Learn about Osteoarthritis diagnosis at Consumer Reports Health.

Osteoarthritis

How does my doctor diagnose osteoarthritis?

There is no one test for osteoarthritis. Your doctor will probably make the diagnosis by examining you, performing tests, asking you questions and seeing what an X-ray reveals about your joints.

Osteoarthritis can be confused with other joint diseases, but these are rarer than osteoarthritis.

Doctors take several things into account when diagnosing osteoarthritis, such as which of your joints are affected and what X-rays show.

Quesions about your symptoms

Your doctor may ask if you have any of these symptoms.

Joint pain: This varies from a dull ache to a stabbing pain. It's worse when you move, and it gets better when you rest. Pain at night suggests severe osteoarthritis.
Morning stiffness: This lasts less than 30 minutes usually (stiffness for more than 45 minutes is more typical of another joint disease,

rheumatoid arthritis
If you have rheumatoid arthritis, your joints get painful, swollen and stiff. Rheumatoid arthritis is caused by inflammation inside your joints. It happens when your immune system attacks the lining of your joints.

rheumatoid arthritis).
Limited movement: You may not be able to climb in and out of the bath or go up and down stairs.
Difficulty doing everyday things: You may find it hard to do things like comb your hair, and you may even have difficulty doing your job.
Depression: This is not a symptom of arthritis, but you may become depressed by having the condition. You may find that your life is restricted and that you feel isolated.

Source:
Manek NJ, Lane NE.
Osteoarthritis: current concepts in diagnosis and management.
American Family Physician. 2000; 61: 1795-1804.

¹
If you have osteoarthritis of the hand: Your hand may be painful, ache and feel stiff. The small joints at the ends of your fingers and the base of your thumb are the parts most likely to be affected.

Researchers use what's called a physician's global evaluation of pain to measure if your pain improves with treatment.

Source:
Insall JN, Dorr LD, Scott RD, et al.
Rationale of the Knee Society clinical rating system.
Clinical Orthopaedics and Related Research. 1989; 248: 13-14.

Completely gone (score 3): You have had no joint pain (such as knee pain) from arthritis for three or more days.
Much better (score 2): Your pain has gotten a lot better while taking medication, but you still have some pain.
Slightly better (score 1): Your pain has gotten slightly better, but you are still in quite a lot of pain.
Same (score 0): Your pain hasn't changed.
Worse (score -1): Your pain has gotten worse and you feel it more often.

Doctors use a variety of measures to work out how severe your symptoms are. They may ask you about the following.

Source:
Bellamy N, Buchanan WW, Goldsmith CH, et al.
Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee.
Journal of Rheumatology. 1988; 15: 1833-1840.

Pain: for example, when walking or climbing stairs, or at night or at rest
Stiffness: in the morning or later in the day
Difficulty doing things: for example, going down and up stairs, getting up from a chair, standing, bending, getting in and out of a car, going shopping, putting your socks on, getting in and out of the bath
Social activities: how often you go out with your family or friends, or go to church or to clubs

Which joints are affected?

Osteoarthritis most commonly affects:

Small joints at the ends of the fingers and the base of your thumb
The knee joint (this affects 10 percent of people over age 60: knee osteoarthritis is 50 percent more common than hip osteoarthritis in people over 60)
The hip joint (this affects 5 in 100 people over 60)
The neck and lower spine.

Examining your joints

Your doctor will look at your joint, ask you to move your joint and then move it for you. The clues that you may have osteoarthritis are:

Your joint is larger than normal and knobby
You can't move it as much as normal
Your joint hurts if your doctor tries to move it past the point where you can move it without pain
There is creaking on moving your joint
Your muscles aren't as strong as they should be
You have some tenderness around your joint or some fluid on the joint.

Having an X-ray

Your doctor will look to see if your X-ray has the key signs of osteoarthritis. But even if your X-ray shows that your disease is severe, your symptoms may not be bad. Here's what an X-ray may reveal.

An X-ray may show bony spurs and other signs of osteoarthritis.

