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Questions and answers about ankylosing spondylitis

What does ankylosing spondylitis mean?
What exactly is AS?
What actually happens?
Is ankylosing spondylitis the same as spondylosis?
Is AS common?
Who gets AS?
Is AS different in men, women and children?
What are the symptoms of AS?
Orange Sqr Does AS affect other joints?
Orange Sqr Does AS affect other organs?
Orange Sqr How does AS affect the eyes?
Orange Sqr How does AS affect the heart?
How does AS affect the lungs?
Does AS affect everybody the same way?
Will I need surgery ?
What medication will I need?
Is AS life-threatening?
What causes AS?
What is the risk of passing it on to my children?
Are any other diseases associated with AS?
Orange Sqr How can I be sure I have AS?
Orange Sqr Is there a cure for AS?
Orange Sqr What is the end result?
Orange Sqr The Spine

What does ankylosing spondylitis mean?

Ankylosing means fusing together. Spondylitis indicates inflammation of the vertebrae. Both words come from the Greek. So, AS describes the condition by which some or all of the joints and bones of the spine fuse together. Entire fusing of the spine is unusual. Many people will only have partial fusion, sometimes limited to the pelvic bones. - return to top

What exactly is ankylosing spondylitis?

AS is a painful, progressive, rheumatic disease. It mainly affects the spine but it can also affect other joints, tendons and ligaments. Other areas, such as the eyes, lungs, bowel and heart can also be involved. - return to top

What actually happens?

Inflammation occurs at the site where certain ligaments or tendons attach to bone (enthesis). This is followed by some erosion of bone at the site of the attachment (enthesopathy). As the inflammation subsides, a healing process takes place and new bone develops. Movement becomes restricted where bone replaces the elastic tissue of ligaments or tendons. Repetition of this inflammatory process leads to further bone formation and the individual bones which make up your backbone, the vertebrae, can fuse together. The pelvis is commonly affected first. The lower back, chest wall and neck may also become involved at different times. - return to top

Is ankylosing spondylitis the same as spondylosis?

No. They sound similar but they are different. Spondylosis is a term relating to "wear and tear" and is more common in older people. AS relates to an inflammatory condition which produces new bone and leads to fusion. The vigorous exercise therapy designed for people with AS might be harmful to those suffering from spondylosis. - return to top

Is ankylosing spondylitis common?

AS affects approximately 1 in 200 men and 1 in 500 women in Britain. - return to top

Who gets ankylosing spondylitis?

Men, women and children can all suffer from AS. It typically strikes people in their late teens and twenties, with the average age being 24. However, symptoms can start at other periods of life. AS is more common in men, with nearly three times as many men having it as women. - return to top

Is ankylosing spondylitis different in men, women and children?

Yes. AS tends to affect men, women and children in slightly different ways. Men: The pelvis and spine are most commonly affected. Other joints which may be involved are the chest wall, hips, shoulders and feet. - return to top

Women: Involvement of the spine is generally less severe than in men. The pelvis, hips, knees, wrists and ankles are the most commonly involved. Children: It is unusual for a child under the age of 11 to develop symptoms of AS. The joints which are typically affected first are the knees, ankles, feet, hips and buttocks. They rarely suffer from back pain. In youngsters, AS may lead to persistent hip disease ultimately requiring a hip replacement sometime in adult life. - return to top

What are the symptoms of ankylosing spondylitis?

Typical symptoms of AS include:

  • Slow or gradual onset of back pain and stiffness over weeks or months, rather than hours or days.
  • Early-morning stiffness and pain, wearing off or reducing during the day with exercise.
  • Persistence for more than three months (as opposed to coming on in short attacks).
  • Feeling better after exercise and feeling worse after rest.
  • Weight loss, especially in the early stages.
  • Fatigue.
  • Feeling feverish and experiencing night sweats. - return to top

Does ankylosing spondylitis affect other joints?

Yes. AS sometimes causes aching, pain and swelling in the hips, knees and ankles. Indeed, any joint can be affected. In most cases the pain and swelling will settle down after treatment. It is particularly important to stretch the hip joint to prevent stiffening in a bent position making you lean forward. The heel bone can become particularly troublesome causing pain in two areas. Most common is the under surface, about three centimeters from the back of the foot. This is called plantar fasciitis and can last for many weeks. It may respond to an insole for the shoe designed to take weight off that part of the heel. The less common pain arises at the back of the heel where the Achilles tendon is attached to the heel bone. Pressure from the shoe may aggravate the pain. - return to top

Does ankylosing spondylitis affect other organs?

Yes. AS can sometimes affect the eyes, heart and lungs. These effects are not life-threatening and they can be treated with relative ease. - return to top

How does ankylosing spondylitis affect the eyes?

AS can cause inflammation of the iris and its attachment to the outer wall of the eye, the uvea. 40% of people will develop iritis or uveitis on one or more occasions. Usually the first symptom is a slight blurring of vision in one eye but the main symptom is a sharp pain together with a dramatically bloodshot eye. To avoid permanent damage you should receive prompt treatment. It is a good idea to go straight to a casualty department, rather than to your GP, where you can be treated by an ophthalmology team. Tell them that you have AS. They will give you eye-drops which will reduce the inflammation in a matter of hours. Continue treating yourself with the eye-drops for as long as the inflammation persists. - return to top

How does ankylosing spondylitis affect the heart?

Very occasionally AS can have a mild effect on the heart. In most cases this is so mild that it is difficult to detect. AS may cause the aortic valve to leak. More commonly, though, it affects the conduction of electrical activity within the heart. Usually any such problems are unnoticed by the person with the condition. - return to top

How does ankylosing spondylitis affect the lungs?

