STUDY DESIGN: Prospective, double-blind, randomized, case-control study.OBJECTIVE: To evaluate the efficacy of caudal epidural injections (CEI) containing steroid versus nonsteroid preparations when treating patients suffering from low back pain (LBP) and sciatica.SUMMARY OF BACKGROUND DATA: Literature seems to be deprived of well-designed randomized, controlled studies that evaluate the effectiveness of CEI in the treatment of chronic LBP; hence the value of CEI remains still the subject of controversy.METHODS: Patients suffering from severe chronic LBP and sciatica were randomly allocated into 2 groups. Steroid-group's patients (n = 93) underwent CEI containing 12 mL of xylocaine 2% and 1 mL of betamethasone dipropionate and betamethasone phosphate (2 + 5) mg/dL. Water for Injection (WFI)-group's patients (n = 90) underwent CEI containing 12 mL of xylocaine 2% and 8 mL of WFI. Both groups were statistically comparable as far as their demographic data and the cause and duration of symptoms were concerned. Patients answered the Oswestry Disability Index questionnaire and underwent physical examination, before and at 1 week, 1 month, 6 months, and 1 year following the CEI.RESULTS: Symptoms improved in 132 patients (72.1%) following CEI. The mean Oswestry Disability Index questionnaire score of steroid-group's patients was statistically significant lower than that of the WFI-group at all postinjection re-evaluations. Patients receiving steroid CEI experienced faster relief during the first postinjection week. The Straight Leg Rising test improved in both groups following CEI; this improvement was faster among steroid-group's patients. Fifty-one patients (27.8%), noticed no improvement 1 week post-CEI and underwent a second CEI (with the same preparation) 7 to 14 days later. Nineteen of them reported improvement; 32 (steroid-group:13, WFI-group:19) did not respond well and underwent operative decompression (n = 15) or spinal fusion (n = 17).CONCLUSION: CEI containing local anesthetic and steroids or WFI seems to be effective when treating patients with LBP and sciatica. CEI containing steroid preparations demonstrated better and faster efficacy.