Shear and bulk creep compliances of human articular cartilage are evaluated from independent creep tests in torsion and uniaxial strain. Linearity of the compliance coefficients in the loading range tested indicates that the results are applicable to viscoelastic analyses of synovial joint mechanics. The measured compliances for normal and degenerative tissue are compared and found to differ significantly. Preliminary investigations also suggest that flow processes are not important in the initial stages of the deformation of normal tissue.
Keywords:
elasticity; viscoelasticity; synovial joint mechanics; shear modulus; bulk modulus; creep tests; degenerative cartilage