Carbon fiber reinforced PEEK Optima-A composite material biomechanical properties and wear/debris characteristics of CF-PEEK composites for orthopedic trauma implants

Background: The advantageous properties of carbon fiber reinforced polyetheretherketone (CF-PEEK) composites for use as orthopedic implants include similar modulus to bone and ability to withstand prolonged fatigue strain. Methods: The CF-PEEK tibial nail, dynamic compression plate, proximal humeral plate and distal radius volar plate were compared biomechanically (by four-point bending, static torsion of the nail, and bending fatigue) and for wear/debris (by amount of the debris generated at the connection between the CF-PEEK plate and titanium alloy screws) to commercially available devices. Results: Four-point bending stress of the tibial nail and dynamic and distal radius plates yielded characteristics similar to other commercially available devices. The distal volar plate bending structural stiffness of the CF-PEEK distal volar plate was 0.542 Nm² versus 0.376 Nm² for the DePuy's DVR anatomic volar plate. The PHILOS proximal humeral internal locking system stainless steel plate was much stronger (6.48 Nm²) than the CF-PEEK proximal humeral plate (1.1 Nm²). Tibial nail static torsion testing showed similar properties to other tested nails (Fixion, Zimmer and Synthes). All tested CF-PEEK devices underwent one million fatigue cycles without failure. Wear test showed a lower volume of generated particles in comparison to the common implants in use today. Interpretation: Thus, these tested implants were similar to commercially used devices and can be recommended for use as implants in orthopedic surgery.