The Use of Intraoperative CT and Navigation for the Treatment of Spinal Deformity in Open and Minimally Invasive Surgery
The accuracy of pedicle screw placement depends on the experience of the surgeon and the method used. Published rates of accuracy hold thoracolumbar freehand screw placement at 72% to 94%.1 Use of fluoroscopy may increase accuracy to 84% to 94%.2 It is important to note that not all malpositioned pedicle screws require revision surgery, and published rates of revision range from 2% to 8%.3 Even with such low rates, such revisions, on average, cost the health care system $23,762.3 In the aggregate, such costs are undesirable, as are potential complications such as dural tear or neurologic injury. Busy spine centers may consider the utility of intraoperative CT scanning for screw checking or three-dimensional navigation to improve the accuracy of spinal instrumentation.
Intraoperative CT scanning and associated navigation tools have evolved over the past 10 years with improved accuracy. In part, acceptance of navigation has lagged as the result of work flow in the operating room and time constraints. Additionally, intraoperative CT scanning in the prone position has enhanced the accuracy of navigation over preoperative scans, which are obtained supine. Modern intraoperative navigation and robot-assisted navigation can enhance surgical accuracy and improve the safety profile of complex spinal surgery (Figure 1).