Ankylosing spondylitis

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at April 19, 2016
StartDiseasesAnkylosing spondylitis

Ankylosing spondylitis or AS is an inflammatory disease where the vertebrae mutate and fuse together, causing stiffness, pain, and deformities. The condition mostly affects young men ranging in their teens to twenties. Early diagnosis is especially important to avoid cases of locked posture and/or spinal distortion. Due to the doctors involved in its discovery, the disease is sometimes called Bekhterev’s Disease or Marie-Strümpell Disease.


Definition & Facts

The term ankylosing spondylitis derives its name from two words: the verb, “ankylose,” meaning to stiffen, and the noun, “spondylitis,” meaning backbone joint inflammation. Three doctors contributed to the discovery of ankylosing spondylitis

  • Vladimir Mikhailovich Bekhterev (Russian neurologist, 1857 – 1927)
  • Pierre Marie (French neurologist, 1853 – 1940)
  • Ernst Adolf Gustav Gottfried von Strümpell (German neurologist, 1853 – 1925)

Symptoms & Complaints

There are several indications of ankylosing spondylitis including:

Pain can occur throughout any part of the back including


The cause of the disease is unknown; however, a correlation exists between a specific gene, HLA-B27 and the increased likelihood of having AS. As the percentage of individuals that have this gene increase, so does the rate of people who tend to have ankylosing spondylitis.

It is unclear what exactly triggers the disease in those who have HLA-B27, but factors such as environment may seem to be at play; different nations exhibit different statistics. For example, in the United States, 7% of the population possess HLA-B27, while only 1% develop AS. In northern Scandinavia, 24% possess the gene, while 1.8% acquire ankylosing spondylitis.

There are two genes, which are also seemingly associated with obtaining AS: ARTS-1, and IL23R. ARTS-1, plays a role in the production of the ERAP-1 protein. This protein extracts peptides (smaller fragments of other proteins) from the inside of a cell, and shows it to the immune system. If the immune system finds the cell to be viral or bacterial, then the system initiates a sequence to have the cell self-destruct.

IL23R is responsible for creating a protein that embeds into the cell membrane of immune-based cells. These antibodies target harmful bacteria and viruses, and perform actions to eliminate them from the body. Ankylosing spondylitis is associated with mutations in both IL23R and ARTS-1.

Diagnosis & Tests

A doctor may perform several tests on a patient to determine whether he/she has ankylosing spondylitis or not. A few of these tests are

  • Chest expansion measurement – The doctor may perform chest measurements; he/she will measure the chest during a full exhalation, and after a full inhalation.
  • Spinal movement – The doctor may ask the patient to rotate, bend or maneuver the spine in order to test for AS
  • Wall test – The medical professional will analyze several factors as the patient stands (or attempts to stand) straight, heels, back and head against the wall
  • Pressure test – the health care professional will check for pain in areas along the lower back and pelvic region

Though ankylosing spondylitis may not have drastic symptoms, X-rays can be done in order to determine if the patient is exhibiting the symptoms of AS. X-rays will reveal any changes in bone structure and/or formation; findings of bone obstruction appear on these tests.

A more costly method of checking for AS is by means of MRI or magnetic resonance imaging. This type of imaging hardware and software provides much more information than that pertaining to the skeletal structure. MRI’s can view fats, fluids (water, blood), and soft-tissues, especially those relating to whole organs. An MRI has the possibility to determine early signs of AS by showing signs of sacroiliac joint inflammation.

Ankylosing spondylitis can also be checked by means of blood testing. Here the doctors will check for the protein HLA-B27. Though a risk factor, the presence of this gene does not determine whether or not the patient definitely has AS.

Treatment & Therapy

Exercise, especially swimming, is an excellent way to reduce the risk of stiffness and debilitation. Exercising strengthens muscles lining the back, strengthening them to overcome stiffness and/or inflammation. There are also physical therapy and occupational treatment regimens that can aid in the remedying of AS.

NSAIDs (nonsteroidal anti-inflammatory drugs), DMARDs (disease-modifying antirheumatic drugs), as well as others are used to treat moderate to severe pain. Several biologic drugs are available for treatment of ankylosing spondylitis – biologic medicines are typically proteins, cultures, or whole organisms grown in a system, and used for medical treatment.

TNFs (tumor necrosis factors blockers) are also administered in more severe cases to reduce stiffness, pain and swelling – these drugs are normally injected intravenously near the site of inflammation. Laminectomies, or surgical removal of the lamina from the spine, are available for patients with more advanced AS. During this procedure, the back muscles are moved aside instead of cut to aid in recovery time.

Rods, bars, and screws may be used to assist in the straightening of the spine during fusion. In this case, the bones still fuse together; however, the arching, which typically results from AS, is counteracted using rods, bars and screws. The spine may be cut in a procedure known as an osteotomy. Osteotomies are used to correct the spine’s angling so the bone can heal in a proper fashion for normal functioning.

Prevention & Prophylaxis

Since the cause of AS is not completely known, it is unclear how to prevent the disease. However, keeping a healthy diet along with regular exercise help to keep the spine healthy longer. Following through on a treatment plan with a physical therapist or health care professional is also necessary to prevent the disorder from ruining one’s regular, day-to-day functions.