Ankylosing spondylitis is inflammation of your spine and other joints that causes pain, stiffness and swelling. It's a form of arthritis, but unlike osteoarthritis or spondylosis, which are caused by wear and tear as we age, ankylosing spondylitis usually affects younger people. In ankylosing spondylitis, your back, neck, hips or knees may slowly become less flexible, and in severe cases bones in your lower back may fuse together (ankylosis).
The most common symptoms are pain and stiffness in your lower back and buttocks. You might also notice pain or swelling in your joints, including your knees and hips.
Other symptoms can include:
You may find that your symptoms are worse:
See your GP if you have pain, stiffness or swelling in your joints that:
Your GP may refer you to a rheumatologist (specialist in muscles and joints).
Getting an accurate diagnosis for ankylosing spondylitis can take time as it can develop slowly and there’s no single test for it. Your doctor will assess your symptoms and may arrange blood tests or X-ray to check for inflammation of your spine and joints. They may also test for a specific gene that most people with ankylosing spondylitis carry.
The cause of ankylosing spondylitis isn't known, but these factors may increase risk:
Ankylosing spondylitis can't be cured, but there are treatments that can make a difference. Exercising regularly is important and taking painkillers or anti-inflammatory drugs for flare-ups can help. Other treatments for ankylosing spondylitis depend on the severity and affected joints and might include: