Therapeutic nerve blocks for chronic pain.
Nerve blocks are an effective treatment in patients with many types of acute pain. However, they are much less effective in patients with chronic pain. Candidates for therapeutic nerve blocks should be carefully screened by: assessment of organic disease; evaluation of psychologic and behavioral disorders, and differential nerve blocks. The best candidates for therapeutic nerve blocks have known or inferred organic disease, minimal psychologic or behavioral disorders, and evidence of sympathetic or somatic pain mechanisms.