PEEK Cages versus Titanium-Coated PEEK Cages in Single-Level Anterior Cervical Fusion: A Randomized Controlled Study

Abstract

Background The implantation of a spacer is a common practice after anterior diskectomy in cervical spine. Polyether ether ketone (PEEK) cages have replaced titanium implants due to their better radiologic visibility and appearance in postoperative magnetic resonance imaging (MRI) scans. However, PEEK showed apparently higher nonunion rates than titanium cages. The aim of the study was to evaluate the fusion behavior of plain PEEK cages in comparison to titanium-coated PEEK (TiPEEK) cages.

Method We randomized 104 patients with single-level cervical radiculopathy or mild myelopathy. They were divided into two groups of 52 patients each, receiving either a PEEK cage or the titanium-coated variant of the same cage type. The 1- and 2-year follow-ups were completed by 43 patients in the PEEK group and by 50 patients in the TiPEEK group. Fusion was determined by plain X-ray and lateral functional X-ray.

Results Two years after surgery, a complete fusion was observed in 37 patients of the PEEK group (86%). Six cases were considered as nonunions. In the TiPEEK group, we found 41 fusions (82%) and 9 nonunions at this time. The difference was not considered significant (p = 0.59). The clinical evaluation of the two groups showed no difference in the neurologic examination as well in the pain scores over the time period.

Conclusions Despite some assumptions about an advantage of TiPEEK over PEEK cages for fusion in cervical spine surgery, this prospective randomized controlled study did not find an accelerated or improved fusion using TiPEEK for anterior cervical diskectomy.

Keywords

cervical disk herniation - cervical radiculopathy - cervical cages - cervical fusion

Author Contributions

J.S. was responsible for the statistical analysis, preparation of the manuscript, and performed most of the surgeries. T.K. was responsible for data gathering, patient follow-up, and surgeries. S.K. Bajaj was responsible for radiologic diagnosis. A.G. Hellwig was involved in patient recruiting and surgery. M.W. created the study design, organized ethics approval and funding, and performed surgeries.

Ethical Approval

Ethics approval was obtained from the medical ethical committee of the state medical association of Lower Saxony, Germany.

Informed Consent

Informed consent to participate and for publication was obtained from every patient prior to inclusion in the study.

Publication History

Received: 05 December 2022

Accepted: 09 January 2023

Article published online:
28 July 2023

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