ABSTRACT
Pedicle screw fixation is a spinal fusion technique that involves the implantation of screws into vertebral pedicles to restrict movement between those vertebrae. The objective of this research is to measure pedicle screw placement accuracy using a novel automated measurement system that directly compares the implanted screw location to the planned target in all three anatomical views. Preoperative CT scans were used to plan the screw trajectories in 122 patients across four surgical centers. Postoperative scans were fused to the preoperative plan to quantify placement accuracy using an automated measurement algorithm. The mean medial-lateral and superior-inferior deviations in the pedicle region for 500 screws were 1.75 ± 1.36 mm and 1.52 ± 1.26 mm, respectively. These deviations were measured using an automated system and were statistically different from manually determined values. The uncertainty associated with the fusion of preoperative to postoperative images was also quantified to better understand the screw-to-plan accuracy results. This study uses a novel automated measurement system to quantify screw placement accuracy as it relates directly to the planned target location, instead of analyzing for breaches of the pedicle, to quantify the validity of using of a robotic-guidance system for accurate pedicle screw placement.
Subject(s)
Pedicle Screws , Robotics , Spinal Fusion , Surgery, Computer-Assisted , Humans , Spinal Fusion/methods , Fluoroscopy/methods , Spine/diagnostic imaging , Spine/surgery , Surgery, Computer-Assisted/methods , Retrospective Studies , Lumbar Vertebrae/surgeryABSTRACT
Herniated discs in the lumbar spine are common, however, extraforaminal disc herniations are less frequently encountered. Occasionally, rare disc herniations can mimic other pathologies such as nerve tumor. We present such case and a review of similar cases in the scientific literature. A 71-year-old male who presented with back pain and right-side sciatic pain. Magnetic resonance imaging revealed a fusiform enhancing 3 cm × 2 cm lesion that was concerning for a nerve sheath tumor. A minimally invasive lateral trans-psoas approach was performed for a biopsy that revealed disc fragments and a full resection was performed. The patient's symptoms improved at follow-up. Although uncommon, extraforaminal disc herniations can be mistaken for peripheral nerve tumors on imaging. The spine surgeon should remain vigilant about these entities and plan the surgical treatment accordingly.
ABSTRACT
OBJECTIVE: Robotics is a major area for research and development in spine surgery. The high accuracy of robot-assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems. METHODS: An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days. RESULTS: In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases. CONCLUSIONS: The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery.
ABSTRACT
Robotic-assisted spine surgery has a number of potential advantages, including more precise pre-operative planning, a high degree of accuracy in screw placement, and significantly reduced radiation exposure to the surgical team. While the current primary goal of these systems is to improve the safety of spine surgery by increasing screw accuracy, there are a number of technical errors that may increase the risk of screw malposition. Given the learning curve associated with this technology, it is important for the surgeon to have a thorough understanding of all required steps. In this article, we will demonstrate the setup and workflow of a combined navigation and robotic spine surgery platform using the Mazor X Stealth Edition (MXSE) system to place cortical-based trajectory (CBT) screws, including a review of all technical tips and pearls to efficiently perform this procedure with minimal risk of screw malposition. In this article, we will review surgical planning, operating room setup, robotic arm mounting, registration, and CBT screw placement using the MXSE system.