Low back pain
From the June ACP Observer, copyright © 2006 by the American College of Physicians.
After colds and flu, low back pain is the most common reason patients visit primary care physicians. But these visits can be a frustrating experience for patients, who expect to get relief, help and guidance from the encounter.
Experts say that physicians can help patients by carefully explaining the condition’s natural progression and what patients can do to prevent a recurrence.
Just reassuring patients that their back pain “may have come on suddenly, but it ends gradually over a few days or weeks” can help patients decide to tough it out or to seek physical therapy, a chiropractor or even massage during recuperation, explained Steven J. Atlas, ACP Member, assistant professor of medicine at Harvard Medical School, associate physician in general medicine at Boston's Massachusetts General Hospital and editorial consultant for the PIER module on low back pain.
Physicians can also help patients by considering an episode of back pain as a prompt to advise them about weight control and cardiovascular exercise. Both of those strategies have a much better chance of warding off future bouts of back pain than many of the interventions patients choose, from medicines to regular chiropractic adjustments.
“That acute episode should be a flag that the next time you see them, you should talk about lifestyle, activity, weight and exercise to prevent the next episode," Dr. Atlas said. "Make them aware that there are things they can do to decrease how frequently these episodes happen—and how severe they are when they do.”
This edition of ACP Observer Special Focus is designed to help optimize your ability to diagnose, treat and manage patients with low back pain.
Nearly 70% of adults will experience low back pain sometime in their lifetime. Although no specific intervention will prevent the problem, physicians should stress fitness and recommend regular aerobic exercise to all patients to decrease their chance of experiencing back pain.
For most back pain, it is hard to be certain about the cause—and even identifiable anatomic abnormalities may have nothing to do with current pain. In most cases, low back pain does not have a clearly identifiable cause.
Colored X-ray showing lateral view of the lumbosacral spine. In most patients with acute back pain, imaging studies are likely to be normal and should be ordered only selectively.
In rare situations, however, back pain may be a symptom of underlying systemic disease. Take a history to rule out the following:
- cancer, typically metastatic tumor (less than 1% prevalence);
- infection (0.01% prevalence);
- acute compression fracture (4% prevalence); or
- ankylosing spondylitis (0.3% prevalence).
Clues that low back pain may be a sign of cancer include a previous history of cancer, unexplained weight loss, no relief with bed rest, pain that lasts more than a month or that has not improved with a month of therapy, and increasing age.
To screen for ankylosing spondylitis, ask these questions and follow up if there are four or more positive answers:
- Is there morning stiffness?
- Does the discomfort decrease with exercise?
- Was the onset of back pain before age 40?
- Did the problem begin slowly?
- Has the pain persisted for at least three months?
Suspect compression fractures if a patient is older or Caucasian, has experienced trauma, or has used corticosteroids for a prolonged period.
Associate spinal osteomyelitis with intravenous drug use or a urinary tract infection. And worry about nerve root involvement if a patient has leg pain in addition to—or more severe than—back pain, or if pain radiates from the back through the buttocks into the lower legs.
During your history, ask about job dissatisfaction, depression, substance abuse, and the patient's desire for disability compensation or litigation. Because psychosocial distress is the most important predictor of what course acute or chronic back pain will follow, look for the following behavioral symptoms and signs:
- reports of pain at the tip of the tailbone, whole leg pain or numbness, or never being pain-free;
- intolerance or reactions to many treatments or hospital emergency visits for uncomplicated back pain;
- whole leg giving way and at other times working normally;
- superficial tenderness to light pinch over the lumbar area or nonanatomic tenderness;
- increase in pain on axial loading when applying a few pounds of hand pressure to the top of the patient’s skull or when there is simulated rotation of the spine;
- discrepancy in straight leg raises during distraction; and
- regional weakness and sensory change that does not fit an anatomic distribution.
Consider using a validated instrument to assess pain and function and judge response to therapy. The most common tools used for back pain are the Roland-Morris modification of the Sickness Impact Profile and the Oswestry Disability Index.
As part of the exam, several tests can help:
- A straight-leg raise test. A herniated disk typically will cause pain radiating distal to the knee at an angle somewhat less than 60 degrees.
- A crossed straight-leg raise test that causes radiating pain in the opposite leg is not sensitive but reasonably specific for a herniated disk.
