Suitability of carbon fiber–reinforced polyetheretherketone cages for use as anterior struts following corpectomy

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>Fibular allograft remains a widely used strut for corpectomy surgeries. The amount of graft material that can be packed into an allograft strut has not been quantified. Cages are an alternative to fibular allograft for fusion surgeries. The authors of this study assessed the suitability of carbon fiber–reinforced polyetheretherketone (CFRP) cages for anterior corpectomy surgeries. They further explored the parameters known to affect fusion rates in clinical practice.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>Six fibular allografts were tested at standard lengths. Three sets of carbon fiber cages (Bengal, DePuy Spine), each with a different footprint size but the same lengths, were tested. The allografts and cages were wrapped in adhesive, fluid-tight transparent barriers and filled with oil. The volume and weight of the oil instilled as well as the implant footprints were measured. The fibular allografts and cages were tested at 20-, 40-, and 50-mm lengths. Two investigators independently performed all measurements 5 times. Five CFRP cubes (1 × 1 × 1 cm) were tested under pure compression, and load versus displacement curves were plotted to determine the modulus of elasticity.</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>Significantly more oil fit in the CFRP cages than in the fibular allografts (p &lt; 0.0001). The weight and volume of oil was 4–6 times greater in the cages. Interobserver (r = 0.991) and intraobserver (r = 0.993) reliability was excellent. The modulus of elasticity for CFRP was 16.44 ± 2.07 GPa.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>Carbon fiber–reinforced polyetheretherketone cages can accommodate much more graft material than can fibular allografts. In clinical practice, the ability to deliver greater amounts of graft material following a corpectomy may improve fusion rates.</jats:p></jats:sec>

Polyetheretherketone and Its Composites for Bone Replacement and Regeneration

“…As mentioned, the modulus of elasticity of pure PEEK is 3.7-4.0 GPa [27,28], being lower than that of human cortical bone ranging from 7 to 30 GPa [9]. Therefore, many efforts have been spent by the researchers in enhancing the stiffness and strength of PEEK by reinforcing with HA microparticles, HA whiskers and carbon fibers for load-bearing orthopedic applications [39][40][41][42][43][44][45][46][47][131][132][133][134][135][136][137][138]. The elastic modulus of HA is 120.6 GPa [26], so it can be used as a reinforcement to stiffen PEEK.…”

“…PEEK-carbon fiber (CF) composites have been explored for orthopedic applications in posterior lumbar interbody fusion implants, screws, intramedullary nails, acetabular cups and dental implants [43][44][45][46][47][136][137][138][139][140][141][142][143]. Pure PEEK is inadequate for those applications because of insufficient stiffness.…”

“…To enhance the stiffness and mechanical strength of PEEK, continuous and discontinuous carbon fibers (CFs) with high elastic modulus were added to PEEK accordingly [42]. The PEEK/CF composites have been used for lumbar interbody fusion cages, acetabular cup of hip prostheses, and dental implants/abutments [43][44][45][46][47].…”

In vivo analysis of covering materials composed of biodegradable polymers enriched with flax fibers

“…It could be proven that some natural fibers prevent stress shielding and increase bone remodeling [16, 17]. Furthermore, many studies have shown that flax fibers have better mechanical properties, similar to glass fibers, and lower water absorption, in comparison with other natural fibers [18–20].…”

“…Furthermore, many studies have shown that flax fibers have better mechanical properties, similar to glass fibers, and lower water absorption, in comparison with other natural fibers [18–20]. Recently, a hybrid natural fiber polymer composite material based on epoxy resin, enriched with sisal, jute and hemp fibers, was proposed for clinical application as orthopedic implants for femur bone prosthesis because of its good material properties, such as low density, increased tensile, compression, bending strength, and the mechanical behavior comparable to that of long human bones [17, 21]. In recent years, a new generation of transgenic plants was increasingly developed for the production of recombinant medicines and industrial products, such as vaccines, antibodies, biofuels and plastics [22–25].…”