What Is Ankylosing Spondylitis?Editor's Choice
Main Category: Arthritis / Rheumatology
Also Included In: Bones / Orthopedics; Pain / Anesthetics
Article Date: 25 Jul 2012 - 0:00 PST
What Is Ankylosing Spondylitis?
|Patient / Public:|
5 (1 votes)
|Article opinions:||6 posts|
Ankylosing spondylitis is a type of chronic arthritis of the spine and the sacroiliac joints (in the pelvis). The inflammation of the vertebrae (spondylitis) can eventually lead to the fusion of the vertebrae - they cement together (ankylosis). This type of chronic arthritis affects the bones, muscles and ligaments. The long-term inflammation in the spine and sacroiliac joints cause severe pain and stiffness in the spinal area.
Ankylosing spondylitis belongs to a group of disorders known as seronegative spondyloarthropathies. Seronegative means patients do not have rheumatoid factor, an autoantibody. Spondyloarthropathies are a group of similar illnesses that generally cause joint and spine inflammation, examples include psoriatic arthritis, chronic reactive arthritis, idiopathic juvenile arthritis, and some inflammatory bowel diseases.
Some ankylosing spondylitis cases may have inflammation and pain in other parts of the body as well, such as the feet, knees, hips, ribs and shoulders. Occasionally, the area where the tendons and ligaments attach to the bones are affected, and symptoms develop in the bowel, eyes, and much more rarely the lungs and heart.
Approximately 10% of patients with ankylosing spondylitis develop long-term disabilities. In some cases, the fusing of the vertebrae results in a hunched-forward posture, making it very hard, and sometimes impossible for sufferers to lift their heads high enough to see in front of them.
Ankylosing spondylitis is three times more common in males than females. Many rheumatologists say that women with AS (ankylosing spondylitis) are undiagnosed. Women tend to have less severe symptoms than men.
Onset of symptoms usually occurs between the ages of 15 and 35 years, and very rarely when the person is elderly.
Approximately 500,000 Americans have been diagnosed with ankylosing spondylitis. According to data from various Western European health authorities, AS affects between 2 and 5 adults in every 1,000. About 200,000 people in the UK have been diagnosed with the disease.
Although ankylosing spondylitis is incurable, there are treatments and medications to alleviate the symptoms and pain, as well as slowing down the progression of the disease.
What are the signs and symptoms of ankylosing spondylitis?A sign is something other people, apart from the patient, can detect, such as a rash or a swelling. A symptom is something only the patient feels and describes to others, such as pain or dizziness.
Ankylosing spondylitis symptoms vary considerably from patient-to-patient; they can take from a few months to several years to develop fully.
Signs and symptoms usually start during a person's late teens or early adult years. Over a period of years symptoms may come and go.
Signs and symptoms commonly found with ankylosing spondylitis are:
- Back pain, back stiffness - improves with exercise, gets worse during rest, early morning symptoms are worse and improve during the day, late into the night the patient is more likely to wake up with back pain than earlier on after falling asleep.
- Pain in the buttocks
- Arthritis - inflammation of the joints. When the joint is moved it hurts, when the doctor or anybody examines the joint there is pain, the joint is swollen, and the affected area is warm
- Enthesitis - inflammation and pain where the tendons/ligaments meet the bone. Symptoms of pain may be felt behind the heel, under the heel, at the end of the ribs, and at the top of the shin bone. Sometimes pain in the ribs might make breathing painful too.
X-ray of a lateral lumber spine of a patient with ankylosing spondylitis
What are the causes of ankylosing spondylitis?Experts are not sure what causes autoimmune diseases in general. Scientists have identified a specific gene which is closely associated with the development of ankylosing spondylitis. Nine in every ten patients with AS have a specific gene, known as HLA-B27 (human leukocyte antigen B27).
Experts believe that people who carry the HLA-B27 gene have a higher risk of developing the disease. They also stress that the risk for those carrying the gene is still very small. About 80 in every 1,000 people in the general population carry the gene, but only 2 to 5 in every 1,000 people have the disease.