The space in the joint is smaller: Usually there is a space in the joint between the bones. In osteoarthritis, this space is reduced because of the loss of cartilage, and the abnormal overgrowth and reshaping of the bone.
Your joint has bony spurs: Your doctor will see if you have any bony spurs, called osteophytes, around your joint. Spurs are due to abnormal bone growth and are a very important sign of osteoarthritis on an X-ray.
Your bone may be thicker in some places and thinner in others: Your X-ray may show sections of bone that are whiter than usual (your doctor may call this sclerosis). This is caused by the bone cells being more active than normal in that area. In other places, the bone in the joint may look patchy and more see-through because the bone is being destroyed. These thin areas are sometimes called

cysts
A cyst is a sac or cavity that develops under your skin and is filled with fluid. Cysts are benign, which means that they are not cancerous.

cysts and suggest osteoarthritis.

Other tests

Doctors may do some additional tests, such as blood tests, to rule out other diseases that can be confused with osteoarthritis, such as rheumatoid arthritis,

gout
This is a disease of the joints that is caused by a buildup of a chemical called uric acid. This chemical actually forms a crystal within the blood that gets stuck in the joints, causing swelling and pain. Gout attacks often occur in the big toe, but the disease can affect other joints in the body as well. Attacks are excruciatingly painful, but, fortunately, can be treated with a variety of medicines and a special diet.

gout or

Lyme disease
This is an infection transmitted by some tick bites. It can lead to severe, flulike symptoms, including fatigue, fever, headache, muscle pain and a rash. Lyme disease can be treated with antibiotics. In rare cases, if the infection is not treated, people can develop more serious problems, such as arthritis in their joints and problems with their nervous system and heart. Lyme disease is typically seen in the Northeast and North Central United States.

Lyme disease. Your doctor may also draw off some fluid from your joint and test it for white blood cells or crystals. White blood cells are the cells of the

immune system
The immune system is made up of the parts of the body that are devoted to fighting infection. The body is constantly being threatened by infections from things like bacteria, viruses and parasites. The immune system fights these infections in different ways. At the microscopic level, the immune system uses antibodies and white blood cells, which travel in the blood and target infectious agents, such as bacteria. These microscopic parts of the immune system either kill the infectious agent directly, or take it to other parts of the body, like the spleen, where it can be dealt with. The lymph nodes are another important part of the immune system. Within them, white blood cells filter through the foreign material that has entered the blood, to see if there are any infections. When you have a swollen gland during a cold, this is actually a lymph node that is reacting to the infection. Unfortunately, it is possible for the immune system to become confused and to use its destructive powers to target healthy parts of the body. Diseases that result from this type of situation are called autoimmune diseases.

immune system that are involved in fighting inflammation. If there are lots of them in your fluid, it may mean you have rheumatoid arthritis or an infection such as Lyme disease. If there are crystals in your joint fluid it may mean you have gout.

Your doctor may also want to do extra tests to see if you have a condition that can cause osteoarthritis. Most cases of osteoarthritis just happen, but some cases are caused by:

Trauma to your ligaments, bones or cartilage
Overuse, such as from intense exercise or physical work
Looseness of the joint, which may make it unstable and wear out more quickly
Joint deformities, such as

bowlegs
These are legs that curve out at the knees. A common cause is rickets. In rickets, the body is not getting enough vitamin D, which means it can't absorb enough calcium. Bones that are made without enough calcium are brittle and can be misshapen. Bowlegs can cause osteoarthritis, because there is too much weight being placed on one side of the knee joint, causing damage to the cartilage.

bowlegs
Infection of the bone or joint
Problems with your nerves that make it hard for you to feel things (your doctor may call this neuropathy). This could be caused by underlying diseases such as

diabetes
Diabetes is a condition that causes too much sugar to circulate in your blood. It happens when your body stops making a hormone called insulin (type 1 diabetes) or when insulin stops working (type 2 diabetes).

diabetes.

Sources for the information on this page:

Manek NJ, Lane NE.Osteoarthritis: current concepts in diagnosis and management.American Family Physician. 2000; 61: 1795-1804.

Insall JN, Dorr LD, Scott RD, et al.Rationale of the Knee Society clinical rating system.Clinical Orthopaedics and Related Research. 1989; 248: 13-14.

Bellamy N, Buchanan WW, Goldsmith CH, et al.Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee.Journal of Rheumatology. 1988; 15: 1833-1840.

This information was last updated on Jan 07, 2009

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment.
© BMJ Publishing Group Limited 2009. All rights reserved.

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