Key takeaways

  • Ankylosing spondylitis (AS) is a type of arthritis that causes inflammation in the spine, leading to stiffness and potential vertebral fusion. Spondylolisthesis occurs when a vertebra slips out of alignment, creating spinal instability.
  • Both conditions can cause lower back pain, but AS may also affect other joints and cause systemic symptoms like fatigue and loss of appetite. Spondylolisthesis may cause numbness or weakness in the legs.
  • Treatment for both conditions may include physical therapy to strengthen back muscles and improve flexibility, nonsteroidal anti-inflammatory drugs (NSAIDs) for pain, and surgery in severe cases.

Inflammation due to ankylosing spondylitis (AS) can stiffen the joints in the spine and, in some cases, cause the vertebrae to fuse. When the vertebrae fuse, the spine can become rigid and inflexible.

Spondylolisthesis can cause the spine to become unstable. It can also increase the chance of a person developing bone spurs or arthritis.

Read on to learn more about AS and spondylolisthesis. This article looks at symptoms, causes, treatment options, and more.

AS and spondylolisthesis can both cause lower back pain. However, some symptoms can help differentiate the two conditions.

Symptoms of AS

AS causes inflammation in the spine. This inflammation can cause pain and swelling.

Medical professionals refer to AS as a systemic condition, which means it can also affect other body parts and organs.

Common symptoms of AS include:

AS may also cause a person to develop pain and swelling in their:

  • toes
  • heels
  • ankles
  • knees
  • rib cage
  • upper spine
  • shoulders
  • neck

Symptoms of spondylolisthesis

Spondylolisthesis may cause lower back pain. If the condition affects the higher part of a person’s spine, they may develop neck pain.

Back pain may become worse if a person flexes or extends their back. Pain may improve when a person lies on their back facing upward.

Other symptoms of spondylolisthesis can include:

  • buttock pain
  • numbness or weakness in the legs
  • problems walking

The exact cause of AS is unclear. Spondylolisthesis has two possible causes.

Causes of AS

While the exact cause of AS is unclear, the condition may develop due to specific genetic and environmental factors.

People with the HLA-B27 gene are at an increased risk of developing AS. Around 90% of people with AS have this gene, compared with 8% of people in the general population.

A person with this gene may develop AS if they come into contact with certain triggers. Possible triggers include viruses and bacteria.

Causes of spondylolisthesis

There are two main types of spondylolisthesis: degenerative spondylolisthesis and spondylolytic spondylolisthesis.

Degenerative spondylolisthesis occurs due to general wear and tear over time. Changes in the spine develop gradually and can cause the disks between the vertebrae to weaken and lose height.

Spondylolytic spondylolisthesis can occur when a stress fracture (crack) develops in a vertebra. General degeneration of the disks between the vertebrae can then cause the cracked vertebrae to slip forward, causing spondylolytic spondylolisthesis.

Medical professionals will likely use the same steps to diagnose AS and spondylolisthesis.

They may begin by taking a person’s medical history and carrying out a physical exam.

During the physical exam, a doctor may examine the person’s back and push on certain areas to see if the person feels pain. The doctor may also look at the person’s joints and observe how they move and bend in different directions.

A doctor may then use a number of imaging studies to look at the structure of a person’s spine. These imaging tests can include:

  • X-ray: An X-ray scan uses radiation to create images of the inside of the body. An X-ray can show joint changes and whether the bones in the spine are in the correct location.
  • MRI: MRI scans use a powerful magnet to create cross-sectional images of structures inside the body. These scans can help show detailed images of the joints in the spine. They can also help show soft tissues in the spine, such as:
    • muscles
    • disks
    • nerves
    • the spinal cord

Blood tests to check for the HLA-B27 gene may also help.

Doctors may use similar treatment methods to treat AS and spondylolisthesis.

Physical therapy is a possible treatment for AS. Doctors may also suggest physical therapy to treat spondylolisthesis.

Physical therapy can help:

  • relieve pain
  • strengthen the muscles in the back and neck
  • strengthen the abdominal muscles to offer extra support to the back
  • improve a person’s posture
  • improve flexibility in joints

Doctors may also recommend medications to help treat pain and inflammation associated with AS and spondylolisthesis. Nonsteroidal anti-inflammatory drugs (NSAIDs) can help manage pain related to either condition.

Other medications for AS include:

  • biologics
  • Janus kinase (JAK) inhibitors
  • corticosteroids

In severe cases, or if symptoms do not respond to other treatments, a doctor may recommend surgery to treat AS and spondylolisthesis.

Ankylosing spondylitis (AS) is a type of arthritis that causes inflammation of the spinal joints, leading to stiffness and potential vertebral fusion. Common symptoms include lower back pain, buttock pain, fatigue, and swelling in various joints.

Spondylolisthesis occurs when a vertebra slips out of alignment. It typically affects the lumbar spine and can cause pain, numbness, and instability.

When diagnosing AS and spondylolisthesis, a doctor will check a person’s medical history and carry out a physical exam. They may also use imaging studies for a closer look at the spine.

Some treatments can help with both AS and spondylolisthesis. These include physical therapy and certain medications. In severe cases, a person may undergo surgery.