What Are the Complications of Ankylosing Spondylitis?

Health Line

09-07-2025

Key takeaways
Ankylosing spondylitis can lead to long-term joint pain and damage, potentially affecting the spine, hips, jaw, chest, neck, ribs, knees, heels, and fingers.
The condition may cause neurological issues like cauda equina syndrome, resulting in symptoms such as sciatica, incontinence, and pain in the buttocks and legs.
Untreated ankylosing spondylitis can lead to complications such as chronic fatigue, spinal fusion, eye problems, and cardiovascular disease, highlighting the importance of early diagnosis and management.
Ankylosing spondylitis (AS) is a type of arthritis that affects your spine, causing inflammation of the sacroiliac joints in your pelvis. These joints connect the sacrum bone in the lower part of your spine to your pelvis.
The most common symptoms of AS include pain and stiffness in your lower back, which can reduce your mobility and make daily activities more difficult.
Several lifestyle strategies and medical treatments can help you manage AS, but the condition may lead to complications that could affect more than just your mobility.
Keep reading to learn more about the possible complications of AS.
Joint pain and damage
The most common complication of AS is chronic (long-term) joint pain and damage to your spine.
You might also experience pain, stiffness, and damage to other joints in your body or in areas where ligaments, tendons, and cartilage attach to bones. These areas may include your:
hips
jaw
chest
neck
ribs
knees
heels
fingers
Inflammation may spread to the joints and cartilage in your rib cage. Over time, the bones may fuse, making it difficult for your chest to expand and causing pain when you breathe.
Fatigue
Chronic fatigue is one of the most common symptoms of AS, after joint pain and stiffness. Fatigue is more than just being tired. It often includes a lack of energy, severe tiredness, or brain fog.
Many factors related to AS may cause fatigue, including:
loss of sleep due to pain or discomfort
anemia
muscle weakness, which means your body must work harder to move around
depression, other mental health conditions, and neurological changes
the use of certain medications to treat arthritis
A doctor may suggest more than one type of treatment to address fatigue.
Eye problems
Inflammation in one or both of your eyes is called iritis or uveitis.
According to the Spondylitis Association of America (SAA), about half of all people with AS will experience iritis at least once in their lifetime.
It's important to get immediate medical treatment if you have AS and experience any of the following eye symptoms:
redness
swelling
pain
blurry vision
If left untreated, iritis may lead to permanent eye damage.
»More on this: What's the link between AS and eye inflammation?
Gastrointestinal problems
With AS, it's possible that you'll experience inflammation of your digestive tract, either before or after you begin to experience joint symptoms.
According to the SAA, 1 in 2 people with AS experience some gastrointestinal inflammation. This can result in stomach pain, diarrhea, and digestive problems.
Up to 1 in 2 people with AS may also experience inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease.
Fused spine
As the joints in your spine become inflamed and damaged, new bone can form between your vertebrae (spinal bones). Over time, this may cause ankylosis, which is the fusion of vertebrae. As a result of this, you may have more difficulty bending and twisting.
If you don't maintain a neutral ('good') posture, a fused spine can result in a long-term stooped posture.
A healthcare professional may recommend focused exercises, swimming, or water-based aerobics to help maintain your mobility and prevent a fused spine.
In severe cases, they may also recommend surgery. According to the Arthritis Foundation, spinal fusion surgery can help treat spinal fusion in 4 out of 5 cases.
However, surgery may sometimes cause an increase in reactive bone formation, which can worsen symptoms rather than lessen them. It's important to work with a healthcare team that includes an orthopedic surgeon and a rheumatologist to decide whether surgery is a good option for you.
Heart and lung problems
Inflammation can sometimes spread to the aorta, the biggest artery in your body. Inflammation can prevent the aorta from functioning properly, leading to cardiovascular problems.
Heart problems associated with AS may include:
According to the SAA, up to 1 in 10 people with AS experience cardiovascular problems associated with inflammation.
People with AS also have an increased risk of developing lung and breathing complications.
For instance, interstitial lung disease may occur as a result of damage to lung tissue. And restrictive pulmonary disease may occur if the bones in your rib cage fuse together, which can make it difficult for your chest to expand and can cause pain with breathing.
When to connect with a doctor
If you experience back pain, stiffness, or other symptoms of AS, consider speaking with a healthcare professional.
They can assess your symptoms and perform several tests to determine the underlying cause. These tests may include:
blood tests for inflammation and anemia
X-ray
MRI
ultrasound
genetic tests
Early diagnosis and treatment can help you manage your symptoms and reduce the risk of complications.
Frequently asked questions
What is the most common complication of ankylosing spondylitis?
The most common complications of ankylosing spondylitis are reduced mobility (as a result of joint pain and stiffness) and chronic fatigue. Other common complications include eye inflammation and gastrointestinal problems, such as IBD.
The most common complications of ankylosing spondylitis are reduced mobility (as a result of joint pain and stiffness) and chronic fatigue. Other common complications include eye inflammation and gastrointestinal problems, such as IBD.
What is the most serious complication of spondylosis?
In rare cases, spondylosis may lead to complications that require medical attention, including cauda equina syndrome, bone fractures, and spondylodiscitis (spinal infection).
In rare cases, spondylosis may lead to complications that require medical attention, including cauda equina syndrome, bone fractures, and spondylodiscitis (spinal infection).
Will I end up in a wheelchair with ankylosing spondylitis?
You may need to use a wheelchair if you have severe ankylosing spondylitis because the condition may reduce your physical mobility and function, affecting your ability to walk.
That said, a treatment plan that includes exercise, medication, and lifestyle changes can greatly reduce the likelihood that you'll need to use a wheelchair for ankylosing spondylitis.
You may need to use a wheelchair if you have severe ankylosing spondylitis because the condition may reduce your physical mobility and function, affecting your ability to walk.
That said, a treatment plan that includes exercise, medication, and lifestyle changes can greatly reduce the likelihood that you'll need to use a wheelchair for ankylosing spondylitis.