1522. Complication Risk in Primary and Revision Minimally Invasive Lumbar Interbody Fusion: A Comparable Alternative to Conventional Open Techniques?

Authors: Peter Gust Passias; Cole Bortz, BA; Frank Segreto, BS; Samantha Horn, BA; Dennis Vasquez-Montes, MS; Mohamed Moawad, MPH; Virginie Lafage, PhD; Renaud Lafage, MS; Charla Fischer, MD; Themistocles Protopsaltis, MD; Muhammad Burhan Janjua, MD (Brooklyn Heights, NY)

Introduction: As an increasing number of MIS lumbar fusions are performed, it is important to assess the corresponding complication risks between primary and revision lumbar interbody fusion procedures. Methods: Patients > 18yr undergoing primary and revision lumbar interbody fusion were propensity score matched for comorbidities, levels fused. Cases were grouped: MIS, open. Patient factors, surgical factors, and periop complication rates were compared between primary and revision cases using means comparison tests. Results: Included: 154 lumbar interbody fusion patients(62±12yr, 62%F, 29±6 kg/m 2 ). 44(29%) MIS, 110(71%) open. Revisions within MIS and open were 40.9% and 53.6%, respectively. Within both MIS and open groups there were no differences between primary and revision cases in: age, sex, BMI, CCI, levels fused, surgical approach, rates of laminectomy, number of interbodies, EBL, op time, LOS, or ICU LOS, rates of postop complications (cardiac, pulmonary, urinary, infection, and anemia complications)(all p>0.05). Primary MIS cases had higher rates of intraoperative complications as compared to revision cases(19% vs 0.0%,p=0.048), unlike open procedures, primary cases had lower intraoperative complication rates(0% vs 7%,p=0.058). MIS and open groups did not differ in operative time of primary surgery(279 min vs 280,p=0.976), MIS revision procedures were shorter (244 vs 296min,p=0.024). For both primary and revision procedures, there were no differences between MIS and open groups in overall rates of postoperative complications(all p>0.05); however, primary MIS cases had higher intraoperative complication rates than primary open cases(19% vs 0%,p=0.001). Conclusion: Clinical outcomes of revision MIS lumbar interbody fusion were similar to those of primary surgery, with no differences in op-time, LOS, EBL, or postop complication rates. Despite higher intraop complication rates for primary MIS fusions, postop clinical outcomes were similar between MIS and open groups for both primary and revision surgery. These results suggest MIS lumbar interbody fusion may be a comparable alternative to conventional open revision.