Effects of Aponeurosis and Fiber Alignment on The Force and Stability During Isometric Contraction of Frog Gastrocnemius

The aim of this study is to analyze the contractile behavior of frog gastrocnemius muscle (also
known as plantaris longus) via a computational model based on the finite element method (FEM).
Therefore, a physical reality simulation scenario which is based on the finite element method has been
generated. The finite element model developed within the scenario uses the theory of distributed-
moments in order to study the effect of the angular alignment of the aponeurosis sheet covering the
muscle on the total contractile force. By the way, in order to investigate the effect of fiber alignment,
fibers have been typified two distinct fiber architectures, as the uniaxial and fusiform ones and the effect
of different architecture type on the developed force and convergence was studied. The physical reality
simulation outputs have been compared with the real frog muscle force responses that has been obtained
in the laboratory condition. Results indicate that both the choice of fiber architecture as well as the
aponeurosis alignment and position have important consequences in terms of the computed muscle force
as well was the numerical stability of the model and the muscle model used in this work is compatible to
use for three-dimensional muscle modelling.