Epidemiology, etiology, diagnostic evaluation, and treatment of low back pain.

Epidemiologic studies report the prevalence of low back pain to vary from 7.6% to 37% in different populations. Genetic factors play an important role in the development of back pain and intervertebral disk degeneration in adults. An animal model of spinal fusion using osteoinductive growth factors has important implications for surgical spinal fusions in humans. Physical findings have significance in identifying patients with radiculopathy, spinal stenosis, and malingering. Magnetic resonance imaging differentiates metastatic spinal fractures from osteoporotic lesions. Clinical entities reviewed in the literature this year include herniated intervertebral disk-associated radiculopathy, facet joint syndrome, back pain during pregnancy, and spontaneous infectious diskitis. Primary care physicians do not follow published guidelines for treatment of low back pain. Surgical decompression of spinal stenosis is most successful for patients with severe disease.