Illustration of average Oswestry Disability Index scores for function at different follow-up points by type of epidural. ^*P value at different time intervals as compared with baseline (within group, pair-wise comparisons with Bonferroni correction) #1 P = 0.052, #2 P = 0.652, #3 P = 0.951, #4 P = 0.896, #5 P = 0.963, #6 P = 0.925 respectively, for between-group comparisons at specified time intervals with Bonferroni correction.