What is Foraminal Stenosis?

Foraminal stenosis is a narrowing of the spinal foramen, the hole through which passes a spinal nerve as it exits the spine (foramen basically just means "hole"). It is usually a form of degenerative spine disease which occurs slowly over time with wear and tear of the spinal column. Arthritic changes of the spine, including herniated discs and bulging discs, soft tissue swelling and bony growth can all impinge on the formal foramen and compress the nerve within.

A foramen exists at each level of the spine with one on each side. At each level, a spinal nerve, a nerve coming to or from the spinal cord, passes through the foramen. Because the foramen is a relatively small area, anything impinging on that area can cause foraminal stenosis is pinch the nerves inside the foramen.

While foraminal stenosis generally occurs in the setting of other degenerative disease of the spine, it can present as the primary problem in some patients. It can cause symptoms as only one level or at many at the same time if many foramina (the plural of foramen) are involved.

Symptoms of Foraminal Stenosis

Because the narrowing (stenosis) of the foramen pinches a nerve, the primary symptoms related to this disorder is directly related to that nerve which is affected. This obviously varies depending on which foramina are involved.

Any one foramina contains one nerve which goes to specific parts of the body. A left-sided foramen contains a nerve which only goes to the left side of the body. Therefore, the symptoms associated with foraminal stenosis will always be on the side of the stenosis. It can affect both sensory and motor function in the area that the nerve normally goes to (see below).

Generally, foramen disease in the lower part of the spine, called the lumbar region, will lead to symptoms in the leg. Likewise, disease in the neck, called the cervical region, will lead to symptoms in the arm.

The pinched nerve can lead to basically two classes of symptoms. First of all, sensory symptoms can occur, including pain in the distribution of that nerve as well as numbness, tingling and other sensory abnormalities.

Also, motor symptoms can occur, including weakness, abnormal reflexes and even paralysis in severe cases. However, unlike paralysis that occurs from damage to the spinal cord itself, this weakness or paralysis is one sided (unless the foramina of both sides are affected greatly) and limited to the muscles that are normally controlled by that specific nerve.

Treatment of Foraminal Stenosis

Treatment for degenerative spine disease varies considerably from patient to patient. In the case of foraminal stenosis, the treatment varies as well. Most patients will be recommended to first undergo a period of conservative therapy with rest, physical therapy and/or anti-inflammatory medications. In some cases this is enough for the pressure on the nerve to abate and for the symptoms to improve.

Other options are spinal injections which help to decrease the inflammation in the area. Finally, if all else fails or if the stenosis and symptoms are severe enough, some patients will be offered surgical treatment. Surgery often involves other procedures to address other degenerative disease of the spine that may be occurring at the same time. However, the procedure generally used to specifically address foraminal stenosis is called a Foramenotomy.