General Skin Properties Flashcards
(106 cards)
1
Q
What is the approximate surface area of skin?
A
1.5-2m2
2
Q
When is the percentage of skin damage important?
A
Burns to show likelihood of survival
3
Q
How do diseases affect skin differently?
A
Different percentages and different areas of skin affected
4
Q
What does the ‘rule of nines’ measure?
A
Extent of burns
5
Q
How many regions does the rule of nines divide the body into?
A
11
6
Q
What percentage of skin surface area does each region of the body in the rule of nines take up?
A
9% = adds up to 99% of skin
1% perineum
7
Q
Name each of the areas of the Rule of Nines (10)
A
- Head and neck
- Anterior upper trunk
- Posterior upper trunk
- Anterior arms
- Anterior lower trunk
- Posterior lower trunk
- Posterior arms
- Anterior leg (x2)
- Posterior leg (x2)
- Perineum
8
Q
What are the layers of the skin? (3)
A
- Epidermis
- Dermis
- Subcuntaenous tissue/hypodermis
9
Q
Why is a hypodermic needle called that?
A
Targets hypodermis
10
Q
What type of epithelium is the epidermis made of?
A
Stratified squamous
11
Q
What are the two types of cells in the epidermis?
A
- Keratinocytes
- Melanocytes
12
Q
What do keratinocytes produce?
A
Keratin
13
Q
What is keratin used for?
A
Hair and nails
14
Q
What is the purpose of melanin?
A
Colour/pigmentation
15
Q
How does melanin change a person’s skin? (2)
A
- Changes colour according to light/time of year
- Generations change amount and degree of lightness/darkness
16
Q
How many layers does the epidermis have?
A
4-5
17
Q
What does stratum mean?
A
Layer
18
Q
Name the layers of the epidermis from deep to superficial (5)
A
- Stratum basale
- Stratum spinosum
- Stratum granulosum
- Statum lucidum
- Stratum corneum
19
Q
What is the purpose of the stratum basale?
A
Adheres skin to basement membrane (holds skin down)
20
Q
What type of cells are in the stratum basale?
A
Columnar keratinocytes
21
Q
What type of cells are in the stratum spinosum?
A
Polyhedral (multisided) keratinocytes
22
Q
What is the purpose of the stratum spinosum?
A
Adherence and strength
23
Q
What is the purpose of the stratum granulosum?
A
First layer of waterproofing
24
Q
What are the waterproof layers of the epidermis? (3)
A
- Statum granulosum
- Statum lucidum
- Statum corneum
25
What cells make up the stratum granulosum?
3-5 layers flattened keratinocytes
26
What cells make up the stratum lucidum?
Dead keratinocytes
27
What is the stratum lucidum?
Thick skin only
28
What is the stratum corneum?
Impermeable shedding layer
29
What cells make up the stratum corneum?
Dead corneocytes 20-30 cells thick
30
What layers of the epidermis are dead? (2)
Stratum lucidum
| Statum corneum
31
Why are the stratum lucidum and stratum corneum dead layers?
Too far away from dermis layer to get nutrients
32
Why is it useful that the stratum lucidum and stratum corneum are dead layers?
Good for protection, can be brushed away
33
What does the dermis contain? (3)
- Connective tissue matrix of collagen and elastin
- Blood vessels, nerve ending and lymphatics network
- Immune cells (macrophages)
34
What two layers are the dermis made up of?
- Papillary
| - Reticular
35
What is the papillary layer of the dermis?
Interdigates with epidermis
36
What does the reticular layer of the dermis contain?
- Sweat/sebaceous glands
| - Hair follicles
37
What does the subcutaneous layer (hypodermis) contain?
Areolar connective tissue and adipose
38
Why does the subcutaneous layer contain areolar connective tissue?
Allows movement of skin on the hand
39
Why does the subcutaneous layer contain adipose? (4)
- Energy store
- Shock absorption
- Insulator
- Allows movement
40
What does the amount of fat in the subcutaneous layer change with?
Age
41
Label a skin diagram
See notes
42
What are blood vessels in the subcutaneous layer contained in?
Adipose tissue
43
Why are blood vessels in the subcutaneous layer contained in adipose tissue and what is this similar to?
Protection, like mesentry
44
Why are there blood vessels in the subcutaneous layer?
Temperature regulation
45
What are the two main functions of skin?
- Thermoregulation
| - Connection and protection
46
What are the 3 types of skin lines?
- Langer
- Blaschko
- Borges
47
What are langer skin lines?
Lines of skin tension determined by collagen fibres in dermis
48
When were Langer skin lines discovered?
1861
49
How do Langer lines spiral in limbs?
Longitudinally
50
How do Langer lines spiral in trunk?
Transversally
51
How do Langer lines spiral parallel in relation to what creases?
Limb flexor
52
What is important to the speed skin heals after cutting?
The direction the cut is made in
53
What adherement is important for the way we heal?
Skin to basement membrane
54
What are Blaschko lines?
Lines of normal cell development
55
What does the way cells form in development influence?
The way rashes form in disease
56
Can Blaschko lines be seen normally?
