Polyetheretherketone (PEEK) Spacers for Anterior Cervical Fusion: A Retrospective Comparative Effectiveness Clinical Trial

Johannes Lemcke*, 1, Ferass Al-Zain1, Ullrich Meier1, Olaf Suess2
1 Department of Neurosurgery, Unfallkrankenhaus Berlin, Germany
2 Department of Neurosurgery, Charité-Universitätsmedizin Berlin, Germany and Departement of Neurotraumatology and Spine Surgery, German Red Cross Hospital Westend, Berlin, Germany

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 838
Abstract HTML Views: 287
PDF Downloads: 192
Total Views/Downloads: 1317
Unique Statistics:

Full-Text HTML Views: 543
Abstract HTML Views: 199
PDF Downloads: 142
Total Views/Downloads: 884

Creative Commons License
© Lemcke et al.; Licensee Bentham Open.

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial ( which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.

* Address correspondence to this author at the Department of Neurosurgery, Unfallkrankenhaus Berlin, Warener Straße 7, D-12683 Berlin, Germany; Tel: +49 (0)30 5681 3701; Fax: +49 (0)30 5681 3703: E-mail:



Anterior cervical decompression and fusion (ACDF) is the standard surgical treatment for radiculopathy and myelopathy. Polyetheretherketone (PEEK) has an elasticity similar to bone and thus appears well suited for use as the implant in ACDF procedures. The aim of this study is to examine the clinical and radiographic outcome of patients treated with standing alone PEEK spacers without bone morphogenic protein (BMP) or plating and to examine the influence of the different design of the two spacers on the rate of subsidence and dislocation.


This retrospective comparative study reviewed 335 patients treated by ACDF in a specialized urban hospital for radiculopathy or myelopathy due to degenerative pathologies. The Intromed PEEK spacer was used in 181 patients from 3/2002 to 11/2004, and the AMT SHELL spacer was implanted in 154 patients from 4/2004 to 12/2007. The follow-up rate was 100% at three months post-op and 82.7% (277 patients) at one year. The patients were assessed with the Japanese Orthopedic Association (JOA) questionnaire and radiographically.


At the one-year follow-up there were 118/277 patients with an excellent clinical outcome on the JOA, 112/277 with a good outcome, 20/277 with a fair outcome, and 27/277 with a poor outcome. Subsidence was observed in 13.3% of patients with the Intromed spacer vs 8.4% of the patients with the AMT SHELL. Dislocation of the spacer was observed in 10 of the 181 patients with Intromed spacers but in none of the 154 patients with Shell spacers.


The study demonstrates that ACDF with standing alone PEEK cages leads to excellent and good clinical outcomes. The differences we observed in the subsidence rate between the two spacers were not significant and cannot be related to a single design feature of the spacers.

Keywords: Anterior cervical decompression and fusion, ADCF, PEEK spacer, subsidence, dislocation.