Spinal stenosis is a narrowing of the spinal canal, which places pressure on the spinal cord. If the stenosis is located on the lower part of the spinal cord it is called lumbar spinal stenosis. Stenosis in the upper part of the spinal cord is called cervical spinal stenosis. While spinal stenosis can be found in any part of the spine, the lumbar and cervical areas are the most commonly affected.

What Causes Spinal Stenosis?
Some patients are born with this narrowing, but most often spinal stenosis is seen in patients over the age of 50. In these patients, stenosis is the gradual result of aging and "wear and tear" on the spine during everyday activities. There most likely is a genetic predisposition to this since only a minority of individuals develops advanced symptomatic changes. As people age, the ligaments of the spine can thicken and harden (called calcification). Bones and joints may also enlarge, and bone spurs (called osteophytes) may form. Bulging or herniated discs are also common. Spondylolisthesis (the slipping of one vertebra onto another) also occurs and leads to compression. When these conditions occur in the spinal area, they can cause the spinal canal to narrow, creating pressure on the spinal nerve.

Symptoms of Stenosis
The narrowing of the spinal canal itself does not usually cause any symptoms. It is when inflammation of the nerves occurs at the level of increased pressure that patients begin to experience problems. Patients with lumbar spinal stenosis may feel pain, weakness, or numbness in the legs, calves or buttocks. In the lumbar spine, symptoms often increase when walking short distances and decrease when the patient sits, bends forward or lies down. Cervical spinal stenosis may cause similar symptoms in the shoulders, arms, and legs; hand clumsiness and gait and balance disturbances can also occur. In some patients the pain starts in the legs and moves upward to the buttocks; in other patients the pain begins higher in the body and moves downward. This is referred to as a "sensory march". The pain may radiate like sciatica or may be a cramping pain. In severe cases, the pain can be constant. Severe cases of stenosis can also cause bladder and bowel problems, but this rarely occurs. Also paraplegia or significant loss of function also rarely, if ever, occurs.

How Stenosis is Diagnosed
Before making a diagnosis of stenosis, it is important for the doctor to rule out other conditions that may have similar symptoms. In order to do this, most doctors use a combination of tools, including :

• History
  The doctor will begin by asking the patient to describe any symptoms he or she is having and how the symptoms have changed over time. The doctor will also need to know how the patient has been treating these symptoms including what medications the patient has tried.
  
  
• Physical Examination
  The doctor will then examine the patient by checking for any limitations of movement in the spine, problems with balance and signs of pain. The doctor will also look for any loss of extremity reflexes, muscle weakness, sensory loss, or abnormal reflexes which may suggest spinal cord involvement.
  
  
• Tests
  After examining the patient, the doctor can use a variety of tests to look at the inside of the body. Examples of these tests include :
  • X-rays - these tests can show the structure of the vertebrae and the outlines of joints and can detect calcification.
  • MRI (magnetic resonance imaging) - this test gives a three-dimensional view of parts of the back and can show the spinal cord, nerve roots, and surrounding spaces, as well as enlargement, degeneration, tumors or infection.
  • Computerized axial tomography (CAT scan) - this test shows the shape and size of the spinal canal, its contents and structures surrounding it. It shows bone better than nerve tissue.
  • Myelogram - a liquid dye is injected into the spinal column and appears white against bone on an x-ray film. A myelogram can show pressure on the spinal cord or nerves from herniated discs, bone spurs or tumors.
  • Bone Scan - This test uses injected radioactive material that attaches itself to bone. A bone scan 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.

Non-surgical Treatment of Spinal Stenosis
There are a number of ways a doctor can treat stenosis without surgery. These include :

• Medications, including non-steroidal anti-inflammatory drugs (NSAIDs) to reduce swelling and pain, and analgesics to relieve pain.
• Corticosteroid injections (epidural steroids) can help reduce swelling and treat acute pain that radiates to the hips or down the leg. This pain relief may only be temporary and patients are usually not advised to get more than 3 injections per 6-month period.
• Rest or restricted activity (this may vary depending on extent of nerve involvement).
• Physical therapy and/or prescribed exercises to help stabilize the spine, build endurance and increase flexibility.

Surgical Treatment of Spinal Stenosis
In many cases, non-surgical treatments do not treat the conditions that cause spinal stenosis, however they might temporarily relieve pain. Severe cases of stenosis often require surgery. The goal of the surgery is to relieve pressure on the spinal cord or spinal nerve by widening the spinal canal. This is done by removing, trimming, or realigning involved parts that are contributing to the pressure.

