Is augmented reality ready for prime time as a surgical modality in orthopedic surgery?
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AR guidance is happening now
AR guidance is certainly ready for prime time in surgery, and, in fact, the technology is used every day in the United States.
The newest iterations of AR guidance improve upon traditional navigation and robotics by using cameras on a head-mounted device for tracking, obviating the need for separate tracking cameras. These systems can empower surgeons by projecting 3D, patient-specific anatomy, instruments and implants directly into the patient from the surgeon’s point of view in real-time. This technology greatly enhances the surgeon’s sense of sight without compromising the sense of touch, resulting in improvement in human capability. These patient-specific 3D AR guidance technologies are distinctly different from AR technologies that provide dashboard-style information in the surgeon’s visual field instead of on an adjacent flat screen.
When did AR 3D guidance become ready for prime time? Recent advances in headset technology have allowed for the development of extremely accurate spatial tracking. Bio skills studies using these AR headsets for placement of acetabular screws demonstrate that AR guidance leads to equal or greater accuracy than current robotic systems. New surgical planning and AR lens applications based on this novel technology can leverage the capabilities of the headsets to provide surgical-grade function, resulting in FDA clearance for patient-specific AR guidance systems in spine and hip surgery. Personal experience with more than 300 AR-guided hip arthroplasties has shown seamless, efficient, enjoyable workflow that doesn’t add to total surgical time.
We have often seen examples of humans being replaced by more capable machines. Perhaps for the first time, we now see examples of machines being replaced by more capable humans. AR guidance isn’t just the future of orthopedic surgery — it’s happening now.
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Stephen B. Murphy, MD, is an associate professor in orthopedic surgery at Tufts University Medical School in Boston.
AR technology ‘quickly evolving’
Augmented reality is gaining considerable traction in spine surgery. The AR system that is commercially available allows for pedicle screw placement in the spine. It provides a heads-up retina display with 3D imaging of the spine (with skin intact), as well as conventional 2D navigation images. The headset has a built-in surgical tracking system, which eliminates any line of site issues or the need to look away from the surgical field associated with traditional 2D navigation systems. At Rush, we performed cadaveric validation of the system for percutaneous placement of thoracolumbar pedicle screws and reported accuracy rates of 100% and 98.2% in the lumbosacral and thoracic spine, respectively, with less than 2-mm deviation of the screw tip from the planned trajectories.
I have used this system in my practice for more than 1 year since initial commercialization. The system has been particularly helpful in placing minimally invasive (percutaneous) pedicle screws, greatly enhancing surgical efficiency with significantly reduced surgical times while allowing for precise screw placement. The efficiencies provided by the system are particularly advantageous in open multilevel thoracolumbar deformity surgical constructs. The technology and its applications are quickly evolving. I anticipate in the near future using AR to guide bony decompression, interbody fusion and spinal osteotomies.
- Molina CA, et al. J Neurosurg Spine. 2020;doi:10.3171/2020.6.SPINE20370.
Frank M. Phillips, MD, is the Ronald DeWald Endowed Professor of Spinal Deformities and director of the division of spine surgery at Rush University Medical Center.
Growing AR interest, utilization
Augmented reality is indeed ready for prime time. During the past 2 decades, AR has emerged as a useful tool in orthopedic surgery utilizing a fusion of real-time imaging via a computer-generated 2D or 3D projection in an actual surgical environment. Between 2001 and 2015, there were 378 PubMed searchable articles on AR in surgery compared with 1,014 articles between 2016 and 2021, demonstrating remarkable growth in interest and utilization.
AR is likely to become more prevalent in orthopedic surgery as computer and imaging use continues to increase. In resident education, a virtual interactive presence rather than an attending physician being present in the room was shown to be safe with an improved educational experience and similar operating times in shoulder arthroscopy, as well as shoulder arthroplasty.
In certain circumstances, AR may improve both accuracy and safety for experienced surgeons. Fracture fixation with the use of AR via a camera-augmented mobile C-arm device reduced radiation exposure by 46% on average without increasing operative times. Similar technology is now being investigated in preclinical studies to determine accurate intraoperative mechanical alignment, which can be used in both total knee arthroplasty and osteotomy surgery. The possible utilities are exciting and far reaching
AR is an expanding tool that allows orthopedic surgeons to better understand, visualize, learn and treat difficult problems. It is prime time and only going to grow within orthopedics in the future.
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David E. Hartigan, MD, is an assistant professor and Daniel J. Liechti, MD, is a sports medicine fellow at Twin Cities Orthopedics in Minnesota.