Sequential Enzymolysis of Ligament and Resultant Stress-Strain Behavior

Abstract

Enzymolysis has been used as a technique to elucidate the contributions of the two structural proteins, collagen and elastin, and the matrix ground substance (“mucopolysaccharides”) to the mechanical response of ligamentum nuchae in vitro. Specimens cut from the same ligament were drawn to failure after being subjected to varying sequences of enzyme and/or buffer treatments. Collagenase, hyaluronidase + β-glucuronidase, trypsin, and elastase were employed. The data suggest that the collagen and elastic fiber networks are kept somewhat apart and lubricated by the mucopolysaccharide matrix and that the elastic fiber network constrains the collagen network from slipping viscoelastically at both low and high strain, which thus prevents greater alignment of the collagen fibers and, probably, irreversible changes in the dimensions and microstructure of the tissue under normal physiologic functioning.