- Check for ankle weakness and loss of ankle reflex, toe dorsiflexors and sensory loss in the feet.
Look for indications that would prompt the need for lumbosacral radiography, advanced imaging or referral to a specialist. The absence of any history or physical indications of systemic disease is a highly sensitive way to exclude patients from further follow-up. (See "Low back pain: other conditions to consider.")
Order two-view X-rays only for patients with potentially serious underlying systemic illness or fracture. Order CT and MRI only when evaluating patients for diskitis, infection, cord compression or cauda equina syndrome, or with disk herniation when surgery is contemplated.
Negative lumbosacral X-rays do not exclude disease in someone at high risk for cancer; refer such patients to a specialist. If you suspect spinal stenosis, consider advanced imaging studies or vascular studies to distinguish it from vascular claudication.
Reserve electromyography and nerve conduction velocity tests for patients in whom there is diagnostic uncertainty about the relationship of leg symptoms to anatomic findings on advanced imaging studies.
Call for urgent surgical consultation by an orthopedic surgeon, neurosurgeon or emergency department if there is clinical evidence of neurologic compromise at the level of the upper motor neuron, spinal cord compression at the level of the lower motor neuron or compression of the cauda equina. Common signs include bowel or bladder sphincter dysfunction, diminished sensation in the perineal region, and severe and progressive unilateral or bilateral motor deficits.
In patients under age 50, lumbar disk herniations are the most likely cause of nerve involvement (usually at either L4-5 or L5-S1); in older patients, consider spinal stenosis. Many of these patients with chronic stable signs and symptoms do not require urgent surgical consultation.
Recognize that most acute nonspecific pain improves over time without the need for treatment. Educate the many patients who believe that back pain is the first sign of what will become a crippling and disabling condition that just the opposite is true.
Because prolonged inactivity is associated with worse outcomes for patients with low back pain, encourage patients to continue normal activities as soon and as much as they can.
And explain that general physical fitness may help prevent recurrences—but discourage patients from starting back exercises immediately, while they are in acute pain. That may delay recovery.
Little evidence exists to recommend one exercise program over another, but consider referring patients for physical treatments—such as spinal manipulation or physical therapy not to exceed 12 sessions over four weeks—if their acute symptoms have not improved after one to two weeks.
For patients with chronic low back pain, consider multidisciplinary treatment programs including back exercises, physical treatments and behavioral therapy. Focus on function rather than on only pain relief. Avoid further diagnostic testing because "medicalizing” back pain can result in worse patient outcomes.
Drug therapy and hospitalization
Simple analgesics, including acetaminophen or nonsteroidal anti-inflammatory agents (NSAIDs), should be the first line of analgesic therapy. Muscle relaxants and short courses of opioids work, but neither have been shown to be more effective than acetaminophen or NSAIDs—and both have more side effects.
There is conflicting evidence about the role of antidepressants in treating chronic low back pain. Tricyclic antidepressants, which inhibit norepinephrine reuptake, may improve symptoms, while selective serotonin reuptake inhibitors do not.
Hospitalization is rarely necessary because both bed rest and traction are ineffective. Hospitalization is necessary, however, for patients who may have a serious underlying cause of their back pain or face imminent loss of neurologic function.
Patients who have not responded to conservative therapy after one month have a poorer prognosis than other patients. Consider referring these individuals to a rheumatologist, neurologist, occupational medicine specialist, physical medicine and rehabilitation therapist, or pain specialist.
Refer patients with severe radicular symptoms who do not respond to conservative therapy and who are willing to consider surgery to an orthopedic surgeon or neurosurgeon.
If patients exhibit depression, substance abuse, job dissatisfaction or other psychosocial problems, consider an early referral to psychiatric, behavioral or occupational therapists. Keep in mind that psychosocial distress is the most important marker of poor prognosis—and that cognitive-behavioral therapies for low back pain show good short-term results.
Reassure patients that back pain is common, recurrences are usual and that between 50% and 75% of people experience gradual improvement over four weeks, and most have minimal symptoms after six months. Tell them that most people do not need surgery, even if they have herniated disks.
Patients with chronic low back pain have reported significant improvement in functional outcomes and health care use after a progressive exercise program supervised by a physical therapist. Inform patients with psychosocial factors that psychiatric, behavioral or occupational therapy may help.
