Fluoroscopic Caudal Epidural Injections in Managing Post Lumbar Surgery Syndrome: Two-Year Results of a Randomized, Double-Blind, Active-Control Trial

STUDY DESIGN A randomized, active control, double-blind trial. OBJECTIVE To evaluate the effectiveness of fluoroscopically directed caudal epidural injections with or without steroids in managing chronic low back and lower extremity pain secondary to post lumbar surgery syndrome. SUMMARY OF BACKGROUND DATA There is a paucity of evidence concerning caudal epidural injections for managing chronic persistent low back pain with or without lower extremity pain caused by post lumbar surgery syndrome. METHODS This active control randomized study included 140 patients with 70 patients in each group. Group I received 0.5% lidocaine, 10 mL; Group II received 9 mL of 0.5% lidocaine mixed with 1 mL of 6 mg of nonparticulate betamethasone. The multiple outcome measures included the numeric rating scale, the Oswestry Disability Index 2.0, employment status, and opioid intake with assessments at 3, 6, 12, 18, and 24 months posttreatment. Primary outcome was defined as at least 50% improvement in pain and Oswestry Disability Index scores. Patients with a positive response to the first 2 procedures with at least 3 weeks of relief were considered to be successful. All others were considered as failures. RESULTS Overall in Group I, 53% and 47% of the patients and in Group II, 59% and 58% of the patients, showed significant improvement with reduction in pain scores and disability index at 12 months and 24 months. In contrast, in the successful groups, significant pain relief and improvement in function were observed in 70% and 62% of Group I at one and 2 years; in 75% and 69% of Group II at one and 2 years. The results in the successful group showed that at the end of the first year patients experienced approximately 38 weeks of relief and at the end of 2 years Group I had 62 weeks and Group II had 68 weeks of relief. Overall total relief for 2 years was 48 weeks in Group I and 54 weeks in Group II. The average procedures in the successful groups were at 4 in one year and 6 at the end of 2 years. CONCLUSION Caudal epidural injections of local anesthetic with or without steroid might be effective in patients with chronic persistent low back and/or lower extremity pain in patients with post lumbar surgery syndrome.