Wear properties of poly‐ether‐ether‐ketone bearing combinations under zero and cross shear kinematics in total knee arthroplasty

Abstract

Poly-ether-ether-ketone (PEEK), having shown favorable biocompatibility in spinal applications is being considered as an alternative biomaterial in orthopaedics, either as part of an all-polymer bearing couple, or a replacement for the metallic component in hard-on-soft bearings. Throughout the literature ultra-high molecular weight polyethylene exhibits a range of wear behavior dependent upon the amount of cross shear (CS) present in the bearing motion; in comparison, the behavior of PEEK bearing combinations subject to cross shear conditions is less understood. The aim of this study was to investigate the effect of cross shear on PEEK-on-PEEK and PEEK-on-Metal bearing couples. Wear tests were conducted using a four station pin-on-plate rig capable of uni-directional motion (zero cross shear) and multidirectional motion (cross shear); reciprocation (1 Hz), rotation (0 or 1 Hz), with gravimetric wear analysis used to determine the wear factors. The combined wear factors from the PEEK pins articulating on either PEEK or metal plates in this study suggest that it is preferable to use PEEK-on-Metal bearing couples under zero cross shear kinematic conditions and PEEK-on-PEEK for high cross shear applications. PEEK appears to demonstrate a CS dependency when articulating on hard surfaces. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.

Mechanical failure of distal femur mega prosthesis due to polyaryl-ether-ether-ketone (PEEK) hinge component

“…PEEK is lightweight and easy to manufacture, and its ability to withstand chemical and radiation damage, as well as its reduced distortion on three-dimensional imaging, has led to numerous studies exploring its potential as a substrate for orthopedic load-bearing implants [ 14 ]. While it has shown promise in studies focusing on its use in fracture fixation plates in orthopedic trauma [ 15 – 17 ], reports of PEEK’s failure as an articulating component against metallic counter face are gradually emerging [ 18 , 19 ]. PEEK’s reduced structural stiffness may lead to reduced interface stresses, eventually resulting in deformation and instability of knee arthroplasty prostheses, as described by Abdullah et al for PEEK femoral components [ 20 , 21 ].…”