title: Effects of liner stiffness for trans-tibial prosthesis: a finite element contact model.
abstract: The socket liner plays a crucial role in redistribution of the interface stresses between the stump and the socket, so that the peak interface stress could be reduced. However, how the peak stress is affected by various liner stiffnesses is still unknown, especially when the phenomenon of the stump slide within the socket is considered. This study employed nonlinear contact finite element analyses to study the biomechanical reaction of the stump sliding with particular attention to the liner stiffness effects of the trans-tibial prosthesis. To validate the finite element outcomes, experimental measurements of the interface stresses and sliding distance were further executed. The results showed that the biomechanical response of the stump sliding are highly nonlinear. With a less stiff liner, the slide distance of the stump would increase with a larger contact area. However, this increase in the contact area would not ensure a reduction in the peak interface stress and this is due to the combined effects of the non-uniform shape of the socket and the various sliding distances generated by the different liner stiffnesses.
authors.affiliation: Institute of Biomedical Engineering, National Cheng Kung University, 1, University Road, Tainan 701, Taiwan.
authors.forename: Chih-Chieh
authors.initials: CC
authors.lastname: Lin
authors.forename: Chih-Han
authors.initials: CH
authors.lastname: Chang
authors.forename: Chu-Lung
authors.initials: CL
authors.lastname: Wu
authors.forename: Kao-Chi
authors.initials: KC
authors.lastname: Chung
authors.forename: I-Chen
authors.initials: IC
authors.lastname: Liao
mesh_terms: D000671:Amputation, Surgical; D000672:Amputation Stumps / Q000000981:diagnostic imaging / Q000503:physiopathology*; D000674:Amputees / Q000534:rehabilitation; D001672:Biocompatible Materials / Q000737:chemistry; D003198:Computer Simulation; D017076:Computer-Aided Design; D019544:Equipment Failure Analysis / Q000379:methods*; D020342:Finite Element Analysis; D017276:Friction; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D007720:Knee Prosthesis; D008422:Materials Testing; D008954:Models, Biological; D011312:Pressure; D011474:Prosthesis Design / Q000379:methods*; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013499:Surface Properties; D013977:Tibia / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D016474:Weight-Bearing
chemical_list: D001672:Biocompatible Materials