Objective
Several kinds of steroids had been used epidurally for the treatment of low back pain, but there were few available medical reports as to the effects of each steroid. The purposes of this study were to evaluate the effects of epidural steroid injections and to investigate the factors affecting the results.

Method
Forty four backache patients were randomly assigned to one of three groups: Group 1, epidural saline as a control group(n=12); Group 2, epidural triamcinolone and 1% lidocaine(n=13); Group 3, epidural dexamethasone and 1% lidocaine(n=19). The effects of epidural injections were measured by pain self-assessment scale(pain score) and Rubin scale(success rate).

Results
The pain scores of steroid groups after one to seven days after the injections were significantly lower than those of the control group(p＜0.05), but there were no statistical differences(p＞0.05) between two steroid groups. The overall success rate of the steroid groups was 68.8%. Although there were no statistically significant differences between the steroid groups with respect to sex, age and duration, the younger age group seemed to respond better to the treatment.

Conclusion
We founded that epidural steroid injection could be a valuable adjunct to the management of low back pain but its effective duration was relatively short. Physicians should keep in mind that comprehensive treatment including rest, medication, physical therapy, exercise and education ought to be provided for the better clinical results.