P95. Geographic variation in the philosophy of adult spinal deformity management and patient outcomes: A propensity score matching analysis from the Prospective Evaluation Deformity Surgery (PEEDS) Study

BACKGROUND CONTEXT Severity of deformity, preoperative disability, and surgical strategies are variable between, and within, centers performing reconstructive surgery for spinal deformity. However, geographic variation in how surgeons manage ASD patients worldwide is unknown. PURPOSE The purpose of this study was to compare the surgical approach and clinical outcomes of elderly patients treated with fusion for spinal deformity in North America and Asia. STUDY DESIGN/SETTING Retrospective review of the prospectively collected data. PATIENT SAMPLE All patients enrolled in the database were eligible and were propensity score matched according to their region (North America and Asia) OUTCOME MEASURES Surgical details, postoperative radiological parameter and health-related quality of life (HRQoL) scores at preoperative and 2 years, and occurrence of adverse events within the study period were compared in the matched pairs with dependent statistical tests. METHODS The two largest regions (North America and Asia) from the Prospective Evaluation Deformity Surgery (PEEDS) database, consisting of ASD patients over aged 60 with primary spinal fusion of at least 5 segments with a minimum of 2 year follow-up, were compared. Patients were 1:1 propensity score-matched using age, gender, Charlson Comorbidity Index, lumbar lordosis (LL), pelvic incidence (PI)-LL mismatch, sagittal vertical axis (SVA), absolute lumbar cobb angle, and sacral slope for calculation of propensity score and applying greedy algorithm to identify the best matches between the 2 regions with maximal absolute distance of 0.25 in propensity score to each other. RESULTS Out of the 219 patients enrolled in the database, 82 propensity score-matched patients were identified (n=41 in each region), with a median age of 68.0 (range 64-72) years (NA) and 68.0 (range 63-73) years (A). Both cohorts had comparable distributions of all preoperative radiological parameters and HRQoL scores. Out of the 219 patients enrolled in the database, 82 propensity score-matched patients were identified (n=41 in each region), with a median age of 68.0 (range 64-72) years (NA) and 68.0 (range 63-73) years (A). Both cohorts had comparable distributions of all preoperative radiological parameters and HRQoL scores. Patients treated in NA had higher proportion of single stage surgery (88% vs 44%, p CONCLUSIONS In this propensity score matched analysis, we demonstrated marked geographic variation in surgical practice toward surgeries for adult spinal deformity despite similar baseline patient characteristics and radiological parameters between North America and Asia. However, the 2 year radiological and clinical outcomes were similar. Further study is necessary to understand the drivers of this variation. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.