Ankylosing spondylitis is a chronic inflammatory disease that primarily causes pain and inflammation of the joints between the vertebrae of your spine and the joints between your spine and pelvis (sacroiliac joints).

What is it?

  • Ankylosing spondylitis is a chronic inflammatory disease that primarily causes pain and inflammation of the joints between the vertebrae of your spine and the joints between your spine and pelvis (sacroiliac joints). However, ankylosing spondylitis may also cause inflammation and pain in other parts of your body as well.
  • Also called spondylitis or rheumatoid spondylitis, ankylosing spondylitis is a chronic condition. Treatments for ankylosing spondylitis can decrease your pain and lessen your symptoms. Effective treatment may also help prevent complications and physical deformities that sometimes occur along with ankylosing spondylitis.

What are the Symptoms?

Initial symptoms

Early signs and symptoms of ankylosing spondylitis may include:

  • Chronic pain in your lower back and hips, especially in the morning and after periods of inactivity
  • Stiffness in your lower back or hip area

As your condition progresses

Your condition may change over time, with symptoms getting worse, improving or completely stopping at any point. Over time the pain and stiffness, which usually begin gradually, may progress up your spine and to other joints. You may experience inflammation and pain in these other parts of your body:

  • Where your tendons and ligaments attach to bones
  • Joints between your ribs and spine
  • Joints in your hips, shoulders, knees and feet
  • Your eyes

Symptoms of advanced stages

In advanced stages, the following signs and symptoms may develop:

What Causes it?

  • Ankylosing spondylitis has no known specific cause, though genetic factors seem to be involved. In particular, people who have a gene called HLA-B27 are at significantly increased risk of developing ankylosing spondylitis.
  • As ankylosing spondylitis worsens and the inflammation persists, new bone forms as part of the body's attempt to heal. Your vertebrae begin to grow together, forming vertical bony outgrowths (syndesmophytes) and becoming stiff and inflexible. Fusion can also stiffen your rib cage, restricting your lung capacity and function.

What are the Risk factors?

  • Your sex. More males than females have the disease.
  • Your age. Onset generally occurs between late adolescence and age 40.
  • Your heredity. Genetics may play a role in the development of ankylosing spondylitis. In fact, the majority of people with this condition have the HLA-B27 gene. Having this gene doesn't mean that you'll acquire ankylosing spondylitis — many people without ankylosing spondylitis have this gene — but it may make you more susceptible to the disease. If you have ankylosing spondylitis, and you pass the HLA-B27 gene on to your child, there's only a one in five chance your child will develop ankylosing spondylitis.

How is Ankylosing Spondylitis Diagnosed?

Diagnosis of ankylosing spondylitis may be delayed if your symptoms are mild or if you mistakenly attribute some of your symptoms to more common back problems.

To determine the cause of your discomfort, your doctor will conduct a medical history and complete a physical examination. Then, your doctor may use the following diagnostic procedures:

  • X-rays or other imaging. X-rays allow your doctor to check for changes in your joints and bones, though the characteristic effects of ankylosing spondylitis may not be evident early in the disease. Your doctor may also use other imaging tests, such as computerized tomography (CT) or magnetic resonance imaging (MRI) scans, to detect inflammation and other changes in your joints.
  • Blood tests. Your doctor may check for indications of inflammation using one or more blood tests, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). In the ESR test, inflammation is signaled by elevation in the speed at which your red blood cells settle to the bottom of a tube of blood. The CRP test indicates inflammation by the presence of a protein that your liver produces as part of your immune system response to injury or infection.

Other tests used to diagnose ankylosing spondylitis include a complete blood count (CBC) to determine if you have anemia, a condition in which there aren't enough healthy red blood cells to carry adequate oxygen to your tissues. Anemia is a complication that can result from the chronic inflammation of ankylosing spondylitis. Finally, your doctor may check your blood for the HLA-B27 gene. The presence of this gene doesn't determine whether you have ankylosing spondylitis, but its absence makes it less likely.


The goal of treatment is to relieve your pain and stiffness, and prevent or delay complications and spinal deformity. Ankylosing spondylitis treatment is most successful before the disease causes irreversible damage to your joints, such as fusion, especially in positions that limit your function.


Your doctor may recommend that you take one or more of the following medications:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs — such as naproxen (Naprosyn) and indomethacin (Indocin) — are the medications doctors most commonly use to treat ankylosing spondylitis. They can relieve your inflammation, pain and stiffness. However, these medications aren't without side effects. One of the more serious side effects attributed to NSAID use is gastrointestinal bleeding. Rarer side effects include kidney and liver problems.
  • Disease-modifying antirheumatic drugs (DMARDs). Your doctor may prescribe a DMARD, such as sulfasalazine or methotrexate, to treat inflamed joints of the legs and arms and other tissues. This class of drugs helps limit the amount of joint damage that occurs. Serious side effects that can occur while using these medications include low blood counts and liver damage.
  • Corticosteroids. These medications, such as prednisone, may suppress inflammation and slow joint damage in severe cases of ankylosing spondylitis. You usually take them orally, ideally for a limited period of time because of their side effects, such as bone loss. Occasionally, corticosteroids are injected directly into a painful joint.
  • Tumor necrosis factor (TNF) blockers. TNF is a cytokine, or cell protein, that acts as an inflammatory agent in rheumatoid arthritis. TNF blockers target or block this protein and can help reduce pain, stiffness, and tender or swollen joints. These medications, such as adalimumab (Humira), etanercept (Enbrel) and infliximab (Remicade), may decrease inflammation and improve pain and stiffness for people with ankylosing spondylitis. When taking these medications, there's a risk of reactivating latent infections, such as tuberculosis, as well as a risk of certain neurological problems.

Physical therapy

  • Physical therapy can provide a number of benefits, from pain relief to improved physical strength and flexibility. Your doctor may recommend that you meet with a physical therapist to provide you with specific exercises designed for your needs.
  • Range-of-motion and stretching exercises can help maintain flexibility in your joints and preserve good posture. In addition, specific breathing exercises can help to sustain and enhance your lung capacity.
  • As your condition worsens, your upper body may begin to stoop forward. Proper sleep and walking positions and abdominal and back exercises can help maintain your upright posture. Though you may develop spine stiffness despite your treatment regimen, proper posture can help to ensure that your spine is fused in a fixed upright position.


  • Most people with ankylosing spondylitis don't need surgery. However, your doctor may recommend surgery if you have severe pain or joint damage, or if a nonspinal joint is so damaged that it needs to be replaced. 

Lifestyle choices

If you smoke, quit. Smoking is bad for your health, but creates additional problems for people with ankylosing spondylitis. Depending on the severity of your condition, ankylosing spondylitis can affect the mobility of your rib cage. Damaging your lungs by smoking can further compromise your ability to breathe.

Coping with Ankylosing Spondylitis

  • The course of your condition may change over time, and you may experience relapses and remissions throughout your life. But despite the potential complications, most people are able to live productive lives despite a diagnosis of ankylosing spondylitis.
  • You may want to join a support group of other people with this condition, in order to share experiences and support. 

Can Ankylosing Spondylitis be Prevented?

  • Because genetic factors appear to play a part in ankylosing spondylitis, it's not possible to prevent the disease. However, being aware of any personal risk factors for the disease can help in early detection and treatment. Proper and early treatment can relieve joint pain and may help to prevent or delay the onset of physical deformities.