Kania's "Fascia" Lecture - Kathleen Flashcards
Fascia definition and components, according to Dr. Kenia
Fibrous connective tissue masses that binds together the structures of the body
Matrix made up of proteoglycans, Polysaccharide chains: - glucosamine - hyaluronic - chondroitin sulfate
Glycosaminoglycans
Hydrophilic sugar
- determines oncotic pressure of surrounding tissue
Provides form and stiffness for connective tissue
Composition of fascia
fibroblasts, fibroglia, collagen fibrils, elastic fibrils
Properties of loose/areolar connective tissue
Stretchy, connects many adjacent structures
Matrix is soft, thick gel with hyaluronic acid
Creep
Myofascial adaptation as a result of sustained stress
Continued deformation of a viscoelastic material under constant load over time
- release of stored kinetic energy
- tendency of solid material to slowly move or deform permanently under stress
- undergo deformation to accommodate load
Hysteresis
Myofascial return to initial state after release of load
- doesn’t regain pre-load structure
- generally involves lag time, as this implies a cause and effect sequence of events
Change in energy content of tissue due to permanent changes
Stress
force normalized over the area on which it acts
- normal stress perpendicular to cross-section
- shear stress is parallel
Can deform a structure, permanently or temporarily
Strain
Change in shape due to stress
Stiffness
ratio of load to the deformation/strain it causes
Compliance
inverse of stiffness
“Your mom is compliant”
Characteristics of elastic materials
Amount of deformation is the same for a given amount of stress
Material returns to original length or conformation when the stress is removed
Characteristics of viscoelastic materials
Viscous
- nonlinear properties
- magnitude of stress depends on rate of loading
- stored mechanical energy not completely returned when stress is removed
Stored mechanical energy of tissue after stress is applied
Hooke’s law applies - tissue acts like a spring under stress, stores E
What is the yield point for tissue?
Point at which tissue will permanently retain stress energy, molecular components permanently displaced
What is residual strain?
Difference in tissue at molecular level after applied load is released, with a higher level of strain
(Difference between hysteresis and residual strain is unclear)