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

Low-income populations have a lower prevalence of low back pain than high-income populations. Pathologic processes affecting the intervertebral disc are affected by genetic factors and degeneration of annular fibers. Historical and physical findings are not helpful in identifying damaged tissues in patients with nonspecific low back pain. Agency for Health Care Policy and Research guidelines for plain radiographs in the evaluation of low back pain are too sensitive and expose patients unnecessarily to ionizing radiation. Clinical entities reviewed in the literature include septic sacroiliitis, prognosis of metastatic spinal tumors, and low back pain in health care professionals. Epidural corticosteroid injections are useful for leg pain and sensory deficits early in the course of sciatica secondary to a herniated nucleus pulposus. Poor nutritional state increases the risk for postoperative infections for spinal fusion patients.