Accuracy of pedicle screw insertion in single-level lumbar interbody fusion: comparison before and after the introduction of intraoperative three-dimensional computed tomography navigation.

PURPOSE: This study aimed to evaluate pedicle screw placement accuracy, surgical complications, and reoperation rates in patients undergoing single-level lumbar interbody fusion before and after the introduction of an intraoperative three-dimensional computed tomography (3D-CT: O-arm) navigation system at our institution.

METHODS

This retrospective study included patients who underwent single-level lumbar interbody fusion for lumbar degenerative disease at the L4/5 or L5/S level. Patients treated after the introduction of the O-arm system were assigned to the O-arm group (group O), whereas those treated before its introduction were assigned to the freehand group (group F). Group O consisted of 344 consecutive cases treated between January 2016 and March 2020. Group F consisted of 304 consecutive cases treated between April 2009 and December 2011. Pedicle screw perforation was assessed using postoperative CT, and reoperations for screw malposition were recorded.

RESULTS

The overall rate of screw perforation on postoperative CT was significantly lower in group O than in group F (p < 0.001). Medial perforation occurred most frequently in group F, whereas only two cases were observed in group O. No patients in group O required reoperation for screw malposition, while four patients in group F underwent reoperation, representing a significant difference between groups (p < 0.05).

CONCLUSION

Reoperations due to pedicle screw malposition were significantly less frequent in the O-arm group than in the freehand group. The introduction of intraoperative 3D-CT navigation was associated with reduced surgical invasiveness and a lower incidence of implant-related complications, including screw-induced nerve injury, thereby improving surgical safety.