A randomized placebo-controlled trial of single-dose IM corticosteroid for radicular low back pain.

STUDY DESIGN: A randomized, double-blind, placebo-controlled trial of patients with radicular low back pain who present to an emergency department (ED) within 1 week of pain onset. OBJECTIVE: We hypothesized that a single intramuscular 160 mg dose of methylprednisolone acetate would improve pain and functional outcomes 1 month after ED discharge if the corticosteroid were administered early in disease symptomotology. SUMMARY OF BACKGROUND DATA: Parenteral corticosteroids are not recommended for acute, radicular low back pain, though their role in this disease process is ill-defined. To date, this medication class has only been studied in a highly selected group of patients requiring hospitalization. METHODS.: Adults between the ages of 21 and 50 who presented to an ED with low back pain and a positive straight leg raise test were enrolled. The primary outcome was change in pain intensity on an 11 point numerical rating scale 1 month after ED visit. Secondary outcomes 1 month after ED discharge included analgesic use, functional disability, and adverse medication effects. RESULTS: Six hundred thirty-seven patients were approached for participation, 133 were eligible, and 82 were randomized. Baseline characteristics were comparable between the groups. The primary outcome, a comparison of the mean improvement in pain intensity, favored methylprednisolone by 1.3 (P = 0.10). Some secondary outcomes favored methylprednisolone, such as use of analgesic medication within the previous 24 hours (22% vs. 43%, 95% CI for difference of 20%: 0%-40%) and functional disability (19% vs. 49%, 95% CI for difference of 29%: 9%-49%). Adverse medication effects 1 week after ED discharge were reported by 32% of methylprednisolone and 24% of placebo patients (95% CI for difference of 9%: -12% to 30%). CONCLUSION: This study was a negative study, though there was a suggestion of benefit of methylprednisolone acetate in a population of young adults with acute radicular low back pain. Further work with a larger sample of patients is needed.

Parenteral corticosteroids for Emergency Department patients with non-radicular low back pain.

Although not recommended for low back pain, the efficacy of systemic corticosteroids has never been evaluated in a general low back pain population. To test the efficacy of systemic corticosteroids for Emergency Department (ED) patients with low back pain, a randomized, double-blind, placebo-controlled trial of long-acting methylprednisolone was conducted with follow-up assessment 1 month after ED discharge. Patients with non-traumatic low back pain were included if their straight leg raise test was negative. The primary outcome was a comparison of the change in a numerical rating scale (NRS) 1 month after discharge. Of 87 subjects randomized, 86 were successfully followed to the 1-month endpoint. The change in NRS between discharge and 1 month differed between the two groups by 0.6 (95% confidence interval -1.0 to 2.2), a clinically and statistically insignificant difference. Disability, medication use, and healthcare resources utilized were comparable in both groups. Corticosteroids do not seem to benefit patients with acute non-radicular low back pain.