Fluoroscopically guided caudal epidural steroid injections for lumbar spinal stenosis: a restrospective evaluation of long term efficacy.

BACKGROUND: Degenerative lumbar spinal stenosis is a frequent cause of disability in the elderly population. Epidural steroid injections are a commonly used conservative modality in the treatment of patients with degenerative lumbar spinal stenosis. Relatively few studies have specifically addressed the efficacy of epidural steroid injections for spinal stenosis, with success rates varying from 20% to 100%.

OBJECTIVE: To assess the efficacy of fluoroscopically guided caudal epidural steroid injections in the management of degenerative lumbar spinal stenosis.

DESIGN: Retrospective chart review and follow-up study.

METHODS: All the patients who had undergone at least one fluoroscopically guided caudal epidural steroid injection between 1995 and 2002 were reviewed. All of the caudal epidural steroid injections were done with fluoroscopic guidance.

MAIN OUTCOME MEASURES: Visual Numeric Scale (VNS), Roland-Morris Disability Questionnaire (RMDQ), North American Spine Society Patient Satisfaction Index (NASS), and subsequent surgery.

RESULTS: Ninety-five patients selected from chart review met inclusion criteria. Eighty (84%) completed the follow-up questionnaire by mail or telephone interview. Patients received an average of 1.6 epidural steroid injections. Twelve patients subsequently underwent surgical procedures. A VNS improvement of 50% or greater was seen in 35% of patients. A functional improvement of 2 points or greater was seen on the RMDQ in 36% of patients. Long-term success of treatment was seen in 35% of patients. The concurrent presence of degenerative spondylolisthesis was the only variable which was found to have a significant positive correlation with successful outcomes (P < 0.009).

CONCLUSION: Caudally placed fluoroscopically guided epidural steroid injections offered a safe, minimally invasive option for managing pain caused by lumbar spinal stenosis. The concurrent presence of degenerative spondylolisthesis appears to be an independent positive prognostic factor for successful outcome.