European Spine Journal

, Volume 26, Issue 3, pp 593–605 | Cite as

Radiological and clinical outcomes of novel Ti/PEEK combined spinal fusion cages: a systematic review and preclinical evaluation

  • Yusuf Assem
  • Ralph J. Mobbs
  • Matthew H. Pelletier
  • Kevin Phan
  • William R. Walsh
Review Article



The primary objective of this paper was to provide a systematic review of the available clinical studies of Ti/PEEK combined cages in spinal interbody fusion surgeries, focusing on their radiological and clinical outcomes. A secondary aim was to provide a review and evaluation of the in vitro and preclinical studies reported on Ti/PEEK-coated implants.


A systematic search of the literature was performed in March 2015 via three databases: Medline, Embase and Cochrane library. The following key search terms were combined with synonyms to identify relevant articles: “spinal fusion,” “PEEK,” “titanium” and “cage.”


The novelty of this intervention translates into a paucity of clinical trials, albeit the results of the seven clinical studies that met the criteria for inclusion are promising. All studies reported rate of fusion as a primary outcome. Two studies reported slightly improved fusion in the experimental Ti/PEEK combination cohort, one study identical fusion (91.7 %) and three studies excellent fusion (96, 100 and 94 %) in the Ti/PEEK cohort, although no differences reached statistical significance.


Clinical studies at this early stage demonstrate that Ti/PEEK implants are safe and efficacious, exhibiting similar fusion rates and clinical outcomes compared to the current standard PEEK. There is clinical evidence substantiating the improved radiographic fusion of Ti/PEEK, albeit the differences were not significant. This field is promising, gaining substantial popularity, and further clinical trials are needed in the future to establish Ti/PEEK cages as a mainstay of clinical practice.


Spinal fusion Cage Titanium PEEK Ti/PEEK 


Compliance with ethical standards

Conflict of interest


Supplementary material

586_2015_4353_MOESM1_ESM.docx (101 kb)
Supplementary material 1 (DOCX 100 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Yusuf Assem
    • 1
    • 2
    • 3
  • Ralph J. Mobbs
    • 3
    • 4
    • 5
  • Matthew H. Pelletier
    • 2
  • Kevin Phan
    • 3
    • 4
  • William R. Walsh
    • 2
  1. 1.Faculty of MedicineUniversity of New South WalesKensington, SydneyAustralia
  2. 2.Surgical and Orthopaedic Research Laboratory, Prince of Wales Clinical SchoolUNSWSydneyAustralia
  3. 3.Neurospine ClinicPrince of Wales Private HospitalRandwickAustralia
  4. 4.NeuroSpine Surgery Research Group (NSURG)SydneyAustralia
  5. 5.Department of Spine SurgeryPrince of Wales Private HospitalSydneyAustralia

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