Learning Curves for Robot-Assisted Pedicle Screw Placement: Cumulative Sum Analysis

Introduction: Robot-assisted surgery has demonstrated benefits in improving pedicle screw accuracy and reducing complications. Hesitancy to adopt robotic platforms may come from beliefs that robots are costly, increase surgery duration, and may be difficult to learn to use. We report the initial operative time learning curves of four surgeons.

Methods: A retrospective chart review of patients undergoing pedicle screw placement with the ExcelsiusGPS robotic platform for degenerative pathologies between July 2019 and November 2023 was conducted. Surgeries were performed by four surgeons at a single institution. Operative times for the first 30 cases of each surgeon were evaluated with linear regression and cumulative sum analyses.

Results: The surgeons in this study included two senior neurosurgery attendings, one senior orthopedic attending, and one junior neurosurgery attending in their first year of practice. A total of 120 patients were included in this study. The cohort was 70.8% White and 39.2% were female. The average age was 61.712.7 years. The average operative time for each surgeon ranged from 185.1 to 213 minutes. Linear regression analysis demonstrated that surgeons reduced operative time by 1.1-3.4 minutes per case, translating to a decrease in 33-102 minutes by the end of the 30 cases. On cumulative sum analysis, proficiency was reached at 21, 16, 14, and 12 cases for the four surgeons. The junior surgeon had the shortest average operative time and the earliest proficiency. No cases required intraoperative screw revision. The average hospital length of stay was 3.12.2 days, and the 30-day reoperation rate was 3%.

Conclusion : This study demonstrates a consistent learning curve for robot-assisted pedicle screw placement across four surgeons of different levels of experience and specialties. For all four surgeons, significant reductions in operative time were observed without complications in the first 30 cases. Our findings suggest that once a robotic platform is acquired, multiple surgeons at a single institution can rapidly learn to use the technology, potentially improving its cost effectiveness.