Simulation of Fretting Wear at Orthopaedic Implant Interfaces

Abstract

Osteolysis due to wear debris is a primary cause of failure of total joint replacements. Although debris produced by the joint articulating surfaces has been studied and simulated extensively, fretting wear debris, produced at nonarticulating surfaces, has not received adequate attention. We developed a three-station fretting wear simulator to reproduce in vivo motion and stresses at the interfaces of total joint replacements. The simulator is based on the beam bending theory and is capable of producing cyclic displacement from 3 to 1000 microns, under varying magnitudes of contact stresses. The simulator offers three potential advantages over previous studies: The ability to control the displacement by load, the ability to produce very small displacements, and dynamic normal loads as opposed to static. A pilot study was designed to test the functionality of the simulator, and verify that calculated displacements and loads produced the predicted differences between two commonly used porous ingrowth titanium alloy surfaces fretting against cortical bone. After 1.5 million cycles, the simulator functioned as designed, producing greater wear of bone against the rougher plasma-sprayed surface compared to the fiber-mesh surface, as predicted. A novel pin-on-disk apparatus for simulating fretting wear at orthopaedic implant interfaces due to micromotion is introduced. The test parameters measured with the fretting wear simulator were as predicted by design calculations, and were sufficient to measure differences in the height and weight of cortical bone pins rubbing against two porous ingrowth surfaces, plasma-sprayed titanium and titanium fiber mesh.

Surface deterioration and elemental composition of retrieved orthodontic miniscrews

“…[26][27][28] In contrast, pure titanium is highly resistant to corrosion in any in-vivo environment likely to be encountered; however, its low strength limits its use as an implant.…”

Material and surface factors influencing backside fretting wear in total knee replacement tibial components

“…Linear motion was produced using the deformation of the three vertical rods under bending ( Fig. 1; Ebramzadeh et al, 2005). A four-bar linkage generated rotational micromotion (Fig.…”

Anisotropic Wear Resistance of Human Mandible Cortical Bone

“…So, the fretting wear occurs on the implant-cortical bone interface [10]. The wear occurred on the interface have attracted some attentions [11][12][13]. Some works have been carried out in our previous researches [10,14].…”