Foraminal narrowing, also known as foraminal stenosis, is a condition that affects the foramen (singular: foramina) or openings in the vertebra that allow nerves branching from the spinal column to access the legs, arms and other parts of the body. Due to a variety of conditions and natural aging these openings may become narrowed or clogged over time.
Causes and Risk Factors
There are several issues that can cause foraminal stenosis. Most issues with foraminal narrowing occur in conjunction with aging and degenerative issues as people get older and their bodies began to wear down after years of wear. Obesity, participation in high-impact sports, sedentary lifestyles or jobs that require constant standing, sitting, lifting, bending and twisting increase the risk of foraminal stenosis in the future.
Medical and spinal conditions that can cause foraminal narrowing include:
- Bulging disc – the condition created when a disc extends outside of the area it normally occupies.
- Herniated disc – the condition created when a crack is made in the outer layer of cartilage of the disc and the soft cartilage inside begins to extend outward through the crack. This is sometimes referred to as a ruptured or slipped disc.
- Bone Spurs – an outgrowth of bone that occurs along the edges of bones, especially in joints or where 2 or more bones come together.
- Spondylolisthesis – a spinal condition where a vertebra in the back slips forward and onto the bone below it.
- Spinal injuries
- Degenerative disc disease – Not actually a disease but the conditions in which pain originates from a damaged disc between the vertebra.
- Genetic conditions or family history
Types of Foraminal Narrowing
There are several varying types of foraminal stenosis. They are commonly classified according to their locations along the spinal column.
- Cervical – Cervical foraminal stenosis impacts the head, neck and shoulders and can extend into the arms and hands and upper back.
- Thoracic – This affects the middle back region where the ribs and spine attach to one another. The range may also reach into the upper back and neck and down towards the lower back, hips and legs.
- Lumbar spine – stenosis which affects the lower back, hips legs and feet.
- Neural foraminal narrowing – Stenosis which affects the nerves and nervous system.
- Degenerative Foraminal stenosis – Foraminal narrowing that gradually develops as one ages.
- Bilateral – Each vertebra has two foramina, one on each side, to allow nerves to reach both sides of the body. Bilateral foraminal narrowing affects both of these openings meaning both are becoming smaller
Symptoms of Foraminal Narrowing
The most common symptoms associated with foraminal narrowing are pain, tingling, numbness and weakness. Another sensation described is the feeling of “pins-and-needles.” Depending on the type of stenosis that is causing this pain these sensations may occur in different areas of the body.
- Cervical – Pain and numbness will be localized to the neck, shoulders and upper back. In severe cases it may radiate down the arms and into the hands.
- Thoracic – Since thoracic foraminal narrowing affects the middle back the pain from it can reach into the upper back and down into the lower back and legs as well. Symptoms will range from muscle spasms, pain around the rib cage or pain in one or more of the internal organs.
- Lumbar – Again, lumbar foraminal narrowing will cause pain that ranges from the lower back, buttocks, legs and feet. This usually only happens to one leg. Cramping, weakness, and tingling will also occur. In severe cases there may be loss of bowel or bladder control, which indicates a medical emergency.
- Neural – Symptoms of neural foraminal narrowing will not usually be present. However when the foramina is narrowed enough to put pressure on the nerves pain, tingling and numbness can occur.
- Bilateral – Many of the same above symptoms will be present, however instead of occurring only on one side of the body both sides will be affected.
Diagnosis of Foraminal Narrowing
When diagnosing foraminal narrowing a doctor will begin by taking a comprehensive medical history of the patient. There are certain characteristics presented by foraminal stenosis that they will keep a watch for including:
- Symptoms that are not continuous.
- Develops slowly and over many years.
- Symptoms that are related to activity or positions, or pain that gets better or worse with either.
- Family history or genetic conditions that can cause foraminal narrowing.
The physician will also check for any issues with range of motion and a patient’s ability to move to determine if a certain area is affected. Once this first stage of the diagnosis process is complete there are some imaging tests that can be done to determine the exact cause of the symptoms.
- X-Ray – An x-ray can rule out the possibility that symptoms are being caused by an injury, tumor or other abnormality.
- Magnetic resonance imaging (MRI) – This will detect damage or the presence of disease in soft tissues such as discs or ligaments. Dye may be injected prior to the MRI to help clearly see any abnormalities in difficult areas.
- CT scan – This will show the shape of the spinal column and detect any abnormalities. This will sometimes also be done in conjunction with injecting dye into the spinal column.
- Bone scan – This will rule out any fractures, tumors, infections or the possibility of arthritis.
There are some conventional treatments that are employed to help relieve foraminal stenosis. These include non-steroidal medications, such as ibuprofen, restricted activity or physical therapy, corticosteriod shots, or the use of back braces. Heat and cold therapy can be used to help with pain and reduce swelling. Stretching in areas affected by foraminal stenosis can also offer some relief as well.
When these conventional treatments do not work surgical procedures are usually the next step in treatment. An operation called a foraminotomy may be performed to help take pressure off the nerves affected by the narrowing foramina.
The best way to determine if back pain is being caused by foraminal narrowing or another condition is to consult with a physician. They can determine the cause of the symptoms and proscribe a correct treatment regimen.