Osteoarthritis of the spine usually develops slowly as people age, and for some people, it is accompanied by a condition called spinal stenosis. People who have spinal stenosis may notice tingling, weakness, numbness, and/or pain that radiates down an arm or leg.
- Stenosis is a medical term that means the abnormal narrowing of a body channel. (A familiar example is the narrowing of a channel in the wrist called the carpal tunnel, which can lead to carpal tunnel syndrome.)
- Spinal stenosis is the narrowing of any bony openings in the spine through which the spinal cord or spinal nerves travel.
Spinal stenosis puts pressure on the spinal cord or spinal nerves, which can cause symptoms.
Where symptoms are felt depends on where the stenosis occurs:
- Cervical spinal stenosis occurs in the neck, and it can cause symptoms in the shoulders, arms, and hands.
- Lumbar spinal stenosis occurs in the lower back, and it can cause symptoms in the buttocks, legs, and feet.
It is uncommon for stenosis to occur in the middle section of the spine, called the thoracic spine.
How Stenosis Occurs in the Spine
Extending from the left and right of the spinal cord are 31 sets of nerves that travel to the torso, arms, and legs. Almost all of these nerves must travel through small openings (or channels) located between the spine’s vertebrae.
These small openings, called neuro-foramen, can narrow as the result of osteoarthritis. Spinal osteoarthritis causes:
- The breakdown of the cartilage at the joints between two or more vertebrae
- The development of bone spurs (osteophytes) on vertebrae
As the small openings between two vertebrae narrow, one or a pair of nerves can get pinched or squeezed. This pressure can cause pain or other symptoms.
When stenosis is not caused by osteoarthritis
Spinal stenosis is not always caused by spinal osteoarthritis. For example:
- Sometimes spinal osteoarthritis and spinal stenosis develop in tandem, with another underlying cause.
- Spinal stenosis can develop without osteoarthritis because of another spine condition, such as a collapsed vertebral disc or an inherited spine abnormality.
A physician can help diagnose the underlying cause of spinal stenosis.
Symptoms of Spinal Stenosis
People who have spinal stenosis might experience one or more of the following:
- Radiating pain
If myelopathy is involved, extensive neurological symptoms may also develop.
The onset and development of symptoms varies greatly. Symptoms that are most typical include:
- Gradual development
- Come and go (as opposed to being nonstop)
- Occur during certain activities, such as walking (lumbar stenosis) or biking while holding the head upright (neck stenosis)
- Are relieved by sitting, lying down, and/or bending forward slightly at the waist
Symptoms depend on many factors, including the severity and the location of the stenosis. For example, a person with mild lumbar stenosis may feel minor pain and tingling in the legs after spending an extended period of time standing and walking. In contrast, a person with severe neck stenosis may feel chronic, intermittent pain, weakness, and numbness in the arms and hands.
Diagnosing and Treating Spinal Stenosis
A doctor must rule out other possible causes for the patient’s symptoms. If stenosis is determined to be the cause of the symptoms, the doctor will also try to determine its location and underlying cause.
Diagnosis requires a patient interview, a physical exam, and possibly medical imaging. In some cases, a physician will order lab tests to help rule out systemic conditions, such as ankylosing spondylitis and vitamin deficiencies.
Doctors usually recommend patients first try one or more nonsurgical treatments for spinal stenosis. Nonsurgical treatments include:
- Exercise to strengthen the muscles that support the joints of the spine
- Activity modification to avoid movements that exacerbate symptoms
- Epidural injection to numb the affected area
- Medication to ease pain
If nonsurgical treatments do not work, or if the spinal stenosis symptoms are severe and disabling, a doctor might recommend surgery. Surgery may also be recommended sooner if the stenosis affects the spinal cord (myelopathy).
Surgery to treat spinal stenosis usually involves removing a small amount of vertebral bone to relieve pressure on the affected nerves. The most common type of surgery to treat stenosis is called a laminectomy, though many options are available