What is foraminal stenosis?

Foraminal stenosis is the narrowing or tightening of the openings between the bones in your spine. These small openings are called the foramen. Foraminal stenosis is a specific type of spinal stenosis.

Nerves pass though the foramen from your spinal cord out to the rest of your body. When the foramen close in, the nerve roots passing through them can be pinched. A pinched nerve can lead to radiculopathy — or pain, numbness, and weakness in the part of the body the nerve serves.

Foraminal stenosis and pinched nerves are common. In fact, nearly half of all middle-aged and older people have some kind of spinal stenosis and pinched nerves. But not everyone with foraminal stenosis will experience symptoms. Some people may have symptoms that come and go.

You can’t prevent foraminal stenosis, but staying physically active and maintaining a healthy weight can help reduce your risk. Using good posture and technique when sitting, playing sports, exercising, and lifting heavy objects can also help prevent injury to your back. Injuries can lead to stenosis and pinched nerves.

Keep reading to learn about the symptoms, treatment options, and more.

Symptoms of pinched nerves due to foraminal stenosis vary depending on which part of your spine is affected.

Cervical stenosis develops when the foramen of your neck narrow. Pinched nerves in your neck can cause a sharp or burning pain that starts in the neck and travels down your shoulder and arm. Your arm and hand may feel weak and numb with “pins and needles.”

Thoracic stenosis develops when the foramen in the upper portion of your back narrow. Pinched nerve roots in this part of your back can cause pain and numbness that wrap around to the front of your body. This is the least common area to be affected by foraminal stenosis.

Lumbar stenosis develops when the foramen of your low back narrow. The lower back is the section of your spine most likely to be affected by foraminal stenosis. This can be felt as pain, tingling, numbness, and weakness in the buttock, leg, and sometimes the foot. Sciatica is a term you may have heard for this type of pain.

Your pain may worsen with certain activities, like bending, twisting, reaching, coughing, or sneezing.

You’re more likely to develop foraminal stenosis and pinched nerves as you age. Arthritis and the wear and tear of daily living often lead to changes in your spine that narrow the foramen. But injury can cause stenosis as well, especially in younger people.

For example, one cause of foraminal stenosis is a bulging or herniated disk. These cushioning disks between your spinal bones can slip out of place or become damaged. The bulging disk presses on the foramen and nerve root. This is most likely to happen in your lower back.

Bone growths in and around your foramen can also pinch the nerves running through. Bone spurs form due to injury or degenerative conditions like osteoarthritis.

Other less common causes of foraminal stenosis include:

  • enlargement of ligaments around the spine
  • spondylolisthesis
  • cysts or tumors
  • bone disease, such as Paget’s disease
  • genetic conditions, such as dwarfism

If you have pain that radiates down your arm or leg or feelings of numbness that last for several days, you should see with your doctor.

At your appointment, your doctor will start with a physical exam. They’ll check your movement, muscle strength, level of pain and numbness, and reflexes.

Your doctor may order some imaging scans and other tests to confirm the diagnosis:

  • X-rays can be used to see alignment of the bones of your spine and narrowing of the foramen.
  • MRI scans can detect damage in the soft tissues, such as ligaments and disks.
  • CT scans can show more detail than X-rays, allowing your doctor to see bone spurs near the foramen.
  • Electromyography and nerve conduction studies are done together to see if your nerve is working properly. These tests help your doctor figure out if your symptoms are caused by pressure on spinal nerve roots or by another condition.
  • Bone scans can detect arthritis, fractures, infections, and tumors.

Grading

Your doctor or the radiologist who reads your MRIs may grade the level of narrowing of your foramen.

  • grade 0 = no foraminal stenosis
  • grade 1 = mild stenosis with no evidence of physical changes in the nerve root
  • grade 2 = moderate stenosis with no physical changes in the nerve root
  • grade 3 = severe foraminal stenosis showing nerve root collapse

Depending on the cause and severity of your foraminal stenosis and pinched nerves, several treatments are available to ease your discomfort.

In many cases, pinched nerves — especially in the neck — will get better with no treatment other than stretching, activity modification, and pain-relieving medicines.

Activity modification

If you have the radiating pain, numbness, and weakness of a pinched nerve, you may want to rest for a few days. But don’t be inactive for too long, or your symptoms may worsen. You should avoid movements that cause you sharp pain, but you shouldn’t be motionless. Using cold packs for the first few days, followed by warm packs or a heating pad, may help ease your pain.

Physical therapy

Stretches and special exercises can be used to stabilize your spine, improve range of motion, and open up the space for your nerve roots to pass. Strengthening the muscles that support your spine can prevent further damage. Losing weight can also take pressure off of your spine and nerve roots.

Orthotics

If you have a pinched nerve in your neck, your doctor may recommend you wear a neck brace or soft cervical collar. It will limit your movement and let your neck muscles rest.

It should be worn for only a short time because if you wear it for too long, the muscles in your neck may weaken. Your doctor will provide you with specifics about when to wear it and for how long.

Doctors generally don’t advise wearing a back brace of any kind for pinched nerves in the low back.

Medications

Different types of medicines can be used to ease your pain:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs): Medicines like aspirin (Bufferin), ibuprofen (Advil), and naproxen (Aleve), may reduce inflammation and provide pain relief.
  • Steroids: Oral corticosteroids, like prednisone (Deltasone), may help ease pain by reducing inflammation around the irritated nerve. Steroids can also be injected near the affected nerve to relieve inflammation and pain.
  • Narcotics: If your pain is severe and other treatments haven’t worked, your doctor may prescribe narcotic pain relievers. They’re usually used for only a short time.

Surgery

If conservative treatments don’t relieve your symptoms, you and your doctor may consider surgery. The type of surgery will depend on the location of the stenosis and what’s causing it. If a herniated disk is pinching your nerve root, then surgery to remove the bulging disk may be the solution.

A minimally invasive procedure called foraminotomy may be another option. It enlarges the area that the nerve passes through by removing obstructions, like bone spurs, from the foramen.

Sometimes foraminal stenosis can be accompanied by stenosis of the spinal column itself. When the spinal cord is compressed, the symptoms may be more severe than when the nerve roots are pinched.

These symptoms can include:

  • clumsiness
  • trouble using your hands
  • difficulty walking
  • weakness

The vast majority of people with foraminal stenosis will find relief with at-home treatment. Surgery is rarely necessary. Sometimes, even after your symptoms have resolved for weeks or years, they may come back. Follow your doctor’s instructions regarding physical therapy and activity modifications, and your pinched nerve pain will probably be a thing of the past.