Ankylosing spondylitis is inflammation primarily of the joints of the spine. But it can also involve inflammation of the eye, other joints-especially those in the hips, chest wall, and around the heels-and, on occasion, the shoulders, wrists, hands, knees, ankles, and feet. Although it is unusual, ankylosing spondylitis can also cause changes such as thickening of the major artery (aorta) and the valve in the heart called the aortic valve.
If the inflammation continues over time, it will lead to scarring and permanent damage. In some people the disease is mild and progresses slowly, and symptoms may never become severe. Other people may have a more aggressive disease process.
Whether ankylosing spondylitis gets worse depends on a number of things such as how old you were when the disease began, how early it was diagnosed, and what joints are involved. It's too early to tell yet, but experts hope that early treatment with newer medicines will slow or minimize the inflammation, prevent scarring, and limit the progression of the disease.
Mild or early ankylosing spondylitis
Ankylosing spondylitis usually starts with dull pain in the low back and back stiffness. Some people with ankylosing spondylitis have "flares" of increased pain and stiffness that may last for several weeks before decreasing again.
- Affected bones of the low back, middle back, hips, or neck may become painful, stiff, and limited in motion. Pain tends to increase slowly over a period of weeks or months, and it is often hard to point to exactly where the pain is. Stiffness is usually worse in the morning and usually lasts for more than one hour. Pain is often noticeable in the early morning hours of sleep, such as between 3 a.m. and 6 a.m. Physical activity often helps decrease pain and stiffness.
- Some people feel tired as the disease progresses. This tiredness comes from the body fighting the inflammatory process that is part of ankylosing spondylitis and also from ongoing stiffness and pain.
- The colored part of the eye (iris) may become inflamed. Symptoms of iritis include redness and pain in the eye and sensitivity to light.
Severe or advanced ankylosing spondylitis
If, over time, the inflammation continues, it will lead to scarring and permanent damage.
- Scarring in the spine causes the joints of the spine to grow together (fuse, or "ankylose").
- As the bones fuse , back pain will gradually go away, but the spine will remain very stiff and unable to bend. The fused spine is more likely to break (fracture) if injured, especially the neck (cervical spine).
- Changes in the spine can cause problems with balance, safety, and mobility. The upper spine can curve forward until eventually the person has a hard time looking straight ahead. Also, as the spine loses its natural curves, it becomes hard to balance while standing and walking, especially if the hips are also affected.
- Breathing can become difficult as the upper body curves forward and the chest wall stiffens. Severe ankylosing spondylitis can also cause scarring of the lungs (pulmonary fibrosis) and an increased risk of lung infection. This can cause even greater problems in smokers, because their lungs are already more prone to lung infection and scarring.
- Scarring in the eye from uncontrolled iritis can lead to permanent visual impairment and glaucoma.
- In rare cases, the heart muscle can become scarred and the heart valves may become inflamed. The heart may be unable to pump properly (heart failure). The main artery leading from the heart (aorta) can also be affected by becoming inflamed and enlarged near where it leaves the heart.
- Bowel inflammation is sometimes linked with ankylosing spondylitis.
- The kidneys can be affected by taking medicines over a long period of time.
- Some people who have ankylosing spondylitis for many years develop cauda equina syndrome from scarring around the nerves at the end of the spinal cord. This condition can cause loss of feeling in the saddle area of the groin and legs. It can also cause problems with bowel and bladder control and sexual activity. Talk to your doctor if you start having problems controlling your bowels or bladder.
The stiffening of the chest can feel like the discomfort or "heaviness" of a heart attack. Ankylosing spondylitis can also cause the heart to work less efficiently.
If you have any symptoms of heart or lung problems-including heaviness of the chest or pain with deep breathing-talk to a doctor right away to make sure you don't have any serious heart or lung problems. For more information on heart and lung problems, see the topics Heart Attack and Unstable Angina and Pleurisy.
Ankylosing spondylitis is one disease in a group of joint diseases called the spondyloarthropathies (say "spon-dill-o-ar-THROP-a-thees"). These include psoriatic arthritis, reactive arthritis, and enteropathic arthritis (joint problems linked with inflammatory bowel disease). Although inflammation of the spine also occurs in these other conditions, it is less common and less severe than the inflammation that occurs in ankylosing spondylitis.