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Ankylosing Spondylitis


The Manual's Editorial Staff

Reviewed/Revised Mar 2022 | Modified Sep 2022
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Arthritis is a group of diseases that makes your joints hurt, swell up, and turn red. There are many different types of arthritis.

What is ankylosing spondylitis?

Ankylosing spondylitis is a type of arthritis that makes your spine painful and stiff.

  • Ankylosing spondylitis, in addition to affecting your spine, also causes swelling, stiffness, and pain in your large joints, fingers, and toes

  • Sometimes it affects other parts of your body, including your eyes, lungs, and certain blood vessels

  • Doctors can tell if you have ankylosing spondylitis based on symptoms and x-rays

  • Medicines may help your pain and stiffness

Ankylosing spondylitis is 3 times more common in men than women. It usually starts in people between 20 and 40 years old.

What causes ankylosing spondylitis?

Doctors don’t know exactly what causes ankylosing spondylitis.

You're more likely to get ankylosing spondylitis if someone in your family has it.

What are the symptoms of ankylosing spondylitis?

The most common symptoms are:

  • Back pain that's usually worse at night and in the morning

  • Back stiffness in the morning that gets better once you start moving around

Sometimes, the arthritis isn't in your back at first, and you start with pain in your hips, knees, or shoulders.

Along with the back and joint pain, you may feel generally sick with symptoms like:

  • Mild fever

  • Feeling tired and run down

  • No appetite and losing weight

After awhile, if the back problem gets worse, you may have:

  • A permanent bent-over posture

  • A stiff, straight spine

  • Pressure on the nerves coming out of your spine, causing numbness, tingling, pain, and weakness in your legs

You might also have problems that don't involve your back or joints. For example, you may have:

Most people with ankylosing spondylitis develop some disabilities but can still lead normal lives. Some people, such as those with extreme stiffness in their spine, become more disabled.

How can doctors tell if I have ankylosing spondylitis?

Doctors can tell if you have ankylosing spondylitis based on your symptoms and family history and by doing an exam. They will also do tests:

How do doctors treat ankylosing spondylitis?

Doctors will give you nonsteroidal anti-inflammatory medicines (NSAIDs) and treatments to:

  • Help with your back and joint pain

  • Keep your joints movable

  • Stop or fix changes in your spine

  • Help you keep your proper posture and have strong back muscles

  • Avoid damage in your other organs

If you have eye problems, doctors may prescribe eye drops.

In addition, doctors may suggest:

  • Physical therapy and daily exercises to strengthen your muscles and stop the tendency to bend and stoop

  • Quitting or avoiding smoking

  • Rarely, hip replacement surgery, if your hips become fixed in a bent position

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