Introduction of Skin and fascia

Dr. Navneet Kumar

Professor (Anatomy)

Introduction of structures met in dissection

• Skin • Superficial fascia• Artery, Vein ,Nerve• Deep fascia• Muscles • Bones • joints •

Dr. Navneet Kumar

Professor (Anatomy

Dr. Navneet Kumar

Professor (Anatomy

Objectives

Introduction to Skin. Fascia.

- Superficial Fascia

- Deep Fascia.

Dr. Navneet Kumar

Professor (Anatomy

Dr. Navneet Kumar

Professor (Anatomy

Skin

Structure of skin. Functions of skin. Appendages of skin.

Dr. Navneet Kumar

Professor (Anatomy

Structure of the skin

EpidermisEpidermis

Keratinized stratified Keratinized stratified squamous epithelium squamous epithelium devoid of blood vesselsdevoid of blood vessels

DermisDermis

Connective tissue containing Connective tissue containing (bl. v. lymph v., sensory nerve (bl. v. lymph v., sensory nerve endings, smooth m, hair endings, smooth m, hair follicles, sweat and sebaceous follicles, sweat and sebaceous glands) glands)

In its deep part the collagen In its deep part the collagen bundles are arranged in bundles are arranged in parallel rowsparallel rows

Dr. Navneet Kumar

Professor (Anatomy

Skin

• Layers of skin• Epidermis• Five type of layers

• Dermis• Two type of layers

Junction • Dermal papilla

• Epidermal peg (rete pegs)

Dr. Navneet Kumar

Professor (Anatomy

Skin….

• Epidermis -

1. Stratum basale• Single layer of columnar cells

2. Stratum spinosum• Several layers of polyhedral cells,

spine like process,

tonofilament

3.Stratum granulosum• Keratohyline granules

4. Stratum lucidum• Homogeneous keratin, fusiform

cells

5.Stratum corneum-non nucleated keratinized dead cells

Dr. Navneet Kumar

Professor (Anatomy)

Skin…..

Dermis

• Papillary layer• Tactile papilla• Vascular papilla• Collagen fibre

• Reticular layer Collagen fibre

• Sweat glands • Sebaceous glands• Hairs

Dr. Navneet Kumar Professor (Anatomy)

Skin……

• Thick skin

-No hairs • Thin skin • Devoid of Stratum

lucidum

Dr. Navneet Kumar Professor (Anatomy)

Functions of the Skin• 1-Protection• abrasion, invasion, water loss, UV protection• 2-Vitamin D synthesis• epidermal keratinocytes when exposed to UV

light• helps maintain health of skeleton by increasing

absorption of Ca2+• 3-Sensation• receptors for heat, cold, touch, pressure,

vibration and pain

Dr. Navneet Kumar Professor (Anatomy

• 4- Thermoregulation

• thermo receptors and sweat glands

• hypothalamus controls cutaneous arteries and sweat glands to retain or dissipate heat

• 5- Psychological and social functions

• appearance and social acceptance

• facial expression and nonverbal communication

Dr. Navneet Kumar Professor (Anatomy

• Nails• Hairs• Sebaceous glands• Sweat glands

The appendages of the skin

Dr. Navneet Kumar Professor (Anatomy)

Dr. Navneet Kumar Professor (Anatomy

Fascia

Collection of connective tissueCollection of connective tissue

Deep fasciaDeep fasciaSuperficial fasciaSuperficial fascia

Dr. Navneet Kumar Professor (Anatomy

Superficial fasciaSuperficial fascia:• Loose, mixture of adipose and loose areolar tissues.• It unites the skin to the underlying structures.• It is dense in some places as scalp, palm of hand and sole of foot

and contains collagen bundles• It is thin in the eyelids, auricle, scrotum, penis and clitoris

(devoid of adipose tissue).

Functions:• Facilitates movement of skin over underlying structures.• Passage for cutaneous vessels, nerves…

Protects the body against heat loss. Dr. Navneet Kumar

Professor (Anatomy)

Superficial fascia

Superficial Fascia• Site with Very less fat -Eyelids -Pinna -Penis • Site with more fat - Breast - Abdomen -Gluteal region

Dr. Navneet Kumar Professor (Anatomy)

It is more dense than superficial fasciaIt is more dense than superficial fascia

Collagenous bundles are more compact and more Collagenous bundles are more compact and more regularly arrangedregularly arranged

It is usually present in the form of membranes It is usually present in the form of membranes

Dr. Navneet Kumar Professor (Anatomy)

Deep fascia

A. Investing fascia

• Covers the surfaces of musclesCovers the surfaces of muscles• In the neck: it forms well-defined layers, bounds fascial In the neck: it forms well-defined layers, bounds fascial

spaces so limits spread of infection or determine the path of spaces so limits spread of infection or determine the path of infectioninfection

• In the abdomen: it is thinIn the abdomen: it is thin• In the limbs: forms a definite sheath around the musclesIn the limbs: forms a definite sheath around the muscles• Dr. Navneet Kumar Professor (Anatomy)

•

Examples of deep fascia

B. Inter muscular septa

lie between muscles lie between muscles dividing the limbdividing the limb intointo compartmentscompartments

Examples of deep fascia………..

Dr. Navneet Kumar Professor (Anatomy

Localized thickening of deep fascia around joints, hold the tendons in place, prevent bowstringing of tendon

Dr. Navneet Kumar Professor (Anatomy)

Examples of deep fascia………..

C. Retinacula

Examples of deep fascia………..

• Fibrous sheath

- eg. Carotid sheath Axillary sheath

• Fibrous capsule

-eg Parotid capsule

• Ligaments

Dr. Navneet Kumar Professor (Anatomy)

Absence of deep fascia

• Face

• Breast

• Penis

• Anterior abdominal wall

• Dr. Navneet Kumar Professor (Anatomy)