Spinal stenosis is a condition that causes compression of the nerves in the spine.
It can lead to a range of symptoms, including pain, weakness, and numbness in different parts of the body.
This article outlines the causes and symptoms of spinal stenosis, along with information on diagnosis and treatment.
Spinal stenosis occurs when the gaps between the vertebrae, or spinal bones, narrow.
This narrowing compresses the spinal canal, causing it to pinch on the spinal cord and nerve roots. It may result in pain, weakness, or numbness, often in the legs and feet.
The vertebrae are 33 bones that connect to form the spinal canal. The spinal canal contains the spinal cord, which extends from the base of the skull down through the lower back.
At its base, the spinal cord separates out into a bundle of nerve roots. These nerve roots branch out of the spinal canal through gaps in the vertebrae.
Spinal stenosis may be congenital or acquired. Congenital spinal stenosis is present from birth. It is usually the result of having a small spinal canal.
Acquired spinal stenosis develops either as a result of age-related changes to the spine or as a symptom of another medical condition.
The following factors increase the risk of developing spinal stenosis:
- having scoliosis, which is a sideways curvature of the spine
- having previously injured the spine or received spinal surgery
- having excess fluoride or calcium in the body
Osteoarthritis is the most common cause of acquired spinal stenosis. Osteoarthritis is a degenerative form of arthritis that can cause changes to the spine and surrounding structures as a person ages.
Some of these changes cause compression of the spinal canal. Examples include:
- the development of bone growths called spurs on the vertebrae
- the degeneration and inflammation of the joints between the vertebrae
- the thickening of the ligaments that support the spine
The following types of arthritis may also cause spinal stenosis:
Other medical conditions that can cause spinal stenosis include:
- a tumor in the spinal cord or other part of the spine
- scoliosis
People with spinal stenosis may experience the following symptoms in the legs or feet:
- severe pain
- numbness
- weakness
- cramps
These symptoms may begin slowly and get worse over time.
In severe cases, a person may experience partial or complete leg paralysis. This is a medical emergency, and the person should call 911 or the local emergency services immediately.
Some people develop a type of spinal stenosis called cauda equine syndrome (CES).
CES affects the nerve roots at the base of the spine. It is a serious condition that can result in permanent paralysis and incontinence if a person goes without treatment.
Symptoms of CES include:
- sciatic nerve pain, which travels down one leg
- weakness in one or both legs
- difficulty walking
- abnormal bladder or bowel function
- loss of sensation across the genitals, anus, and inner thighs
- loss of sexual function
To diagnose spinal stenosis, a doctor or rheumatologist will ask a person about their symptoms and medical history. They will also perform a physical examination.
They may then order the following tests to confirm the diagnosis:
- an X-ray of the spine, which can detect osteoarthritic changes
- an MRI or CT scan, which can detect changes to the tissues in and around the spinal canal
- a myelogram test, which involves injecting dye into the spinal column to differentiate between various types of tissue
- an electromyogram, which uses an electrode to measure electrical activity in the nerves and muscles
A doctor may also request other tests, such as blood tests, to rule out different causes of a person’s symptoms.
Spinal stenosis can worsen gradually over time. Although there is no cure, a combination of treatments can help stabilize the condition and alleviate some of the symptoms.
Treatment options include:
Medication
Pain relief medications, such as acetaminophen and nonsteroidal anti-inflammatory drugs, are available over the counter.
For more severe symptoms, a doctor may prescribe other drugs, such as:
- stronger pain medications, such as opioids
- muscle relaxants to alleviate painful muscle spasms and cramps
- steroid injections to reduce inflammation around the spinal cord
Surgery
In some cases, a person may need to undergo spinal decompression surgery to alleviate severe or worsening symptoms.
Spinal decompression surgery involves removing bony growths and other inflamed tissues from the spinal canal, freeing up space for the nerves and spinal cord.
A surgeon may perform spinal decompression as an open spine surgery or as a minimally invasive procedure, depending on the situation.
The minimally invasive option involves a doctor guiding a tiny camera and other surgical instruments through a small incision. This method causes less damage to the muscles and soft tissues, and it carries a lower risk of infection.
Getting regular exercise or trying physical therapy can help strengthen muscles in the back, arms, and legs, leading to improved flexibility, balance, and mobility.
The American College of Rheumatology recommend a minimum of three 30-minute exercise sessions per week for people with spinal stenosis.
These sessions should incorporate flexion-based exercises, which involve bending the lower back forward.
Once a person has strengthened their back, they may incorporate other gentle activities, such as walking or swimming, into their routine.
Performing the following back exercises can help increase the space between the vertebrae, reducing compression of the spinal canal:
Knee to chest
To do this stretch:
- begin by lying face-up on the floor with both knees bent
- slowly draw the right knee toward the chest and clasp it loosely with both hands
- gently draw the knee back in toward the chest 10 times
- switch and do the same with the other leg
Knee hug
To do this stretch:
- begin by lying face-up on the floor with the knees bent
- draw both knees toward the chest and pull them closer with both hands
- slowly release the knees and return to the starting position
- repeat 10 times
Draw-in maneuver
To do this exercise:
- begin by lying face-up on the floor with the knees bent
- push the lower back toward the floor while pulling in the lower abdominal muscles
- avoid moving the hips
- hold for 5 seconds and breathe normally, then relax
- repeat 10 times
Lower back rotational stretch
To do this stretch:
- begin by lying face-up on the floor with both knees bent
- pull the abdominal muscles in
- gently lean both knees over to the right-hand side as far as feels comfortable, then return them to the center
- lean both knees over to the left-hand side as far as feels comfortable, then return them to the center
- repeat 10 times
People with symptoms of spinal stenosis should talk to their doctor. Diagnostic tests will be necessary to confirm the diagnosis and rule out other medical conditions.
Spinal stenosis is a condition that may worsen over time. Although there is no cure, exercise may help strengthen the back and alleviate compression of the spinal canal.
The current medical treatments focus on relieving pain and inflammation. In severe cases, a person may need surgery to decompress the spinal canal.