Evaluating Osseointegration Into a Deeply Porous Titanium Scaffold: A Biomechanical Comparison With PEEK and Allograft
- PMID: 27135643
- DOI: 10.1097/BRS.0000000000001672
Evaluating Osseointegration Into a Deeply Porous Titanium Scaffold: A Biomechanical Comparison With PEEK and Allograft
Abstract
Study design: This was a biomechanical push-out testing study using a porcine model.
Objective: The purpose was to evaluate the strength of implant-bone interface of a porous titanium scaffold by comparing it to polyetheretherketone (PEEK) and allograft.
Summary of background data: Osseointegration is important for achieving maximal stability of spinal fusion implants and it is desirable to achieve as quickly as possible. Common PEEK interbody fusion implants appear to have limited osseointegration potential because of the formation of fibrous tissue along the implant-bone interface. Porous, three-dimensional titanium materials may be an option to enhance osseointegration.
Methods: Using the skulls of two swine, in the region of the os frontale, 16 identical holes (4 mm diameter) were drilled to 10 mm depth in each skull. Porous titanium, PEEK, and allograft pins were press fit into the holes. After 5 weeks, animals were euthanized and the skull sections with the implants were cut into sections with each pin centered within a section. Push-out testing was performed using an MTS machine with a push rate of 6 mm/min. Load-deformation curves were used to compute the extrinsic material properties of the bone samples. Maximum force (N) and shear strength (MPa) were extracted from the output to record the bonding strength between the implant and surrounding bone. When calculating shear strength, maximum force was normalized by the actual implant surface area in contact with surrounding bone.
Results: Mean push-out shear strength was significantly greater in the porous titanium scaffold group than in the PEEK or allograft groups (10.2 vs. 1.5 vs. 3.1 MPa, respectively; P < 0.05).
Conclusion: The push-out strength was significantly greater for the implants with porous titanium coating compared with the PEEK or allograft. These results suggest that the material has promise for facilitating osseointegration for implants, including interbody devices for spinal fusion.
Level of evidence: N/A.
References
-
- Vadapalli S, Sairyo K, Goel VK, et al. Biomechanical rationale for using polyetheretherketone (PEEK) spacers for lumbar interbody fusion-a finite element study. Spine 2006; 31:E992–E998.
-
- Kersten RF, Van Gaalen SM, De Gast A, et al. Polyetheretherketone (PEEK) cages in cervical applications: a systematic review. Spine J 2015; 15:1446–1460.
-
- Lied B, Roenning PA, Sundseth J, et al. Anterior cervical discectomy with fusion in patients with cervical disc degeneration: a prospective outcome study of 258 patients (181 fused with autologous bone graft and 77 fused with a peek cage). BMC Surg 2010; 10:10.
-
- Rousseau MA, Lazennec JY, Saillant G. Circumferential arthrodesis using PEEK cages at the lumbar spine. J Spinal Disord Tech 2007; 20:278–281.
-
- Kurtz SM, Devine JN. PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials 2007; 28:4845–4869.
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