Testing people for HLA-B27 is not that useful, because it cannot be considered as a good method for diagnosing AS. Also, there are various subtypes of the gene.
The HLA-B27 gene can be inherited from a mother or father. Some studies have found that AS can run in families. People with a close relative who had/had ankylosing spondylitis have a threefold higher risk of developing the disease themselves compared to the rest of the population.
A British-American-Australian study in 2011 identified three regions of the genome - RUNX3, LTBR and TNFRSF1A - in which genetic variants were strongly linked to ankylosing spondylitis.They also found another four likely candidates: PTGER4, TBKBP1, ANTXR2 and CARD9.
How is ankylosing spondylitis diagnosed?If symptoms are mild, diagnosis may take some time, because the doctor and patient may just think it is a common back problem.
However, the back pain features are distinctive in that they are worse in the morning and after periods of inactivity, and improve during the day or after 30 minutes of activity; pain is also worse during the second half of the night and may wake up the patient.
The doctor may order blood tests which may help rule out some other conditions or illnesses, while at the same time providing valuable data if AS is suspected. Blood tests may include:
- FBC (full blood count) - all the different types of blood cells are measured. If the red blood cell count is low, for example, it might mean the patient is anemic.
- ESR (erythrocyte sedimentation rate) - lab technicians time how long it takes for the red blood cells to sink to the bottom of a test tube. This test may give some idea about whether there is any inflammation.
- CRP (C-reactive protein) - to measure levels of CRP in the blood. CRP is a protein that is produced in the liver. When there is inflammation, levels rise.
The rheumatologist may order the following tests:
- X-rays - to see whether there is any damage to the sacroiliac joints, and whether any new bone is forming between the vertebrae.
- MRI (magnetic resonance imaging) scan - this may reveal things an X-ray might not, such as any changes in the sacroiliac joints.
- Ultrasound scan - inflammation of the tendons and ligaments that connect to the bones is more easily detected with this type of scan.
The National Health Service, UK, uses a criteria to confirm a diagnosis of ankylosing spondylitis.
Criteria for diagnosing ankylosing spondylitis
Inflammation of the sacroiliac joints (sacroiliitis) is clearly seen on the X-ray image, plus at least one of the following:
- Back pain that improves with exercise and gets worse with rest that has persisted for at least three months
- Limited movement in the lower back (lumbar spine)
- Chest expansion is less than what is expected for the patient's age and sex
Advances in MRI techniques and technology are making it possible to diagnose AS earlier on during the disease's development.
What are the treatment options for ankylosing spondylitis?Ankylosing spondylitis is not irreversible, it cannot be cured. Treatment focuses on relieving the pain and stiffness that comes with the disease, preventing them from undermining the patient's ability to go about daily life, and slowing down the development of the disease. Experts say treatment is most effective if it can start before irreversible damage to the joints has occurred.
Although AS is a long-term condition, patients with the right treatment can live relatively normal and independent lives.
The medical team will advise the patient to receive a combination of drugs to control the pain and relieve the symptoms, plus physical therapy (UK: physiotherapy).
Physical therapy for ankylosing spondylitis
Exercise and being physically active are crucial elements in effective AS treatment. For good posture and a good range of spinal movement, the patient needs to be physically active. Exercise helps prevent the spine from being stiff and causing pain.
A qualified physical therapist who is trained in treating AS patients will draw up an exercise program that is designed for the patient. Apart from exercise routines, the therapist may also recommend massage, hydrotherapy and electrotherapy. Daily stretching is also an important part of the program.
Medication for ankylosing spondylitis
Painkillers - initially during the development of AS, the doctor will probably recommend an NSAID (non-steroidal anti-inflammatory drug), such as naproxen, ibuprofen or diclofenac. A good doctor will advise on the lowest possible dosage that provides pain relief. If NSAIDs are unsuitable, the physician may suggest acetaminophen (Tylenol, paracetamol).
