A Novel Mobile Device-Based Navigation System for Placement of Posterior Spinal Fixation

Spinal navigation technology has revolutionized the field of spine surgery. However, adoption has not been universal. Reasons include cost, interruption in surgical workflow, increased OR time, and potential implant incompatibility, among others. A technology that maintains performance but alleviates these drawbacks would be valuable. A mobile device-based navigation system has been developed which relies on the iOS platform and the gyroscopic-on-chip technology, therein to guide accurate placement of pedicle screws. This system maintains a minimal footprint and resolves difficulty with line-of-sight interruption and attention shift.

To evaluate the accuracy and reliability of this device in a preclinical setting.

A cadaver study was performed involving 13 surgeons placing 26 pedicle screws using the novel assistive technology. CT scans were then performed, and accuracy was assessed by designating each screw a Gertzbein-Robbins score. In addition, bench top table testing was performed. This consisted of 360 tests of both the accuracy of the device's pitch and roll, corresponding to the rotation about the device's x-axis and y-axis, respectively.

The mean Gertzbein-Robbins score of the 26 screws placed in the cadaver study was 1.29. The mean deviation from centerline pedicle placement was 0.66 mm, with a standard deviation of 1.52 mm. The bench top study results included a mean pitch error of 0.17° + 0.09° and a mean roll error of 0.29 + 0.21.

The novel mobile device-based navigation system for placement of pedicle screws presented here demonstrates high levels of accuracy and reliability in the preclinical setting.