Phases of Wound Healing

Question 1

What are the 3 phases of wound healing?

Answer 1

1) Inflammatory phase
2) Proliferative phase
3) Maturation phase

Question 2

How long does the Inflammatory Phase last?

Answer 2

1-10 days

Question 3

How long does the Proliferative Phase last?

Answer 3

3-21 days

Question 4

How long does the Maturation Phase last?

Answer 4

7 days-2 years

Question 5

What processes/cells characterize the Inflammatory phase? (3)

Answer 5

• Temporary repair mechanisms re-establish homeostasis through platelet activation and the clotting cascade
• Mast cells, neutrophils, and leukocytes kill bacteria and remove debris/necrotic tissue
• Process establishes a clean wound bed –> tissue restoration/permanent repair signaled to begin

Question 6

What processes/cells characterize the Proliferative Phase? (3)

Answer 6

• Capillary buds/granulation tissue fill wound bed making a support structure for epithelial cells
• Keratinocytes, endothelial cells, fibroblasts active -> formation of collagen matrix
• Wound closure through epithelialization/wound contraction

Question 7

What processes/cells characterize the Maturation Phase? (2)

Answer 7

• Initiated when granulation tissue/epithelial differentiation begin to appear in wound bed
• Fiber reorganization/contraction shrink and smooth scar

Question 8

Properties of immature scars

Answer 8

Red, raised, and rigid

Question 9

Properties of mature scars

Answer 9

Pale, flat, and pliable

Question 10

What is the tensile strength of scars compared to pre-injury strength?

Answer 10

Up to 80% pre-injury strength

Question 11

What creates a “chronic wound”?

Answer 11

Anti-inflammatory/immunosuppressive meds, arterial insufficiency, and conditions that alter immune responses (DM, alcoholism, AIDS) limits healing process where proliferative phase is never reached.