Systematic review of caudal epidural injections in the management of chronic low back pain.

BACKGROUND Caudal epidural injection of local anesthetics with or without steroids is one of the most commonly used interventions in managing chronic low back and lower extremity pain. However, there has been a lack of well-designed randomized, controlled studies to determine the effectiveness of caudal epidural injections in various conditions - disc herniation and radiculitis, post-lumbar laminectomy syndrome, spinal stenosis, and chronic low back pain of disc origin without disc herniation or radiculitis. STUDY DESIGN A systematic review of caudal epidural injections with or without steroids in managing chronic pain secondary to lumbar disc herniation or radiculitis, post lumbar laminectomy syndrome, spinal stenosis, and discogenic pain without disc herniation or radiculitis. OBJECTIVE To evaluate the effect of caudal epidural injections with or without steroids in managing various types of chronic low back and lower extremity pain emanating as a result of disc herniation or radiculitis, post-lumbar laminectomy syndrome, spinal stenosis, and chronic discogenic pain. METHODS A review of the literature was performed according to the Cochrane Musculoskeletal Review Group Criteria as utilized for interventional techniques for randomized trials and the Agency for Healthcare Research and Quality (AHRQ) criteria for observational studies. The level of evidence was classified as Level I, II, or III based on the quality of evidence developed by the U.S. Preventive Services Task Force (USPSTF). Data sources included relevant literature of the English language identified through searches of PubMed and EMBASE from 1966 to November 2008, and manual searches of bibliographies of known primary and review articles. OUTCOME MEASURES The primary outcome measure was pain relief (short-term relief = up to 6 months and long-term > or = 6 months). Secondary outcome measures of improvement in functional status, psychological status, return to work, and reduction in opioid intake were utilized. RESULTS The evidence showed Level I for short- and long-term relief in managing chronic low back and lower extremity pain secondary to lumbar disc herniation and/or radiculitis and discogenic pain without disc herniation or radiculitis. The indicated evidence is Level II-1 or II-2 for caudal epidural injections in managing low back pain of post-lumbar laminectomy syndrome and spinal stenosis. LIMITATIONS The limitations of this study include the paucity of literature, specifically for chronic pain without disc herniation. CONCLUSION This systematic review shows Level I evidence for relief of chronic pain secondary to disc herniation or radiculitis and discogenic pain without disc herniation or radiculitis. Further, the indicated evidence is Level II-1 or II-2 for caudal epidural injections in managing chronic pain of post lumbar laminectomy syndrome and spinal stenosis.