D45. Early Outcomes of Muscle Flap Closures in Complex Spine Surgeries: A Propensity-matched Cohort Analysis

Abstract

PURPOSE: Plastic surgery closure with muscle flaps after complex spinal reconstruction has become popular. Existing evidence for this practice consists of small, uncontrolled, single-center cohort studies. We aimed to compare 30-day postoperative wound-related complications between flap closure and traditional closure after posterior thoracolumbar fusions (PTLFs) for non-infectious pathologies using a national database. METHOD: We performed a propensity-matched analysis using the 2010-2020 NSQIP dataset. RESULTS: Of 117,756 PTLFs meeting inclusion criteria, a higher proportion of flap closures had ASA Class III/IV than traditional closures (65.4% vs. 54.1%; p<0.001). 1,520 PTLFs (760 in each group) were included in the propensity-matched cohort. Unadjusted 30-day wound complication rates were 3.0% for flap and 1.6% for traditional closure (p=0.09). Surgeries were longer with flap closure (p<0.001). After adjusting for operative time, flap closure was associated with lower wound complication odds (AOR, 0.98; p=0.041) and prolonged LOS (AOR, 1.05; p=0.001). Readmission, reoperation, home discharge, mortality, and non-wound complication were not associated with flap use. CONCLUSION: Plastic surgery closure was performed in patients with higher ASA classifications, suggesting consultation in sicker patients. Our propensity-matched cohort analysis of flap closure in PTLFs resulted in lower odds of wound complications than traditional closure. Sequelae of longer procedure time in flap closure may contribute to longer LOS. Further study is needed to assess long-term complications in prophylactic flap closure in complex spine surgeries.