Ankylosing spondylitis (AS) is a chronic form of arthritis. It mostly affects the bones and joints at the base of the spine where it connects with the pelvis. These joints can become swollen and inflamed. Over time, the affected spinal bones may join together.
AS is the main member of a family of similar forms of arthritis called spondyloarthritis. Other members include psoriatic arthritis, arthritis of inflammatory bowel disease and reactive arthritis. The family of arthritis appears to be quite common and affects up to 1 in 100 people.
The cause of AS is unknown. Genes seem to play a role. Most people with AS are positive for the HLA-B27 gene.
HLA-B27 is a blood test to look for a protein that is found on the surface of white blood cells. The protein is called human leukocyte antigen B27 (...Read Article Now Book Mark Article
The disease often begins between ages 20 and 40, but it may begin before age 10. It affects more males than females.
Ankylosing spondylitis - Animation
If you have pain and stiffness in your lower back and hips that comes and goes, you may have something called ankylosing spondylitis. Let's talk today about this condition. Ankylosing spondylitis is a long-term disease that causes inflammation of the joints between your spinal bones, as well as the joints between your spine and pelvis. We don't really know what causes it, but we think that genes play a role. We do know the disease mostly affects men, usually beginning between ages 20 and 40. It also seems to run in families. Eventually, the disease can cause spinal bones to join together, causing people to lose the ability to move their lower spine. If you have ankylosing spondylitis, you may have pain and stiffness at night, in the morning, or when you're not active. The pain may begin in the joints between your pelvis and spine and then move along your spine. Your pain may get better with movement or exercise. So, what can you do about ankylosing spondylitis? Well, your doctor will probably want you to have a number of blood and imaging tests to confirm the diagnosis. For pain, the doctor may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen. You may need to take medicines such as prednisone or other medicines to suppress your immune system. Another medicine, called a TNF-inhibitor, can block an inflammatory protein in your body and greatly improve the symptoms of ankylosing spondylitis. Ask your doctor about exercises that can help improve your posture. Lying flat on your back at night can also help your posture. Eventually, if your pain or joint damage is bad enough, you may need surgery. The course of this disease is different for everyone. For some people, symptoms may come and go at any time. The good news is that most people can function and lead a productive life unless the disease is very bad in their hips.
AS starts with low back pain that comes and goes. Low back pain becomes present most of the time as the condition progresses.
- Pain and stiffness are worse at night, in the morning, or when you are less active. The discomfort may wake you from sleep.
- The pain often gets better with activity or exercise.
- Back pain may begin in the between the pelvis and spine (sacroiliac joints). Over time, it may involve all or part of the spine.
- Your lower spine may become less flexible. Over time, you may stand in a hunched forward position.
Other parts of your body that may be affected include:
- The joints of the shoulders, knees and ankles, which may be swollen and painful
- The joints between your ribs and breastbone, so that you cannot expand your chest fully
- The eye, which may have swelling and redness
Fatigue is also a common symptom.
The spine is divided into several sections. The cervical vertebrae make up the neck. The thoracic vertebrae comprise the chest section and have ribs attached. The lumbar vertebrae are the remaining vertebrae below the last thoracic bone and the top of the sacrum. The sacral vertebrae are caged within the bones of the pelvis, and the coccyx represents the terminal vertebrae or vestigial tail.
Less common symptoms include:
- Slight fever
AS may occur with other conditions, such as:
Exams and Tests
Tests may include:
Your health care provider may prescribe medicines such as NSAIDs to reduce swelling and pain.
- Some NSAIDs can be bought over-the-counter (OTC). These include aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve, Naprosyn).
- Other NSAIDs are prescribed by your provider.
- Talk to your provider or pharmacist before daily long-term use of any over-the-counter NSAID.
You may also need stronger medicines to control pain and swelling, such as:
- Corticosteroid therapy (such as prednisone) used for short periods of time
- A biologic TNF-inhibitor (such as etanercept, adalimumab, infliximab, certolizumab or golimumab)
- A biologic inhibitor of IL17A, secukinumab
Surgery, such as hip replacement, may be done if pain or joint damage is severe.
Exercises can help improve posture and breathing. Lying flat on your back at night can help you keep a normal posture.
The course of the disease is hard to predict. Over time, signs and symptoms of AS flareup (relapse) and quiet down (remission). Most people are able to function well unless they have a lot of damage to the hips or the spine. Joining a support group of others with the same problem may often help.
Treatment with NSAIDS often reduces the pain and swelling. Treatment with TNF inhibitors early in the disease appears to slow progression of the spine arthritis.
Rarely, people with ankylosing spondylitis may have problems with:
- Psoriasis, a chronic skin disorder
- Inflammation in the eye (iritis)
- Inflammation in the intestine (colitis)
- Abnormal heart rhythm
- Scarring or thickening of the lung tissue
- Scarring or thickening of the aortic heart valve
- Spinal cord injury after a fall
When to Contact a Medical Professional
Contact your provider if:
- You have symptoms of ankylosing spondylitis
- You have ankylosing spondylitis and develop new symptoms during treatment
Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Internal review and update on 08/26/2021 by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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