title: Design, analysis and verification of a knee joint oncological prosthesis finite element model.
abstract: BACKGROUND
  The aim of this paper was to design a finite element model for a hinged PROSPON oncological knee endoprosthesis and to verify the model by comparison with ankle flexion angle using knee-bending experimental data obtained previously.
  
  
  METHODS
  Visible Human Project CT scans were used to create a general lower extremity bones model and to compose a 3D CAD knee joint model to which muscles and ligaments were added. Into the assembly the designed finite element PROSPON prosthesis model was integrated and an analysis focused on the PEEK-OPTIMA hinge pin bushing stress state was carried out. To confirm the stress state analysis results, contact pressure was investigated. The analysis was performed in the knee-bending position within 15.4-69.4° hip joint flexion range.
  
  
  RESULTS
  The results showed that the maximum stress achieved during the analysis (46.6 MPa) did not exceed the yield strength of the material (90 MPa); the condition of plastic stability was therefore met. The stress state analysis results were confirmed by the distribution of contact pressure during knee-bending.
  
  
  CONCLUSIONS
  The applicability of our designed finite element model for the real implant behaviour prediction was proven on the basis of good correlation of the analytical and experimental ankle flexion angle data.
authors.affiliation: Department of Mechanics, Biomechanics and Mechatronics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technická 4, 166 07 Praha 6, Czech Republic.
authors.forename: Lukáš
authors.initials: L
authors.lastname: Zach
authors.affiliation: Department of Materials Forming, Faculty of Metallurgy and Materials Engineering, VŠB-TU Ostrava, 17. listopadu 15, Ostrava-Poruba 70833, Czech Republic; Regional Materials Science and Technology Centre, VŠB-TU Ostrava, 17. listopadu 15, Ostrava-Poruba 70833, Czech Republic. Electronic address: lenka.kuncicka@vsb.cz.
authors.forename: Lenka
authors.initials: L
authors.lastname: Kunčická
authors.affiliation: Department of Mechanics, Biomechanics and Mechatronics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technická 4, 166 07 Praha 6, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Růžička
authors.affiliation: Department of Materials Forming, Faculty of Metallurgy and Materials Engineering, VŠB-TU Ostrava, 17. listopadu 15, Ostrava-Poruba 70833, Czech Republic; Regional Materials Science and Technology Centre, VŠB-TU Ostrava, 17. listopadu 15, Ostrava-Poruba 70833, Czech Republic.
authors.forename: Radim
authors.initials: R
authors.lastname: Kocich
mesh_terms: D000465:Algorithms; D001859:Bone Neoplasms / Q000503:physiopathology* / Q000601:surgery*; D019245:Compressive Strength; D003198:Computer Simulation; D017076:Computer-Aided Design; D055119:Elastic Modulus; D019544:Equipment Failure Analysis; D020342:Finite Element Analysis; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D007720:Knee Prosthesis; D008954:Models, Biological; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000503:physiopathology*; D011474:Prosthesis Design; D017755:Prosthesis Fitting / Q000379:methods; D012984:Software; D013314:Stress, Mechanical; D013710:Tendons / Q000503:physiopathology*; D013718:Tensile Strength
keywords: Endoprosthesis; Finite element method; Finite element model; Knee joint; Knee-bending; Oncological implant