Tissue Repair Flashcards
What processes does tissue repair require?
- Hemostasis
- Inflammation
- Regeneration
- Fibrosis
- Remodeling
What forms a scar?
Occurs in a series of steps when repair cannot be effected by regeneration
What are the steps of scar formation?
- Angiogenesis is promoted by vascular endothelial growth factor (VEGF) and the fibroblast growth factor (FGF) family of growth factors
- Platelet-derived growth factor (PDGF), fibroblast growth factor 2 (FGF-2), and transforming growth factor beta (TGF-beta) drive fibroblast activation
- TGF-beta, PDGF, and FGF drive ECM deposition. Cytokines IL-1 and IL-13 stimulate collagen production
What are the types of wound healing?
Healing by first intention and healing by second intention
What is healing by first intention?
Occurs when wounds are closed physically with sutures, metal staples, dermal adhesive etc.
What is healing by second intention?
Occurs when wounds are allowed to heal by wound contraction.
What is a hypertrophic scar?
Results in a prominent scar that is localized to the wound due to excess production of granulation tissue and collagen.
What is a keloid formation?
Excess production of collagen that is predominantly type III.
Common in African americans, tends to affect the earlobes, face, neck, sternum, and forearms
What is a desmoid formation?
- Exuberant proliferation of fibroblasts and other connective tissue elements
- Recur after excision- 20% to 50%
- Can occur anywhere but Abdominal wall is the most common site in women
- Painless lump
- Frequently associated with previous trauma
What is a contracture?
- Exaggerated wound contraction
- Commonly seen after serious burns
- Consequences:
Compromised joint movement and
Joint deformities - Most common sites:
Palms, the soles, and the anterior aspect of the thorax
