Lumbar Spinal Canal Stenosis + Cauda Equina

The lumbar spinal canal is the space in the lower spine that carries nerves to your legs. It is very narrow. It gets even more narrow if the bone and tissue around it grow over the course of many years. This narrowing is called "stenosis." As the lumbar spinal canal narrows, the nerves that go through it are squeezed. This squeezing may cause back pain, and leg pain and weakness.

Arthritis, falls, accidents, and wear and tear on the spine's bones and joints can also cause narrowing of the spinal canal. These factors play a part in stenosis among many adults.

SYMPTOMS:

People with stenosis may have back or leg pain or numbness. Your legs might also feel cramped, tired or weak. These symptoms usually start when you are standing or walking. Often, the symptoms get better if you sit, crouch or lie in the fetal position (on your side with your knees tucked up to your chest). It's thought that these positions "open" the lumbar canal and take the pressure off the nerves that go to the legs.

In severe cases, stenosis can cause bowel or bladder problems.

DIAGNOSED:

Although your doctor can probably tell if you have stenosis by asking you about your symptoms, sometimes special tests and x-rays of the spine are needed to make the diagnosis.

Magnetic resonance imaging (MRI): A diagnostic test that produces three-dimensional images of body structures using magnetic fields and computer technology. MRI produces images of the spinal cord, nerve roots, and surrounding areas.

Myleogram: An x-ray of the spinal canal following injection of a contrast material into the surrounding cerebrospinal fluid spaces; can show displacement on the spinal cord or spinal nerves due to herniated discs, bone spurs, tumors, etc.

RELIEVE PAIN AND NUMBNESS:

Once you know you have lumbar spinal canal stenosis, you have several choices for treatment. Your treatment will depend on how bad your symptoms are. If your pain is mild and you haven't had it long, you can try an exercise program or a physical therapy program. This can strengthen your back muscles and improve your posture. Your doctor may also prescribe medicine to help reduce inflammation (soreness and swelling) in your spine.

If you have more severe symptoms, you may need to see a spine surgeon. The surgeon may recommend surgery to take the pressure off the nerves in your lower spine. This surgery works well for many people.

Sometimes, the term "cauda equina" is associated with this stenosis...

The cauda equina (CE) is formed by nerve roots caudal to the level of spinal cord termination. Cauda equina syndrome (CES) has been defined as low back pain, unilateral or usually bilateral sciatica, saddle sensory disturbances, bladder and bowel dysfunction, and variable lower extremity motor and sensory loss. CES may result from any lesion that compresses CE nerve roots. These nerve roots are particularly susceptible to injury, since they have a poorly developed epineurium. When well developed, as in peripheral nerves, they protect against compressive and tensile stresses. The microvascular systems of nerve roots have a region of relative hypovascularity in their proximal third. Increased vascular permeability and subsequent diffusion from the surrounding cerebral spinal fluid supplement the nutritional supply. This property of increased permeability may be related to the tendency toward edema formation of the nerve roots, which may result in edema compounding initial and sometimes seemingly slight injury.

Symptoms and Diagnosis

CES symptoms mimic those of other conditions. Its symptoms may vary in intensity and evolve slowly over time. CES is accompanied by a range of symptoms, the severity of which depend on the degree of compression and the precise nerve roots that are being compressed. Besides a herniated disc, other conditions with similar symptoms to CES include peripheral nerve disorder, conus medullaris syndrome, spinal cord compression, and irritation or compression of the nerves after they exit the spinal column and travel through the pelvis, a condition known as lumbosacral plexopathy.

Patients with back pain should be aware of the following "red flag" symptoms that may indicate CES:

• Severe low back pain
• Motor weakness, sensory loss, or pain in one, or more commonly both legs
• Saddle anesthesia (unable to feel anything in the body areas that sit on a saddle)
• Recent onset of bladder dysfunction (such as urinary retention or incontinence)
• Recent onset of bowel incontinence
• Sensory abnormalities in the bladder or rectum
• Recent onset of sexual dysfunction
• A loss of reflexes in the extremities

Medical history implications:

• Recent violent injury to the back
• Recent lumbar spine surgery
• A history of cancer
• Recent severe infection

Treatment

Once the diagnosis of CES is made, and the etiology established, urgent surgery is usually the treatment of choice. The goal is to reverse the symptoms of neural dysfunction. Left untreated, CES can result in permanent paralysis and incontinence.

Those experiencing any of the red flag symptoms should consult a neurosurgeon as soon as possible. Prompt surgery is the best treatment for patients with CES. Treating patients within 48 hours after the onset of the syndrome provides a significant advantage in improving sensory and motor deficits as well as urinary and rectal function. But even patients who undergo surgery after the 48-hour ideal timeframe may experience considerable improvement.

Although short-term recovery of bladder function may lag behind reversal of lower extremity motor deficits, the function may continue to improve years after surgery. Following surgery, drug therapy coupled with intermittent self-catheterization can help lead to slow, but steady recovery of bladder and bowel function.

Coping with CES

CES can affect people both physically and emotionally, in particular if it is chronic. People with CES may no longer be able to work, either because of severe pain, socially unacceptable incontinence problems, motor weakness and sensory loss, or a combination of these problems.

Loss of bladder and bowel control can be extremely distressing and have a highly negative impact on social life, work and relationships. Patients with CES may develop frequent urinary infections. Sexual dysfunction can be devastating to the patient and his/her partner and may lead to relationship difficulties and depression.

Severe nerve-type (neurogenic) pain may require prescription pain medication with side effects that may cause further problems. If the pain is chronic, it may become "centralized" and radiate to other areas of the body. Neurogenic pain tends to be worse at night and may interfere with sleep. This type of pain tends to produce a burning feeling that can become constant and unbearable. Sensory loss may range from pins and needles to complete numbness, and may affect the bladder, bowel and genital areas. Weakness is usually in the legs and may contribute to problems walking.

It is essential that people with CES receive emotional support from a network of friends and family members, if possible. It is important to work closely with your physician on medication and pain management. There are several medications prescribed to address pain, bladder and bowel problems. In addition, some patients find that physical therapy and psychological counseling help them cope with CES.