... saturation. The ligaments were considered as anisotropic hyperelastic and reinforced by a fibrillar collagen network. A compressive creep load of ¾ body weight was applied in full extension of the right knee during 200 s standing. Four finite element models were developed to simulate different meniscectomies...

... ligaments to cyclic (fatigue) and static (creep) loading. A gap injury was created in the midsubstance of both hindlimb medial collateral ligaments of 40 female 1-year-old New Zealand White rabbits. After a 14-week healing interval, medial collateral ligament gap scars were exposed to long-term fatigue...

... and lateral meniscectomies. Six partial longitudinal meniscectomies were considered under relaxation, simple creep, and combined creep loading conditions. In comparison to the intact knee, partial meniscectomy not only caused a substantial increase in the maximum fluid pressure but also shifted the location...

... properties of both the annulus and nucleus. Models were validated using published creep experiments, in which a constant compressive axial stress of 0.35 MPa was applied for 4 h. Pore pressure (PP) and effective stress ( S E ) were analyzed as a function of time following loading application (1 min, 5 min...

...Do-Gyoon Kim; Sarandeep S. Huja; Hye Ri Lee; Boon Ching Tee; Sarah Hueni Creep is an active form of time-dependent viscoelastic deformation that occurs in bone tissue during daily life. Recent findings indicate bone mineralization, which is involved in determining the elastic and plastic properties...

... accumulate damage with repetitive loading as evidenced by failure at stresses well below ultimate tensile strength, creep curve discontinuities, and by reductions in stiffness during loading. Eight normal medial collateral ligaments from female New Zealand white rabbits were cycled in tension, between 0 MPa...

... surface nodes was performed in discrete intervals to reflect the actual wear and creep damage occurring on the liner surface. Stair climbing was found to produce 49% higher volumetric wear than walking. Using a sensitivity analysis, it was found that the objective function sensitivity to the chosen design...

.... In the present study, we explored AVIC viscoelastic behavior using the micropipette aspiration technique. We then modeled the resulting time-length data over the 100 s test period using a standard linear solid model, which included Boltzmann superposition. To quantify the degree of creep and stress relaxation...

... decreases with time if the artery is cut from the loaded state, while it increases if the cut is made from the no-load state due to viscoelasticity. In both cases, the opening angle approaches the same value in 3 h . This implies that the characteristic relaxation time is about 10,000 s . Here, the creep...

...T. D. Nguyen; R. E. Jones; B. L. Boyce Tensile strip experiments of bovine corneas have shown that the tissue exhibits a nonlinear rate-dependent stress-strain response and a highly nonlinear creep response that depends on the applied hold stress. In this paper, we present a constitutive model...

... the motion of the IVD under axial cyclic loading as well as maintain computational efficiency for use in future musculoskeletal spine models. Several studies have successfully modeled the creep characteristics of the IVD using the three-parameter viscoelastic standard linear solid (SLS) model. However, when...

... acquired under different geometries, we investigate the limitations of viscoelastic parameters acquired under various imaging conditions. Quasi-static (step-and-hold and low-frequency harmonic) stimuli applied to gels during creep and stress relaxation experiments in confined and unconfined geometries...

...Jun Liao; Lin Yang; Jonathan Grashow; Michael S. Sacks We have recently demonstrated that the mitral valve anterior leaflet (MVAL) exhibited minimal hysteresis, no strain rate sensitivity, stress relaxation but not creep ( Grashow et al., 2006, Ann Biomed Eng., 34(2), pp. 315–325; Grashow et al...

... with a biphasic finite element model of the micro-indentation test, was developed to obtain the biphasic, compressive material properties of articular cartilage. The creep response and material properties of lateral tibial plateau cartilage were obtained for wild-type mouse knee joints, by the micro-indentation...

... strain-dependent swelling pressure was implemented through the introduction of a dilatational stress in nuclear elements. The model was then validated against data from quasi-static tension-compression and compressive creep experiments performed previously using mouse tail discs. Finally, sensitivity...

...A. F. Ali; M. M. Reda Taha; G. M. Thornton; N. G. Shrive; C. B. Frank In normal daily activities, ligaments are subjected to repeated loads, and respond to this environment with creep and fatigue. While progressive recruitment of the collagen fibers is responsible for the toe region of the ligament...

...John R. Cotton; Keith Winwood; Peter Zioupos; Mark Taylor We present results on the growth of damage in 29 fatigue tests of human femoral cortical bone from four individuals, aged 53–79. In these tests we examine the interdependency of stress, cycles to failure, rate of creep strain, and rate...

... friction would last a very short time after load was applied. The article gives the duration of “contact creep” as .4 seconds for roughness similar to that of cartilage 2 and about 10 seconds for roughness 5 times as tall and 10 times longer in wavelength. But the low friction of cartilage continues...

... biorheology bone hydrostatics creep sliding friction porous materials finite element analysis biomedical ultrasonics mechanical contact lubrication orthopaedics biomechanics Stoltz et al. addresses the over-four-decade controversy in synovial joint tribology as to what...

...T. L. A. Moore; F. J. O’Brien; L. J. Gibson In both cortical and trabecular bone loaded in fatigue, the stress-strain loops translate along the strain axis. Previous studies have suggested that this translation is the result of creep associated with the mean stress applied in the fatigue test...