Study Design: Retrospective study
Background: The fundamental goals of any surgery are to obtain the best outcomes while minimizing risks. In lumbar spine fusion, technological advancements, such as intraoperative three-dimensional (3D) fluoroscopy and navigation/robot use, have sought to improve surgical accuracy and decrease soft tissue trauma all while both directly and indirectly decreasing surgical risks. Surgical site infections (SSIs) are one such complication that can be a major cause of morbidity after lumbar fusions. The objective of this study was to evaluate if the use of these tools is associated with an increase in surgical site infections in patients undergoing instrumented posterior lumbar spine fusions.
Methods: A retrospective review of all adult (>18 years old) patients who underwent open or minimally invasive (MIS) instrumented posterior lumbar spine fusion at a single institution from January 2018 – March 2020 was conducted. Use of 3D fluoroscopy, open versus MIS, navigation/robot versus freehand pedicle screw placement, and infections within 2 years post-operatively were recorded. Additional collected data included demographics, including age, sex, body mass index (BMI), ASA, diagnosis, and operative data, including procedure, operative time, estimated blood loss (EBL), length of stay (LOS), and complications. Patients who underwent in situ fusions without p edicle screw placement were excluded from this study.
Fisher exact test was used to determine the association between 3D fluoroscopy use and incidence of infection in both open and MIS cases. Demographic data, ASA, operative time, EBL, and LOS were compared between 3D fluoroscopy and 2D fluoroscopy cohorts using Student’s t test. Multivariate logistic regression analysis was performed to evaluate the relationship between usage of 3D fluoroscopy and occurrence of infection while controlling for confounding parameters, including EBL, operative time, revision surgery, and use of navigation/robot.
Results: 582 total open cases and 267 MIS cases were included, of which 14.6% and 45% used 3D fluoroscopy, respectively. 49.1% of the open cases were women while 45% of the MIS cases were women.