title: Computational biomechanics to simulate the femoropopliteal intersection during knee flexion: a preliminary study.
abstract: OBJECTIVE
  To assess if finite element (FE) models can be used to predict deformation of the femoropopliteal segment during knee flexion.
  
  
  METHODS
  Magnetic resonance angiography (MRA) images were acquired on the lower limbs of 8 healthy volunteers (5 men; mean age 28 ± 4 years). Images were taken in 2 natural positions, with the lower limb fully extended and with the knee bent at ~ 40°. Patient-specific FE models were developed and used to simulate the experimental situation. The displacements of the artery during knee bending as predicted by the numerical model were compared to the corresponding positions measured on the MRA images.
  
  
  RESULTS
  The numerical predictions showed a good overall agreement between the calculated displacements of the motion measures from MRA images. The average position error comparing the calculated vs. actual displacements of the femoropopliteal intersection measured on the MRA was 8 ± 4 mm. Two of the 8 subjects showed large prediction errors (average 13 ± 5 mm); these 2 volunteers were the tallest subjects involved in the study and had a low body mass index (20.5 kg/m²).
  
  
  CONCLUSIONS
  The present computational model is able to capture the gross mechanical environment of the femoropopliteal intersection during knee bending and provide a better understanding of the complex biomechanical behavior. However, results suggest that patient-specific mechanical properties and detailed muscle modeling are required to provide accurate patient-specific numerical predictions of arterial displacement. Further adaptation of this model is expected to provide an improved ability to predict the multiaxial deformation of this arterial segment during leg movements and to optimize future stent designs.
authors.affiliation: Clinical and Interventional Angiology, Inselspital, University Hospital Bern, Switzerland. nicolas.diehm@insel.ch
authors.forename: Nicolas
authors.initials: N
authors.lastname: Diehm
authors.forename: Sangmun
authors.initials: S
authors.lastname: Sin
authors.forename: Hanno
authors.initials: H
authors.lastname: Hoppe
authors.forename: Iris
authors.initials: I
authors.lastname: Baumgartner
authors.forename: Philippe
authors.initials: P
authors.lastname: Büchler
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D001827:Body Height; D015992:Body Mass Index; D003198:Computer Simulation; D005260:Female; D005263:Femoral Artery / Q000033:anatomy & histology / Q000502:physiology*; D020342:Finite Element Analysis; D006801:Humans; D007717:Knee / Q000098:blood supply*; D018810:Magnetic Resonance Angiography; D008297:Male; D008955:Models, Cardiovascular; D009119:Muscle Contraction; D009716:Numerical Analysis, Computer-Assisted; D010865:Pilot Projects; D011150:Popliteal Artery / Q000033:anatomy & histology / Q000502:physiology*; D013314:Stress, Mechanical