Study Design. A randomized controlled trial.
Objectives. To assess the effectiveness of decompressive surgery as compared with nonoperative measures in the treatment of patients with lumbar spinal stenosis.
Summary of Background Data. No previous randomized trial has assessed the effectiveness of surgery in comparison with conservative treatment for spinal stenosis.
Methods. Four university hospitals agreed on the classification of the disease, inclusion and exclusion criteria, radiographic routines, surgical principles, nonoperative treatment options, and follow-up protocols. A total of 94 patients were randomized into a surgical or nonoperative treatment group: 50 and 44 patients, respectively. Surgery comprised undercutting laminectomy of the stenotic segments in 10 patients augmented with transpedicular fusion. The primary outcome was based on assessment of functional disability using the Oswestry Disability Index (scale, 0–100). Data on the intensity of leg and back pain (scales, 0–10), as well as self-reported and measured walking ability were compiled at randomization and at follow-up examinations at 6, 12, and 24 months.
Results. Both treatment groups showed improvement during follow-up. At 1 year, the mean difference in favor of surgery was 11.3 in disability (95% confidence interval [CI], 4.3–18.4), 1.7 in leg pain (95% CI, 0.4–3.0), and 2.3(95% CI, 1.1–3.6) in back pain. At the 2-year follow-up, the mean differences were slightly less: 7.8 in disability (95% CI, 0.8–14.9) 1.5 in leg pain (95% CI, 0.3–2.8), and 2.1 in back pain (95% CI, 1.0–3.3). Walking ability, either reported or measured, did not differ between the two treatment groups.
Conclusions. Although patients improved over the 2-year follow-up regardless of initial treatment, those undergoing decompressive surgery reported greater improvement regarding leg pain, back pain, and overall disability. The relative benefit of initial surgical treatment diminished over time, but outcomes of surgery remained favorable at 2 years. Longer follow-up is needed to determine if these differences persist.