Placebo response to interventional pain procedures and effect on patient outcome

Abstract

Considerable debate exists over the effectiveness of numerous procedures performed in current interventional pain practice. Our goal was to review all current prospective, randomized, placebo-controlled trials pertaining to the most commonly performed interventional pain procedures and to present these results in the form of a comprehensive review article. A review of the literature was performed with extensive PubMed searches and no date restrictions. A review of various reference sections within articles was also done. All prospective, randomized, placebo-controlled trials acquired that pertained to the most commonly performed intervention pain medicine techniques were included in the review. Lumbar and transforaminal epidural steroid injections appear superior to placebo. Radiofrequency denervation and steroid injections for sacroiliac joint pain appear superior to placebo. Radiofrequency denervation for lumbar and cervical facetogenic pain appears superior to placebo. Intradiscal electrothermal therapy for discogenic low back pain may be more effective than placebo in a select group of patients. Alcohol neurolytic celiac plexus block appears superior to placebo in the treatment of pancreatic cancer pain. Current data do not support superiority over placebo for lumbar facet joint steroid injections, lumbar intradiscal steroid therapy, or vertebroplasty for treatment of osteoporotic fractures. A continued lack of prospective, randomized, placebo-controlled trials pertaining to interventional pain medicine still persists. The above results can only serve as a guide in current practice, as only tentative conclusions can be reached based on the current data.