Surgical and nonsurgical management of lumbar spinal stenosis: four-year outcomes from the maine lumbar spine study.

STUDY DESIGN: A prospective cohort study of patients with lumbar spinal stenosis recruited from the practices of orthopedic surgeons and neurosurgeons throughout Maine.

OBJECTIVE: To assess 4-year outcomes for patients with lumbar spinal stenosis treated surgically or nonsurgically.

SUMMARY OF BACKGROUND DATA: Surgery for lumbar spinal stenosis has increased dramatically despite the lack of randomized trials comparing surgical with nonsurgical treatments. Long-term evaluation of surgical series has documented deterioration in initial symptomatic improvement, but few studies have compared long-term outcomes of surgical and nonsurgical treatment.

METHODS: Eligible, consenting patients had baseline interviews with mailed follow-up questionnaires at 3, 6, and 12 months, then annually thereafter. Clinical data were obtained at baseline from a physician questionnaire. Outcomes included patient-reported symptoms of leg and back pain, functional status, and satisfaction.

RESULTS: Of 148 patients with lumbar spinal stenosis initially enrolled, 4-year outcomes were available on 119 patients (80.4%): 67 of 81 (83%) treated surgically and 52 of 67 (78%) treated nonsurgically. The surgically treated patients had more severe symptoms and worse functional status at baseline and better outcomes at 4-year evaluation than the nonsurgically treated patients. After 4 years, 70% of the surgically treated and 52% of the nonsurgically treated patients reported that their predominant symptom, either leg or back pain, was better (P = 0.05). Satisfaction of patients with their current state at 4 years was reported by 63% of the surgically treated and 42% of the nonsurgically treated patients (P = 0.04). Surgical treatment remained a significant determinant of 4-year satisfaction, even after adjustment for other independent predictors (P = 0.001). For the nonsurgically treated patients, there was no significant change in outcomes over 4 years, whereas the initial improvement seen in the surgically treated patients modestly decreased over the subsequent 4 years.

CONCLUSIONS: For the patients with severe lumbar spinal stenosis, surgical treatment was associated with greater improvement in patient-reported outcomes than nonsurgical treatment at 4-year evaluation, even after adjustment for differences in baseline characteristics among treatment groups. The relative benefit of surgery declined over time but remained superior to nonsurgical treatment. Outcomes for the nonsurgically treated patients improved modestly and remained stable over 4 years. Determining whether outcomes continue to converge will require longer-term evaluation.