Fundamentals

Question 1

What are the phases and timings of wound healing?

Answer 1

Inflammatory (days 1-6)
Fibroproliferative (Day 4 - week 3)
Maturation/remodelling (week 3 - 1 year)

Question 2

What phase of wound healing 2 weeks post injury?

Answer 2

Fibroproliferative

Question 3

Outline the stages of the inflammatory phase of wound healing

Answer 3

Vasoconstriction, coagulation, vasodilation and increased vascular permeability, chemotaxis, cell migration

Question 4

Outline the stages of cellular migration during the inflammatory phase of wound healing

Answer 4

Margination, diapedesis, fibrin deposition

Question 5

What is the predominate cell type within a wound during the first 48h

Answer 5

Neutrophils (24-48h)

Question 6

What is the predominate cell type within a wound during 48-96 hours?

Answer 6

Macrophages (48-96 hours; 2 days - 2 weeks)

Question 7

Which cell type is most critical for wound healing?

Answer 7

Macrophages

Question 8

What are the hallmark features of a chronic wound?

Answer 8

Failure of a wound to progress from the inflammatory to the fibroproliferative phase, resulting in prolonged and unresolved inflammation

Question 9

What is the role of debridement in the setting of chronic wounds?

Answer 9

Remove inflammatory mediators and senescent cells to turn a chronic wound into an acute wound to reset the wound healing process

Question 10

Outline the stages of the fibroproliferative phase of wound healing

Answer 10

Matrix formation, angiogenesis, epithelisation

Question 11

What is the dominant cell type within a wound one week following an injury?

Answer 11

Fibroblasts

Question 12

When are fibroblasts present in a wound post-injury?

Answer 12

Day 2-3

Question 13

Outline tor production of glycosaminoglycan

Answer 13

Hyaluronic acid > chondroitin-4-sulfate, dermatan sulfate, heparin sulfate > collagen

Question 14

What is the difference between angiogenesis and vasculogenesis?

Answer 14

Angiogenesis = formation of new blood vessels from existing ones

Vasculogenesis = formation of new blood vessels de novo

Question 15

Outline the remodelling phase of wound healing

Answer 15

Week 3 to 1 year

Equilibrium in collagen synthesis and breakdown

Type I collagen replaces type III collagen

Decrease in GAGs, water content, vascularity and cellular population

Question 16

What is the tensile strength of a wound at 1 week?

Answer 16

3%

Question 17

What is the tensile strength of a wound at 3 weeks?

Answer 17

30%

Question 18

What is the tensile strength of a wound at 3 months?

Answer 18

80%

Question 19

What is the normal ratio of type I to III collagen?

Answer 19

4:1

Question 20

Type I collagen

Answer 20

90%
Skin, bone and tendon

Question 21

Type II collagen

Answer 21

Cornea
Hyaline cartilage

Question 22

Type III collagen

Answer 22

Vessel and bowel walls
Uterus
Skin

Question 23

Type IV collagen

Answer 23

Basement membrane

Question 24

Where are multipotent epithelial progenitor cells found?

Answer 24

Bulge stem cells in hair follicle

Question 25

Outline the stages of epithelisation

Answer 25

Mobilisation (loss of contact inhibiton), migration (contact inhibition re-established), mitosis, differentiation

Question 26

What cell type is implicated in Dupuytren's?

Answer 26

Myofibroblasts

Question 27

Mutation in which gene is found in Ehlers-Danlos?

Answer 27

COL5A1 COL5A2 COL1A1

Question 28

Mutation in which gene is found in progeria?

Answer 28

LMNA

Question 29

Outline features of progeria

Answer 29

limited growth, full body alopecia, beaked nose, atherosclerosis

Question 30

Mutation of which gene found in Werner

Answer 30

WRN

Question 31

Pseudoxanthoma elasticum

Answer 31

Question 32

Cutis laxa

Answer 32

Question 33

How does vitamin A deficency effect wound healing?

Answer 33

Supplementation reverses delayed wound healing from steroids

Question 34

How is vitamin C involved in wound healing?

Answer 34

Vital for hydroxylation of amino acids essential for collagen synthesis

Question 35

What factors affect wound healing?

Answer 35

Systemic: co-morbidities, drugs (steroids), smoking, vitamin deficiencies and nutrition Local: Oxygen delivery, infection, biofilm, radiation,

Question 36

What is a hypertrophic scar?

Answer 36

Elevated scar within borders of original scar. Composed of type III collagen orientated parallel to epidermal surface with abundant myofibroblasts. develop 1-2 months post injury.

Question 36

What is a keloid scar?

Answer 36

Elevated scar outside borders of original scar. Disorganised type I and III collagen bundles. Form weeks-years post injury.

Question 37

When is peak tensile strength of a wound?

Answer 37

41-60 days post injury (80% of original strength)

Question 38

How can methylene blue be used to aid surgical debridement of chronic wounds?

Answer 38

Applied on induction, wound wiped clean. Stains eschar, granulation and necrotic tissue thus identifying tissue to be debrided

Question 39

Outline the strength and resorption times of absorbable sutures (VR, monocryl, PDS)

Answer 39

Question 40

What are antimicrobial sutures coated in?

Answer 40

Triclosan Blocks bacterial fatty acid synthesis