Mechanical characterization and constitutive modelling of the damage process in rectus sheath

• Type: Article in International Scientific Journal
• Date: 2012

Authors

martins, p (Author) FEUP; pena, e (Author) Other; jorge, rmn (Author) FEUP; santos, a (Author) Other; santos, l (Author) Other; mascarenhas, t (Author) FMUP; calvo, b (Author) Other

Journal

Title: Journal of the Mechanical Behavior of Biomedical Materials

Vol. 8

Pages: 111-122

ISSN: 1751-6161

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 48 Citations

Scopus - 51 Citations

Scientific classification

FOS: Engineering and technology > Environmental biotechnology

Other information

Authenticus ID: P-002-BJ2

DOI: 10.1016/j.jmbbm.2011.12.005

Abstract (EN): The aim of this study is to characterize and model the damage process in the anterior rectus abdominal aponeurosis (anterior rectus sheath) undergoing finite deformations. The resistance of the anterolateral abdominal aponeuroses is important when planning the surgical repair of incisional hernias, among other medical procedures. Previous experiments in prolapsed vaginal tissue revealed that a softening process occurs before tissue rupture. This nonlinear damage behaviour requires a continuum damage theory commonly used to describe the softening behaviour of soft tissues under large deformations. The structural model presented here was built within the framework of non-linear continuum mechanics. Tissue damage was simulated considering different damage behaviours for the matrix and the collagen fibres. The model parameters were fit to the experimental data obtained from anterior rectus sheath samples undergoing finite deformations in uniaxial tension tests. The tests were carried out with samples cut along the direction of the collagen fibres, and transversal to the fibres. Longitudinal and transverse mechanical properties of human anterior rectus sheath are significantly different. The damage model was able to predict the stress-strain behaviour and the damage process accurately. The error estimations pointed to an excellent agreement between experimental results and model fittings. For all the fitted data, the normalized RMS error epsilon presented very low values and the coefficient of determination R-2 was close to 1. The present work constitutes the first attempt (as far as the authors know) to present a damage model for the human rectus sheath.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12