A Structural and Microstructural Model for Tendon and Ligament Stress-Stretch Response

Abstract

Abstract Collagen structural and microstructural organization are thought to contribute strongly to mechanical behavior in normal and healing tendon and ligament. Recent studies have attempted to correlate various collagen microstructural and structural features to material stiffness of healing ligaments (Frank et al., 1991, 1992; Padgett and Dahners 1992; Shrive et al., 1995). Other studies have suggested that progressive fiber failure may be a mechanism for damage accumulation and eventual failure of tendons and ligaments (Kennedy et al., 1976; Viidik 1978; Butler et al., 1984). It may also be an explanation for the observed permanent deformation of tendon at relatively low levels of strain (2–4%, Rigby et al., 1959; Abrahams 1967). Structural mathematical models for tendons and ligaments have been developed but few have incorporated more than one structural scale (i.e. fibril as well as fiber organization). The aim of this study is to develop a mathematical model for tendons and ligaments that will help to better understand the relationship between collagen structure, microstructure, and mechanical properties.