Spinal Stenosis

What is spinal stenosis?

Spinal stenosis is a condition in which one or more of the spaces within the spinal canal become narrowed. The spinal canal is a tube that runs through each vertebra in the spine and contains the spinal cord.

If there is less space within the spinal canal, the spinal cord and the nerves that branch from it can become compressed, pinched or irritated. This can cause back pain and nerve problems such as sciatica. For some, spinal stenosis can cause chronic back pain and other symptoms that have an impact daily life.

Spinal stenosis is a relatively common condition, usually affecting people over the age of 50.

Spinal stenosis usually affects two areas of the spine:

• Lower back: This is called lumbar spinal stenosis. The lumbar spine consists of five vertebrae, known as L1 to L5. They are the largest vertebrae in the spine.
• Neck: This is called cervical spinal stenosis. The cervical spine consists of seven vertebrae, known as C1 to C7.

Spinal stenosis in the middle back, known as the thoracic spine, is rare.

What are the symptoms of spinal stenosis?

Spinal stenosis symptoms will vary according to where the narrowing occurs and how severe it is. Symptoms usually develop over time, may come and go, and may affect people differently. The most common symptoms of spinal stenosis are pain, tingling, numbness and weakness felt in the back, neck, arms, hands, legs or feet.

What are the symptoms of lumbar spinal stenosis?

Lumbar spinal stenosis symptoms include:

• Lower back pain
• Pain that extends from the buttocks, down the legs
• Cramping in the legs
• Tingling or numbness in the buttock, legs or feet
• Pain that worsens when you walk or stand for a long time or when you walk downhill
• Pain that eases when you walk uphill or lean forward

What are the symptoms of cervical spinal stenosis?

Cervical spinal stenosis symptoms are felt below the point at which the nerves in your neck are compressed, and may include:

• Neck pain
• Balance problems
• Tingling or numbness in the arms, hands, legs or feet
• Weakness in the arms, hands, legs or feet
• Reduced function of the hands

What causes spinal stenosis?

There are a number of things that can cause spinal stenosis, which are split into two categories:

Acquired causes

Acquired spinal stenosis develops later in life and is the most common type. It usually develops because of wear and tear as you age, known as degenerative changes. It can also happen following an injury. Causes of acquired spinal stenosis include:

• Bone overgrowth: Osteoarthritis is a condition that causes cartilage in your joints, including those in your spine, to break down. Cartilage is the protective layer covering your joints and, as it wears away, your bones rub against each other. Your body grows new bone in response, known as bone spurs. If bone spurs form on your vertebrae and extend into the spinal canal, the space narrows and can pinch the nerves in your spine. Osteoarthritis is a degenerative condition caused by wear and tear.
• Bulging or herniated disks: There is a cushioning pad between each of your vertebrae, called a vertebral disk, which absorbs shock. When we age, these disks can flatten and dry out, causing cracks on the outer edge. This can lead to the disk’s gel-like center to break through and bulge or herniate, which then presses on nearby nerves.
• Thickened ligaments: Ligaments are bands of fibrous tissue that help hold the spine together. If you have arthritis, this can cause your ligaments to thicken and bulge into the spinal canal.
• Spinal fractures and injuries: Broken bones in your vertebrae, or inflammation from injuries, can cause the canal space to narrow.
• Spinal cysts or tumors: Growths on the spinal cord or near the vertebrae can narrow the spinal canal.

Congenital causes

Congenital spinal stenosis, which can affect babies and children, happens when the spine doesn’t develop properly or when an inherited condition affects bone growth. The causes of congenital spinal stenosis include:

• Achondroplasia: A genetic condition that affects bone growth and results in short stature.
• Spinal dysraphism: If the spine, spinal cord or nerve roots do not form properly it can lead to conditions such as spina bifida or other neural tube defects.
• Congenital kyphosis: This is when a child’s spine curves too far outward, due to a problem during fetal spine development.
• Congenital short pedicles: When the vertebral pedicles (the bony sides of the spinal canal) are too short at birth, they can decrease the size of the spinal canal.
• Osteopetrosis: A genetic condition that causes bones to become abnormally dense.
• Morquio syndrome: A genetic condition affecting the bones, spine and other body systems of children.
• Hereditary multiple exostoses: Also known as diaphyseal aclasis, this rare genetic condition causes small bone growths on a child’s vertebrae, which can affect the spinal canal.

How is spinal stenosis diagnosed?

Your doctor will discuss your medical history and symptoms if they suspect spinal stenosis and then perform a physical exam. They may also perform imaging tests to determine the location and extent of the stenosis. Imaging tests may include:

• Spinal X-ray
• Magnetic resonance imaging (MRI)
• CT scan
• CT myelogram (using contrast dye to view the spinal cord and nerves clearly).

How is spinal stenosis treated?

Treatment for spinal stenosis will depend on the cause, location, and severity of your symptoms.

If the symptoms of spinal stenosis are mild, your doctor may recommend at-home care such as applying a hot or cold compress or exercising to strengthen muscles to support the spine.

If at-home care does not help to alleviate symptoms, nonsurgical treatment may be recommended to help manage the symptoms. Nonsurgical treatments for spinal stenosis include:

• Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce inflammation and relieve pain. Other pain relief medications may also be recommended.
• Physical therapy: A program that includes exercises to help you gain strength and improve spine stability, balance and flexibility can help strengthen your back and abdominal muscles. Physical therapists will also teach you about posture and positioning help relieve pressure on your nerves.
• Steroid injections: Corticosteroid injections are given in the space around pinched spinal nerves. This can reduce pain, inflammation and irritation.

If nonsurgical treatments do not help you to manage the symptoms of spinal stenosis, surgery may be considered. Types of surgery to treat spinal stenosis include:

• Laminectomy: Known as decompression surgery, this is one of the most common surgeries for spinal stenosis. The lamina (part of the vertebra) is removed and, in some cases, ligaments and bone spurs are also removed to make more room for the spinal cord and nerves.
• Laminotomy: A partial laminectomy, in which only a part of the lamina (the area causing the most nerve pressure) is removed.
• Laminoplasty: A surgery used to treat cervical spinal stenosis in which the lamina is reshaped or repositioned to create more space in the spinal canal. Metal plates and screws may be used to hold the bone in its new position.
• Foraminotomy: A surgery to remove bone or tissue in the foramen, the opening in the vertebrae where your nerve roots exit, to create more space.
• Interspinous process spacers: A minimally invasive procedure to treat lumbar spinal stenosis. Spacers are placed between the bones that extend off the vertebrae (called the spinous processes), keeping the vertebrae apart and creating more space for your nerves.
• Spinal fusion: Also known as lumbar arthrodesis, this is may be considered when spinal stenosis is associated with spinal instability or when other treatments have not provided adequate relief. The surgery involves permanently joining two or more vertebrae together. Advanced, minimally invasive options, such as the Minuteman® procedure, achieve lumbar arthrodesis for lumbar spinal stenosis on an outpatient basis, alleviating lower back pain and other symptoms in select patients. Avoiding extensive bone removal and muscle stripping, the procedure can often be performed using a local anesthetic and some patients can return to normal activities within 24 hours.

Most cases of spinal stenosis are caused by age-related wear and tear and cannot be prevented, but keeping your spine healthy may reduce the risk of developing spinal stenosis or slow its progression. Eating a healthy diet, maintaining a weight that is healthy for you, exercising regularly and practicing good posture may all be beneficial.