CH 4: Properties of Connective Tissue Flashcards
What is the amount of movement available to a joint moving within its anatomical range?
ROM
What results from shortened muscles that may lead to faulty postural alignment, which may lead to injury and joint dysfunction?
Muscular imbalances
What may results from muscular imbalances from shortened muscles?
Postural alignment, injury, joint dysfunction
What are the benefits of flexibility and stretching?
- Improves balance
- Easier to strength and endurance train
- Injury prevention
- Quicker recovery from workouts
- Reduces postexercise soreness
- Facilitates relaxation
What are the building blocks of protein?
Amino acids
What the building blocks of collagen?
Tropocollagen
What are made of short subunits (fibrils) and are found in varying amounts within different connective tissues?
Collagen
What are types of connective tissues?
- Bone
- Tendon
- Muscle
- Skin
- Hyaline Cartilage
- Joint Capsule
What is a protein building block of connective tissue?
Collagen
What provides strength needed to withstand high levels of tension and force during movement and exercise?
Collagen
What type of collagen is the most abundant in the body?
Type I
What type of collagen fibers are thick and have the ability to resist pulling?
Type I
What type of collagen fibers display very little elongation when placed under tension?
Type I
What type of collagen fibers is thinner an has less tensile strength?
Type II
What type of collagen fibers are primarily found in articular cartilage (at end of bones) and nucleus pulposus (vertebral disk)?
Type II
What type of collagen fibers serves mainly in structural support capacity?
Type III
What type of collagen fibers is found in expansible organs (arteries, liver, lungs)?
Type III
What type of collagen fibers is common in fast growing or healing tissue and is often seen at easy stages of wound repair?
Type III
What type of collagen fibers replaces type III collagen in wound repair and is tougher?
Type I
What is a structural protein present in tendons in amounts of less than 1%?
Elastin
What assists collagen in recovery of tissues after stress (initial loading of the tissue)?
Elastin
Tissues with greater amounts of elastin typically result in?
More flexibility
What is recorded in force/area?
Stress/Load
What is directly related to the magnitude of force an inversely related to the unit area but is independent of the amount of material?
Stress/Load
What is another name for strain?
Deformation
What is usually dimensionless because the units of measure cancel out each other, but units are often provided?
Strain/Deformation
What factors affect the relationship of stress/load and strain/deformation?
- Material properties used
- Magnitude of stresses
- Rate of stress application
What represents how a slightly pulled tissue (ligament) produces only a small amount of tension within the tissue?
Toe region
What indicates that the collagen fibers within the tissue must first be pulled taut before stress can be induced?
Toe region
What does the minimal amount of tension in the toe region result in?
The slack of tissue being taken up with no stretch being encountered
What represents a linear change in strain which occurs if tissue continues to be pulled at higher stress levels?
Elastic region
What is defined as the change in force per unit change in length?
Stiffness
What occurs when tissues are stiffer?
The steeper (more vertical) the slope
What are tissues with less stiffness considered?
More compliant
What is the point where an increasing level of stress on the tissue results in proportionately increased changes in tissue length (result of a microscopic failure of tissue)?
Plastic region
What region does the slope begin to flatten in the stress-strain relationship?
Plastic region
What is termed because of tissue damage resulting in permanent deformation (plastic deformation)?
Plastic zone
What is not recoverable in its entirely when the load is removed resulting in a change in its resting length with the stress-strain relationship?
Plastic energy
Continued stretch in the plastic region results in?
Initial point of failure
The toe region can include strains up to?
3%
The elastic region can include strains up to?
6-10%
The plastic region can include strains up to?
10-15%
What part of the stress-strain relationship occurs when a load is applied then returns to normal when the load is removed?
Elastic zone
What is the intensity of internal force?
Stress/load
What can be compressive, shear, or tensile?
Stress/load
What equals the change in length or original length of a tissue?
Strain/deformation
What is the relative measure of deformation of a body as a result of loading?
Strain/deformation
What is the stress or strain behavior that is time rate dependent?
Viscoelasticity
What refers to the ability of a material to return to its original state following strain/deformation (change in length or shape) after a removal of stress/load?
Elasticity
What term is associated with a rubberband (rapidly conforms to new length and returns to original resting state when stress/load removes)?
Elastic deformation
What refers to the ability of a material to resist a change in form or to dampen/lessen shearing forces?
Viscosity
What is equivalent to slow-pouring molasses?
Viscosity
What has time-dependent properties?
Viscoelasticity
What stress rate has greater amounts of strain or elongation?
Slow
What is sensitive to the applied force duration?
Viscoelastic materials
What type of stress should be applied to gradually lengthen tissues?
Constant/repeated stress of long duration
What simply means the gradual increase in tissue length that occurs when maintaining a constant stress or force?
Creep
When are creep changes more pronounced?
Slow-velocity stretching
What type of deformation favors high-force, short-duration stretching?
Elastic tissue deformation
What type of deformation favors low-force, long-duration stretching?
Plastic tissue deformation
What occurs when a longer duration of applied force is applied to the tissue?
Greater the deformation or stretching
What occurs when a viscoelastic material experiences a constant strain (no deformation occurs)?
Stress-relaxation (force-relaxation)
What occurs when high initial stress is placed on a tissue decreases over time until equilibrium is reached and stress equals zero resulting in relaxation of tissue; no change in length is produced?
Stress-relaxation (force relaxation)
What occurs when a muscle is help at a certain length over time, a reduction in stress would occur, but there would be no change in length (no stretch occurs)?
Stress-relaxation (force relaxation)
What results in a gradual increase in tissue length?
Creep
What occurs when the longer the duration of the applied force, the greater the deformation or stretching of tissue?
Creep
What term is associated with a spoon snapping?
Plastic deformation
What term occurs when a low degree of stress is applied and will slowly deform to accommodate to new shape, but if stress is suddenly applied with great force, it will break?
Plastic deformation
What is the ability of tissues to return to their previous resting state but does not imply that permanent elongation or microscopic damage has not occurred?
Recovery
What is force dependent on slow rates of stress and is used to describe permanent change in a tissue?
Plastic deformation
What is produced with increasing levels of stress?
Increase in collagen within ligaments and tendons
What occurs by decreasing the level of stress?
Weakening connective tissues
What is the discrepancy between the mechanical energy used to perform tissue stretch and the energy needed to return the tissue to its original shape?
Hysteresis
What types of temperature increases rate of creep?
High temperatures
What is the therapeutic limit of heat?
45C (113F)
What is the range of temps that increase rate of creep?
37-40C (98.6-104F)
What occurs to the tissue when it reaches the therapeutic limit?
The greater degree of deformation/elongation before tissue failure
How do you produce creep with a connective tissue structure with heat?
Heat it, use a large load over a long period of time
What occurs to connective tissues at high temps?
Less microscopic damage under stress
