Purpose: The purpose of this brief narrative review is to summarize the evidence derived from randomized controlled trials pertaining to the nonsurgical treatment of lumbar spinal stenosis (LSS).
Source: The MEDLINE (January 1950 to the fourth week of January 2010) and EMBASE (January 1980 to 2009, week 53) databases, the MESH term "spinal stenosis", and the key words, "vertebral canal stenosis" and "neurogenic claudication", were searched. Results were limited to randomized controlled trials (RCTs) conducted on human subjects, written in English, and published in peer-reviewed journals. Only RCTs pertaining to nonsurgical treatment were considered. Studies comparing conservative and surgical management or different surgical techniques were not included in the review.
Principal findings: The search criteria yielded 13 RCTs. The average enrolment was 54 subjects per study. Blinded assessment and sample size justification were provided in 85% and 39% of RCTs, respectively. The available evidence suggests that parenteral calcitonin, but not intranasal calcitonin, can transiently decrease pain in patients with LSS. In the setting of epidural blocks, local anesthetics can improve pain and function, but the benefits seem short-lived. The available evidence does not support the addition of steroids to local anesthetic agents. Based on the limited evidence, passive physical therapy seems to provide minimal benefits in LSS. The optimal regimen for active physiotherapy remains unknown. Although benefits have been reported with gabapentin, limaprost, methylcobalamin, and epidural adhesiolysis, further trials are required to validate these findings.
Conclusions: Because of their variable quality, published RCTs can provide only limited evidence to formulate recommendations pertaining to the nonsurgical treatment of LSS. In this narrative review, no study was excluded based on factors such as sample size justification, statistical power, blinding, definition of intervention allocation, or clinical outcomes. This aspect may represent a limitation as it may serve to overemphasize evidence derived from "weaker" trials. Further well-designed RCTs are warranted.