TITLE:
On a Constitutive Material Model to Capture Time Dependent Behavior of Cortical Bone
AUTHORS:
Anders Halldin, Mats Ander, Magnus Jacobsson, Stig Hansson
KEYWORDS:
Cortical bone Viscoelastic-Viscoplastic Creep Remodeling Constitutive Model
JOURNAL NAME:
World Journal of Mechanics,
Vol.4 No.11,
November
28,
2014
ABSTRACT: It is
commonly known that cortical bone exhibits viscoelastic-viscoplastic behavior
which affects the biomechanical response when an implant is subjected to an
external load. In addition, long term effects such as creep, relaxation and
remodeling affect the success of the implant over time. Constitutive material
models are commonly derived from data obtained in in vitro experiments. However during function, remodeling of bone
greatly affects the bone material over time. Hence it is essential to include
long term in vivo effects in a
constitutive model of bone. This paper proposes a constitutive material model
for cortical bone incorporating viscoelasticity, viscoplasticity, creep and
remodeling to predict stress-strain at various strain rates as well as the
behavior of bone over time in vivo.
The rheological model and its parameters explain the behavior of bone subjected
to longitudinal loading. By a proper set of model parameters, for a specific
cortical bone, the present model can be used for prediction of the behavior of
this bone under specific loading conditions. In addition simulation with the
proposed model demonstrates excellent agreement to in vitro and in vivo experimental results in the literature.