A recent study conducted at the Hospital for Special Surgery (HSS) has shown that both robotic-assisted navigation (RAN) and augmented reality (AR) technologies achieve remarkable precision and safety in placing pedicle screws during spinal surgeries. The findings, published online ahead of print in the journal Spine, represent the first head-to-head comparison of these two advanced surgical techniques.
“Compared to traditional freehand methods, robotic-assisted navigation and augmented reality both provide significantly higher accuracy,” said Dr. Darren R. Lebl, a spine surgeon and director of research at HSS, who served as the study’s lead investigator. “This is the first study to directly compare the precision of these technologies for pedicle screw placement.”
Innovations in Spinal Surgery
Precise positioning of pedicle screws is crucial in spinal surgery to stabilize the spine and achieve successful outcomes. Over the past decade, technological advancements like RAN and AR have introduced new levels of precision, safety, and efficiency in surgical procedures.
- Robotic-Assisted Navigation (RAN): This technique combines robotic arm guidance with 3D imaging and GPS-like navigation. Surgeons can pre-plan procedures using advanced software, allowing for minimally invasive surgeries with precise control.
- Augmented Reality (AR): AR overlays 3D images of the patient’s anatomy directly onto the surgeon’s field of vision via a headset. It relies on preoperative CT scans to guide and execute the surgery in real time.
“In addition to improved accuracy, these technologies offer other benefits, such as reduced radiation exposure during surgery and enhanced safety,” Dr. Lebl explained. “They are being adopted by more medical centers across the country.”
Key Findings from the Study
The study included 212 adult patients who underwent lumbar or sacral spine surgery for degenerative conditions between June 2020 and October 2023. A total of 1,211 pedicle screws were placed: 827 using RAN and 384 using AR.
To assess accuracy, researchers used the Gertzbein-Robbins classification system, which grades screw placement as A (fully within the pedicle), B (up to 2 millimeters deviation, still acceptable), C, or D (both deemed unacceptable). Independent spine surgeons evaluated all screws post-surgery using CT scans or 3D fluoroscopy.
The findings revealed:
- Robotic-Assisted Navigation (RAN): 99.6% of screws were graded A or B, with a higher proportion achieving the top Grade A rating.
- Augmented Reality (AR): 98.7% of screws were graded A or B.
- Overall Accuracy: Across both groups, 92.6% of screws achieved the top Grade A rating.
“These results highlight the exceptional accuracy of both techniques, proving them to be safe and reliable for pedicle screw placement,” Dr. Lebl said. “The slightly higher rate of Grade A screws in the RAN group suggests that robotic systems may offer an edge in precision.”
Shaping the Future of Spine Surgery
Dr. Lebl believes this research points to a transformative future for spine surgery. “Our team at HSS is committed to advancing spinal procedures to make them safer, less invasive, and more precise,” he noted. “We’ve already integrated real-time confirmation of implant positioning during surgery, ensuring everything is accurate before the patient leaves the operating room.”
As these technologies continue to evolve, Dr. Lebl anticipates greater automation in the surgical process. “The focus will shift towards deciding the timing and type of surgery, while execution becomes increasingly streamlined and automated,” he said.
With innovations like RAN and AR, spine surgery is entering a new era, where precision and patient safety take center stage, redefining what’s possible in modern medical care.
About HSS
HSS is the world’s leading academic medical center focused on musculoskeletal health. At its core is Hospital for Special Surgery, nationally ranked No. 1 in orthopedics (for the 15th consecutive year), No. 3 in rheumatology by U.S. News & World Report (2024-2025), and the best pediatric orthopedic hospital in NY, NJ and CT by U.S. News & World Report “Best Children’s Hospitals” list (2024-2025). In a survey of medical professionals in more than 20 countries by Newsweek, HSS is ranked world #1 in orthopedics for a fifth consecutive year (2025). Founded in 1863, the Hospital has the lowest readmission rates in the nation for orthopedics, and among the lowest infection and complication rates. HSS was the first in New York State to receive Magnet Recognition for Excellence in Nursing Service from the American Nurses Credentialing Center five consecutive times. An affiliate of Weill Cornell Medical College, HSS has a main campus in New York City and facilities in New Jersey, Connecticut and in the Long Island and Westchester County regions of New York State, as well as in Florida. In addition to patient care, HSS leads the field in research, innovation and education. The HSS Research Institute comprises 20 laboratories and 300 staff members focused on leading the advancement of musculoskeletal health through prevention of degeneration, tissue repair and tissue regeneration. In addition, more than 200 HSS clinical investigators are working to improve patient outcomes through better ways to prevent, diagnose, and treat orthopedic, rheumatic and musculoskeletal diseases. The HSS Innovation Institute works to realize the potential of new drugs, therapeutics and devices. The HSS Education Institute is a trusted leader in advancing musculoskeletal knowledge and research for physicians, nurses, allied health professionals, academic trainees, and consumers in more than 165 countries. The institution is collaborating with medical centers and other organizations to advance the quality and value of musculoskeletal care and to make world-class HSS care more widely accessible nationally and internationally. www.hss.edu.