1.1 These This guide covers the evaluation of modular head and/or neck systems on femoral stems used in Total Hip Arthroplasty to fretting corrosion under cyclic fatigue forces in simulated corrosive environments.. 1.2 The guide is intended to accelerate the fretting corrosion effect to make it possible to evaluate the resistance of new modular head and/or neck systems to fretting/corrosion prior to clinical use. As the technique is in development, it may not be suitable for evaluation of modular taper systems for other devices.
4.1 This test practice can be used to rank the effects of head and cone materials, design variables, manufacturing, and other conditions on the resistance to fretting corrosion under cyclic forces in a simulated human body environment. 4.2 These test methods must use the modular femoral components that meet the full requirements of the modular components of actual femoral prostheses. The materials and processing must be the same as the final finished products with the exception of sterilization. 4.3 The test may reveal features of materials, material combinations, designs, and manufacturing processes that work to inhibit the occurrence of crevice corrosion. 4.4 In the fatigue test methods, it is recognized that actual loading in vivo is quite varied, and that no one set of experimental conditions can encompass all possible variations. Thus, the test methods included here represent a simplified model for the purposes of comparisons between designs and materials. 4.5 The environment is representative of the saline environment for the femoral prosthesis in the human body with the exception that the reactivity of the environment is accelerated by increasing the temperature higher than the normal temperature of the human body and using acid to decrease the pH of the environment to accelerate the decrease in pH than can occur in crevices with metallic surfaces
KeywordsFatigue; Fretting; Fretting Corrosion; Hip; Modular; Taper; Neck; Adapter; Sleeve
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top