Contribution of Glycosaminoglycans to Viscoelastic Tensile Behavior of Human Ligament

Trevor J. Lujan, Clayton J. Underwood, Nathan T. Jacobs, Jeffrey A. Weiss

Research output: Contribution to journalArticlepeer-review

119 Scopus citations

Abstract

The viscoelastic properties of human ligament potentially guard against structural failure, yet the microstructural origins of these transient behaviors are unknown. Glycosaminoglycans (GAGs) are widely suspected to affect ligament viscoelasticity by forming molecular bridges between neighboring collagen fibrils. This study investigated whether GAGs directly affect viscoelastic material behavior in human medial collateral ligament (MCL) by using nondestructive tensile tests before and after degradation of GAGs with chondroitinase ABC (ChABC). Control and ChABC treatment (83% GAG removal) produced similar alterations to ligament viscoelasticity. This finding was consistent at different levels of collagen fiber stretch and tissue hydration. On average, stress relaxation increased after incubation by 2.2% (control) and 2.1% (ChABC), dynamic modulus increased after incubation by 3.6% (control) and 3.8% (ChABC), and phase shift increased after incubation by 8.5% (control) and 8.4% (ChABC). The changes in viscoelastic behavior after treatment were significantly more pronounced at lower clamp-to-clamp strain levels. A 10% difference in the water content of tested specimens had minor influence on ligament viscoelastic properties. The major finding of this study is that mechanical interactions between collagen fibrils and GAGs are unrelated to tissue-level viscoelastic mechanics in mature human MCL. These findings narrow the possible number of extracellular matrix molecules that have a direct contribution to ligament viscoelasticity.
Original languageAmerican English
JournalJournal of Applied Physiology
Volume106
Issue number2
DOIs
StatePublished - Feb 2009
Externally publishedYes

Keywords

  • decorin
  • dermatan sulfate
  • material properties
  • polyethylene glycol
  • tendon

EGS Disciplines

  • Biomedical Engineering and Bioengineering
  • Mechanical Engineering

Fingerprint

Dive into the research topics of 'Contribution of Glycosaminoglycans to Viscoelastic Tensile Behavior of Human Ligament'. Together they form a unique fingerprint.

Cite this