title: Parametric elastic analysis of coupled helical coils for tubular implant applications: experimental characterization and numerical analysis.
abstract: Coupled helical coils show promising mechanical behavior to be used as tubular organ constructs, e.g., in trachea or urethra. They are potentially easy to manufacture by filament winding of biocompatible and resorbable polymers, and could be tailored for suitable mechanical properties. In this study, coupled helical coils were manufactured by filament winding of melt-extruded polycaprolactone, which was reported to demonstrate desired in vivo degradation speed matching tissue regeneration rate. The tensile and bending stiffness was characterized for a set of couple helical coils with different geometric designs, with right-handed and left-handed polymer helices fused together in joints where the filaments cross. The Young's modulus of unidirectional polycaprolactone filaments was characterized, and used as input together with the structural parameters of the coupled coils in finite element simulations of tensile loading and three-point bending of the coils. A favorable comparison of the numerical and experimental results was found, which paves way for use of the proposed numerical approach in stiffness design under reversible elastic conditions of filament wound tubular constructs.
authors.affiliation: Division of Applied Mechanics, Department of Engineering Sciences, Uppsala University, Box 534, SE-751 21 Uppsala, Sweden.
authors.forename: Jinxing
authors.initials: J
authors.lastname: Huo
authors.forename: Ramiro
authors.initials: R
authors.lastname: Rojas
authors.forename: Jan
authors.initials: J
authors.lastname: Bohlin
authors.forename: Jöns
authors.initials: J
authors.lastname: Hilborn
authors.forename: E Kristofer
authors.initials: EK
authors.lastname: Gamstedt
mesh_terms: D004548:Elasticity; D020342:Finite Element Analysis; D008422:Materials Testing; D011091:Polyesters; D019736:Prostheses and Implants
chemical_list: D011091:Polyesters; C016240:polycaprolactone
keywords: Coupled helical coils; Finite element simulation; Structural stiffness; Tubular implants