A prospective, randomized, controlled trial of robot-assisted vs freehand pedicle screw fixation in spine surgery

Abstract

Background: The purpose of this study was to compare the accuracy and safety of an instrumented posterior lumbar interbody fusion (PLIF) using a robot-assisted minimally invasive (Robot-PLIF) or a conventional open approach (Freehand-PLIF).

Methods: Patients undergoing an instrumented PLIF were randomly assigned to be treated using a Robot-PLIF (37 patients) and a Freehand-PLIF (41 patients).

Results: For intrapedicular accuracy, there was no significant difference between the groups (P = 0.534). For proximal facet joint accuracy, none of the 74 screws in the Robot-PLIF group violated the proximal facet joint, while 13 of 82 in the Freehand-PLIF group violated the proximal facet joint (P < 0.001). The average distance of the screws from the facets was 5.2 ± 2.1 mm and 2.7 ± 1.6 mm in the Robot-PLIF and Freehand-PLIF groups, respectively (P < 0.001).

Conclusion: Robotic-assisted pedicle screw placement was associated with fewer proximal facet joint violations and better convergence orientations.

Keywords: free-hand technique; posterior lumbar interbody fusion; proximal facet joint violation; randomized controlled trial; robot-assisted pedicle screw fixation.