The most common surgery in the lumbar spine is called decompressive laminectomy in which the laminae (roof) of the vertebrae are removed to create more space for the nerves. A surgeon may perform a laminectomy with or without fusing vertebrae or removing part of a disc. Various devices (like screws or rods) may be used to enhance fusion and support unstable areas of the spine.

Other types of surgery to treat stenosis include the following :

• Laminotomy - when only a small portion of the lamina is removed to relieve pressure on the nerve roots;
• Foraminotomy - when the foramin (the area where the nerve roots exit the spinal canal) is removed to increase space over a nerve canal. This surgery can be done alone or along with a laminotomy;
• Medial Facetectomy - when part of the facet (a bony structure in the spinal canal) is removed to increase the space;
• Anterior Cervical Discectomy and Fusion - the cervical spine is reached through a small incision in the front of the neck. The intervertebral disc is removed and replaced with a small plug of bone, which in time will fuse the vertebrae.
• Cervical Corpectomy - when a portion of the vertebra and adjacent intervertebral discs are removed for decompression of the cervical spinal cord and spinal nerves. A bone graft, and in some cases a metal plate and screws, is used to stabilize the spine.
• Laminoplasty - a posterior approach in which the cervical spine is reached from the back of the neck and involves the surgical reconstruction of the posterior elements of the cervical spine to make more room for the spinal canal.

Overhead View of a Cervical Vertebra

1. Spinous Process
2. Lamina
3. Zygapophysial Joint (Facet)
4. Posterior Tubercle
5. Foramin
6. Pedicle
7. Body

If nerves were badly damaged before the surgery, the patient may still have some pain or numbness after the surgery. Or there may be no improvement at all. Also, the degenerative process will likely continue, and pain or limitation of activity may reappear 5 or more years after surgery.

Most doctors will not consider surgical treatment of spinal stenosis unless several months of non-surgical treatment methods have been tried. Since all surgical procedures carry a certain amount of risk, patients are advised to discuss all treatment options with their doctor before deciding which procedure is best.

What Is Spondylolisthesis
Spondylolisthesis occurs when one vertebra slips forward in relation to an adjacent vertebra, usually in the lumbar spine. The symptoms that accompany a spondylolisthesis include pain in the low back, thighs, and/or legs, muscle spasms, weakness, and/or tight hamstring muscles. Some people are symptom free and find the disorder exists when revealed on an x-ray. In advanced cases, the patient may appear swayback with a protruding abdomen, exhibit a shortened torso, and present with a waddling gait.

Spondylolisthesis can be congenital (present at birth) or develop during childhood or later in life. The disorder may result from the physical stresses to the spine from carrying heavy things, weightlifting, football, gymnastics, trauma, and general wear and tear. As the vertebral components degenerate the spine's integrity is compromised.

Another type of spondylolisthesis is degenerative spondylolisthesis, occurring usually after age 50. This may create a narrowing of the spinal canal (spinal stenosis). This condition is frequently treated by surgery.

Diagnosis of Spondylolisthesis
A routine lateral (side) radiograph taken while standing confirms a diagnosis of a spondylolisthesis. The x-ray will show the translation (slip) of one vertebra over the adjacent level, usually the one below.

Using the lateral (side) x-ray, the slip is graded according to its degree of severity. The Myerding grading system measures the percentage of vertebral slip forward over the body beneath. The grades are as follows :

• Grade 1: 25%
• Grade 2: 25% to 49%
• Grade 3: 50% to 74%
• Grade 4: 75% to 99%
• Grade 5: 100%*

*Complete vertebral slippage, known as spondyloptosis.

Non-Surgical Treatment
If the spondylolisthesis is non-progressive, no treatment except observation is required. Symptoms often abate once precipitating activities cease. Conservative treatment includes 2 or 3 days of bed rest, restriction of activities causing stress to the lumbar spine (e.g. heavy lifting, stooping), physical therapy, anti-inflammatory and pain reducing medications, and/or a corset or brace.

A physician may prescribe a custom-made corset or brace. These are made by an orthotist, a professional who takes the patient's precise body measurements, which may include making a cast from which the molded orthoses is made.

Spine Surgery
Surgical intervention is considered when neurologic involvement exists or conservative treatment has failed to provide relief from long-term back pain and other symptoms associated with spondylolisthesis.

A spine surgeon decides which surgical procedure and approach (anterior/posterior, front or back) is best for the patient. His decisions are based on the patient's medical history, symptoms, radiographic findings, as well as the grade and angle of the vertebral slip. A variety of surgical treatment options are utilized. You should discuss what is best for your condition with your spine surgeon.

