Can a nerve stimulator stop my back pain?

Every weekday, a CNNHealth expert doctor answers a viewer question. On Wednesday, it's Dr. Otis Brawley, chief medical officer for the American Cancer Society.

Question asked by Larry of New York

I have had severe, chronic back and sciatic pain for many years. My particular problems cannot be resolved surgically. Nerve blocks and other minimally invasive procedures have been partially successful in temporarily reducing the pain.
Medications have reduced my back pain, but the sciatic pain continues to be severe. My pain specialist has suggested an implantable nerve stimulator for the sciatic nerve. How successful are these devices?

Expert answer

Dear Larry,

I consulted several physiatrists (nerve, muscle, and bone experts who treat injuries or illnesses that affect movement) and neurologists with extensive experience in the treatment of chronic low back pain and pain radiating down the sciatic nerve of the leg in order to answer your question.

They stress that almost all adults have low back pain at some time in their lives and the outcomes are good with the pain going away for most within three months.

Acute low back pain is defined as lasting less than four weeks. Sub-acute low back pain is commonly defined as back pain lasting between four and 12 weeks and chronic low back pain persists for 12 or more weeks.

The health care provider will initially evaluate the patient with low back pain by getting a history of the pain and doing a targeted physical examination. The exam focuses on excluding serious neurologic problems such as malignancy or infection.

Causes of back pain include compression of the bone around nerves as they leave the spine. This is often due to arthritic degeneration and commonly feels like a pain running down the nerve path. Sciatica falls into this class.

Other common causes of chronic low back pain are spinal stenosis, a condition in which the spinal cord is squeezed by the arthritic spinal bones; ankylosing spondylitis, in which the ligaments of the spine are inflamed and the spine is stiff; and fracture of a spinal vertebral bone.

Most patients will end up with nonspecific low back pain of unknown origin. The treatment of all nonspecific low back pain is with non-narcotic pain medications and physical therapy. Most health care providers will not do extensive radiological and neurologic tests on a patient until the pain has persisted for more than four weeks despite treatment.

When symptoms of nonspecific low back pain persist more than three months, the goal of treatment moves from "cure" to controlling pain, maintaining function and preventing disability.

Studies show that many patients with chronic low back pain do not receive evidence-based care.

Too often, there is overuse of unproven interventions (such as traction and corsets), over-reliance on opioids and muscle relaxants and underuse of exercise therapy.

Injection of nerve roots with steroids or numbing medications (nerve blocks) generally provide short-term relief and can be done only when the source of the pain is identifiable.

The experts gave the following recommendations for patients with chronic low back pain.

The patient should try to remain active and limit bed rest.

Engaging in supervised exercise therapy that includes stretching and strengthening is an important part of therapy, as is some aerobic activity

Consider yoga, spinal manipulation, massage therapy, cognitive behavioral therapy and acupuncture.

Do not use lumbar supports.

Use nonopioid analgesics such as acetaminophen or nonsteroidal anti-inflammatory drugs.

Only the most severely disabled, with a low vulnerability for drug abuse, should use opioids. Opioids should then be used sparingly for acute exacerbations of back pain.

Avoid use of anti-epileptic medications, muscle relaxants and benzodiazepines such as valium for long-term low back pain.

A nerve generates an electrical signal. In sensory nerves, these signals may communicate pain to the brain. A nerve stimulator is used to cancel out the electrical pain signals in the nerve. The peripheral nerve stimulator is implanted under the skin and is placed to send electrical pulses to the problematic nerve directly.

A very few patients do get relief with implantable nerve stimulators and other treatments such as interferential therapy, low level laser therapy, short-wave diathermy, traction, transcutaneous electrical nerve stimulation (TENS), ultrasound or percutaneous electrical nerve stimulation (PENS).

These treatments are worth a try for people who have not gotten adequate relief from other more established treatments. All the experts I consulted noted that treatment of chronic low back pain is often frustrating and patients going through the experience often develop clinical depression.

They suggested that health care providers and patients be on the lookout for depression and they suggest that it be treated aggressively with antidepressants.

They also said it is important for the patient to continue working with his or her doctor to find a source of relief.