WHAT ARE ANKYLOSING SPONDYLITIS (AS) AND NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS (NR-AXSPA)?
Ankylosing spondylitis (ank-kih-low-sing- spon-dill-eye-tiss) and non-radiographic axial spondyloarthritis (non ray-dee-oh-gra-fick aks-ee-al spon-dill-low-arth-reye-tiss) are chronic, inflammatory diseases that primarily attack the spine.
AS and nr-axSpA can also cause pain and stiffness in other areas of the body, like:
- shoulder blades
- hips
- feet
AS and nr-axSpA are often confused with mechanical pain—the kind caused by physical strain or injury.
Axial spondyloarthritis (axSpA) is a term you might hear that refers to chronic inflammatory diseases affecting the spine. Both AS and nr-axSpA belong to this category.
It's important to understand that AS and nr-axSpA are inflammatory diseases – not symptoms of a slipped disk, a sprain or muscle strain.
Here are some ways that could help you determine whether your back pain is mechanical or inflammatory:
MECHANICAL
Usually caused by physical strain to the back (e.g., a sprain or muscle pull)
Typically recognized by pain that:
- Lasts less than 3 months
- Feels better with rest
- Can begin suddenly
INFLAMMATORY
Caused by the immune system attacking healthy tissue, resulting in inflammation in the joints of the spine
Typically recognized by pain that:
- Lasts longer than 3 months
- Feels better with exercise
- Worsens and spreads to other areas of the body over time
Talk to your doctor if you’re experiencing any of the symptoms in the table above. Only your doctor can diagnose the type of back pain you’re suffering from.
If you haven't heard of AS or nr-axSpA, you're not alone. Part of the reason is both are difficult to diagnose.
Some people who have AS or nr-axSpA experience mild back pain that comes and goes, while others have chronic pain. Over time, inflammation can lead to severe cases of ankylosing spondylitis and can cause the bones of the spine, neck, or rib cage become rigid. If bones in the rib cage fuse together, it can eventually lead to ankylosing spondylitis, and make breathing more difficult.
It is estimated that up to 40% of nr-axSpA patients will develop AS within 10 years, and that 50% of people with nr-axSpA will progress to AS within their lifetimes.
With ankylosing spondylitis, structural damage to the spinal joints is visible on an X-ray (or "radiograph").
With non-radiographic axial spondyloarthritis, there is no clear evidence of inflammation on an X-ray. However, inflammation can sometimes be detected on an MRI.
What does “ankylosing spondylitis” mean?
“Ankylosing spondylitis” comes from 2 Greek words:
- “Ankylos” meaning stiffening of a joint
- “Spondylo” meaning vertebrae (small bones in the backbone)
Ankylosing spondylitis (AS) is also known as Bechterew’s syndrome or Marie-Strumpell disease, and belongs to a family of disorders called spondyloarthropathies, spondyloarthritis, or spondylitis.
What does "non-radiographic axial spondyloarthritis" mean?
- "Non-radiographic" meaning damage to the spine is not visible on an X-ray
- "Axial" meaning related to the center part of the body or spine
- "Spondyloarthritis" meaning inflammatory condition of the spine and joints of the arms and legs
How common are AS and nr-axSpA?
Studies show that nearly 3.2 million people in the United States have either ankylosing spondylitis (AS) or non-radiographic axial spondyloarthritis (nr-axSpA).
Unlike other forms of arthritis, axSpA (AS and nr-axSpA) usually affects younger adults. Symptoms tend to start between 20 and 30 years of age years of age.
“
When my rheumatologist first mentioned that I had ankylosing spondylitis, I had to ask him, ‘What is that?’
”
Noel
Real AS patient
TAKE THE SYMPTOM QUIZ
Find out if your back or neck pain and stiffness could be ankylosing spondylitis or non-radiographic axial spondyloarthritis and then talk to your doctor about your symptoms.
EXPLORE AXSPA TREATMENTS
AS and nr-axSpA can cause symptoms in areas besides the spine—and get worse over time. Find out which treatment options are available and discuss with your doctor.