gms | German Medical Science

61st Annual Meeting of the German Society of Neurosurgery (DGNC) as part of the Neurowoche 2010
Joint Meeting with the Brazilian Society of Neurosurgery on the 20 September 2010

German Society of Neurosurgery (DGNC)

21 - 25 September 2010, Mannheim

Biomechanical comparison of posterior cervicothoracic instrumentation techniques after one level laminectomy and facetectomy

Meeting Abstract

  • Matthias Setzer - H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program and Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL, USA; Department of Neurosurgery, J. W. Goethe University,Frankfurt am Main, Germany
  • Mohammed Eleraky - H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program and Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL, USA
  • Ali A. Baaj - H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program and Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL, USA
  • Ioannis Papanastasssiou - H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program and Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL, USA
  • Bryan Conrad - Department of Orthopaedics, University of Florida, Gainesville, FL, USA
  • Frank D. Vrionis - H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program and Department of Neurosurgery, University of South Florida College of Medicine, Tampa, FL, USA

Deutsche Gesellschaft für Neurochirurgie. 61. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC) im Rahmen der Neurowoche 2010. Mannheim, 21.-25.09.2010. Düsseldorf: German Medical Science GMS Publishing House; 2010. DocP1795

doi: 10.3205/10dgnc266, urn:nbn:de:0183-10dgnc2660

Published: September 16, 2010

© 2010 Setzer 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

Text

Objective: Posterior instrumentation is the preferred method of fixation in the unstable cervicothoracic junction (CTJ). Several posterior rod constructs of different diameters and configurations are available for instrumentation across the cervicothoracic junction. The objective of this study was to compare the biomechanical stability of various posterior instrumentation techniques that cross the CTJ after a two column injury by complete removal of the posterior elements at C7.

Methods: Eight fresh frozen human cadaveric spines (C3–T4) were used. After the intact spine analysis, each specimen was destabilized (C7 laminectomy and bilateral facetectomies) and reconstructed as follows: Group 1-Posterior instrumentation C5–T2 with a 3.5 mm rod. Group 2- Posterior instrumentation C5–T2 with a transitional rod (3.5 mm to 5.5 mm). Group 3- Posterior instrumentation C5–T2 with side to side rod connector (3.5 mm to 5.5m). All reconstructed groups were tested with posterior instrumentation using the Cervifix system (Synthes Inc. West Chester, PA, USA). We hypothesized that group 2 is the most stable.

Results: Following laminectomy, facetectomy and application of the instrumentation, there was a decrease in range of motion for all the treatment groups compared to the intact spine. This trend was observed in all three planes of motion, but was only significant in right/left lateral bending and flexion (for transitional rod only). Although, the instrumented spines were stiffer than the intact spine in right/left axial rotation, flexion and extension, these differences did not reach statistical significance. Based on observation during the testing, it was evident that in the implanted spines, the majority of the motion that did occur was localized at the segments adjacent to the instrumented levels.

Conclusions: Based on the results of this investigation, the biomechanical stability of the transitional rod, side to side connector ("wedding band") and 3.5 mm rods appear to be similar.