Lumbar Disc Disease

The pain may radiate down the front, side, or back of your leg, or it may be confined to the low back.

Low back pain is a very common complaint in the aging population. Fortunately, most episodes of low back pain are self-limiting and resolve within approximately six weeks, regardless of treatment.

In most cases of lower back pain, no specific imaging studies or treatment is needed. It is important to first rule out any serious causes of low back pain that need further evaluation by a doctor. "Red flags" (or clues that something more serious could be causing the low back pain) include the following warning signs:

• Age younger than 20 years or older than 50 years
• Major trauma
• History of cancer or recent infection
• Pain worse at night
• Change in bowel or bladder control
• Use of intravenous drugs
• Progressive neurologic deficit or weakness

Along with serious conditions suggested by the above warning signs, there are many other causes of low back pain. In fact, many patients with low back pain are never formally diagnosed with a specific cause.

Lumbar disc disease refers to a collection of degenerative disorders that can lead to low back pain as people age. It is also known as lumbar spondylosis. There are three main processes that make up lumbar disc disease:

• Internal disc disruption
• Degenerative disc disease
• Segmental instability

This article discusses lumbar disc disease, along with its clinical features, typical diagnostic steps, and treatment options.

People with lumbar disc disease typically develop complaints of chronic low back pain between the ages of 20 and 50 years. Often there is no history of a traumatic event preceding the onset of pain.

• Pain is often made worse with sitting or bending forward. There is localized tenderness in the lower back. Pain is persistent and lasts longer than six weeks.
• Men and women are equally affected.
• The symptoms of lumbar disc disease worsen as the degenerative changes in the spine progress from internal disc disruption to degenerative disc disease to segmental instability.
• With internal disc disruption, people have a deep ache in the low back that increases over several months. Pain is worse with motion.
• When this condition progresses, degenerative disc disease pain is present in the low back as well as the back of the buttocks and thighs.
• People with segmental instability have increasing pain radiating down the lower extremities. This pain is increased with movement and walking.

Lumbar disc disease is caused by normal degenerative changes that occur as a person ages. The lumbar spine is composed of motion segments. Each motion segment consists of two vertebral bodies, the intervertebral disc, and two facet joints. The intervertebral disc acts as the cushion, or "shock absorber," of the spine.

The intervertebral disc is made up mostly of water. This allows it to maintain its cushion-like properties. As people age, the intervertebral disc loses some of its water content. As this happens, the outer layers of the disc are more likely to develop cracks or tears. These can be a significant source of low back pain. This is the beginning of internal disc disruption.

When the outer layer of the disc cracks, the disc loses its normal water content. This reduces its ability to act as a cushion for the loads applied to the spine. Eventually, it leads to a collapse of the disc and degenerative changes in both the vertebral bodies and the facet joints of the spine. When this occurs, the condition is known as degenerative disc disease.

The final process in lumbar disc disease occurs when the degenerative changes lead to the destruction of the ligamentous and other soft tissue restraints of the spine. This is known as segmental instability, which occurs when a loss of the normal structural stability of the spinal segment occurs.

Most adults will have an episode or multiple episodes of low back pain during their lives. Most of these episodes do not require a visit to the doctor. The majority of low back pain resolves without any treatment or with over-the-counter medications and a short period of rest.

However, any person with the "red flag symptoms" (the warning signs listed above) should be evaluated by a doctor.

Questions to Ask the Doctor

• Are there any physical therapy programs or exercises that might help my symptoms?
• Would I benefit from surgery? This should only be a concern if the pain has not improved with conservative treatment. Surgical options to discuss with the doctor include lumbar decompression, lumbar fusion, and lumbar disc replacement. If considering surgery, discuss the risks and benefits of each of these surgical interventions with the surgeon.

A doctor first takes a complete medical history to determine what the symptoms are, when they began, what treatment has already been attempted, and what other medical conditions might be present.

Next, a complete physical exam with a focused exam of the lower back is performed. This includes evaluating the strength in the lower back and leg muscles as well as testing the reflexes and sensations in the legs.

Since most cases of low back pain resolve spontaneously without a specific diagnosis, the doctor may not initially order any other tests.

• Imaging studies may include plain X-rays films, CT scans, or MRI of the lumbar spine. These imaging studies need to be interpreted carefully since many people have normal changes seen in these studies as they age, without having physical symptoms. Any diagnosis should be based on specific findings from the history and physical exam that are supported by imaging studies.
• If a suspicion of infection, tumor, or inflammatory disorder arises, blood tests may be performed for further evaluation.
• A doctor may also order tests to determine if the nerves in the back are being compressed. These tests include EMGs (electromyogram, a test that records the activity of muscles) or nerve conduction studies.

