Comparison of Patients Operated for Lumbar Spinal Stenosis with and without Spondylolisthesis – A Secondary Analysis of the NORDSTEN Trials

Study Design. Observational cohort study (secondary analysis of two randomized trials). Objective. The aim of this study was to investigate whether function, disability, pain, and quality of life before surgery and patient-reported outcome as well as complication and reoperation rates up to 2 years after surgery differ between lumbar spinal stenosis patients with and without spondylolisthesis. Summary of Background Data. Lumbar spinal stenosis is a degenerative condition of the spine, which appears with or without degenerative spondylolisthesis often presenting similar signs and symptoms. Materials and Methods. This study is a secondary analysis of two randomized trials on patients with lumbar spinal stenosis with and without spondylolisthesis conducted at 16 public Norwegian hospitals. Disability, function, back pain, leg pain, quality of life, complication, and reoperation rates up to 2 years after surgery were compared between the two cohorts. Results. A total of 704 patients were included in this study, 267 patients with spondylolisthesis [median age: 67.0 yr (IQR: 61.0–72.0 yr); 68.7% female] and 437 patients without spondylolisthesis [median age: 68.0 yr (IQR: 62.0–73.0 yr); 52.9% female]. In the linear mixed-model analysis there were no significant differences in disability, function, back pain, leg pain, and quality of life scores between the two cohorts of patient with and without spondylolisthesis before surgery or at 2 years of follow-up. The complication rate was 22.9% in patients with spondylolisthesis and 12.1% in patients without spondylolisthesis ( P <0.001). There were no significant differences in reoperation rates. Conclusions. In patients with lumbar spinal stenosis the symptom burden before surgery and the clinical outcome up to 2 years after surgery were similar independently of a concomitant spondylolisthesis. Level of Evidence. II.