title: Influence of the fixation region of a press-fit hip endoprosthesis on the stress-strain state of the "bone-implant" system.
abstract: Although significant progress has been made in the development of total hip replacement, behaviour of the femoral component of an endoprosthesis in relation to the type of its fixation in the bone is still not fully understood. In this paper, behaviour of the femoral bone and the stem prosthesis is studied taking into account different types of prosthesis fixation in the medullary canal of the femur under the action of functional loads. For an analysis, a three-dimensional model of a femur has been developed based on the results of a computed tomography. The stress-strain state governing behaviour of the femoral bone and the stem prosthesis has been estimated with the use of the finite element method (FEM). The FEM analysis has shown that for the diaphyseal fixation, the area of contact between the surface of the endoprosthesis and the bone is insufficient and leads to large stresses in the implant accompanied by stress concentration in the distal femur. An increase in the area of contact between the implant and the bone raises the stiffness of the "bone-implant" system, which, in turn, reduces stresses in the implant. The applied metaphyseal-type fixation yielded an improvement of results regarding behaviour of the femoral bone and the stem prosthesis. Namely, the study yielded the distribution of stress in the bone similar to the physiological stress state.
authors.affiliation: Lodz University of Technology, Department of Automation, Biomechanics and Mechatronics, 1/15 Stefanowski Str., 90-924 Lodz, Poland.
authors.forename: Ievgen
authors.initials: I
authors.lastname: Levadnyi
authors.affiliation: Lodz University of Technology, Department of Automation, Biomechanics and Mechatronics, 1/15 Stefanowski Str., 90-924 Lodz, Poland; Warsaw University of Technology, Institute of Vehicles, 84 Narbutta Str., 02-524 Warsaw, Poland. Electronic address: jan.awrejcewicz@p.lodz.pl.
authors.forename: Jan
authors.initials: J
authors.lastname: Awrejcewicz
authors.affiliation: Lodz University of Technology, Department of Automation, Biomechanics and Mechatronics, 1/15 Stefanowski Str., 90-924 Lodz, Poland.
authors.forename: Márcio Fagundes
authors.initials: MF
authors.lastname: Goethel
authors.affiliation: Dnipropetrovsk State Medical Academy, 9 Dzerzhenskiy Str., Dnipropetrovsk, Ukraine.
authors.forename: Alexander
authors.initials: A
authors.lastname: Loskutov
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation*; D001696:Biomechanical Phenomena / Q000502:physiology; D019544:Equipment Failure Analysis / Q000379:methods*; D005264:Femoral Fractures / Q000000981:diagnostic imaging; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery; D020342:Finite Element Analysis; D006622:Hip Prosthesis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008954:Models, Biological; D011474:Prosthesis Design; D011475:Prosthesis Failure; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed
keywords: Femur; Finite elements analysis; Micromotion; Stress–strain state; Total hip replacement