Spine Pain Management

Your spine, or backbone, protects your spinal cord and allows you to stand and bend. Spinal stenosis causes narrowing in your spine. The narrowing can occur at the center of your spine, in the canals branching off your spine and/or between the vertebrae, the bones of the spine. The narrowing puts pressure on your nerves and spinal cord and can cause pain.

Spinal stenosis occurs mostly in people older than 50. Younger people with a spine injury or a narrow spinal canal are also at risk. Diseases such as arthritis and scoliosis can cause spinal stenosis, too. Symptoms might appear gradually or not at all. They include pain in your neck or back, numbness, weakness or pain in your arms or legs, and foot problems. Treatments include medications, physical therapy, braces and surgery.

Who Gets Spinal Stenosis?

This disorder is most common in men and women over 50 years of age. However, it may occur in younger people who are born with a narrowing of the spinal canal or who suffer an injury to the spine.

What Structures of the Spine Are Involved?

The spine is a column of 26 bones that extend in a line from the base of the skull to the pelvis. Twenty-four of the bones are called vertebrae. The bones of the spine include 7 cervical vertebrae in the neck; 12 thoracic vertebrae at the back wall of the chest; 5 lumbar vertebrae at the inward curve (small) of the lower back; the sacrum, composed of 5 fused vertebrae between the hip bones; and the coccyx, composed of 3 to 5 fused bones at the lower tip of the vertebral column. The vertebrae link to each other and are cushioned by shock-absorbing disks that lie between them.

The vertebral column provides the main support for the upper body, allowing humans to stand upright or bend and twist, and it protects the spinal cord from injury. Following are structures of the spine most involved in spinal stenosis.

• Intervertebral disks - pads of cartilage filled with a gel-like substance which lie between vertebrae and act as shock absorbers.
• Facet joints - joints located on the back of the main part of the vertebra. They are formed by a portion of one vertebra and the vertebra above it. They connect the vertebrae to each other and permit backward motion.
• Intervertebral foramen (also called neural foramen) - an opening between vertebrae through which nerves leave the spine and extend to other parts of the body.
• Lamina - part of the vertebra at the back portion of the vertebral arch that forms the roof of the canal through which the spinal cord and nerve roots pass.
• Ligaments - elastic bands of tissue that support the spine by preventing the vertebrae from slipping out of line as the spine moves. A large ligament often involved in spinal stenosis is the ligamentum flavum, which runs as a continuous band from lamina to lamina in the spine.
• Pedicles - narrow stem-like structures on the vertebrae that form the walls of the front part of the vertebral arch.
• Spinal cord/nerve roots - a major part of the central nervous system that extends from the base of the brain down to the lower back and that is encased by the vertebral column. It consists of nerve cells and bundles of nerves. The cord connects the brain to all parts of the body via 31 pairs of nerves that branch out from the cord and leave the spine between vertebrae.
• Synovium - a thin membrane that produces fluid to lubricate the facet joints, allowing them to move easily.
• Vertebral arch - a circle of bone around the canal through which the spinal cord passes. It is composed of a floor at the back of the vertebra, walls (the pedicles), and a ceiling where two laminae join.
• Cauda equina - a sack of nerve roots that continues from the lumbar region, where the spinal cord ends, and continues down to provide neurologic function to the lower part of the body. It resembles a "horse's tail" (cauda equina in Latin).

What Causes Spinal Stenosis?

The normal vertebral canal (see fig. 4) provides adequate room for the spinal cord and cauda equina. Narrowing of the canal, which occurs in spinal stenosis, may be inherited or acquired. Some people inherit a small spinal canal (see fig. 5) or have a curvature of the spine (scoliosis) that produces pressure on nerves and soft tissue and compresses or stretches ligaments. In an inherited condition called achondroplasia, defective bone formation results in abnormally short and thickened pedicles that reduce the diameter (distance across) of the spinal canal.

What Are the Symptoms of Spinal Stenosis?

The space within the spinal canal may narrow without producing any symptoms. However, if narrowing places pressure on the spinal cord, cauda equina, or nerve roots, there may be a slow onset and progression of symptoms. The neck or back may or may not hurt. More often, people experience numbness, weakness, cramping, or general pain in the arms or legs. If the narrowed space within the spine is pushing on a nerve root, people may feel pain radiating down the leg (sciatica). Sitting or flexing the lower back should relieve symptoms. (The flexed position "opens up" the spinal column, enlarging the spaces between vertebrae at the back of the spine.) Flexing exercises are often advised, along with stretching and strengthening exercises.

People with more severe stenosis may have problems with bowel and bladder function and foot disorders. For example, cauda equina syndrome is a severe, and very rare, form of spinal stenosis. It occurs because of compression of the cauda equina, and symptoms may include loss of control of the bowel, bladder, or sexual function and/or pain, weakness, or loss of feeling in one or both legs. Cauda equina syndrome is a serious condition requiring urgent medical attention.

How Is Spinal Stenosis Diagnosed?

The doctor may use a variety of approaches to diagnose spinal stenosis and rule out other conditions.