Recovery
Whether the treatment course is conservative or surgical, it is important to closely follow the instructions of your physician and/or physical therapist.

Avoid heavy lifting, stooping, or certain sports such as football or high impact exercise (i.e. running, aerobics). Any doubts concerning vocational and recreational restrictions should be discussed with your physician and/or physical therapist. They will be able to suggest safe alternatives to help reduce the risk of further back problems.

Keep your weight close to ideal, continue to follow the exercise program designed by your physical therapist at home, learn how to pick up things off the floor correctly, as well as other 'safe' movements.

Lumbar laminectomy is a surgical procedure most often performed to treat leg pain related to herniated discs, spinal stenosis, and other related conditions. Stenosis occurs as people age and the ligaments of the spine thicken and harden, discs bulge, bones and joints enlarge, and bone spurs (called osteophytes) form. Spondylolisthesis (the slipping of one vertebra onto another) can also lead to compression.

The goal of a laminectomy is to relieve pressure on the spinal cord or spinal nerve by widening the spinal canal. This is done by removing or trimming the lamina (roof) of the vertebrae to create more space for the nerves. A surgeon may perform a laminectomy with or without fusing vertebrae or removing part of a disc. Various devices (like screws or rods) may be used to enhance the ability to obtain a solid fusion and support unstable areas of the spine.

Quick Anatomy Lesson
The human spine extends from the skull to the pelvis. It is made up of individual bones called vertebrae. The vertebrae, which are stacked on top of each other, are grouped into four regions :

1. The cervical spine or neck (which is made up of 7 vertebrae C1 - C7) which effect neck, arms, hands
2. The thoracic spine or chest area (which is made up of 12 vertebrae T1 - T12) which effect torso, parts of the arms
3. The lumbar spine or low back (which is made up of 5 vertebrae T12 - L5) which effect hips, legs
4. The sacrum or pelvis area (which has 5 fused, non-separated vertebrae S1 - S5) which effect groin, toes, parts of the leg

The base of the spine, the coccyx (or tail bone), includes partially fused vertebrae and is mobile.

The vertebrae are separated from one another by soft pads, called intervertebral discs, which allow the spine to bend and flex and act as shock absorbers during regular activity. These discs also prevent the vertebrae from rubbing against each other. Each disc is made up of two parts, a soft center called the nucleus and a tough outer band called the annulus.

Throughout the length of the spine is a central tube, surrounded by bone and discs, called the spinal canal. Inside the spinal canal are the spinal cord, the cauda equina, and spinal nerves. The spinal cord begins at the base of the brain and ends in the lumbar spine area in a bundle of nerves known as the cauda equina. A pair of spinal nerves branch out (one to the left and one to the right) at each vertebral level. These provide sensation and movement to all parts of the body.

A lumbar laminectomy may be necessary to relieve pressure on the spinal canal.

How the Procedure is Done
The patient is usually positioned face down on an operating frame. A small incision (usually about 3-4 inches, though it may be longer depending on how many levels of the spine are affected) is made in the lower back.

The surgeon uses a retractor to spread apart the muscles and fatty tissue of the spine and exposes the lamina. A portion of the lamina is removed to uncover the ligamentum flavum - an elastic ligament that helps connect two vertebrae.

Next an opening is cut in the ligamentum flavum in order to reach the spinal canal. Once the compressed nerve can be seen, the cause of compression can be identified. Most cases of spinal compression are caused by a herniated disc. However, other sources of pressure that can cause compression may include :

1. A disc fragment (this will often cause more severe symptoms)
2. An osteophyte or bone spur (a rough protrusion of bone)
3. Protruding/degenerating discs
4. Facet arthritis and/or cysts
5. Tumors

The surgeon retracts the compressed nerve and the source of the compression is removed and pressure on the spinal nerve or nerve components is relieved.

If necessary, the surgeon will perform a spinal fusion with instrumentation to help stabilize the spine. This occurs when a lot of bone needs to be removed and/or when multiple levels are operated on. A spinal fusion involves grafting a small piece of bone (usually taken from the patient's own pelvis) onto the spine and using spinal hardware, such as screws and rods, to support the spine and provide stability.

Then the procedure is finished! The surgeon will close the incision either using absorbable sutures (stitches), which absorb on their own and do not need to be removed, or skin sutures, which will have to be removed by the surgeon after the incision has healed.