269. Clinically relevant improvement is maintained 5 years after surgery for spinal stenosis

Abstract

BACKGROUND CONTEXT Lumbar spinal stenosis (LSS) is a common condition in the elderly population and is associated with significant morbidity and decreased quality of life. Many patients manage with little to no treatment, but for the patients in whom lower extremity pain and disability are unacceptable, surgical intervention is shown to provide good relief of symptoms and pain. There is little evidence on how many patients obtain a clinically relevant improvement in function and whether this effect is sustained 5 years after surgery. PURPOSE The aim of this study was to evaluate the proportion of patients who achieve and maintain a clinically relevant improvement at 1, 2 and 5 years postoperatively. STUDY DESIGN/SETTING The study was performed as a retrospective cohort study on patients who underwent surgery at the Spine Centre of Southern Denmark, Middelfart; The Regional Hospital of Silkeborg and University Hospital of Zealand in Koge. PATIENT SAMPLE A total of 6,063 patients who underwent decompression due to spinal stenosis at three spine centers in Denmark were included in our study. We had follow-up data available on our main outcome measure (ODI) on 75% at 1-year, 70% at 2-year, and 62% at 5-year follow-up. OUTCOME MEASURES Oswestry Disability Index (ODI), EuroQoL-5D-3L (EQ-5D), visual analogue scale leg pain (VAS-leg) and visual analogue scale back pain (VAS-back). METHODS We included patients who underwent first-time decompression due to LSS at three tertiary Spine Centers in Denmark. Data was collected prospectively in the National Spine Registry of Denmark (DaneSpine). Based on the outcome measures, the patients who obtained a minimal clinically relevant difference in outcome (MCID) were identified at 1-, 2- and 5-years post-surgery. RESULTS The mean change from baseline to 5-years post-surgery was 0.2 on EQ-5D; -18.9 on ODI, -18.9 on VAS back and 29.8 on VAS. We found that 86% of patients obtained the MCID on at least one parameter, with 68.9% obtaining MCID on two or more outcome measures. VAS back was found with a statistically important difference in the percentage of patients who achieved MCID at 1- and 5-years postsurgery. For the remaining outcome measures no statistically important difference was found. CONCLUSIONS Decompression as treatment for LSS is a safe and reliable option with low complication rates. Most patients achieve a clinically relevant difference in outcome on one or more parameters, which is maintained 5 years after surgery. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.