Follow up on symptoms and on treatment response with an office visit or telephone call after two to four weeks. If recovery is delayed, consider reevaluation for possible underlying causes or possible psychosocial factors.
|This information comes from two PIER modules: "Low Back Pain" and "Back Pain (Complementary/ Alternative Medicine)."|
The information included herein should never be used as a substitute for clinical judgment and does not represent an official position of ACP.
When it comes to complementary and alternative treatments, listen to patient preferences. Although there is no specific intervention that is most effective in treating low back pain, there is some evidence favoring the following treatments:
Spinal manipulation. Use eight to 12 treatments over one month. In cases of clinically significant improvement, continue at a reduced frequency until reaching maximum improvement. Caution patients with tumors, osteopenia or osteoporosis, active inflammatory arthritis, long-term steroid use, or anticoagulant use to avoid high velocity or thrusting spinal manipulation. Instead identify chiropractors, osteopaths and physical therapists who provide nonthrusting forms of manual therapy.
Massage therapy. Administer between six and 10 treatments over four-six weeks. Massage therapy may be more effective when used in conjunction with therapeutic exercise and posture education. Avoid in patients with phlebitis, deep venous thrombosis, advanced osteoporosis, local burns, skin infection, open wounds, fractures, history of sexual assaults and difficulty with close physical contact.
Acupuncture. Consider six-10 treatments over four-eight weeks for chronic low back pain that has not responded to standard therapies.
Willow bark extract (salicin). Consider recommending a dose of 120-240 mg once per day—and caution patients that they need to continue therapy for up to one week before seeing any benefit. Avoid in patients with aspirin sensitivity or allergy, current gastrointestinal ulceration, or in those taking anticoagulants.
Devil’s claw (Harpagophytum procumbens extract). Daily dose is 50-100 mg of harpagoside (6,000 mg of crude preparation equals 50 mg of harpagoside). Side effects include occasional gastrointestinal upset.
Preliminary but incomplete data suggests a possible role for the following treatments in conjunction with other therapies: topical application of the homeopathic gel Spiroflor SRL; chondroitin sulfate (up to 1,200mg/d) when chronic low back pain is associated with degenerative spinal disease; and short-term courses (six-10 treatments over four-eight weeks) of acupressure/acupuncture massage.
And advise patients that there is no evidence of benefit from these treatments: glucosamine sulfate; bipolar, permanent magnets; Rolfing; the Feldenkrais Method; and yoga.
However, results of a study published in the Dec. 20, 2005 issue of Annals of Internal Medicine found that a 12-week course of weekly yoga classes did help—under carefully supervised conditions. The course, run at the Group Health Cooperative in Seattle, was designed specifically for people with back pain who did not have previous yoga experience.
Researchers found that the yoga classes helped people more than a regular therapeutic exercise class or giving people a self-care book. During the 12-week period, only 11% of the yoga participants reported visiting health care providers for low-back pain, compared with 23% in the exercise group.
Degenerative joint disease: Common radiologic abnormality that may or may not be related to symptoms.
Degenerative disk disease with herniation: Common cause of nerve root impingement and radicular symptoms.
Spinal stenosis: Most common in elderly presenting with severe leg pain and pseudoclaudication.
Ankylosing spondylitis or other axial spondyloarthropathy: Usual onset before age 40 with decreased spinal range of motion. Associated signs and symptoms depending on type of spondyloarthropathy.
Osteomyelitis/spinal abscess: Probably previous or ongoing source of infection with constitutional symptoms.
Tumors arising in the spine or surrounding structures, or metastases from distant primary site: Metastatic disease commonly from prostate, breast and lung cancer; can cause cord compression.
Intraabdominal visceral disease: Gastrointestinal: peptic ulcer, pancreatitis. Genitourinary: nephrolithiasis, pyelonephritis, prostatitis, pelvic infection or tumor. Vascular: aortic dissection. All of these illnesses can cause back pain.
Metabolic bone disease with or without compression fracture: Best example is osteoporosis with compression fracture.
Herpes zoster: Unilateral dermatomal rash. The onset of pain can precede the appearance of the rash.
Psychosocial distress: An exacerbating factor that may delay recovery.
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