Epidural injections of indomethacin for postlaminectomy syndrome: a preliminary report

Since there have been side effects reported with the administration of corticosteroids epidurally, their application has been limited. Because some nonsteroidal antiinflammatory drugs have central and spinal antinociceptive actions, we have compared the effects of indomethacin (INM) given by the epidural route to methylprednisolone (MTP). This was a prospective, comparative study in an ambulatory pain care center. Two hundred six patients with recurrent low back pain (Visual Analog Scale >7) and radiculopathy after they had had 2 or more lumbar laminectomies with the diagnosis of "postlaminectomy syndrome" were randomly assigned to 1 of 3 groups. Group I (64 patients) was given 2 epidural injections of lyophilized INM 1 mg. Group II (60 patients) received 2 injections of 2 mg of INM at the same intervals. Group III (82 patients) was treated by 2 epidural injections of MTP 80 mg. In every case, the medication was diluted in 3 mL of 0.5% bupivacaine. Reductions of pain were assessed by changes in the Visual Analog Scale; physical activities, attitude, and medication intake were graded by the Pain Progress Score recorded before each treatment and 2 wk after the last. After each injection, all patients had pain relief to Visual Analog Scale <3. Increased analgesia (P < 0.05) was noted when a double dose of INM was used (Group II) or when 80 mg of MTP was given. The total average scores of the Pain Progress Score showed significant differences at the second injection in Groups II and III only. Physical activity, emotional attitudes, and medication intake were also improved but the changes were not statistically significant. In conclusion, in this group of patients, INM produced adequate analgesia in Groups I and II, with evidence suggesting that 2 mg of INM may produce a similar degree of pain relief as 80 mg of MTP after the second injection. Other nonsteroidal antiinflammatory drugs may be explored in the future for the same purpose.