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Low back pain (chronic).

Volume 84, Number 4 www.aafp.org/afp American Family Physician 437 More than 70 percent of persons in developed countries will experience low back pain at some time, which usually improves within two weeks; however, about 10 percent remain unable to work and about 20 percent have persistent symptoms at one year. Nonsteroidal anti-inf lammatory drugs may be more effective than placebo at improving pain intensity in persons with chronic low back pain. Opioid analgesics (with or without paracetamol) may improve pain and function compared with placebo. However, longterm use of nonsteroidal anti-inflammatory drugs or opioids may be associated with well-recognized adverse effects. • We do not know whether antidepressants decrease chronic low back pain or improve function compared with placebo in persons with or without depression. • Benzodiazepines may improve pain, but studies of nonbenzodiazepine muscle relaxants have given conflicting results. Caution: Since the last update of this review, a drug safety alert has been issued on increased suicidal behavior with antidepressants (http://www.fda.gov/medwatch). We do not know whether epidural corticosteroid injections or local injections with corticosteroids and local anesthetic improve chronic low back pain in persons without leg pain (sciatica). • Facet joint corticosteroid injections may be no more effective than placebo at reducing pain. Fusion surgery is more effective than standard rehabilitation for improving pain in persons with chronic nonradicular low back pain, but it is no better than intensive rehabilitation with a cognitive behavioral component. Exercise improves pain and function compared with other conservative treatments. Intensive multidisciplinary treatment programs improve pain and function compared with usual care, but less-intensive programs do not seem beneficial. Acupuncture, back schools, behavioral therapy, and spinal manipulation may reduce pain in the short term, but effects on function are unclear. Massage may improve pain and function compared with sham or other active treatment. We do not know whether electromyographic biofeedback, lumbar supports, traction, or transcutaneous electrical neural stimulation improve pain relief. We also do not know whether intra discal electrothermal therapy, radiofrequency denervation, or disk replacement improves pain relief or function.