A critical appraisal of the evidence for selective nerve root injection in the treatment of lumbosacral radiculopathy

Objective: To critically review the best available trials of the utility of transforaminal epidural steroid injections (TFESIs) or selective nerve root blocks (SNRBs) to treat lumbosacral radiculopathy. Data Sources: MEDLINE (PubMed, Ovid, MDConsult), EMBASE, and the Cochrane database. Databases were searched from inception through 2003. Study Selection: A database search was conducted by using the following key words: prospective, transforaminal and foraminal epidural steroid injections, selective nerve root block and injection, and periradicular and nerve root injection. We included English-language, prospective, randomized studies of patients with lower-limb radicular symptoms treated with fluoroscopically guided nerve root or transforaminal epidural injections. Data Extraction: Data were compiled for each of the following categories: inclusion criteria, randomization protocol, total number of subjects enrolled initially and at final analysis, statistical analysis utilized, documentation of technique, outcome measures, follow-up intervals and results (positive or negative), and reported complications. These data were abstracted by I reviewer and reviewed by a second. Study quality was assessed with the system developed by the Agency for Health Care and Policy Research. Data Synthesis: We selected 6 articles for review. Our analysis identified a single article as the highest quality study addressing the appropriate use of TFESIs or therapeutic SNRBs. Coupled with the evidence provided by 4 other articles (1 article was excluded because its patients were not truly randomized), our review of the evidence for TFESIs found level III (moderate) evidence in support of these minimally invasive and safe procedures in treating painful radicular symptoms. However, conclusive evidence (level 1) is lacking. Conclusions: The evidence for TFESIs reveals level III (moderate) evidence in support of these minimally invasive and safe procedures in treating painful lumbar radicular symptoms. Current studies support use of TFESIs as a safe and minimally invasive adjunct treatment for lumbar radicular symptoms. However, more prospective, randomized, placebo-controlled studies using sham procedures are needed to provide conclusive evidence for the efficacy of TFESIs in treating lumbar radicular symptoms.