Ankylosing Spondylitis

Ankylosing Spondylitis


  • Onset of symptoms rarely occurs after age 40
  • AS afflicts an estimated 129 out of 100,000 people in the United States. 

What is Ankylosing Spondylitis?

Ankylosing Spondylitis is a form of arthritis that mainly involves the spine and joints of the extremities, such as the shoulders, hips and knees. Normal tissue that connects the vertebrae is gradually replaced by bone-like fibers, which fuse the spine and limit movement. It can also cause inflammation of the eyes, lungs, and heart It strikes primarily young men. When it does occur in females, it is harder to diagnose and the symptoms are often less severe.

AS is a member of the family of diseases that attack the spine called spondylarthropathies, this group also includes Reiter’s syndrome, some cases of psoriatic arthritis and the arthritis that accompanies inflammatory bowel disease.

What causes it?

Genetics appear to have a strong role in the cause of AS. All of the spondylarthropathies share a common genetic marker, called HLA-B27, which occurs in most affected individuals.

What are the symptoms?

The most common symptom of AS is low back pain and stiffness, the upper back and neck can also be involved. The shoulders, knees and hips may be swollen, stiff and painful. Fever, fatigue and weight loss are common. Eye inflammation and inflammation of the heart valves can occur in more severe cases.

How is it diagnosed?

No one test can diagnose AS. Diagnosis is made based on medical history, physical exam, blood tests and x-rays. The HLA-B27 tissue antigen is present in 90% of patients compared to 5-8% incidence in general population.

How is it treated?

Treatment of AS is tailored to the individual. Each treatment plan usually consists of several different types of treatment.

Proper posture is crucial when dealing with AS. Every effort must be made to keep the spine straight. Physical therapists can instruct a person on how to maintain proper posture and may be able to teach some exercises to strengthen the back. A firm mattress is recommended to keep the spine aligned during sleep.

Exercise is another very important part of treating AS. Exercises that strengthen the back and neck will help maintain or improve posture. Deep breathing exercises and aerobic exercises will help keep the chest and rib cage flexible. Swimming is a great way to exercise since it promotes flexibility of the spine; movement of the neck, shoulder, and hip joints; and deep breathing.

NSAIDS (Nonsteroidal anti-inflammatory drugs) are commonly used to treat AS. Available over the counter or by prescription, they fight inflammation or swelling and relieve pain. NSAIDS may relieve pain and swelling, but they do not slow the disease process.

DMARDS (disease modifying anti-rheumatic drugs) are also known as SAARDS (slow acting anti rheumatic drugs. As their name might suggest these medications take some time to be effective, up to several months. Although not used in AS as frequently as some of the other types of arthritis, they can be effective in some cases.

What research is being done?

Scientists suspect that other genes are involved in AS. Genetic studies of families who have multiple members with AS are underway. The goal is to determine what genes influence disease onset, severity and distribution of symptoms.

Some of the related information found on Arthritis Insight:

For support visit our Chat Room and Message Boards.
For medication information see our Medication Index.
For more sites about AS check out our Web Links.

For more information:

Spondyloarthropathy: by drdoc on-line
EnAble Center for Ankylosing Spondylitis

The Ankylosing Spondylitis Site


Dambro: Griffith’s 5-Minute Clinical Consult, 1999 ed., Copyright © 1999 Lippincott Williams & Wilkins, Inc.
American College of Rheumatology
Spondylitis Association of America
Ankylosing Spondylitis ,Frederick Matsen III MD Chairman, Department of Orthopaedics, University of Washington, Seattle, USA