Tribology And Testing Of Orthopedic Implants

By Aia Malik, Lucideon, and Chris Pickles, Ph.D.

The orthopedic implant industry is in a continual state of development, witnessing an explosion of novel materials, designs, and applications. This process is, however, often laced with challenges and articulating joints can present the greatest number of these. The biocompatibility of an orthopedic implant is essential but, as an increased number of patients outlive the life expectancy of their implant; longevity is becoming a significant clinical problem. Thus, the bio-tribological performance of an implant becomes increasingly relevant.

Bio-tribology is the study of friction, lubrication and wear as they occur in the human body and, as such, are all important factors to consider in the design of implants. Assessment of an implant covers three areas - mechanical testing, debris analysis and surface analysis. In this paper we will review the key techniques available, focusing on the value of generating a complete picture and an understanding of an orthopedic implant in terms of how the design, base material or coating behaves under friction and loading.