Ankylosing spondylitis is a type of arthritis of the spine. It causes swelling between your vertebrae, which are the disks that make up your spine, and in the joints between your spine and pelvis. Ankylosing spondylitis is an autoimmune disease. This means your immune system, which normally protects your body from infection, attacks your body's own tissues. The disease is more common and more severe in men. It often runs in families.
Early symptoms include back pain and stiffness. These problems often start in late adolescence or early adulthood. Over time, ankylosing spondylitis can fuse your vertebrae together, limiting movement. Symptoms can worsen or improve or stop altogether. The disease has no cure, but medicines can relieve the pain, swelling and other symptoms. Exercise can also help.
The onset is typically in late adolescence to early adulthood. It is rare for Ankylosing Spondylitis to begin after age 45. The disease is more common in men and in Caucasians. The incidence is 1 in 1000 persons. About 90% of people with Ankylosing Spondylitis have the HLA B27 gene. The cause of Ankylosing Spondylitis is unknown although there appears to be some genetic component. Ankylosing Spondylitis is associated with the HLA B27 gene but it is unclear why. The gene is seen in about 8% of normal Caucasians, about 10% of Ankylosing Spondylitis patients don't have the gene and only about 10% of people with the gene will get Ankylosing Spondylitis.
Early on, there is pain and stiffness in the buttocks and low back due to sacroiliac joint involvement. Over time, the symptoms can progress up the spine to involve the chest and neck. Ultimately, the bones may fuse together causing limited range of motion of the spine and limiting one's mobility. Shoulders, hips and sometimes other joints may be involved. Ankylosing Spondylitis may affect tendons and ligaments. The heel may be involved with Achilles tendonitis and plantar fasciitis. Since it is a systemic disease, patients can get fever and fatigue, eye or bowel inflammation, and rarely, there can be heart or lung involvement. Ankylosing Spondylitis is typically non life-threatening. Usually, it is a slowly progressive disease. Most people are able to work and function normally.
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 Ankylosing Spondylitis, as well as blood work including a test for HLA-B27 are factors in making a diagnosis.
The overall points taken into account when making an Ankylosing Spondylitis diagnosis are:
A physical examine will entail looking for sites of inflammation. Thus, your doctor will likely check for pain and tenderness along the back, pelvic bones, sacroiliac joints, chest and heels. During the exam, you doctor may also check for the limitation of spinal mobility in all directions and for any restriction of chest expansion.
- 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).
Other symptoms and indicators are also taken into account including a history of iritis or uveitis (inflammation of the eye), a history of gastrointestinal infections (for example, the presence of Crohn's Disease or ulcerative colitis), a family history of Ankylosing Spondylitis, as well as fatigue due to the presence of inflammation.
The Hallmark of Ankylosing Spondylitis & X-rays vs. MRI
The hallmark of Ankylosing Spondylitis 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 Ankylosing Spondylitis 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 Ankylosing Spondylitis. Also, the association between Ankylosing Spondylitis 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 Ankylosing Spondylitis test HLA-B27 positive. However, only 50% of African American patients with Ankylosing Spondylitis possess HLA-B27, and it is close to 80% among Ankylosing Spondylitis patients from Mediterranean countries.
Since there is no single blood test for Ankylosing Spondylitis, 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 Ankylosing Spondylitis 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).
You and your doctor can decide which of the following medications, if any, are best for you.
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 Ankylosing 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. 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 and Humira.
Exercise in an integral part of any Ankylosing Spondylitis management program. Regular daily exercises can help create better posture and flexibility as well as help lessen pain. Most people with Ankylosing Spondylitis feel much better with exercise.
A properly trained physical therapist with experience in helping those with ankylosing spondylitis can be a valuable guide in regards to exercise.
Practicing good posture techniques will also help avoid some of the complications of Ankylosing Spondylitis including stiffness and flexion deformities (downward curvature) of the spine.
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.
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.