Section 22: Tendon / Ligament Mechanical and Viscoelastic - - PowerPoint PPT Presentation

Section 22: Tendon / Ligament – Mechanical and Viscoelastic Mechanical and Viscoelastic Properties

22-1

Viscoelasticity Viscoelasticity

• Time dependent behavior in soft hydrated cells & tissues

p y

• Linear and nonlinear viscoelastic models frequently used

to phenomenologically describe mechanical behavior of ligaments and other biological tissues

• Usually model based on curve fitting creep or relaxation

i t t l l f l di experiment at one level of loading

• Most commonly used model is quasi-linear

viscoelasticity (QLV) viscoelasticity (QLV)

22-2 From: Vanderby

Viscoelasticity Viscoelasticity

• Increased resistance with

increased loading rate

• Creep = under constant load

ft ti ill ti t soft tissue will continue to gradually deform

• If compressive force is applied

If compressive force is applied slowly, syringe offers little resistance I d t f f

• Increased rate of force,

increased resistance to rate of motion of syringe

22-3 From: Justice

y g

Viscoelastic Behavior

22-4 From: Vanderby

22-5 From: Garner

22-6 From: Garner

22-7 From: Garner

22-8 From: Al-Tayyar

22-9 From: Al-Tayyar

22-10 From: Al-Tayyar

22-11 From: Al-Tayyar

22-12 From: Al-Tayyar