Ankylosing Spondylitis: Symptoms, Causes, and Treatments

Ankylosing spondylitis (AS) is a type of arthritis that primarily affects the low back.

AS symptoms can have a wide range of effects that includes mild soreness that comes and goes to severe back pain that physically restricts the flexibility of the spine.

In this article, we'll cover what exactly is ankylosing spondylitis, its symptoms, causes and treatment options. You may use the table of contents below to take you to the exact section you're looking for. 

What is Ankylosing Spondylitis?


Ankylosing spondylitis (AS), also called Bechterew's disease, is a chronic inflammatory condition that primarily affects the lower back area, where the back joins with the pelvis.

The inflammation affects the joints and ligaments, often comes and goes in periods of flares and remissions.

This condition often gradually worsens over time, causing a higher degree of pain and immobility.

Ankylosing spondylitis can lead to permanent deformity, causing a stooped-over appearance that makes walking and even breathing more difficult.

Symptoms often appear before middle age, making this chronic condition something that someone has to continually live with.

Causes of Ankylosing Spondylitis

what causes ankylosing spondylitis

The cause of AS is not currently known by the medical community.

Research indicates that people with a gene mutation of the human leukocyte antigen-B gene (HLA-B) called HLA-B27 are at a much higher risk of developing this condition.

However, not everyone with the HLA-B27 gene actually develops the disease, and people without the HLA-B27 gene can still get it.

Ankylosing spondylitis is known to be an autoimmune disease in which the body’s own immune system attacks parts of the body.

Over time, inflammation can fuse the joints in the spine together, creating permanent, even irreversible, stiffness.


The symptoms of ankylosing spondylitis are primarily caused by either the inflammation that occurs with the disease or when joints become permanently fused together.

Permanent joint changes generally occur in later stages, indicating that the condition has progressed to a more severe state.

Symptoms of ankylosing spondylitis include:

  • Pain or stiffness in the lower back
  • Hard time bending your lower back
  • Loss of appetite
  • Warmth in the low back
  • Vision problems like eye swelling or redness
  • Abdominal pain
  • Stomach/bowel problems, like Crohn’s disease
  • Neck pain
  • Fatigue
  • Skin rash, like Psoriasis
  • Difficulty breathing
  • Pain or stiffness in the hips or shoulders

Everyone's symptoms will vary, but generally speaking, the primary symptom is pain and stiffness of the lower back.

lower back pain from AS


Unfortunately, there are many complications that are connected with ankylosing spondylitis.

Some of the complications are directly connected to the changes that the condition can cause, while others are more connected with the underlying inflammation associated with the disease.

Complications can include:

Uveitis (inflammation of the eye) - This condition is a common complication of ankylosing spondylitis and can lead to eye inflammation that could permanently affect your vision. If you have blurred vision, inflammation of the eye, or pain in your eye, you should immediately see a doctor.

Fractures - Vertebrae can become weak as inflammation develops. This makes them more prone to compression fractures, a type of fracture in which the pressure on the bone causes it to crumble. Vertebral compression fractures can cause symptoms of AS to become worse.

Posture changes - As inflammation causes changes to the vertebrae, these bones in your spine can fuse together. Fractures can accelerate this process. When bones in the spine fuse together, they cause the spine to become deformed. This leads to a permanent stooped posture that can lead to other health problems.

Heart problems - Underlying inflammation that causes ankylosing spondylitis can also cause inflammation of the heart and of the aorta, the main artery leading out of the heart. The stooped posture that this disease can cause can create additional pressure on the internal organs in the chest, further worsening cardiovascular problems.

Having one of these conditions does not necessarily mean that someone will develop ankylosing spondylitis.

possible complications of AS

Because the cause of ankylosing spondylitis is not fully understood, the risk factors are not well understood either.

Currently, the known risk factors include:

Risk Factor





Presence of the HLA-B27 gene



Family History

Family history of ankylosing spondylitis


While there's no cure for AS, a diagnosis of ankylosing spondylitis primarily depends on a history of your symptoms and imaging.

Your doctor will generally ask questions about your symptoms to see if what you're experiencing is develop an impression of if they fit with ankylosing spondylitis or other conditions.

Subsequently, you may be asked to follow up with imaging studies (CT or MRI) of your back.

In addition, your doctor or rheumatologist will often order additional testing, such as a blood test to check for the presence of the HLA-B27 gene. 

The presence of this gene is not a conclusive indicator either way but it helps provide your doctor with an additional piece of information that can support their diagnosis.

Treatment Options

exercise to alleviate AS

With treatment, the symptoms of ankylosing spondylitis can be controlled and progressive deterioration can be slowed.

Most treatments focus on reducing inflammation, maintaining function, and repairing any damage that has occurred.

Exercise is an important part of treatment and an essential part of helping to maintain function and comfort, as it helps to maintain flexibility and function of the lower spine.

This reduces stiffness and could help to reduce the likelihood that vertebrae will fuse together.

In addition, there are several different medications that can be used to improve pain and reduce inflammation, like:

  1. Non-steroidal anti-inflammatory drugs (NSAIDs) - NSAIDS like ibuprofen and naproxen offer a way to manage both pain and inflammation simultaneously.
  2. Corticosteroids - Steroids offer a stronger anti-inflammatory effect than NSAIDs, but carry long-term side effects that can be undesirable. These medicines are typically not used long-term unless the benefits outweigh the potential downsides.
  3. Disease-modifying anti-rheumatic drugs (DMARDs) - This class of drugs uses strong medicines to reduce inflammation and suppress damage caused by autoimmune diseases. While effective, they have several serious potential side effects that must be considered.

In severe cases, especially when there is a risk of vertebrae fusing together or when they already have, surgery may be necessary to help restore posture and avoid further stress and damage to the spine.

Ultimately, the best treatment for ankylosing spondylitis can only be determined by an experienced rheumatologist who specializes in treating them.

At Southwest Florida Rheumatology, we have extensive experience with how to effectively manage ankylosing spondylitis.

We invite you to contact us today to start the process of getting the help you need.

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