Skin and Fascia

Question 1

Explain the rule of 9 and its application

Answer 1

The rule of 9

• Head and neck - 9%
• Each upper limb - 9%
• Front of the trunk - 18%
• Back of trunk (including buttocks) - 18%
• Each lower limb - 18% (in child 13.5%)
• Perineum - 1%

It is valuable while assessing the area affected by burns

Question 2

Du Bois Formula

Answer 2

A = W(in kg) x H(in cm) X 71.48 sq cm

Question 3

Five pigments of the skin

Answer 3

1. Melanin- Brown in colour, present in the germinative zone of the epidermis
2. Melanoid- Resembles melanin (hence the name), present diffusely across the epidermis
3. Carotene- Yellow to orange in colour, Present in stratum corneum, fat cells of dermis and superficial fascia
4. Haemoglobin- Purple
5. Oxyhaemoglobin- Red in colour, present in cutaneous vessels

Question 4

Origin of epidermis

Answer 4

Ectodermal

Question 5

Features of epidermis

Answer 5

Superficial
Avascular
Stratified squamous epithelium

Question 6

Structure of Epidermis

Answer 6

Superficial cornified layer
- Anucleate flattened cells ( cells of the deepest layer proliferate and pass towards the surface, as they migrate the the superficial surface it becomes more flattened and loses it nucleus)
Deep germinative zone
- ‘dope’ positive melanocytes (melanoblasts, dedritic cells, or clear cells) of neural crest origin, which synthesise melanin are present

Question 7

Origin of dermis/corium

Answer 7

Mesoderm

Question 8

Langer lines

Answer 8

Flexor or Cleavage line present in the papillary layer of the dermis as parallel bundles of white fibrous tissue
Longitudinal - Limbs
Horizontal - Neck and trunk

Question 9

Lineae Gravidarum

Answer 9

White scarring formed due to ruptures of white fibrous tissue in the papillary layer of the dermis due to overstretching of the skin