Overview
Ankylosing spondylitis (pronounced ank-kih-low-sing spon-dill-eye-tiss), or AS, is a form of arthritis that primarily affects the spine, although other joints can become involved. It causes inflammation of the spinal joints (vertebrae) that can lead to severe, chronic pain and discomfort. In the most advanced cases (but not in all cases), this inflammation can lead to new bone formation on the spine, causing the spine to fuse in a fixed, immobile position, sometimes creating a forward-stooped posture. This forward curvature of the spine is called kyphosis. More information on kyphosis and fusion can be found in the complications section.
AS can also cause inflammation, pain and stiffness in other areas of the body such as the shoulders, hips, ribs, heels and small joints of the hands and feet. Sometimes the eyes can become involved (known as Iritis or Uveitis), and rarely, the lungs and heart can be affected. See the Complications of Spondylitis: How is a Person Affected? page for more information.
The hallmark feature of ankylosing spondylitis is the involvement of the sacroiliac (SI) joints during the progression of the disease, which are the joints at the base of the spine, where the spine joins the pelvis.
Is There a Cure?
Currently, there is no known cure for AS, but there are treatments and medications available to reduce symptoms and manage the pain. Recent studies show that the new biologic medications can potentially slow or halt the disease progression in some people. Please refer to the AS Treatment and Medications sections for more information.
AS is in a Group of Diseases
|
Causes of Ankylosing Spondylitis
Although the exact cause of AS is unknown, we do know that genetics play a key role in AS. Most individuals who have AS also have a gene that produces a "genetic marker" - in this case, a protein - called HLA-B27. This marker is found in over 95% of people in the caucasian population with AS (the association between ankylosing spondylitis and HLA-B27 varies greatly between ethnic and racial groups, see our AS Diagnosis section for more information). It is important to note, however, that you do not have to be HLA-B27 positive to have AS. Also, a majority of the people with this marker never contract ankylosing spondylitis.
Scientists suspect that other genes, along with a triggering environmental factor, such as a bacterial infection, are needed to trigger AS in susceptible people. HLA-B27 probably accounts for about 40% of the overall risk, but then there are other genes working in concert with B27. There are probably five or six genes involved in susceptibility toward AS. It is thought that perhaps AS starts when the defenses of the intestines start breaking down and bacteria from the intestines pass into the bloodstream directly into the region where the sacroiliac joints are located.
Who is At Risk?
The risk factors that predispose a person to ankylosing spondylitis include:
- Testing positive for the HLA-B27 marker
- A family history of AS
- Frequent gastrointestinal infections
Prevalence of AS
|
The severity of AS varies greatly from person to person, and not everyone will experience the most serious complications or have spinal fusion. Some will experience only intermittent back pain and discomfort, but others will experience severe pain and stiffness over multiple areas of the body for long periods of time. AS can be very debilitating, and in some cases, lead to disability.
Almost all cases of AS are characterized by acute, painful episodes (also known as "flares") followed by temporary periods of remission where symptoms subside.
Overheard in a Message Board Conversation, "Not all of us have flares and remissions. Some of us had rapid and severe onset that never let up, and was rather quickly degenerative." - poster Mary Beth
It is important to know that ankylosing spondylitis is a chronic, or life long disease and that the severity of AS has nothing to do with age or gender. It can be just as severe in women and children as it is in men.
Remember that even if you have AS and are experiencing only mild symptoms, which you are able to manage quite well, it is important to see your rheumatologist once a year in order to detect and treat any underlying complications.
More Information
Please visit the following sections for more information: AS Symptoms, Diagnosis, Treatment of AS and AS Medications. We also offer a wide variety of Educational Materials on ankylosing spondylitis and related diseases. Click here to view what we have to offer
Most Common Symptoms
It is important to note that the course of ankylosing spondylitis varies greatly from person to person. So too can the onset of symptoms. Although symptoms usually start to appear in late adolescence or early adulthood (ages 17-35), the symptoms can occur in children or much later.
Typically, the first symptoms of AS are frequent pain and stiffness in the lower back and buttocks, which comes on gradually over the course of a few weeks or months. At first, discomfort may only be felt on one side, or alternate sides. The pain is usually dull and diffuse, rather than localized. This pain and stiffness is usually worse in the mornings and during the night, but may be improved by a warm shower or light exercise. Also, in the early stages of AS, there may be mild fever, loss of appetite and general discomfort. It is important to note that back pain from ankylosing spondylitis is inflammatory in nature and not mechanical. For more information on mechanical vs. inflammatory back pain, please click here.
The pain normally becomes persistent (chronic) and is felt on both sides, usually persisting for at least three months. Over the course of months or years, the stiffness and pain can spread up the spine and into the neck. Pain and tenderness spreading to the ribs, shoulder blades, hips, thighs and heels is possible as well.
Note that AS can present differently at onset in women than in men. Quoting Dr. Elaine Adams, "Women often present in a little more atypical fashion so it's even harder to make the diagnoses in women." For example, anecdotally we have heard from women with AS who have stated that their symptoms started in the neck rather than in the lower back.
Varying levels of fatigue may also result from the inflammation caused by AS. The body must expend energy to deal with the inflammation, thus causing fatigue. Also, mild to moderate anemia, which may also result from the inflammation, can contribute to an overall feeling of tiredness.
