LAUSR

STUDY DESIGN Prospective, multicenter cohort study. OBJECTIVE The aim of our study was to assess the course of patients over a period of 3 years undergoing surgical or nonsurgical treatments for degenerative lumbar spinal stenoses (DLSS) based on data from the Lumbar Stenosis Outcome Study (LSOS), prospectively performed in eight hospitals. SUMMARY OF BACKGROUND DATA The optimal treatment strategy for patients with DLSS is still debated. METHODS The outcomes of patients with verified DLSS were quantified by Spinal Stenosis Measure (SSM) symptoms- and SSM function-scores, and EQ-5D-3L (quality of life) summary index (SI) over time (up to 36-month follow-up), and minimal clinically important difference (MCID) in SSM symptoms, SSM function, and EQ-5D-3L SI from baseline to 36-month follow-up. RESULTS For this study, 601 patients met the inclusion criteria; 430 underwent surgery, 18 of them only after more than a year after enrolment, 171 received nonsurgical treatment only. At baseline, patients in the surgical and nonsurgical groups had similar values for the SSM symptoms and SSM function scores, but patients in the surgical group suffered significantly more from buttocks pain and reported more worsening symptoms over the last 3 months before enrollment in the study. Surgically treated patients (except changers) performed significantly better in all clinical outcome measures (P < 0.001) with a plateau at 12-month follow-up staying constant until the follow-up ended. Further, two-thirds of patients in the surgical group had a relevant improvement in function, symptoms, and quality of life, compared with only about half of those in terms of symptoms and even less in terms of function and quality of life with nonsurgical treatment. CONCLUSIONS Surgical treatment of DLSS results in more favorable clinical outcomes with a sustained effect over time, compared to nonsurgical treatment. LEVEL OF EVIDENCE 3.