gms | German Medical Science

54. Jahrestagung der Norddeutschen Orthopädenvereinigung e. V.

Norddeutsche Orthopädenvereinigung

16.06. bis 18.06.2005, Hamburg

Biomechanical comparison of radiolucent peek cervical spine interbody fusion cages

Meeting Abstract

  • corresponding author P. Schleicher - Charité Universitätsmedizin Berlin, Centrum für Muskuloskeletale Chirurgie, Berlin
  • R. Pflugmacher
  • M. Scholz
  • T. Eindorf
  • F. Kandziora
  • N. Haas

Norddeutsche Orthopädenvereinigung. 54. Jahrestagung der Norddeutschen Orthopädenvereinigung e.V.. Hamburg, 16.-18.06.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc05novP24

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter:

Veröffentlicht: 13. Juni 2005

© 2005 Schleicher et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen ( Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.



Study Design

Biomechanical study of PEEK cervical spine interbody fusion cages (CSIFC) using an in-vitro method.


The purpose of this study was to evaluate the segmental stability provided by two newly developed PEEK CSIFC and to compare it to the native motion segment

Summary and Background Data

Despite the initial favourable results, the long-term effects of metallic cage devices on spinal motion segments are still unknown. Furthermore, short comings of metallic cages like migration, adjacent level degeneration, stenotic myelopathy and artefacts in postoperative radiological assessment have already been reported. Radiolucent cages have been designed to avoid some of these complications.

Material and Methods

8 human cervical spines (C2 to C7) were tested in flexion, extension, axial rotation, and lateral bending with a non-destructive stiffness method using a nonconstrained testing apparatus. First the motion segment C5/C6 was tested intact. After complete discectomy the following groups were evaluated: (1) NEOCIF cervical PEEK cage provided by Biomet Inc. (2) Stryker Solis PEEK Cage. The mean apparent stiffness, ROM (range of motion), NZ (neutral zone) and EZ (elastic zone) were calculated from the corresponding load-displacement curves.


No significant difference in ROM and segmental stiffness between the Stryker Solis cage and the Biomet PEEK cervical cage could be determined. The Stryker significantly (p<0.05) failed to restore ROM and stiffness in extension in comparison to the intact motion segment. It showed significant higher results for neutral Zone in flexion, bending and rotation compared to the native motion segment.


In this study, two types of PEEK cervical interbody fusion cages were compared in regards of biomechanical stability. A statistical significant difference between these two implants could not be found, although the Biomet implant showed better results regarding the ability to restore native stability.