A comparative study of robot-assisted and freehand pedicle screw placement in upper thoracic surgery

Abstract

To compare the safety and accuracy of pedicle screw placement assisted by robot system with freehand pedicle screw placement in upper thoracic surgery. Between December 2017 and December 2019, 39 cases with upper thoracic pedicle screw internal fixation were included in the study, including 19 cases in robot group (group A, robot assisted pedicle screw placement) and 20 cases in freehand group (group B, freehand pedicle screw placement). There were 104 screws implanted in group A and 108 screws in group B. There was no significant difference in age, gender composition, body mass index, disease type, number of screws implanted, and segmental distribution between the two groups ( P>0.05). The operation time, intraoperative blood loss, and postoperative drainage were recorded and compared between the two groups. CT scan was performed in all patients at 2 days after operation to evaluate the screw accuracy based on the Gertzbein-Robbins grading standard. The operation time of group A was significantly longer than that in group B ( t=2.759, P=0.009). There was no significant difference in intraoperative blood loss and postoperative drainage between the two groups ( t=-0.796, P=0.431; t=-0.814, P=0.421). At 2 days after operation, according to Gertzbein-Robbins grading standard, the accuracy of pedicle screw implantation in group A were grade A in 94 screws, grade B in 9 screws, and grade C in 1 screw; and in group B were grade A in 72 screws, grade B in 26 screws, grade C in 9 screws, and grade D in 1 screw; the difference between the two groups was significant ( Z=4.257, P=0.000). The accuracy rate of group A was 99.04%, and that of group B was 90.74%, showing significant difference ( χ 2=7.415, P=0.006). Compared with traditional freehand pedicle screw placement, robot-assisted pedicle screw placement significantly improves the accuracy and safety of screw placement without increasing the bleeding and postoperative drainage.