May 08, 2010
Low Back Pain: Evaluation, Management, and Prognosis
BALTIMORE, Md.—Low back pain is one of the top 10 most common reasons for doctor office visits in the United States; approximately 80% of adults seek care at some time for acute low back pain. The differential diagnosis for low back pain and the importance of identifying clinical red and yellow flags during evaluation was presented at the 29th Annual Scientific Meeting of the American Pain Society. Low back pain should be managed with a comprehensive treatment plan that integrates evidence-based pharmacologic and nonpharmacologic therapies. Frequent monitoring and early identification of patients at high risk for transition to chronic low back pain allows for timely intervention and possible prevention of chronicity of low back pain.
Patients with low back pain are categorized into “three buckets: nonspecific low back pain, back pain potentially associated with radiculopathy, or spinal stenosis, and back pain potentially associated with another specific spinal cause,” stated B. Eliot Cole, MD, MPA, formerly of the American Society of Pain Educators, Montclair, N.J. Clinicians should ask about the location and quality of pain, aggravating or relieving factors, and perform a physical evaluation when conducting a differential diagnosis. Clinical red flags upon physical exam (e.g., fever, hypotension, ashen appearance, spinous process tenderness, focal neurological signs, or acute urinary retention) may be indicative of a more serious underlying etiology. Diagnostic imaging should be obtained only when severe or progressive neurologic deficits are present or when serious underlying conditions are suspected. Magnetic resonance imaging (MRI) or computed tomography (CT) is recommended for severe lower back pain accompanied by signs or symptoms or radiculopathy or spinal stenosis only if the patient is a potential candidate for surgery or epidural steroid injection. There is no compelling evidence that routine imaging affects treatment decisions or improves outcomes.
First-line treatments for low back pain are acetaminophen or non-steroidal anti-inflammatory drugs (NSAIDs). Skeletal muscle relaxants and tricyclic antidepressants also provide moderate benefit in the relief of low back pain. Low back pain management is most effective when pharmacotherapy is provided in conjunction with self-care education and evidence-based information about the expected course of recovery. Roger Chou, MD, FACP, of the Oregon Health & Science University stressed the importance of advising patients to stay active; patients with higher levels of activity achieve pain relief faster and return to work sooner. Noninvasive therapies include behavioral therapy, spinal manipulation, acupuncture, yoga, and massage therapy. Surgery or epidural steroid injections are also interventional options to be considered. Under investigation for the treatment of low back pain are facet joint steroid injection, radiofrequency denervation, and intradiscal electrothermal therapy. These interventions, however, are not supported by sufficient evidence.
Risk factors for chronicity of low back pain include vertebral infection, vertebral compression fracture, inactivity, and emotional distress. Psychosocial risk factors, or yellow flags, of low back pain should be evaluated to predict the patient's risk for developing chronic low back pain. Bill McCarberg, MD, of Kaiser Permanente San Diego, San Diego, Calif., emphasized that of the yellow flags, fear-avoidance of pain, i.e., catastrophizing, has the greatest negative effect on patient recovery. Reducing catastrophizing through an intensive interdisciplinary team intervention consisting of psychology, physical therapy, occupational therapy, and case management lessens the possibility of low back pain chronicity.