Clinical Acceptance and Accuracy Assessment of Spinal Implants Guided with SpineAssist Surgical Robot: Retrospective Study Dennis P. Devito, MD; Leon Kaplan, MD; Rupert Dietl, MD; Michael Pfeiffer, MD; Dale Horne, MD; Boris Silberstein, MD; Mitchell Hardenbrook, MD; George Kiriyanthan, MD; Yair Barzilay, MD; Alexander Bruskin, MD; Dieter Sackerer, MD; Vitali Alexandrovsky, MD; Carsten Stüer, MD; Ralf Burger, MD; Johannes Maeurer, MD; Donald G. Gordon, MD; Robert Schoenmayr, MD; Alon Friedlander, MD; Nachshon Knoller, MD; Kirsten Schmieder, MD; Ioannis Pechlivanis, MD; In-Se Kim, MD; Bernhard Meyer, MD; Moshe Shoham, DSc Posted: 12/06/2010; Spine. 2010;35(24):2109-2115. © 2010 Lippincott Williams & Wilkins Abstract and Introduction Abstract Study Design. Retrospective, multicenter study of robotically-guided spinal implant insertions. Clinical acceptance of the implants was assessed by intraoperative radiograph, and when available, postoperative computed tomography (CT) scans were used to determine placement accuracy. Objective. To verify the clinical acceptance and accuracy of robotically-guided spinal implants and compare to those of unguided free-hand procedures. Summary of Background Data. SpineAssist surgical robot has been used to guide implants and guide-wires to predefined locations in the spine. SpineAssist which, to the best of the authors' knowledge, is currently the sole robot providing surgical assistance in positioning tools in the spine, guided over 840 cases in 14 hospitals, between June 2005 and June 2009. Methods. Clinical acceptance of 3271 pedicle screws and guide-wires inserted in 635 reported cases was assessed by intraoperative fluoroscopy, where placement accuracy of 646 pedicle screws inserted in 139 patients was measured using postoperative CT scans. Results. Screw placements were found to be clinically acceptable in 98% of the cases when intraoperatively assessed by fluoroscopic images. Measurements derived from postoperative CT scans demonstrated that 98.3% of the screws fell within the safe zone, where 89.3% were completely within the pedicle and 9% breached the pedicle by up to 2 mm. The remaining 1.4% of the screws breached between 2 and 4 mm, while only 2 screws (0.3%) deviated by more than 4 mm from the pedicle wall. Neurologic deficits were observed in 4 cases yet, following revisions, no permanent nerve damage was encountered, in contrast to the 0.6% to 5% of neurologic damage reported in the literature. Conclusion. SpineAssist offers enhanced performance in spinal surgery when compared to free-hand surgeries, by increasing placement accuracy and reducing neurologic risks. In addition, 49% of the cases reported herein used a percutaneous approach, highlighting the contribution of SpineAssist in procedures without anatomic landmarks. Introduction This article summarizes the activity of the SpineAssist surgical robot which, to the best of the authors' knowledge, is currently the only robot in use to assist spine surgeries. The development of SpineAssist started some 7 years ago and went through several developmental phases that have been previously reported. [1,2] Since reaching specific developmental and regulatory milestones, SpineAssist has been applied in operating rooms in the United States, Germany, and Israel. Reports of SpineAssist performance [3–8] have been published, where each surgeon individually recounted his own experiences. The current article reports on the clinical experience obtained with this surgical robot and summarizes its activities, between June 2005 and June 2009. Performing spine surgery is a delicate and hazardous procedure due to its proximity to both the central nervous system and main blood vessels. The unsatisfactory rate of misplaced screws in spinal fusion procedures inspired the emergence of a proposal to robotically guide pedicle screw insertion. To effectively achieve this goal, a number of issues had to be addressed, including screw trajectory planning, typically performed on preoperative computed tomography (CT) images, registration of the preoperative plan with the intraoperative