AS should not make you any more susceptible to lung or chest infections. However, it may affect the rib joints and the muscles between the ribs making breathing, sneezing, coughing or yawning painful. As a result, the lungs fail to become fully ventilated. You will find some advice in the exercise section of this booklet to help you maintain normal chest wall movement. Sometimes the lungs may get scarred, a condition know as apical pulmonary fibrosis. This will show up on an X-ray but does not usually cause any symptoms. In the late stages of AS the chest wall may become quite fixed and affect air entry in and out of the lungs. This does not mean you stop breathing! The diaphragm muscle continues to work and your stomach moves in and out as you breathe. Large meals and tight clothing will increase the effort of breathing so you may find it more comfortable to avoid these. It is also vital to avoid smoking since this will not only make breathing more difficult but it could cause potentially serious lung and chest infections. - return to top

Does ankylosing spondylitis affect everybody the same way?

No. AS is a very variable disease. Some people have virtually no symptoms whereas others suffer more severely. However, at NASS we know that those patients who follow an appropriate course of exercises tend to do better than those who don't. - return to top

Will I need surgery ?

It is unlikely. Surgery plays a very small part in the management of this condition. About 6% of people with AS need to have a hip replaced. This will successfully restore mobility and eliminate pain of the damaged joint. In rare cases surgery is used to restore a straighter posture of the spine and neck to people who have become severely stooped. - return to top

What medication will I need?

Over 80% of people with AS take non-steroidal anti-inflammatory drugs (NSAID) to reduce inflammation and relieve pain and stiffness. However, some people may experience side-effects with NSAIDs and prefer to take simple pain killers such as paracetamol. For others, especially those who suffer from inflammatory bowel disease (Crohn's disease and ulcerative colitis) or peripheral joint arthritis, a disease-modifying antirheumatic drug like sulphasalazine may be required. - return to top

Is ankylosing spondylitis life-threatening?

Virtually never. - return to top

What causes ankylosing spondylitis?

We're not entirely sure. So far medical research has shown that 96% of people with AS in Britain all share the same genetic cell marker - Human Leucocyte Antigen B27 (HLA-B27). It is possible that some normally harmless micro-organism, which on this occasion the immune system cannot fight, comes into contact with HLA-B27 and sets up an adverse reaction. Sometimes bowel infections appear to spark off AS. Symptoms may also become apparent after a period of enforced bed rest, for example following a car accident, accelerating a previously existing mild condition. A group of symptoms known as Reiter's Syndrome may also lead to AS. These include iritis (or uveitis) which is inflammation of part of the iris; and conjunctivitis which causes red, gritty and painful eyes. People with Reiter's Syndrome also suffer from urethritis. This is inflammation of the urethra, the tube that conveys urine from the bladder out of the body. This results in pain on passing urine, discharge on the end of the penis (especially on waking up in the morning) and an increased frequency of passing urine. Women may get the pain but won't notice a discharge from the urethra. Reiter's Syndrome also results in arthritis, affecting the large joints, especially in the legs, together with pain in the joints of the lower back particularly at night or on waking. - return to top

What is the risk of passing it on to my children?

If a parent has AS there is a 50% chance that the B27 gene will be passed on to a child. However, not everyone with the B27 gene will go on to develop AS. Overall, the likelihood of your child developing AS will be less than 1 in 10 (or 1 in 5 if B27 positive). The chance of a child inheriting the condition from a grandparent will be less than 1 in 20. Should your child develop early symptoms of AS, it is advisable to ask your GP for a referral to a rheumatologist. - to top

Are any other diseases associated with ankylosing spondylitis?

A skin condition called psoriasis is associated with AS. Psoriasis causes scaly patches on the skin and scalp. It can also lead to a slightly different form of arthritis. A sexually acquired infection known as Non-Specific Urethritis (NSU) can be caused by an organism called chlamydia. This leads to urethritis and sometimes other features of Reiter's Syndrome. Ulcerative colitis or Crohn's disease are also related to AS but are not caused by it. The symptoms are bouts of bloody diarrhea, often with fever, weight loss, and an associated peripheral arthritis in some cases. - return to top

How can I be sure I have ankylosing spondylitis?

If you have the classic symptoms of AS, your GP will look at your posture to see if the lumbar spine is losing the forward curve and beginning to flatten out. If so, the GP will probably refer you to a rheumatologist who will study X-rays of your spine and look for characteristic changes to the joints in the lower back. Unlike other rheumatic conditions, blood tests are not very helpful for diagnosing AS. - return to top

Is there a cure for ankylosing spondylitis?

Alas, there is not! Anti-inflammatory drugs will help to reduce pain and improve your sleep and general well-being. But drugs are only half the answer. Appropriate exercise is crucial to managing your AS. The drugs should enable you to carry out these exercises with less pain. You will find some of these exercises later in this booklet. - return to top

What is the end result?

AS seems to affect everybody slightly differently. In general, though, you will probably find that the symptoms come and go over many years. In the classic case, the lumbar spine can become stiff, caused by the growth of additional bone, as can the upper spine and neck. If you pay attention to your posture, exercise regularly and avoid the stoop associated with the condition, you can prevent this from becoming too serious. - return to top

The Spine

The spine is made up of 24 vertebrae and 110 joints. There are 3 sections: 7 cervical, 12 dorsal or thoracic and 5 lumbar vertebrae. The cervical, or neck section, is the most mobile. In the thoracic section each vertebrae has a rib attached to it on each side. Below the lumbar section is the diamond-shaped sacrum which locks like a keystone into the pelvis. The joints between the sides of the sacrum and the rest of the pelvis are called the sacroiliac joints. This is usually the starting-point of the condition where the low back pain and AS begin.

Modified 6-10-2013    Information compiled from the National Institutes of Health






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