Results of a randomized, double-blind study, "Epidural Corticosteroid Injections for Sciatica Due to Herniated Nucleus Pulposus," were recently published in the New England Journal of Medicine.1 The study's working premise was that while epidural corticosteroid injections are commonly used for sciatica, their efficacy has not been established. The trail tested the effects of epidural injections of a corticosteroid (methylprednisolone acetate), and isotonic saline (placebo group.).
The authors compared the epidural steroid and placebo groups at three weeks, six weeks and three months:
Three weeks after treatment, the two groups showed no statistical difference in their visual-analogue scores for leg pain; McGill Pain Questionnaire; the Sickness Impact Profile scores; the number of days of limited activity; and the physical examination measures. The only significant difference between the two groups was that the methylprednisolone group "had greater improvement in the finger-to-floor distance (P=0.006), and a smaller proportion of patients in this group had sensory deficits (P=0.03)." At six weeks, the results were similar. The only difference "was in the degree of improvement in leg pain, as assessed by the visual-analogue pain scale, which was greater in the methylprednisolone group (difference in mean change, -11.0; 95 percent confidence interval, -21.1 to - 0.9; P=0.03)."
But by the three month mark, "the two groups did not differ statistically in any of the outcome measures."
The authors of the study concluded:
"Although epidural injections of methylprednisolone may afford short-term improvement in leg pain and sensory deficits in patients with sciatica due to a herniated nucleus pulposus, this treatment offers no significant functional benefit, nor does it reduce the need for surgery."
Patients with serious sciatica problems should be informed that epidural injections hold no real benefit beyond possible short-term pain relief that could be accomplished by much safer means. In contrast, according to the literature,2 the side effects include headache, accidental puncture of the dura, aseptic meningitis, infection and neurologic problems.
References
- Carette S, LeClaire R, Marcoux S, et al. Epidural corticosteroid injections for sciatica due to herniated nucleus pulposus. N Engl J Med 1997;336:1634-40.
- Mandell P, Lipton MH, Bernstein J, et al. Low back pain. An Historical and Contemporary Overview of the Occupational, Medical, and Psychological Issues of Chronic Pain. Thorofare, New Jersey: SLACK,Inc.;1989. 219p.