• Medical history - the patient tells the doctor details about symptoms and about any injury, condition, or general health problem that might be causing the symptoms.
• Physical examination - the doctor (1) examines the patient to determine the extent of limitation of movement, (2) checks for pain or symptoms when the patient hyperextends the spine (bends backwards), and (3) checks for normal neurologic function (for instance, sensation, muscle strength, and reflexes) in the arms and legs.
• X ray - an x-ray beam is passed through the back to produce a two-dimensional picture. An x ray may be done before other tests to look for signs of an injury, tumor, or inherited problem. This test can show the structure of the vertebrae and the outlines of joints, and can detect calcification.
• MRI (magnetic resonance imaging) - energy from a powerful magnet (rather than x rays) produces signals that are detected by a scanner and analyzed by computer. This produces a series of cross-sectional images ("slices") and/or a three-dimensional view of parts of the back. An MRI is particularly sensitive for detecting damage or disease of soft tissues, such as the disks between vertebrae or ligaments. It shows the spinal cord, nerve roots, and surrounding spaces, as well as enlargement, degeneration, or tumors.
• Computerized axial tomography (CAT) - x rays are passed through the back at different angles, detected by a scanner, and analyzed by a computer. This produces a series of cross-sectional images and/or three-dimensional views of the parts of the back. The scan shows the shape and size of the spinal canal, its contents, and structures surrounding it.
• Myelogram - a liquid dye that x rays cannot penetrate is injected into the spinal column. The dye circulates around the spinal cord and spinal nerves, which appear as white objects against bone on an x-ray film. A myelogram can show pressure on the spinal cord or nerves from herniated disks, bone spurs, or tumors.
• Bone scan - an injected radioactive material attaches itself to bone, especially in areas where bone is actively breaking down or being formed. The test can detect fractures, tumors, infections, and arthritis, but may not tell one disorder from another. Therefore, a bone scan is usually performed along with other tests.

Who Treats Spinal Stenosis?

Nonsurgical treatment of spinal stenosis may be provided by internists or general practitioners. The disorder is also treated by specialists such as rheumatologists, who treat arthritis and related disorders; and neurologists, who treat nerve diseases. Orthopaedic surgeons and neurosurgeons also provide nonsurgical treatment and perform spinal surgery if it is required. Allied health professionals such as physical therapists may also help treat patients.

What Are Some Nonsurgical Treatments for Spinal Stenosis?

In the absence of severe or progressive nerve involvement, a doctor may prescribe one or more of the following conservative treatments:

• Nonsteroidal anti-inflammatory drugs, such as aspirin, naproxen (Naprosyn)², ibuprofen (Motrin, Nuprin, Advil), or indomethacin (Indocin), to reduce inflammation and relieve pain.
• Analgesics, such as acetaminophen (Tylenol), to relieve pain.
• Corticosteroid injections into the outermost of the membranes covering the spinal cord and nerve roots to reduce inflammation and treat acute pain that radiates to the hips or down a leg.
• Anesthetic injections, known as nerve blocks, near the affected nerve to temporarily relieve pain.
• Restricted activity (varies depending on extent of nerve involvement).
• Prescribed exercises and/or physical therapy to maintain motion of the spine, strengthen abdominal and back muscles, and build endurance, all of which help stabilize the spine. Some patients may be encouraged to try slowly progressive aerobic activity such as swimming or using exercise bicycles.
• A lumbar brace or corset to provide some support and help the patient regain mobility. This approach is sometimes used for patients with weak abdominal muscles or older patients with degeneration at several levels of the spine.
  

What Are Some Alternative Therapies for Spinal Stenosis?

Alternative (or complementary) therapies are diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine. Some examples of these therapies used to treat spinal stenosis follow:

• Chiropractic treatment - This treatment is based on the philosophy that restricted movement in the spine reduces proper function and may cause pain. Chiropractors may manipulate (adjust) the spine to restore normal spinal movement. They may also employ traction, a pulling force, to help increase space between the vertebrae and reduce pressure on affected nerves. Some people report that they benefit from chiropractic care. Research thus far has shown that chiropractic treatment is about as effective as conventional, nonoperative treatments for acute back pain.
• Acupuncture - This treatment involves stimulating certain places on the skin by a variety of techniques, in most cases by manipulating thin, solid, metallic needles that penetrate the skin. Research has shown that low back pain is one area in which acupuncture has benefited some people. Dr. Shinaman is trained in acupuncture and can help treat you.

More research is needed before the effectiveness of these or other possible alternative therapies can be definitively stated. Health care providers may suggest these therapies in addition to more conventional treatments.

When Should Surgery Be Considered and What Is Involved?

In many cases, the conditions causing spinal stenosis cannot be permanently altered by nonsurgical treatment, even though these measures may relieve pain for a period of time. To determine how much nonsurgical treatment will help, a doctor may recommend such treatment first. However, surgery might be considered immediately if a patient has numbness or weakness that interferes with walking, impaired bowel or bladder function, or other neurological involvement. The effectiveness of nonsurgical treatments, the extent of the patient's pain, and the patient's preferences may all factor into whether or not to have surgery.

The purpose of surgery is to relieve pressure on the spinal cord or nerves and restore and maintain alignment and strength of the spine. This can be done by removing, trimming, or adjusting diseased parts that are causing the pressure or loss of alignment. The most common surgery is called decompressive laminectomy: removal of the lamina (roof) of one or more vertebrae to create more space for the nerves. A surgeon may perform a laminectomy with or without fusing vertebrae or removing part of a disk. Various devices may be used to enhance fusion and strengthen unstable segments of the spine following decompression surgery.

Patients with spinal stenosis caused by spinal trauma or achondroplasia may need surgery at a young age. When surgery is required in patients with achondroplasia, laminectomy (removal of the roof) without fusion is usually sufficient.