title: Micro-CT evaluation of asymmetrical ovine intervertebral disc height loss from surgical approach.
abstract: The primary goal of this study is to clearly define and evaluate new intervertebral disc height parameters in analysing the morphological pathology of disc degeneration for application in damage model and regeneration therapy development, as well as applying traditional variables to 3-D characterization methods.
  
  
  
  A posterolateral surgical approach was used to induce disc degeneration in an ovine model. At 12-months post-operation, sheep vertebral segments were removed and characterized using micro-CT to evaluate disc height parameters in regard to injury localization.
  
  
  
  Statistically significant differences between the disc height loss of the left and right side of the disc, consistent with the lateral surgical approach used were seen using the modified average disc height method by Dabbs et al. However, convexity index and the newly proposed Cross Tilt Index did not conclusively demonstrate a difference.
  
  
  
  Two-dimensional morphological evaluations can be applied in 3-D to provide a more complete picture of disc height loss for injury models. New 3-D parameters that are tailored to the type of surgical approach used should be investigated, with the 9-point system described herein providing a useful basis for derived values. Additionally, the surgical approach chosen when artificially injuring the disc can result in asymmetrical degeneration, as indicated by uneven disc height loss.
authors.affiliation: Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany.|Department of Chemical and Biomolecular Engineering, University of Tennessee Knoxville, Knoxville, TN, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Ludtka
authors.affiliation: Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany. stefan.schwan@imws.fraunhofer.de.|Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany. stefan.schwan@imws.fraunhofer.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schwan
authors.affiliation: Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany.|Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Friedmann
authors.affiliation: Translational Center for Regenerative Medicine, University of Leipzig, Leipzig, Germany.|Department of Veterinary Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: Walther
authors.initials: W
authors.lastname: Brehm
authors.affiliation: Department of General Surgery, BG Bergmannstrost Clinic, Halle, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Wiesner
authors.affiliation: Department of General Surgery, BG Bergmannstrost Clinic, Halle, Germany.|Department of Neurosurgery, University of Helsinki, Helsinki, Finland.
authors.forename: Felix
authors.initials: F
authors.lastname: Goehre
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D021621:Imaging, Three-Dimensional; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000473:pathology*; D012756:Sheep / Q000601:surgery*; D055114:X-Ray Microtomography
keywords: Animal model; Disc herniation; IVD degeneration; Intervertebral disc height; Micro-computed tomography; µCT