gms | German Medical Science

63rd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Japanese Neurosurgical Society (JNS)

German Society of Neurosurgery (DGNC)

13 - 16 June 2012, Leipzig

Safety and accuracy comparison of robot-assisted and fluoroscopy-guided pedicle screw insertion

Meeting Abstract

  • B. Schatlo - Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Suisse
  • M. Kotowski - Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Suisse
  • G. Molliqaj - Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Suisse
  • K. Schaller - Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Suisse
  • E. Tessitore - Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Suisse

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 63. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie (JNS). Leipzig, 13.-16.06.2012. Düsseldorf: German Medical Science GMS Publishing House; 2012. DocDO.08.09

DOI: 10.3205/12dgnc075, URN: urn:nbn:de:0183-12dgnc0752

Published: June 4, 2012

© 2012 Schatlo et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

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Objective: Recent years have been marked by efforts to improve pedicle-screw placement in spinal instrumentation. A robotic spine surgery system was developed to increase the accuracy of pedicle screw trajectories and a number of reports on the system are surfacing with a range of different opinions. We compared the performance of the system with a cohort of patients who underwent freehand (i.e. fluoroscopy-guided only) spinal instrumentation.

Methods: Patients requiring elective spine surgery with posterior instrumentation were included in the study. In the robot cohort, pedicle screw trajectories were planned on the MAZOR (SpineAssist, Israel) image-processing unit prior to surgery. Using a modified intraoperative fluoroscope and a spinous-process-clamp, we performed an intraoperative dataset matching and screws were inserted guided by the robot arm. Freehand screws were inserted using anatomical landmarks and lateral fluoroscopy. Accuracy of screw placement was assessed using a scale by Gertzbein and Robbins (from A to E. A: perfect intrapedicular localization, E: > 6 mm deviation from ideal intrapedicular trajectory).

Results: Ninety-five patients were included in the study, 40 of which were operated using robot-guidance. A total of 174 screws were placed using robot-guidance and 327 screws were placed using anatomical landmarks and lateral fluoroscopy only. In the robot group, the A-graded screws (perfect intrapedicular position) had a higher relative frequency (80.5 vs. 72.5%, p = 0.05). Conversely, B-graded screws were relatively more frequent in the fluoroscopy/freehand group (11.5 vs 15.3%, p = 0.01). Of note, this difference became insignificant when the overall scores were divided into subgroups of thoracic, lumbar or sacral segments.

Conclusions: We demonstrate that the use of the MAZOR system for robot-guided pedicle screw placement is safe and useful. Moreover, it can be associated with other techniques such as vertebroplasty, PLIF or TLIF. In our experience, one of the merits of this system lies in its ability to facilitate access to regions where pedicle anatomy is difficult to visualize, such as the upper thoracic spine or in revision surgeries.