ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

MULTISCALE COMPUTATIONAL MODELING OF A NEW
SCAFFOLD FOR ANTERIOR CRUCIATE LIGAMENT TISSUE
ENGINEERING
ABSTRACT
C. P. Laurent 1 , D. Durville 2 , R. Rahouadj 1 and J.-F. Ganghoffer 1
Tissue engineering has the potential to overcome the limitations associated with current
reconstructions strategies of the Anterior Cruciate Ligament (ACL). A new scaffold
based on copoly(lactic acid-co-(ε-caprolactone)) (PLCL) fibers arranged into a
multilayer braided structure has been recently proposed. Thanks to its predictable and
tailorable architecture, this scaffold is particularly adapted to numerical modeling. The
objective of the present study is to propose a Finite Element (FE) modeling of this
scaffold using a recent FE code dedicated to textile materials, in view of (1) predicting
and optimizing the tensile properties of the scaffold at the articular (macroscopic) scale
(2) determining the variations of the mechanical micro-environment at the cellular
(microscopic) scale induced by the cyclic stretching of the scaffold. The dedicated FE
approach particularly focuses on the detection and modeling of the contact/friction
interactions between fibers within a large deformation framework. The FE simulations
allow both the unknown initial braided configuration and the tensile responses of the
scaffold to be computed. Comparisons between computed and actual geometries and
between simulated and experimental tensile responses have validated the approach. As a
result, the present simulations allow a relevant candidate for ACL repair to be proposed.
Moreover, it allows the mechanical micro-environment at the cellular scale to be
quantified throughout the stretching of the scaffold that may be induced by the in vitro
dynamic culture of the scaffold or by the in vivo loading after its implantation.
1. INTRODUCTION
Tissue engineering offers promising alternatives to current Anterior Cruciate
Ligament (ACL) reconstructions strategies, by potentially overcoming the limitations
associated with the gold standard autograft-based repair. Tissue engineering is based on
the seeding of reparative cells into a biodegradable scaffold which must match
biochemical, biomechanical and morphological requirements in order to allow
immediate stabilization of the knee as well as tissue ingrowth [1]. An ideal scaffold
should match two interrelated types of requirements (1) it must provide the cells with a
suited microenvironment (2) it must fulfill the physiological function of the native tissue
during the rehabilitation period. The design of optimal scaffold for a specific tissue
engineering application has consequently always been a crucial challenge for tissue
engineering scientists.
1
LEMTA, Group of Bioengineering, Nancy-Université, CNRS UMR 7563, 2 avenue Forêt de Haye,
54504 Vandœuvre-lès-Nancy, France
2
LMSSMat, CNRS UMR8579 - Ecole Centrale Paris, Grande Voie des Vignes, 92290 Chatenay-
Malabry, France