No, normally invisible
57
What diseases can Blaschko lines manifest in?
- Lichen Planus
| - Lupus
58
What are Borges lines?
Relaxed skin tension lines
59
What are furrows in Borges lines caused by?
Pinching
60
What is a common problem in plastic surgery in relation to Borges lines?
Going against them creates a worse appearance of scars
61
What is the scalp made up of? (2)
- Thin skin
| - Subcutaneous tissue
62
How many layers does the scalp have?
5
63
What does the scalp overlie?
Neurocranium (skull)
64
What are the borders of the scalp?
Superior border occipital bone to supraorbital margin of frontal bone
Laterally extends over temporal fascia to zygomatic arches
65
What are the layers of the scalp?
- Skin
- Connective tissue (dense)
- Aponeurotic layer (galea aponeurotica)
- Loose connective tissue
- Pericarnium
66
What is another word for face?
Viserocranium
67
Why can scalp wounds be alarming? (5)
- Profuse bleeding
- Swelling
- Bruising
- White aponeurosis
- Brain injury potential
68
Why do scalp wounds profusely bleed?
Good vascular supply to scalp
69
What is the solution for scalp wound profuse bleeding?
Apply direct pressure
70
How can scalp wounds cause swelling?
Blood can expand the loose connective tissue layers, raising skin like egg boils
71
How can a scalp wound cause bruising? (2)
Tissue oedema goes down into face
| Bruising extends downward up to 3 days later - worse before better
72
What can a white aponeurosis in scalp wounds be mistaken for?
"Down to the bone"
73
What is the treatment for scalp wounds in adults?
Suture/staple
74
What is the treatment for scalp wounds in children?
Glue
75
Why does skin need to be flexible?
To accommodate movement of muscles and bones
76
What two types of strength are found in the skin?
- Tensile
| - Elastic
77
What does the flexibility of the skin change with?
- Age
- Disease
- Pregnancy
78
What is lost in the skin with aging?
Elastic fibres of dermis
79
What does loss of elastic fibres of dermis in aging cause? (2)
- Wrinkles
| - Skin sagging
80
What are stretch marks in pregnancy also known as?
L striae gravidarum
81
What are stretch marks in pregnancy caused by?
Overstretched skin due to rapidity of change
82
What are stretch marks caused by disease known as?
L. striae cutis distensae
83
What direction are L. striae cutis distensae in?
Longitudinal
84
What are L. striae cutis distensae seen in? (2)
- Obesity
| - Hypercortisolism
85
Why are L.striae cutis distensae seen in hypercortisolism?
Protein changes and reduced collagen cohesion = weakening of skin around abdominal area
86
What common condition to do with fluid causes weakening of skin around abdominal area?
Ascitis
87
What is ehlers danlos?
Genetic mutation in collagen causing hypermobility of joints and skin elasticity
88
What direction are Ehlers Danlos striae found in?
Horizontal
89
What 3 things affect facial appearance?
- Bone structure
- Fat distribution
- Facial muscles
90
Why do babies have chubby cheeks?
To suckle properly
91
What 4 factors form the idea of "normal skin"?
- Location
- Pigmentation
- Damage
- Function
92
How does location form the idea of "normal skin"? (2)
- Hairless/hairy skin
| - Thickness
93
How does pigmentation form the idea of "normal skin"? (2)
- Melanin distribution
| - Population
94
What types of damage form the idea of "normal skin"? (3)
- Sun
- Aging
- Disease
95
What functions form the idea of "normal skin"? (6)
- Protection
- Containment
- Absorption
- Secretion
- Heat regulation
- Sensation
96
What 3 ways could the appearance of our "normal" skin/hair/nails impact us?
- Influence personality
- Imply belief
- Display Health
97
What is responsible for age related damage to the skin?
UVA
98
Outline the effects of age on the skin (5)
- UVA permeates deeper into dermis normally containing collagen and elastin
- Reduced collagen and elastin
- Less vascularisation
- Unsupple skin
- Uneven surface
99
What are the two main age related conditions found in the skin?
- Actinic (solar) elastosis
| - Solar keratosis
100
What is actinic elastosis?
Abnormal elastin accumulation in skin dermis and eye conjunctiva due to cumulative effects of prolonged sun exposure
101
What is actinic elastosis known as?
Photoaging
102
Describe the appearance of actinic elastosis (5)
- Skin thinner
- Epithelium thinner
- Uneven surface
- Wrinkles
- Reduced skin elasticity
103
What are sun spots?
Localised areas of hyperpigmentation in aging/pregnancy
104
What is solar keratosis? (3)
- Scaly skin area caused by repeated sun damage
- UV radiation induces abnormal cell growth
- Localised skin damage/hyperkeratosis
105
What is solar ketatosis caused by?
Radiation induces abnormality in cell growth factor
106
What are the effects of smoking on the skin? (7)
- Grey and dull
- Premature aging (10-20 years)
- More prominent facial wrinkles
- Underlying prominent bony contours
- Thin skin
- Orange/purple/red complexion
- Increased psoriasis risk