Self-Care at Home

Most cases of low back pain can be effectively managed by the person at home. A short period of rest and over-the-counter medications can help with pain relief.

If symptoms do not resolve, the person should seek medical care for further evaluation.

Medical Treatment

Medical treatment for lumbar disc disease is typically limited to providing a structured program of physical therapy and medications as described in "Medications."

Again, other causes of low back pain need to be ruled out that would need more aggressive medical care.

Medications

Initial treatment of lumbar disc disease consists of anti-inflammatory medications including ibuprofen (Motrin, Advil) or naproxen (Aleve). These medications can help relieve both the pain and inflammation associated with lumbar disc disease.

A short course of oral corticosteroids, such as prednisone, can also be of benefit, but long-term use of corticosteroids is not recommended. Long-term use is associated with serious side effects, such as peptic ulcer disease, swelling, fluid retention, sleep disturbances, confusion or mood changes, and an increased risk of osteoporosis. For lumbar disc disease that causes severe, radiating nerve pain down the leg (sciatica), epidural injection of corticosteroids may be considered to provide a more prompt anti-inflammatory effect.

Muscle relaxants, such as cyclobenzaprine (Flexeril), can provide short-term relief for many people. These medications can cause drowsiness and should not be used if driving, working, or consuming alcohol. Additional side effects of muscle relaxants include dry mouth, blurred vision, urine retention, and constipation.

Medications that contain narcotic pain relievers, such as codeine, morphine, or oxycodone can also provide relief of the pain associated with lumbar disc disease. These medications should not be continuously administered for chronic pain if alternative treatments can be used. Common side effects include drowsiness, constipation, or nightmares. Caution is advised to take only as prescribed to avoid the toxicity of the narcotic or other medications, such as acetaminophen (Tylenol), that narcotic pain relievers may contain.

Surgery

Surgery is an option for the treatment of lumbar disc disease in people who do not respond to the conservative treatment options discussed in "Medications."

Surgical options include lumbar decompression, lumbar fusion, and lumbar disc replacement.

Lumbar decompression involves removing a portion of the bone from the back of the spinal column to increase the space available for the nerves exiting the spinal cord. This can relieve the pressure on the nerves and relieve the associated pain. This option should not be used if there is any excessive motion in the spine due to instability. Imaging studies can be ordered by a surgeon to assess for signs of instability.

There are several types of lumbar fusion. The lumbar spine can be approached from either the front through the abdomen, through the back, or both. This decision is made by the surgeon based on findings from the preoperative analysis. In many cases, the surgeon removes most of the intervertebral disc and replaces it with either bone or another material. In many cases of lumbar disc disease, the disc is a major source of pain. Once removed, the pain is significantly relieved. After removing the disc, the motion segment becomes unstable and has too much available motion. The fusion is performed to help the two vertebrae grow together and remove any motion between them. The choice of whether or not to use instrumentation or metal screws and rods to stabilize the spine is made by the surgeon based on findings from the exam and imaging studies.

A new option for the treatment of lumbar disc disease is lumbar disc replacement. This technique involves removing all of the intervertebral discs as in a spinal fusion, but instead of replacing the disc with bone, an artificial disc is inserted. The advantage of this technique is the person is able to retain close to normal motion at the level of surgery. It is thought that this will lessen the chance of developing further degenerative changes at the neighboring levels in the spine over time. This technique can only be used in cases of isolated disc disease. If people have arthritis in the facet joints of the spine, disc replacement is not indicated.

Other Therapy

Many people with lumbar disc disease can benefit from a structured program of physical therapy. This can assist with both strengthening of the abdominal and lower back muscles as well as overall conditioning of the body.

People can be taught specific exercises that can be continued at home after the organized therapy program is completed.

Physical therapists have many different modalities at their disposal to assist in the treatment of lumbar disc disease. These include heat, massage, electrical stimulation of muscles, ultrasound therapy, and water therapy.

Follow-up

Most cases of low back pain resolve spontaneously over several weeks. People who do not improve should continue to follow up with the doctor to see if further imaging or laboratory studies are necessary.

Prevention

The best method to prevent lumbar disc disease is to maintain adequate conditioning and muscle strength. Use proper lifting mechanics and do not lift heavy objects using the lower back muscles as this places unnecessary stress on the back.

Many cases of lumbar disc disease cannot be prevented because it results from a combination of normal degenerative changes that occur with aging and a genetic predisposition.

Outlook

The outlook for patients with lumbar disc disease is very positive. New advancements in surgical treatments, including lumbar disc replacement, provide a new tool for surgeons to treat this disorder with less risk of altering the normal mechanical environment of the spine.

Support Groups and Counseling

Degenerative Disc Disease Support Group