Connective tissue Flashcards
What are the five major connective tissue in the body?
1) Tendons
2) Ligaments
3) Cartilage
4) Bone
5) Muscle
What are the three major components of connective tissue?
1) Fibers
2) Ground substance w/ associated tissue fluid
3) Cellular substances
Name two types of CT fibers
1) Collagen
2) Elastin
Name two types of cellular substances
1) Fibroblast (osteoblasts in bone, chondrocytes in cartilage)
2) Cells specific to each CT type
What is the function of Type I collagen? What are some examples?
Resistance to tension
Ex: Ligaments, bone dermis, fibrous cartilage, epimysium, perimsium, endomysium, fascia, joint capsule, meniscus, mature scar
What is the function of Type II collagen? What are some examples?
Resistance to intermittent pressure
Ex: Loosely packed, no fibers, very thin fibrils such as hyaline and elastic cartilage, menisci
What is the function of Type III collagen? What are some examples?
Structured maintenance for organs
Ex: Loosely packed, thin fibrils such as smooth muscle in CV and GI systems
What is the function of Type IV collagen? What are some examples?
Support and filtration
Ex: Thin amorphous such as basement membrane
Name one reason that determines tissue type:
Arrangement
How are tendons arranged?
closely packed and roughly parallel
How are ligaments arranged?
Not as parallel as a tendon, but more organized than a capsule
How are joint capsules arranged?
Loose weave of interlaced fibers, disorganized
How does collagen align?
Purposefully according to the direction of force or stress
Name four functions of CT:
1) Support
2) Strength
3) Repair
4) Mechanical connector between cells
T or F: Connective tissue are abundant and diverse.
TRUE
What type of strength does CT provide?
CT provides tensile strength
Where is CT weakest and strongest?
- Weakest where the muscle/tendon meet AND at tissue intersurface
- Strongest in the middle
Is CT vascularity generally good or poor? Which one is the exception?
Vascularity is generally poor with the exception of bone
Where are CT neural innervations found in abundance? Which CT lacks neural innervation?
- Neural innervations are abundant in muscle spindle and GTO (golgi tendon organ)
- cartilage lacks neural innervation
How does elastin (type of fiber, which is a component of CT), provide its elastic properties?
- Unique cross linking
- allows tissue to come back to normal links
Name three reasons why it’s important for PTs to understand the healing phases of CT?
1) Injury response for soft tissue is a relatively predictable manner
2) The repair process is similar in all CT
3) Know when you can stress tissues
How long does the inflammatory phase last?
1-6 days
What are the pros and cons of inflammation?
Normally has a protective role and is generally beneficial because it starts the healing process, however can be detrimental if not controlled
Name the 5 cardinal signs of inflammation:
1) Heat
2) Erythema (color/redness)
3) Pain
4) Edema
5) Functional loss
Name the four stages of the inflammatory phase:
1) Vasoconstriction (Vascular)
2) Vasodilation (Hemostatic)
3) Clot Formation (Blood cellular response)
4) Phagocytosis (Immune response)
In which phase and type of cells are first at the site of the injury?
-Clot formation->Platelets are the 1st cells at the site of the injury
Platelets bind to this and release this substance to stimulate clotting:
Platelets bind to exposed collagen and release fibrin to stimulate clotting
Which cell is the most important in the inflammatory phase?
Macrophages
Macrophages are converted from what?
Monocytes
During phagocytosis, what enzyme do the macrophages release? What does this enzyme do?
Collagenase->facilitates removal of bacteria or other foreign substances
Name four systematic effects you may expect in the inflammatory phase:
1) Overall elevation of temperature
2) Increased heart rate, possibly blood pressure
3) Elevated white blood cell count
4) General increase in metabolism
How long does the second phase, proliferation phase, last?
3-20 days
Name the four processes of the proliferation phase, which achieves coalescence and closure of the injured area:
1) Epithelialization
2) Collagen Production
3) Wound Contraction
4) Neovascularization
When does epithelialization begin?
Epithelialization can occur within 48 hours
What is the purpose of epithelialization?
Protection, loss of additional cells, fluids, etc.
What happens in epithelialization?
- Normally lays down
- Migrate and eventually for thin film over the wound
