Surgeons’ Perceptions of Spinal Navigation: Analysis of Key Factors Affecting the Lack of Adoption of Spinal Navigation Technology

DISCUSSION

Confirming the common, but previously undocumented, perception that spinal navigation is not commonly used by spine surgeons, our survey found that most spine surgeons have only superficial experience in spinal navigation, and more than 75% of surgeons rarely used spinal navigation in their surgeries. The most frequently used system is virtual fluoroscopy using C-arm only. Thus, despite ongoing improvements in technology and recent increases in the use of fluoroscopy and MIS, spinal navigation remains infrequently used in everyday practice.

The most commonly cited reasons that spinal navigation is poorly utilized were increased operative time, cost, lack of necessity, unreliable accuracy, and intraoperative glitches. Interestingly, the most frequently selected weakness, longer operative times, may be a misconception, based on recent studies. Sasso and Garrido⁹ showed that spinal navigation using FluoroNav technology, at worst, did not affect operative time and, at best, decreased total case time by an average of 40 minutes. In the setting of preoperative CT merged with open anatomy fiducial registration, Papadopoulos et al.¹⁰ demonstrated that single multi-level registration at the beginning of the procedure could save time with no sacrifice of accuracy in contrast to repetitive single-level registration, thus minimizing increases in operative time. Therefore, future studies should focus on bridging the gap between the evidence of existing studies and surgeons’ perceptions of longer operative time with spinal navigation.

The perceptions regarding spinal navigation accuracy are complex. In our survey, we found that unreliable accuracy was the fourth most commonly selected weakness and increased accuracy was the second most frequently selected advantage of spinal navigation, indicating that surgeons are conflicted as to whether they trust the accuracy of navigation. This ambiguity is somewhat reflected in the literature, although most studies demonstrate improved accuracy of spinal navigation as compared to conventional techniques.^1–4 However, at least one study demonstrated spinal navigation inaccuracy in the setting of thoracic pedicle screw insertion using FluoroNav with a single reference point.¹¹ Accuracy remains a significant concern as our survey showed that more surgeons with greater spinal navigation experience selected unreliable accuracy as a weakness, suggesting that concerns with accuracy are not alleviated with increased navigation experience.

Although issues related to training, technical difficulty, and learning curve are commonly presumed to be major barriers to the acceptance of spinal navigation, we found surgeons did not select them as major weaknesses in the survey. While such issues are likely to exist, especially among surgeons with less spinal navigation experience, it appears that surgeons consider other disadvantages to be more pressing. These findings differ from the results of an earlier survey¹² assessing surgeons’ perceptions of minimally invasive surgery. In the previous survey regarding minimally invasive spine surgery, surgeons selected the difficult learning curve and issues related to training and technical difficulty as major obstacles to the adoption of minimally invasive surgery. These types of issues are easily addressed with improved training protocols and programs. However, our survey results indicate that barriers to adoption of spinal navigation are not due to a difficult learning curve nor to a lack of training opportunities. The barriers to adoption of navigation are more intrinsic to the technology itself, including intraoperative glitches, unreliable accuracy, frustrations with fiducial registration, and line-of-sight issues. These findings suggest that significant improvements in the technology will be required to improve the adoption rate of spinal navigation.

Regarding the advantages of spinal navigation, surgeons indicated they were likely to use spinal navigation because it decreases radiation exposure, increases accuracy, and eliminates the C-arm from the operating field. Selection by 76.1% of the response “decreased radiation exposure” highlights a major occupational hazard of spine surgery that can be mitigated in part by the use of spinal navigation technology. This advantage becomes more evident with increased use as surgeons with extensive navigation experience almost unanimously considered decreased radiation exposure a strength of navigation technology.

In addition, 29.1% of surveyed surgeons with more navigation experience felt that keeping the C-arm out of the operative field was a major advantage. Elimination of the C-arm from the operative field can prevent the surgeon from assuming uncomfortable positions to reach the operative target, as well as allow a second surgeon to assist from the opposite side. It is interesting to note that very few of the surgeons with no navigation experience believed that keeping the C-arm out of the field was a major strength, suggesting that without having experienced the operative room free of the C-arm, the surgeon without spinal navigation experience may not appreciate the advantages of the improved ergonomics. Among the spine surgeries selected as best uses of spinal navigation, there was the common thread of procedures that typically require instrumentation and/or large amounts of fluoroscopy. We anticipate an increased use of minimally invasive techniques in the near future, which in turn will increase dependence on intraoperative fluoroscopy and instrumentation.