277 Clinical Outcome With and Without Adherence to Evidence-based Medicine Guidelines for Lumbar Degenerative Spondylolisthesis Fusion Patients

INTRODUCTION: Degenerative lumbar spondylolisthesis (DS) patients are treated with instrumented fusion, following EBM guidelines, and typically have excellent clinical outcomes. However, not all lumbar fusion procedures adhere to EBM guidelines, typically due to a lack of prospective data. METHODS: This study compared outcomes of lumbar fusion procedures for degenerative spondylolisthesis in two groups: 125 patients treated according to EBM guidelines and 21 patients without EBM literature support. ODI scores were collected pre- and post-surgery and categorized into SCB, MCID, no MCID, or no change/worsening. Statistical analysis included χ2, Fisher exact, and t-student tests. Multivariate logistic regression analyzed the odds of achieving MCID after six months of follow-up. RESULTS: The study included a total of 146 lumbar fusion patients, with the majority (125/146) adhering to EBM guidelines (EBM concordant) while a smaller proportion (21/146) did not (EBM discordant). The EBM concordant group demonstrated a statistically significant improvement in ODI scores compared to the EBM discordant group (p = 0.02). Compliance with EBM guidelines was associated with higher odds of achieving MCID, with an odds ratio of 2.93 and a confidence interval of 1.128-7.58 (p = 0.027). In the EBM concordant group, 42% of patients achieved SCB, and 64.8% showed MCID, whereas in the EBM discordant group, only 14% achieved SCB, and 38.1% showed MCID. These findings suggest that adherence to EBM guidelines in lumbar fusion procedures may lead to better clinical outcomes for patients. CONCLUSIONS: Patients whose lumbar fusions met the EBM criteria exhibited better self-reported outcomes at six months compared to those who did not meet the requirements. In order to strengthen EBM-guided patient care, an expanded knowledge base is needed.