Degenerative Disc Disease of the Lumbar Spine

Degenerative Disc Disease (DDD) is a gradual process that may compromise the spine. Although DDD is relatively common, its effects are usually not severe enough to warrant medical attention. In this discussion we address Degenerative Disc Disease in the lumbar spine.

Degenerative Changes to a Disc

Degenerative changes in the spine are often referred to those that cause the loss of normal structure and/or function. The intervertebral disc is one structure prone to the degenerative changes associated with wear and tear aging, even misuse (e.g. smoking).

Long before Degenerative Disc Disease can be seen radiographically, biochemical and histologic (structural) changes occur. Some of these changes are not unlike those associated with osteoarthritis.

Over time the collagen (protein) structure of the annulus fibrosus weakens and may become structurally unsound. Additionally, water and proteoglycan (PG) content decreases. PGs are molecules that attract water. These changes are linked and may lead to the disc’s inability to handle mechanical stress. Understanding the lumbar spine carries a large portion of the body’s weight; the stress from motion may result in a disc problem (e.g. herniation).

Non-Operative Treatment: Yesterday vs. Today

DDD is a disorder that may cause low back pain. It is interesting to note that although 80% of adults will experience back pain, only 1-2% will need lumbar spine surgery!

In the past some physicians prescribed long courses of bedrest and/or lumbar traction for their patients with low back pain. However, that is not the attitude today. During the acute phase, bedrest may be recommended for a few days, but beyond that experts advocate stretching, flexion and extension exercises, and no/low impact aerobics. Of course, each patient is different and therefore so is their treatment plan.

Therapeutic Exercise

In some patients, the pain response may limit their flexibility. Prescribed stretching exercises can improve flexibility of the trunk muscles. Flexion exercises may help to widen the intervertebral foramen. The intervertebral (between the vertebrae) foramen are small canals through which the nerve roots exit the spinal cord. The intervertebral foramen are located on the left and right sides of the spinal column.

Extension exercises, such as the McKenzie method, focuses on the muscles and ligaments. These exercises help maintain the spine’s natural lordotic curve, important to good .

Aerobics (no/low impact) offers many benefits including improved muscular endurance, coordination, strength, strong abdominal muscles, and weight loss. Strong abdominal muscles work like a brace (or corset) to reduce the loads to the lumbar spine. It is also known that aerobics help to combat anxiety and depression. The loads on the discs during walking are only slightly greater than when lying down. Walking, bicycling, and swimming are forms of aerobic exercise a physician may suggest.

Acupuncture

Acupuncture, a type of alternative medicine, has been shown to control pain. It has been suggested that acupuncture stimulates the production of endorphins, acetylcholine, and serotonin. However, acupuncture should be combined with an exercise program for many of the reasons outlined in prior paragraphs.

Drug Therapy

During the acute phase of low back pain, drugs may be prescribed. Some of these may include narcotics, acetaminophen, anti-inflammatory agents, muscle relaxants, and anti-depressants. Narcotics are used on a short-term basis partially due to their addiction potential. When low back pain is caused by muscle spasm, a muscle relaxant may be prescribed. These drugs have sedative effects. Depression can be a factor in chronic low back pain. Anti-depressant drugs have analgesic properties and may improve sleep.

Manipulation

Today manipulation is performed by Chiropractors and Physical Therapists. For patients without radiculopathy (pain stemming from a spinal nerve root), manipulation may be effective during the first month. Thereafter, benefits are unproven. Manipulation is believed to be effective because of its effect on spinal mobility. Acute low back pain, chronic low back pain, and DDD without nerve compression may respond to manipulation.

The First Six Weeks

Usually during the first six weeks, acute low back pain is treated with a couple of days of bedrest (slightly longer with herniated disc) and appropriate medication. Muscle relaxants are seldom used for longer than one week. Early ambulation is encouraged to increase circulation (aids healing), improve flexibility, and build strength.

Generally, during the first two to three weeks the acute symptoms subside. Aerobic (no/low impact) exercise may be started three times per week along with daily back exercises. Some patients may be referred to physical therapy or a supervised work-conditioning program.

Beyond Six Weeks

If the symptoms of DDD and low back pain persist despite non-operative treatment, further diagnostic tests may be necessary. These tests may include an MRI, CT Scan, Myelogram, or possibly Discography.

Although most DDD patients with herniation respond well to non-operative treatments, a small percentage do not. Disc herniation is the most common indication for spinal surgery. In fact, 75% of all spinal surgeries are for a herniated disc.

Red Flags

Lumbar herniation causing loss of bowel or bladder control, or major lower extremity deficit, requires immediate surgery. These symptoms (Red Flags) are caused by nerve root compression. Cauda Equina Syndrome is a serious disorder that may be caused by a large central herniation. The cauda equina begins at the end of the spinal cord. The cauda sac is filled with nerves resembling the tail of a horse. When this sac is compressed the patient may present with the following symptoms: low back pain, bilateral lower extremity weakness, radiculopathy (pain from a nerve root), and incontinence.

When these symptoms present, surgery is required immediately. Most herniated discs often do not require surgical intervention and respond quite nicely to non-surgical treatments (within 6 weeks).

Surgical Procedures

The type of surgical procedure(s) is dependent on the patient, the diagnosis, and the goals of surgery.

Surgical removal of an inferior disc may involve a limited laminotomy and partial disc excision. The disc fragments are removed and the nerve is decompressed. Micro-discectomy is often a preferred procedure requiring smaller incisions resulting in reduced scarring and a more rapid recovery.

If the entire disc is removed, spinal column instability may warrant fusion. Patients who are obese, smoke, or who have psychological problems exhibit lower rates of success. Smoking in particular negatively impacts the process of fusion and healing in general. Spinal fusion may be combined with spinal instrumentation, the use of medically designed hardware (e.g. screws, cages).

In Conclusion

Although degenerative disc disease is relatively common in aging adults, it seldom means a surgical sentence. When medical attention is warranted, the majority of patients respond well to non-operative forms of treatment. By eliminating tobacco and maintaining a fitness regiment along with a good diet, most people can enjoy the benefits of a healthy spine.


Links for Research ... Updated Periodically.

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SpineUniverse

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