Spinal stenosis is a narrowing of the spinal canal, the space in the back that surrounds and protects the spinal cord.
Spinal stenosis may cause:
- Balance problems
- Weakness or numbness in the extremities -This is because of pressure on the spinal cord and nerves.
Spinal stenosis is most common in the lower back (lumbar spinal stenosis). It can cause leg and back symptoms — especially when standing upright. You may be able to relieve this by leaning forward. Neck (cervical) disease may cause upper and lower extremity problems.
The narrowing may have been there since birth. Or, it may have developed over time due to arthritis, calcium deposits in spinal ligaments, disk disease, injury or a combination of these. The onset of symptoms tends to be quite gradual with these causes of spinal stenosis.
More serious causes of spinal stenosis, including infection, tumor and bleeding, are rare and usually develop more rapidly.
When suspected, spinal stenosis and its cause can be confirmed by MRI or CT scan.
Initial treatment options for the most common types of spinal stenosis include:
- Pain medicine, such as acetaminophen
- Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or aspirin
- Muscle relaxants, since muscle spasm may accompany nerve irritation
- Physical therapy for stretching, strengthening and postural training
If there is no improvement, your doctor may recommend corticosteroids, which are powerful anti-inflammatory agents. Sometimes, doctors prescribe a short course of an oral corticosteroid, such as prednisone. Or, he or she may refer you for a limited number of corticosteroid injections during which the medication is injected into the space just outside the spinal cord (the epidural space). This reduces swelling and inflammation in or near the compressed nerves.
These injections are performed by a person experienced in the procedure. This often happens in a specialized pain unit or other setting where X-ray guidance is available. That way, the site of the injection is precise.
It’s hard to know how successful these injections are: the overall success rate varies widely in the published literature, often in the range of 40-80%. The success rate may vary depending on the experience of doctor, the severity and location of the narrowed area and whether there are other causes of symptoms.
Some studies (and doctors) are more selective than others in choosing the best candidates for these injections. Also, the specific cause (such as arthritis, disk, or ligament calcification) may play a role in the success rate. Finally, improvement in symptoms may be more dramatic soon after the injection and wane with time. Most doctors who give these injections believe that some (or most) people will respond well to these injections, allowing many to avoid surgery.
As with any treatment, there are risks to consider when receiving corticosteroid injections for spinal stenosis. These include:
- Discomfort or numbness during the injection
- Bleeding along the path of the needle
- Nerve damage
Fortunately, serious complications are quite rare.
Surgery is usually the last resort but it can ease or even eliminate symptoms. It’s a major operation. The surgeon removes pieces of bone, calcified ligaments and/or disks. The goal is to relieve pressure on the spinal cord and nerves.