)
Sedimentation rate
C-reactive protein.