 Want to know more about AS symptoms and why spondylitis hurts? Then our book, Straight Talk On Spondylitis is a perfect resource. You can click here for a sneak preview of the book, orclick here to buy now. |
Other Symptoms
In a minority of individuals, the pain does not start in the lower back, but in a peripheral joint such as the hip, ankle, elbow, knee, heel or shoulder. This pain is commonly caused by enthesitis, which is the inflammation of the site where a ligament or tendon attaches to bone. Inflammation and pain in peripheral joints is more common in juveniles with AS. This can be confusing since, without the immediate presence of back pain, AS may look like some other form of arthritis.
Many people with AS also experience bowel inflammation, which may be associated with Crohn's Disease or ulcerative colitis.
AS is often accompanied by iritis or uveitis (inflammation of the eyes). About one third of people with AS will experience inflammation of the eye at least once. Signs of iritis or uevitis are: Eye(s) becoming painful, watery, red and individuals may experience blurred vision and sensitivity to bright light. Click here for more information on the complications of AS, including iritis/uveitis.
Advanced Symptoms
Advanced symptoms can be chronic, severe pain and stiffness in the back, spine and possibly peripheral joints, as well as lack of spinal mobility because of chronic inflammation and possible spinal fusion.
Overview
A rheumatologist is commonly the type of physician that will diagnose ankylosing spondylitis, since they are doctors who are specially trained in diagnosing and treating disorders that affect the joints, muscles, tendons, ligaments, connective tissue, and bones. A thorough physical exam including x-rays, individual medical history, and a family history of AS, as well as blood work including a test for HLA-B27 are factors in making a diagnosis.
Physical Exam
The overall points taken into account when making an AS diagnosis are:
- Onset is usually under 35 years of age.
- Pain persists for more than 3 months (i.e. it is chronic).
- The back pain and stiffness worsen with immobility, especially at night and early morning.
- The back pain and stiffness tend to ease with physical activity and exercise.
- Positive response to NSAIDs (nonsteroidal anti-inflammatory drugs).
The Hallmark of AS & X-rays vs. MRI
The hallmark of AS is involvement of the sacroiliac (SI) joint (see figure to the upper right). The x-rays are supposed to show erosion typical of sacroiliitis. Sacroiliitis is the inflammation of the sacroiliac joints. Using conventional x-rays to detect this involvement can be problematic because it can take 7 to 10 years of disease progression for the changes in the SI joints to be serious enough to show up in conventional x-rays.
Another option is to use MRI to check for SI involvement, but currently there is no validated method for interpreting the results in regards to an AS diagnosis. Also, MRI can be cost prohibitive.
Blood Work & the HLA-B27 Test
First, HLA-B27 is a perfectly normal gene found in 8% of the caucasian population. Generally speaking, no more than 2% of people born with this gene will eventually get spondylitis.
Secondly, it is important to note that the HLA-B27 test is not a diagnostic test for AS. Also, the association between AS and HLA-B27 varies in different ethnic and racial groups. It can be a very strong indicator in that over 95% of people in the caucasion population who have AS test HLA-B27 positive. However, only 50% of African American patients with AS possess HLA-B27, and it is close to 80% among AS patients from Mediterranean countries.
Since there is no single blood test for AS, laboratory work may not be of much help. A simple ESR (erythrocyte sedimentation rate), also known as sed rate, is commonly an indicator of inflammation. However, less than 70% of people with AS have a raised ESR level.
Finally, there is no association with ankylosing spondylitis and rheumatoid factor (associated with rheumatoid arthritis) and antinuclear antibodies (associated with lupus).
|
Very often, a rheumatologist will be the one to outline a treatment plan, but other professionals may also be able involved in your care. (Click here for medical team information).
NSAIDs (nonsteroidal anti-inflammatory drugs) are still the cornerstone of treatment and the first stage of medication in treating the pain and stiffness associated with spondylitis. However, NSAIDs can cause significant side effects, in particular, damage to the gastrointestinal tract.
When NSAIDs are not enough, the next stage of medications, (also known as second line medications), are sometimes called disease modifying anti-rheumatic drugs (DMARDS). This group of medications include: Sulfasalazine, Methotrexate and Corticosteroids.
The most recent and most promising medications for treating ankylosing spondylitis are the biologics, or TNF Blockers. These drugs have been shown to be highly effective in treating not only the arthritis of the joints, but also the spinal arthritis. Included in this group are Enbrel, Remicade, Humira and Simponi. Click here to learn more in the medications section.
Exercise
Exercise in an integral part of any spondylitis management program. Regular daily exercises can help create better posture and flexibility as well as help lessen pain.
A properly trained physical therapist with experience in helping those with ankylosing spondylitis can be a valuable guide in regard to exercise. Click here to learn more about exercise.
Practicing good posture techniques will also help avoid some of the complications of spondylitis including stiffness and flexion deformities / kyphosis (downward curvature) of the spine. Click here to learn more about posture.
Heat/Cold
Applying heat to stiff joints and tight muscles can help reduce pain and soreness. Applying cold to inflamed areas can help reduce swelling. Hot baths and showers can also help provide relief.
Surgery
In severe cases of ankylosing spondylitis, surgery can be an option in the form of joint replacements, particularly in the knees and hips. Surgical correction is also possible for those with severe flexion deformities (severe downward curvature) of the spine, particularly in the neck, although this procedure is considered risky. Click here to learn more about surgery.
Other Symptom Management Tools
Alternative treatments such as massage and using a TENS unit (electrical stimulators for pain) can also aide in pain relief. Maintaining a healthy body weight and balanced diet can also aide in treatment. Click here for more information on alternative treatments.
