title: Evaluation of taper joints with combined fatigue and crevice corrosion testing: comparison to human explanted modular prostheses.
abstract: The requirement for revision surgery of total joint replacements is increasing and modular joint replacement implants have been developed to provide adjustable prosthetic revision systems with improved intra-operative flexibility. An electrochemical study of the corrosion resistance of the interface between the distal and proximal modules of a modular prosthesis was performed in combination with a cyclic fatigue test. The complexity resides in the existence of interfaces between the distal part, the proximal part, and the dynamometric screw. A new technique for evaluating the resistance to cyclic dynamic corrosion with crevice stimulation was used and the method is presented. In addition, two components of the proximal module of explanted Ti6Al4V and Ti6Al7Nb prostheses were investigated by optical and electron microscopy. Our results reveal that: The electrolyte penetrates into the interface between the distal and proximal modules during cyclic dynamic fatigue tests, the distal module undergoes cracking and corrosion was generated at the interface between the two models; The comparison of the explanted proximal parts with the similar prostheses evaluated following cyclic dynamic crevice corrosion testing showed that there were significant similarities indicating that this method is suitable for evaluating materials used in the fabrication of modular prostheses.
authors.affiliation: PX Group S.A., Dep R&D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds, Switzerland. Electronic address: lucien.reclaru@pxgroup.com.
authors.forename: L
authors.initials: L
authors.lastname: Reclaru
authors.forename: R A
authors.initials: RA
authors.lastname: Brooks
authors.forename: M
authors.initials: M
authors.lastname: Zuberbühler
authors.forename: P-Y
authors.initials: PY
authors.lastname: Eschler
authors.forename: F
authors.initials: F
authors.lastname: Constantin
authors.forename: G
authors.initials: G
authors.lastname: Tomoaia
mesh_terms: D000497:Alloys; D002412:Cations; D003343:Corrosion; D004560:Electricity; D055664:Electrochemical Techniques; D006801:Humans; D008422:Materials Testing; D019736:Prostheses and Implants; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D002412:Cations; C070282:Ti-6Al-7Nb alloy; C031462:titanium alloy (TiAl6V4); D014025:Titanium
keywords: Explanted prosthesis; Fatigue corrosion; Modular prosthesis