Inflammation and soft tissue repair Flashcards
What are the 5 cardinal signs of inflammation?
Pain Heat Redness Swelling Loss of function
Is inflammation good or bad?
Good providing it is controlled.
What is inflammation?
- A response to cell injury
- Try’s to eliminate the cause of the injury and clean up the dead and dying cells and tissues.
- Protection (protects the area)
- healing
What is the purpose of inflammation?
- Neutralise and destroy the invading and harmful agent/pathogen.
- Limit the spread of harmful agents to other tissues
- Prepare any damaged tissue for repair.
Why does pain occur with inflammation?
Chemical irritation/pressure on the tissues and sensory nerve endings.
Why does redness occur?
Increase of blood flow to the area (underlying hyperaemia)
Why does pain occur with inflammation?
Chemical irritation/pressure on the tissues and sensory nerve endings.
Why does redness occur with inflammation?
Increase of blood flow to the area (underlying hyperaemia)
Why does Heat occur with inflammation?
Hyperaemia - becomes warmer as more blood rushing to the area
Why does Heat occur with inflammation?
Increase of permeability to blood vessels, therefore, increase of fluid into the tissues. (Contains fibrinogen and proteins)
Why does loss of function occur with inflammation?
Pain and swelling can limit movement
Why does loss of function occur with inflammation?
Pain and swelling can limit movement (protection)
What are the differences between infection and inflammation?
Infection will commonly have an inflammatory response.
You can have inflammation but no infection.
What is the difference between acute and chronic
Acute = Short in duration (1-2 weeks)
Chronic = more than 12 weeks
What sort of response is inflammation?
Vascular response = Leaky vessels (aim of getting tissue odema)
Cellular response
How long does the bleeding stage of soft tissue repair last for?
4-6 hrs
What are the 4 phases of soft tissue repair?
- Bleeding
- Inflammation
- Proliferation
- Remodelling
What happens during the bleeding stage of soft tissue repair.
- Bleeding 4-6 hr
- Vascular injury
- Soft tissues are disrupted and blood vessels are *severed, releasing blood plasma and peripheral blood cells into the wound site.
What happens during the inflammation stage of soft tissue repair?
Rapid onset (few hours)
Maximal reaction 2-3 days
Resolves in a couple of weeks
Mast cells detect injury to nearby cells and release histamine, initiating an inflammatory response. (triggers dilation of blood vessels enabling more blood to reach the area transporting white blood cells to assist the healing process.
Bradykinin (help transport histamines and also initiates pain response to nerve endings). and prostaglandins are also released from the damaged cells.
Describe the vascular response of inflammation
- Vasodilation & vasopermeability
- Dormant capillaries open
- Increased flow through capillaries = leaky vessels
- The above leads to increased Exudate (tissue oedma/swelling)
- Exudate - Fluid coming into the sight of bleeding which causes swelling.
- Helps dilute irritants (if infection there can help dilute).
- Helps with the clotting of a fibrin clot.
- Starts the initial reunion of intact torn tissue
Describe the cellular response of inflammation? (pacman)
*Phagocytes go to the injured area - debride wound (eat up dead and dying cells, fibrin mesh, clot etc.)
Describe the proliferation stage of soft tissue repair
Starts 24-48 hours after injury
Can last for 2-3 weeks
Fibroplasia - Fibroblasts lay down new collagen to begin the formation of connective tissue (scar tissue).
New collagen - grade 3 collagen will need to refine and remodel to become type 1 scar tissue.
Oxygen and nutrients are needed to build collagen
Angeogenesis - forms new blood vessels = basic scar formation
Describe the remodelling stage
1-2 weeks to 1 year
Refining collagen
Initially type 3 collagen (messy spaghetti) - weak, random orientation, all over the place and stuck together.
Remodels down to type 1 collagen (dried uncooked spaghetti) organised / orientated in a line with stress
What factors can affect healing ?
GENERAL Age proteing deficiency Low vit C levels Steroids and NSAID's (inhibits effect) Temperature (lower rate when cooler)
LOCAL Poor blood supply / ischemia Adhesion to bone or underlying tissue Prolomged inflammation Drying of wound Excessive movement or mechanical stress (restarts inflammation)
