What is Neural Foraminal Narrowing?
Neural foraminal narrowing (foraminal stenosis) is a medical condition which occurs as a result of compression of the spinal nerve roots.1 Foramina are the openings present at every level of the spinal column through which the nerve roots pass. When there is narrowing or stenosis of these foramina, it causes compression of the nerve roots resulting in pain, numbness, tingling and/or weakness in the areas which are supplied by those specific nerves. A single nerve root on one side of the body is commonly affected by foraminal narrowing; however, there are some patients who may have bilateral foraminal narrowing, also known as bilateral neural stenosis, which occurs due to nerve compression on both the sides of the spine. Neural foraminal narrowing can cause lot of pain, discomfort and frustration to the patient, especially when the patient is in certain positions or engages in certain activities.
Neural foraminal narrowing can occur in the lower-back (lumbar region) or in the cervical (neck region). The causes for neural foraminal narrowing can be slipped disc, degeneration, osteophyte and failure of the disc space. Not all patients will exhibit symptoms, as the foramina will be often broad enough to allow the nerves to pass freely through the openings. Thus there are many individuals who suffer from neural foraminal stenosis and do not have symptoms and may not be aware of their condition. The symptoms, when they appear, will often affect only one side of the body; however, in bi-lateral foraminal stenosis, patient has symptoms on both sides of the body. The symptoms depend on the nerve involved.
Conservative treatment options for foraminal narrowing comprises of pain medications, which provide temporary relief. Activity modification and spinal surgery are other methods for alleviating pressure from the nerve root.
Causes of Neural Foraminal Narrowing
Neural foraminal narrowing or foraminal stenosis commonly occurs as a result of aging process. Other conditions which can cause neural foraminal narrowing include1:
- Disc degeneration due to aging process where the foramina may decrease in size due to loss of disc height.
- Rheumatoid arthritis.
- Spinal disc herniation where a part of the intervertebral disc protrudes into the foramen and compresses the nerve roots.
- Osteophyte (bone spur) can grow in the foramina making the space smaller thus pinching the nerve roots.
- Bulging disc where a part of the disc protrudes and compresses the nerve roots.
- Spondylolisthesis is a condition where there is forward slipping of the vertebra over another, which causes substantial decrease in the size of the foramina.
Signs & Symptoms of Neural Foraminal Narrowing
In most of the patients, neural foraminal narrowing affects the lumbar region where symptoms are produced in the lower extremities. Common symptoms which are present in neural foraminal narrowing are:
- If the sciatic nerve is affected, then symptoms of sciatica are produced, such as the patient has pain and finds it difficult to walk.
- Neurogenic claudication is a condition where the patient experiences leg weakness, numbness, and soreness upon walking. There is relief from the symptoms when the patient sits down and rests for some time.
- The symptoms of neural foraminal stenosis continue to worsen gradually over many years.
- The pain of neural foraminal stenosis develops gradually over a period of some years, is not continuous and is related to a certain position or an activity.
- Symptoms, such as leg discomfort and low back pain are experienced and they worsen after the patient stands or walks for some time.
- Sitting and forward flexion brings relief of the symptoms.
Investigations to Diagnose Neural Foraminal Narrowing
- Medical history and physical exam.
- CT scan.1
- MRI scan.1
What is the Treatment for Neural Foraminal Narrowing?
Treatment depends on the severity of the symptoms and the physical discomfort and disability which the patient is experiencing. Initial treatment comprises of exercises, physical therapy, task modifications, anti-inflammatories, pain killers and epidural injections.
- Rest alleviates the symptoms, so patient should take a break from his/her activities and rest awhile for relief of symptoms.
- Patients should avoid postures/positions and situations which worsen their pain and discomfort.
- Anti-inflammatory medications, such as ibuprofen and naproxen, help in relieving the pain.
- Epidural injections also can provide relief from the pain of the neural foraminal narrowing. These injections can be repeated every few months.
- Physical therapy can be started after consulting an experienced physical therapist
- If conservative methods, such as the above, do not provide relief; and the pain and discomfort persist then, surgery is recommended to relieve the pressure occurring from foraminal narrowing.
Surgery for Neural Foraminal Narrowing
Surgery is done in severe cases where the patient is severely disabled and is not able to perform normal daily activities of living. During the surgery the affected region is opened up and the pressure is relieved from the nerve root compression. Surgical decompression is a surgical procedure which provides the patient with relief from the symptoms and better performance of their daily activities. Spinal fusion can be done along with spinal decompression to achieve better stability of the spinal column, especially in cases where there is, along with the removal of a bone spur, removal of an aspect of the joint. In such cases, a spinal fusion helps in achieving equilibrium.