Ankylosing spondylitis (AS) is a form of arthritis that typically affects the spine, lower back, and sacroiliac joints. People with the condition have an increased risk of developing other spinal problems, such as spinal stenosis.

Spinal stenosis occurs when the spaces inside the spinal canal become narrow. This can result in nerve compression, pain, weakness, or numbness. However, not everyone with spinal stenosis experiences symptoms.

Read on to learn more about the link between ankylosing spondylitis and spinal stenosis, as well as how to treat and prevent spinal stenosis.

A doctor holding up an X-ray to look for signs of spinal stenosis in someone with ankylosing spondylitis.Share on Pinterest
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The spinal canal is located in the center of the spine and contains the nerve roots and spinal cord. If the spinal canal becomes narrower, it can compress these structures. This condition is known as spinal stenosis.

Spinal stenosis can cause symptoms such as pain, weakness, and numbness. The symptoms may vary depending on which area of the person’s spine the compression affects.

A person can have either congenital or acquired spinal stenosis. Congenital spinal stenosis means that the person has had the condition from birth. Only 9% of spinal stenosis cases are congenital. Acquired spinal stenosis, which is more common, occurs at a later age — typically after the age of 50 years — and is often due to trauma or degenerative changes.

AS is one of a number of conditions that can increase a person’s risk of developing spinal stenosis.

AS causes inflammation that can damage and wear away bone in the spine. As the body replaces this bone, it can create too much, causing joints to fuse and possibly causing the spinal canal to narrow.

The symptoms of spinal stenosis include:

  • neck pain
  • back pain
  • numbness in the arms or legs
  • weakness in the arms or legs
  • cramping
  • pain going down one leg
  • foot problems

If a person suffers from pain due to spinal stenosis, this pain may worsen when they walk up or down a hill, ramp, or steps. A person can often relieve the pain by sitting down or leaning over.

People who experience more severe spinal stenosis may have problems with the following bodily functions:

  • bowel
  • bladder
  • sexual

Not everyone with a narrowed spinal canal experiences symptoms. If no symptoms occur, the person may not require any treatment.

To diagnose spinal stenosis, a doctor will first ask questions about the person’s medical history and symptoms. They will then perform a physical examination. During the exam, the doctor may check:

  • the person’s ability to move and walk
  • how the pain changes when they bend their spine backward and forward
  • neurological function, including sensation, muscle strength, and reflexes
  • balance

If a doctor suspects that the person’s symptoms are the result of spinal stenosis, they may order imaging tests to check whether the person’s spinal canal is narrow. The tests may include:

In some cases, a doctor may inject a liquid dye into a person’s spinal column before the imaging test. This is to help them see the spinal column more clearly.

There are various treatment options for spinal stenosis.

Nonsurgical treatments

Common nonsurgical treatments for spinal stenosis include:

  • Physical therapy: The American Physical Therapy Association (APTA) states that physical therapists can improve a person’s quality of life through special exercises, hands-on care, and patient education. A person with spinal stenosis can use physical therapy to maintain the motion of their spine, strengthen their abdominal and back muscles, and build endurance. In doing so, they can help stabilize the spine.
  • Back brace: A person may choose to wear a back brace to provide more support for their spine. This can help them regain mobility. However, it is not suitable for long-term use, as wearing it for prolonged sessions over a long period can cause the paraspinal muscles to become weak, which will lead to other problems.
  • Manipulation of the spine: A healthcare professional can use their hands to adjust and massage the person’s back. This can include manipulating the spine and the back muscles.
  • Acupuncture: This form of complementary therapy involves a practitioner inserting very thin needles into the body at certain pressure points. It may help relieve pain.

Not all of these options may be suitable for people with AS. It is important to let healthcare professionals know about co-existing conditions so that they can make informed decisions regarding the treatment approach. Doctors and physical therapists may be able to adjust the person’s treatment plan to address and accommodate both conditions.

Medications

A doctor may prescribe medications to help treat spinal stenosis pain. The options include:

If a person is already taking medication to treat AS, they should let the doctor know before taking medication for spinal stenosis. AS medications may interact with some spinal stenosis medications.

Surgery

In some cases, a doctor may recommend surgery. This may be an option if:

  • nonsurgical treatments do not work
  • the person has numbness or weakness that impairs their ability to walk
  • the person’s spinal stenosis affects their bowel or bladder function, or there is other neurological involvement

A surgeon will take multiple factors into account before deciding on whether surgery is the correct option. They will consider:

  • the effect that nonsurgical treatments have had on the person’s symptoms
  • the amount of pain the person feels
  • the person’s overall health, including any other underlying conditions

Possible surgeries to treat spinal stenosis include:

  • Laminectomy: This procedure involves removing the bony spurs and the bone walls of the vertebrae, which can open up the spinal canal and reduce the pressure on the nerves.
  • Spinal fusion: This surgical procedure helps treat a number of age-related spinal changes. During the procedure, a surgeon will join or fuse two or more vertebrae that have slipped from their normal position.
  • Removing and repairing areas of the spine: A surgeon may also suggest removing or repairing certain parts of the spine. This can help relieve pressure and may ease symptoms such as leg pain and difficulty walking. If a person has badly damaged nerves, some of the numbness may remain after surgery.

It is important to note that because AS involves the formation of new bone, it can affect the long-term outcomes of these surgical procedures.

There is no guaranteed way for people with AS to prevent spinal stenosis. However, by effectively managing AS, a person may be able to reduce excess bone growth inside the spine. This, in turn, may reduce the risk of spinal stenosis.

The Arthritis Foundation recommends early and aggressive treatment for AS to prevent bone damage. An effective treatment approach will likely include the following elements:

  • Medications: Medication can reduce inflammation and the damage it causes to bones. This may stop the new bone from growing and so prevent a number of AS complications.
  • Diet: An anti-inflammatory diet may help reduce the impact of AS. This diet involves limiting inflammatory foods, such as saturated fat and sugar, and focusing on anti-inflammatory alternatives, such as unsaturated fats, fruits and vegetables, and lean protein.
  • Exercise: This can help with stiffness, range of motion, posture, and flexibility. Physical therapy can also help with stretching the muscles and keeping them strong.
  • Assistive devices: These devices protect the joints from strain during daily activities. Some examples include braces, splints, and raised seats to make sitting down easier.
  • Stopping smoking: Smoking increases inflammation and can speed up joint damage. If a person does smoke, they can find help with quitting at smokefree.gov.

Spinal stenosis occurs when the gaps inside the spine narrow, compressing the nerves or spinal cord. Having AS elevates the risk of getting spinal stenosis, as the excess bone that can grow as a result of damage can take up space inside the spine.

The symptoms of spinal stenosis include neck and back pain, numbness or weakness in the arms or legs, cramping, and pain going down one leg.