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What is ankylosing spondylitis?


Ankylosing spondylitis (AS) is a form of arthritis that affects the lower back. "Spondylitis" refers to inflammation of the spine while the term "ankylosing" means the fusing together of bones.

In patients suffering from AS, the discs and ligaments between the lower vertebrae and become inflamed causing pain and stiffness.

Over time these tissues can become eroded, causing new bone to be formed in its place, and the vertebrae to fuse together.AS typically first occurs in young adults between the ages of 15 and 35. More men than women are affected, to a ratio of about 3 to 1 and it is believed that there is an inherited component to the condition. The cause of AS is not fully understood. It is classified as an auto-immune disease (similarly to Rheumatoid Arthritis), whereby the body's own defense systems appear to attack normal tissues and functions. Overall, it is estimated that about 1 in 1000 adults are affected by AS.

AS first appears as pain and stiffness that starts in the lower back. Over several months the pain may spread to the buttocks and lower thighs. The pain is usually worse on waking in the morning and eases throughout the day. In many sufferers, pain and inflammation can appear in other joints.

Although there is no cure for AS, the long term outlook is good. AS tends to go through flare-ups, followed by periods of low-level symptoms. The condition is treated by a combination of medication and exercise. About 1 in 10 sufferers may experience significant disability because of the condition.


Lower back pain, often radiating to the legs. Mobility and flexibility of the spine is progressively reduced. Inflammation of other joints may occur, there may also be inflammation of the eye.


Anti-inflammatory drugs are used to treat the pain and inflammation symptoms, but do not stop progression of the disease. Injectible drugs known as anti-TNFs are used in severe AS to halt progression.


It is important to maintain a regular exercise routine with AS. Low impact activity, such as swimming is particularly recommended. Other measures to improve posture and breathing can also be helpful.

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