gms | German Medical Science

65th Annual Meeting of the German Society of Neurosurgery (DGNC)

German Society of Neurosurgery (DGNC)

11 - 14 May 2014, Dresden

Autograft vs. alloplastic fusion material in posterior C1-2 Fusion with C1 lateral mass and C2 isthmic screws: extended series

Meeting Abstract

  • Andreas Reinke - Neurochirurgische Klinik, Technische Universität München
  • Michael Behr - Neurochirurgische Klinik, Technische Universität München
  • Alexander Preuss - Neurochirurgische Klinik, Technische Universität München
  • Florian Ringel - Neurochirurgische Klinik, Technische Universität München
  • Bernhard Meyer - Neurochirurgische Klinik, Technische Universität München
  • Michael Stoffel - Neurochirurgische Klinik, Technische Universität München; Klinik für Neurochirurgie, Helios Klinikum Krefeld

Deutsche Gesellschaft für Neurochirurgie. 65. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC). Dresden, 11.-14.05.2014. Düsseldorf: German Medical Science GMS Publishing House; 2014. DocMO.18.05

doi: 10.3205/14dgnc106, urn:nbn:de:0183-14dgnc1067

Published: May 13, 2014

© 2014 Reinke et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: For atlantoaxial fusion, the dorsal C1/2 stabilisation in Harms technique is often used. For achieving a sufficient fusion it is already well known that the use of grafts is indispensible. Literature shows a fusion rate of nearly 100% for bone grafting with iliac crest autograft in larger series. Alloplastic fusion material appears as a potential alternative. Accordingly, we already described our preliminary experience with both materials a few years ago in a small cohort. Now, we present our final assessment in a large cohort of patients.

Method: 83 patients treated at our institution since May 2006 were included. Screw position and reduction/realignment were assessed by postoperative thin-cut CT scans. For follow-up, radiographic data and the clinical status were collected. Material failure was excluded by radiographic parameters like screw loosening, dislocation, or fracture and by clinical status.

Results: A total of 83 (35 females and 48 males) patients requiring atlantoaxial stabilisation for instabilities were included. Mean age was 65 years (range 4–92 years). 55 patients were operated for traumatic, nine for neoplastic, three for infectious, nine for degenerative, and seven for congenital instabilities, respectively. No neurological or vascular injuries occurred. 16 patients were treated with a bicortical iliac crest allograft and 67 with an alloplastic implant (36 β-Tricalcium-phosphat (chronOS®), 31 Hydroxylapatit (Actifuse®)). After a mean follow-up period of 13 months (range 1–41) our follow-up rate was 75% (62 of 83). 11 patients treated with autologous bone were available for the follow-up examination (69%). From these 11 patients, 10 had already a radiographic and clinical fusion (91%). Only one Patient had a recurrent neck pain as a sign for non-fusion without radiological findings. In the group of patients treated with an alloplastic implant, we also achieved a fusion rate of 90%. Five patients had radiographic (screw loosening or pullout) as well as clinical signs of non-fusion. 51 of all 67 patients with alloplastic implant were available for follow-up (76%).

Conclusions: According to our results, alloplastic fusion material in combination with a Harms instrumentation of C1/2 provides comparable clinical and radiological results to the gold standard, i.e. iliac crest autograft. Limitations of this study are primarily due to its retrospective nature and the drop-out ratio during follow-up.