Comparison of 30-Day Complications Between Navigated and Conventional Single-level Instrumented Posterior Lumbar Fusion

Study Design. Retrospective cohort comparison study. Objective. To compare perioperative outcomes between navigated and conventional single-level instrumented posterior lumbar fusions in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Summary of Background Data. Although multiple studies have investigated the accuracy of pedicle screw placement and radiation exposure with navigation, no study has compared perioperative complications between navigated and conventional posterior lumbar fusion. The potential benefits of navigation include improved accuracy of screw placement and reduced surgeon radiation exposure, but this is balanced by potential operative time and surgical site contamination/infection related to this bulky technology. Methods. Patients who underwent navigated or conventional single-level posterior instrumented lumbar fusions were identified in the 2010-2015 NSQIP database. The usage of navigation was characterized. Patient characteristics and comorbidities were compared between the two treatment groups. Propensity score matching was done and comparisons were made for operative time, hospital length of stay, postoperative complications, and 30-day readmissions between the two cohorts. Results. The percentage of navigated cases tended to increase over years studied to approximately 10%. After propensity matching to control potential confounding factors, statistical analysis revealed no significant difference in operative time and for most adverse events including wound infection, return to the operating room, and readmission. There were significantly lower blood transfusions in the navigated cohort (2.84% vs. 7.15%, P<0.001). Patients who underwent navigated surgery also had a shorter mean hospital length of stay (0.2 day difference, P = 0.016). Conclusion. The reduced blood loss and mildly reduced hospital length of stay identified for the navigated cases are probably markers of more minimally invasive surgery in the navigated cohort. The current study could not identify other differences in operative time, wound infection, or return to the operating room/readmission between navigated and conventional single level posterior instrumented lumbar cases.