1. DEBRIDEMENT: ANATOMY and PHYSIOLOGY*
07/16/96
DEBRIDEMENT: ANATOMY and PHYSIOLOGY
Professor Donald G. MacLellan
Executive Director
Health Education & Management Innovations *

2. ANATOMY and PHYSIOLOGY
Epidermal Layers
Dermis – Anatomy & Appendages
Vascular System
Nervous System

3. EPIDERMIS 4 MAIN CELL TYPES:
Keratinocytes - main cell type; arranged in 5 layers; perpetually being generated
Melanocytes - melanin production; brown skin colour
Merkel Cells - mechanoreceptor function
Langerhan’s cells – immune function

4. Stratum Germinativum Deepest layer, in contact with dermis
Single layer of cells
Only layer of epidermis capable of cell division
Contain melanocytes

5. Melanocytes Capable of producing the brown pigment, melanin
Melanin can absorb energy from ultraviolet (UV) light
UV light contains high energy photons that can damage DNA – mutations
Melanin can prevent damage to DNA, helps to prevent skin cancer

6. Stratum Spinosum Several layers thick
Cells of this layer begin to produce keratin
Keratin is a water-insoluble protein that protects the body from water

7. Stratum Granulosum Multilayer and cells become compressed
Keratin crystallizes into granules within the cytoplasm
Cells are metabolically dead

8. Stratum Lucidum Clear layer of cells Only present in thick skin
Cells nothing more than a bag of keratin

9. Dermis Papillary layer:
1/5 of dermis – loose areolar connective tissue
Highly vascular
Dermal papillae - fingerprints

10. Dermis Reticular layer: Dense irregular connective tissue
Sebaceous (oil) glands
Hair follicles
Ducts of sudoriferous (sweat) glands
Meissner’s and Pacinian corpuscles

11. 1.

12. 2. Protection - physical abrasion - dehydration
- ultraviolet radiation
3. Sensation
- touch
- vibration
- pain
- temperature

13. 4. Excretion
5. Immunity/ Resistance
6. Blood Reservoir
- 8 to10 % in a resting adult
7. Synthesis of vitamin D - UV light
- aids absorption of calcium

14. Physiology of Aged Skin*
07/16/96
Physiology of Aged Skin
Functional Decrement:
- Epidermal turnover
- Barrier function/ chemical clearance
- Inflammatory response
- Mechanical protection *

17. Nervous System
A Dermatome is an area of skin associated with a pair of dorsal roots from the spine