STP1173: Characterization and Quantification of Fretting Particulates Generated in Ceramic/Metal and Metal/Metal Modular Head/Taper Systems

    Bhambri, SK
    Senior research engineer and group manager, Engineering Test Laboratory, Zimmer, Inc., Warsaw, IN

    Gilbertson, LN
    Senior research engineer and group manager, Engineering Test Laboratory, Zimmer, Inc., Warsaw, IN

    Pages: 16    Published: Jan 1994


    Abstract

    The use of modular head/Morse taper joints in total hip replacements has become a preferred surgical practice in consideration of the flexibility in surgical procedures and reduced inventory. The modular joints also offer an advantage in selection of appropriate material for components of a prosthesis depending upon the performance requirements. These modular joints have performed successfully in vivo for well over a decade. Recently, however, the release of fretting wear particulates from prosthetic implants in total hip arthroplasty has received greater attention, and a concern has been expressed for the modular head/taper joint to be a source of metal debris.

    In this paper, an experimental setup is described for conducting fretting/corrosion fatigue testing of modular head/taper assemblies in simulated body environments. The test setup consisted of a special cell designed to contain simulated body environment and to retain all particles greater than 0.20μm, generated due to fretting fatigue. For this purpose, in-line filters were used and the environmental chamber was made of acrylic material to avoid any contamination. The test environment was aerated Ringer's solution circulated in a closed loop at 37°C. The fatigue load was applied on the head in 15°C mediolateral anatomic orientation. The functional capabilities of this setup was demonstrated by testing alumina ceramic and cobalt-chromium-molyb-denum femoral heads fitted on titanium alloy tapers, at a fatigue load of 5.34 kN and a stress ratio of 0.1. The results are summarized in terms of characterization and quantification of any particulates generated, and surface topographical changes on both head and taper contact surfaces.

    Keywords:

    fatigue, fretting, Ringer's solution, wear, alumina, surface roughness, scanning electron microscope


    Paper ID: STP18098S

    Committee/Subcommittee: F04.13

    DOI: 10.1520/STP18098S


    CrossRef ASTM International is a member of CrossRef.