Skin Anatomy and Facts

The skin is composed of three layers: epidermis (outermost), dermis (inner), and hypodermis (innermost).

The outermost layer of the skin.

The inner layer of the skin, under the epidermis.

The innermost layer of the skin, mostly fat.

Sensory cells in the epidermis, involved in touch sensation.

Immune cells in the epidermis, part of the skin's defense.

Sweat glands found throughout the skin, producing sweat.

Larger sweat glands found in specific areas, active in puberty.

Protection, sensation, temperature regulation, vitamin D production.

Age-related changes in skin, increased vulnerability and some benign changes.

Thinning of skin layers, increasing risk of injury in older adults.

Folds and creases in the skin, due to loss of elasticity.

Age-related discoloration on the skin.

Decreased moisture in the skin due to aging.

Age-related decrease in hair production, especially on scalp.

Reduced number and size of capillary vessels, affecting wound healing.

Fewer sweat and oil glands, leading to dry and scaly skin.

Lower levels of male hormones affecting sebaceous gland function.

Decreased hair growth, especially on certain body parts.

Skin damage from sun exposure, marked by wrinkles, elasticity loss, and pigmentation changes.

Evaluating skin, hair, nails, and mucous membranes in a well-lit environment.

Redness or flushing in lighter skin tones, often due to inflammation or increased blood flow.

Redness in darker skin tones, potentially masked by melanin; can be hard to detect without additional cues.

Assessment of skin elasticity and its ability to return to normal position after being pinched.

Visual examination of skin for color, moisture, texture, lesions, and circulatory conditions.

Increased red blood cells, leading to capillary stasis.

Exposure to carbon monoxide causes bright, cherry-red coloring in the face and upper body.

Poor venous return in legs causes hemosiderin staining and skin breakdown (stasis ulcers).

Problems with venous return resulting in edema, hyperpigmentation, and warmth in legs.

Bluish discoloration due to low oxygenated hemoglobin.

Brown or rusty discoloration due to iron buildup in the skin.

Increased red blood cells and capillary stasis. Look for ruddy/blue coloration in face and other areas.

A key sign of carbon monoxide poisoning.

Elevated serum bilirubin (over 2.5-3 mg/dL) due to liver problems or blood cell breakdown (like severe burns).

Yellowing first shows in the whites of the eyes (sclera), hard palate, and mucous membranes, then spreads to the skin.

Bluish skin discoloration due to low oxygen in the blood, often from heart or lung problems.

Bluish discoloration of skin, especially in the extremities (like hands and feet) due to cold or anxiety.

Examine the sclera (whites of the eyes) for yellowing near the edge (limbus), avoiding confusion with normal yellowish deposits.

Undermining refers to the extension of a wound beneath the surface skin, creating a hidden cavity. It can make a wound appear smaller than it actually is.

Epibole occurs when the edges of a wound curl inward, like a rolled-up carpet. This can delay healing and trap bacteria inside the wound.

Measuring a wound's diameter and depth helps track its progress, evaluate treatment effectiveness, and determine the appropriate type of care.

Induration refers to abnormal firmness in the tissue, often due to inflammation or infection. It can be felt with your fingers and indicates a problem beneath the surface.

A skin biopsy is a small tissue sample taken from a lesion, used to rule out malignancy and establish an accurate diagnosis.

Patch testing helps identify substances a person is allergic to, by applying small amounts of allergens to normal skin.

Skin scrapings are used to diagnose fungal infections and parasites like scabies. The scraped material is examined under a microscope.

Photographs document the nature and extent of skin conditions, track their change over time, and help monitor progress or improvement with treatment.

An injury to the skin and underlying tissue, usually caused by prolonged pressure on the same area. It can include necrotic tissue, bleeding, or scarring.

A linear crack in the skin that may extend to the dermis. It can be caused by dryness, infection, or prolonged pressure.

Flakes of dead skin cells (epithelium) that can adhere to the surface of the skin. They can vary in color and texture.

Dried residue of serum, blood, or pus on the skin surface. It can be large and adherent.

A mark left on the skin after a wound or lesion heals. Connective tissue replaces damaged tissues.

A raised, thick, and irregular scar that forms due to excessive collagen formation during healing.

Thinning and dryness of the skin, usually due to loss of collagen and elastin.

Thickening and roughening of the skin, usually due to chronic irritation or scratching.

The area inside a wound that is being treated. It should be inspected for tissue types, exudate, color, and odor.

Dead tissue in a wound. It can be yellow, white, or gray.

Yellow, white, or gray dead tissue in a wound. It needs to be removed for the wound to heal.

New, reddish connective tissue that forms on the surface of a wound during healing.

The tissue that covers the surface of a wound during healing.

Fluid that comes from a wound.

Dead tissue impedes healing and can harbor bacteria. By removing it, you promote healthy wound healing.