P109. Improvements in screw placement and accuracy with newer generation robotic-assisted minimally invasive instrumented lumbar fusions

BACKGROUND CONTEXT Lumbar fusion techniques continue to evolve to improve patient safety, minimize soft tissue dissection, and increase the reliability and accuracy of pedicle screw placement. Early technical advancements included navigation and robotic assistance with minimally invasive approaches. Current generation robots now have a more robust and stable surgical arm and the ability to scan the entire surgical field to improve reliability and accuracy of pedicle screw placement. PURPOSE The purpose of this study is to determine if improvements from the earlier generation of surgical robots improve reliability and accuracy of pedicle screw placement. STUDY DESIGN/SETTING Comparative observational cohort. PATIENT SAMPLE A consecutive series of patients undergoing minimally invasive instrumented posterolateral fusion by a single surgeon using second generation (2ndGen) versus third generation (3rdGen) robotic guidance. OUTCOME MEASURES Number of screws planned, number of screws executed or abandoned, number of screws placed accurately. METHODS A consecutive series of patients undergoing minimally invasive instrumented posterolateral fusion by a single surgeon using second generation (2ndGen) versus third generation (3rdGen) robotic guidance were identified. Compared to the 2ndGen robot, the 3rdGen robot has a more robust robotic arm and scans the entire surgical field. The planning software remains the same. Data collected included demographics, total fluoroscopy time, number of planned screws, number of executed screws and number of screws executed accurately. Accurate screw placement was defined as screw placement in the planned position and trajectory without a need for repositioning and confirmed with intraoperative fluoroscopy and radiographs. RESULTS There were 70 cases in each group. The groups were comparable in terms of sex distribution, gender and body mass index.  Even though there were more single-level cases in the 2ndGen (43, 61%) compared to the 3rdGen group (27, 39%, p=0.009); the mean total fluoroscopy time (58s vs 63s, p=0.739) and mean fluoroscopy time per level (46s vs 40s, p=0.399) were similar between the two groups. There was a statistically significantly higher rate of abandoned screw placements in the 2ndGen group compared to the 3rdGen group (p CONCLUSIONS Newer generation surgical robotic assistance, with a more robust and stable surgical arm and of the ability to scan the entire surgical field led to a lower rate of abandoned screw placements and greater screw accuracy compared to second generation robots. Further studies are needed to determine if these improvements in screw placement and accuracy translate to improved clinical outcomes. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.