Analysis of the accuracy between orthopedic robot-assisted and traditional manual pedicle screw placement techniques in adult degenerative scoliosis posterior surgery

Abstract

Objective: To comparing the accuracy of pedicle screw placement in posterior surgery for adult degenerative scoliosis (ADS) between robotic-assisted and traditional freehand techniques. Methods: This retrospective study included 92 patients with ADS who underwent posterior spinal surgery at the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital) between March 2019 and December 2023. There were 19 males and 73 females with a mean age of (63.6±9.8) years. The patients were divided into two groups based on the technique used for pedicle screw placement: robot-assisted group (34 cases) and manual group (58 cases). Operative duration, intraoperative blood loss, facet joint violation, postoperative complications, magnitude of curve correction, visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores preoperatively, 1 week postoperatively, and 1 month postoperatively were compared and analyzed between the two groups. The Gertzbein-Robbins classification criteria was used to assess the accuracy of screw placement. Results: Differences in baseline data, operative duration, intraoperative blood loss, magnitude of curve correction, and VAS and ODI scores preoperatively, 1 week postoperatively, and 1 month postoperatively between the two groups exhibited no statistically significant differences (all P>0.05). The accuracy of pedicle screw placement in the robot-assisted group was significantly higher than that in the manual group [90.9% (416/458) vs 80.1% (697/870), P<0.001]. In terms of surgical segments, in T1-T12 and L1-S1 segments, the accuracy of pedicle screw placement in the robot group were both significantly higher than those in the control group [91.5% (130/142) vs 77.8% (186/239), P=0.001; 90.3% (271/300) vs 80.8% (502/621), P<0.001]. However, no significant differences was observed in the accuracy of S2-alar-iliac (S2AI) screw placement between the two groups [90.0%(9/10) vs 93.8%(15/16), P=0.727]. Moreover, no significant differences was found in the deviation direction of the cortical screw penetration between both groups (P=0.133). Significant differences were observed in the accuracy of screw placement between the Nash Moe 2 and 3 vertebral bodies in the robot group compared with those in the control group [88.9% (88/99) vs 71.0% (115/162), P=0.001; 89.2% (83/93) vs 60.2% (68/113), P<0.001]. Additionally, the incidence and grade of facet joint violation in the manual group were both significantly higher than those in the robot-assisted group (both P<0.001). No statistically significant differences was identified in postoperative complications between the two groups (P=0.841). Conclusion: It suggests that robot-assisted pedicle screw placement in posterior surgery for patients with ADS can significantly improve the accuracy of screw placement and reduce the incidence of facet joint violation.