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

Biological sealing of annulus fibrosus defects with a polymer-based implant in an ovine model

Meeting Abstract

  • Aldemar A. Hegewald - Department of Neurosurgery, Innsbruck Medical University, Innsbruck, Austria; Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
  • Fabian Medved - Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
  • Daxiong Feng - Spinal Surgery Department, The Affiliated Hospital of Luzhou Medical College Luzhou, Sichuan Province, PR China; Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
  • Genevieve Schindler - Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
  • Kirsten Schmieder - Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
  • Claudius Thomé - Department of Neurosurgery, Innsbruck Medical University, Innsbruck, Austria

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. DocV1655

DOI: 10.3205/10dgnc128, URN: urn:nbn:de:0183-10dgnc1287

Published: September 16, 2010

© 2010 Hegewald 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: Spinal surgery procedures for disc herniation can be complicated by two major problems: (1) re-herniation through the annulus fibrosus defect and (2) painful degeneration of the spinal segment. Therefore, we examined a textile absorbable polymer-based biomaterial for its utility to seal annulus fibrosus defects aiming for (a) preventing re-herniation and (b) providing a containment strategy for potential nucleus implants.

Methods: Via a left retroperitoneal approach the discs L3/4 and L4/5 of 20 adult merino sheep were approached. A standardized box defect was applied to the annulus of each disc, followed by randomized insertion of the annulus implant in one of the defects. Explantation of the spinal segments was conducted after 2, 6 and 12 weeks. Evaluation of the discs were performed by magnetic resonance imaging, histological analysis and pressure-volume testing.

Results: At all time points, no implant dislocations were detected with mri. Contrary to the control defect, histological analysis of the annulus implants showed proper nucleus containment. In addition, considerable cell in-growth and matrix assembling in the biomaterial was observed. However, a smear effect was noticed at the outer absorbable layers of the implant. Pressure-volume testing showed an increasing pressure resistance with time, but after 12 weeks no advantage in comparison to the control defect could be noticed.

Conclusions: The presented annulus sealing system showed promising results with regard to biocompatibility and mechanical function in an ovine model. Optimization of the absorbable component and design of an adequate application and fixation system, however, are mandatory before clinical application.