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Subacute and chronic low back pain: Pharmacologic and noninterventional treatment

Author
Roger Chou, MD
Section Editor
Steven J Atlas, MD, MPH
Deputy Editor
H Nancy Sokol, MD

INTRODUCTION

Up to 84 percent of adults have low back pain at some time in their lives [1,2]. The long-term outcome of low back pain is generally favorable. In one prospective study, 90 percent of patients with low back pain seen initially in primary care did not seek care after three months [3]. However, given how common low back pain is, persistent symptoms affect millions of individuals. Subacute low back pain is commonly defined as back pain lasting between 4 and 12 weeks and chronic low back pain as pain that persists for 12 or more weeks.

The initial evaluation of patients with low back pain, regardless of its duration, includes history taking and a targeted physical examination focusing on neurologic screening to exclude serious underlying pathology (eg, malignancy, infection, or cauda equina syndrome). On the basis of this evaluation, patients are triaged into broad diagnostic categories that include nonspecific low back pain, radiculopathy, or other specific pathology (eg, spinal stenosis, ankylosing spondylitis, and vertebral compression fracture) [4-6]. (See "Evaluation of low back pain in adults".)

Most patients (>85 percent) who are seen in primary care have "nonspecific low back pain," which is low back pain that cannot reliably be attributed to a specific disease or spinal pathology [7]. Rapid improvement in pain and disability and return to work are the norm in the first month [8]. Patients who do not improve within four weeks of the onset of low back symptoms should be reevaluated and may require further diagnostic testing to identify a specific cause for their symptoms. (See "Evaluation of low back pain in adults", section on 'Risk assessment subacute back pain' and "Evaluation of low back pain in adults", section on 'Risk assessment chronic back pain'.)

Despite persistent pain, patients with subacute symptoms still have a favorable prognosis. For patients whose symptoms persist beyond three months, however, the goal of treatment moves from "cure" to controlling pain, maintaining function, and preventing disability. Factors associated with development of chronic disability include preexisting psychologic conditions, other types of chronic pain, job dissatisfaction or stress, and dispute over compensation issues [9]. Effective methods for reducing the risk of progression to chronic pain have not been definitively identified [10,11].

It is likely that many patients with chronic low back pain are not receiving evidence-based care. One survey of households in North Carolina, for example, identified 732 adults with chronic low back pain [12]. Responses indicated overutilization of unproven interventions (traction, corsets), high use of second-line medications (opioids and muscle relaxants), and underutilization of exercise therapy and, for patients with depression, antidepressants.

                               

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