Accuracy of robot-assisted pedicle screw placement for adolescent idiopathic scoliosis in the pediatric population

Abstract

This is a retrospective review of pedicle screw placement in adolescent idiopathic scoliosis (AIS) patients under 18 years of age who underwent robot-assisted corrective surgery. Our primary objective was to characterize the accuracy of pedicle screw placement with evaluation by computed tomography (CT) after robot-assisted surgery in AIS patients. Screw malposition is the most frequent complication of pedicle screw placement and is more frequent in AIS. Given the potential for serious complications, the need for improved accuracy of screw placement has spurred multiple innovations including robot-assisted guidance devices. No studies to date have evaluated this robot-assisted technique using CT exclusively within the AIS population. Fifty patients were included in the study. All operative procedures were performed at a single institution by a single pediatric orthopedic surgeon. We evaluated the grade of screw breach, the direction of screw breach, and the positioning of the patient for preoperative scan (supine versus prone). Of 662 screws evaluated, 48 screws (7.2 %) demonstrated a breach of greater than 2 mm. With preoperative prone position CT scanning, only 2.4 % of screws were found to have this degree of breach. Medial malposition was found in 3 % of screws, a rate which decreased to 0 % with preoperative prone position scanning. Based on our results, we conclude that the proper use of image-guided robot-assisted surgery can improve the accuracy and safety of thoracic pedicle screw placement in patients with adolescent idiopathic scoliosis. This is the first study to evaluate the accuracy of pedicle screw placement using CT assessment in robot-assisted surgical correction of patients with AIS. In our study, the robot-assisted screw misplacement rate was lower than similarly constructed studies evaluating conventional (non-robot-assisted) procedures. If patients are preoperatively scanned in the prone position, the misplacement rate is further decreased.

Current applications of robotics in spine surgery: a systematic review of the literature

“…Macke et al also found a decrease in misplacements when comparing the first and last third of their cohort (9.6% vs 7.4%). 22 However, Ringel et al stated that accuracy did not improve over the course of their study, although no specific data were provided.…”

“…2,5,6,9,[11][12][13][14][15]17,21,22,24,25,[27][28][29][30][31][35][36][37] Twenty-one of these studies used variations of the robot developed by Mazor, whereas 1 study evaluated the ROSA robot. Twenty-one studies evaluated pedicle screw accuracy, whereas Dreval et al evaluated both pedicle screws and guided oblique lumbar interbody fusion (GO-LIF) screws, 6 and Bederman et al evaluated the accuracy of S2-alar-iliac screw placement.…”

“…5,10,12,15,22,24,27,29 Devito et al found that the ability to place screws robotically was 83.7% in their total cohort, but increased to a 90.8% execution rate when they looked at their most recent procedures. 5 In addition, time per screw placement decreased from 13.5 minutes for single-level cases (4 minutes per screw in multilevel cases) to 10.6 minutes (2 minutes in multilevel cases).…”

“…1,5,9,17,21,22,24,25,27,28,30,35 Reasons for aborting the robotic procedure included failure of registration software and failure to obtain adequate fluoroscopic images. In several studies, soft-tissue pressure on the guiding arm led to inaccurate placement.…”

Minimally invasive versus conventional fixation of tracer in robot-assisted pedicle screw insertion surgery: a randomized control trial

“…Briefly, robot-assisted spinal operation involves the preoperative or intraoperative acquisition of images and image-guided surgery after registration and calibration [9,10].…”