For those needing stronger pain relief, they may be prescribed codeine to be taken together with the other painkiller. Codeine is made from opium or morphine and binds to opioid receptors in the central nervous system. Side effects may include nausea, vomiting, constipation and drowsiness.
Tumour necrosis factor (TNF) blocker- if painkillers, exercise and stretching are not enough to control the AS, the doctor may advise a TNF blocker. The drug is administered by injection, and prevents the effects of TNF, which reduces inflammation. Adalimumab, infliximab, golimumab and etanercept are examples of TNF blockers. Side effects may include headache, abdominal pain, nausea, a higher risk of infections, and redness or swelling at the site of the injection.
Nobody really knows what the long-term effects of TNF blockers are, because they are relatively new drugs used for AL. Patients will be monitored for a number of weeks. If treatment is not effective, the drugs will be discontinued.
Bisphosphonates - a possible complication of AS is osteoporosis. Bisphophonates are used for osteoporosis treatment, but they are sometimes useful for treating AS. If the patient develops osteoporosis, they may be prescribed bisphosphonates.
DMARDs (Disease-modifying anti-rheumatic drugs) - prescribed if other joints in the body are affected. Examples include sulfasalazine or methotrexate. Experts are still not sure how effective they are for patients with AS. Possible side effects include nausea, vomiting, heartburn and skin reactions.
A 2008 study found that ENBREL was more effective in treating AS signs and symptoms than sulphasalazine, a disease modifying antirheumatic drug (DMARD).
Corticosteroids - these are steroids and are powerful anti-inflammatory drugs. They can be taken orally or by injection. Costicosteroids can be injected straight into a joint, if necessary. Injections must be used sparingly - the same joint should not be injected more often than once every three months Possible side effects include a ruptured tendon near the joint, inflammation at the site of the injection, and depigmentation around the injection site.
In the vast majority of cases, patients with AS do not need surgery. However, if a hip joint is very damaged, it may need to be replaced.
What are the possible complications with ankylosing spondylitis?Ankylosing spondylitis affects everyone in different ways - no two people will follow a set course. If there are complications, which are much more likely if the disease is untreated, they may include:
- Uveitis (iritis) - a type of eye inflammation which causes rapid-onset eye pain, photophobia (sensitivity to light), and blurred vision. Uveitis can be easily treated with eyedrops.
- Compression fractures - in some cases the bones may become thinner during the early stages of the disease. The vertebrae may become weaker, and crumble, resulting in a stooped posture which can become quite pronounced. Sometimes the nerves that pass through the spinal cord can become damaged.
- Cardiovascular disease - people with AS have a higher risk of developing cardiovascular diseases, including heart attacks and stroke.
- Breathing problems - if the ribs are affected and the bones are fused, the patient may find it hard to inflate his/her lungs, making breathing harder.
- Inflamed aorta - this is the largest artery in the body. If the aorta is inflamed, which can happen with AS patients, it can enlarge and eventually distort the shape of the aortic valve in the heart, leading to heart problems.
- Cauda equina syndrome - a rare complication. The nerves at the bottom of the spine become compressed, resulting in pain and numbness in the lower back and buttocks, weakness in the legs which may affect walking, and urinary and/or bowel incontinence.
Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today
Visit our arthritis / rheumatology section for the latest news on this subject.Sources: National Health Service, UK; Wikipedia, Medical News Today archives, National Institutes of Health, USA.Please use one of the following formats to cite this article in your essay, paper or report:
Nordqvist, Christian. "What Is Ankylosing Spondylitis?." Medical News Today. MediLexicon, Intl., 25 Jul. 2012. Web.
24 May. 2013. <http://www.medicalnewstoday.com/articles/248217.php>
Nordqvist, C. (2012, July 25). "What Is Ankylosing Spondylitis?." Medical News Today. Retrieved from
Please note: If no author information is provided, the source is cited instead.
Contact Our News Editors
For any corrections of factual information, or to contact the editors please use our feedback form.
Please send any medical news or health news press releases to:
Note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms and conditions.