Med term Ch 3 and 4

functions of the integumentary system

protection, water resistance, temp regulation, vitamin D synthesis, sensation, social functions, excretion and secretion

3 layers of the skin (most superficial to deepest)

epidermis —> dermis —→ hypodermis

layers of the epidermis

stratum corneum (keratinized skin cells), stratum lucidum, stratum granulosum, stratum spinosum (living keratinocytes and dendritic cells), stratum basale (tactile cells and melanocytes)

two layers of the dermis

papillary layer and reticular layer

what kind of stuff is in the dermis

collagen fibers, blood vessels, nerves, sweat glands, sebaceous glands, hair follicles, nail roots

what is in the hypodermis

subcutaneous fat, blood vessels, and nerves

functions of hypodermis

regulate body temp, protects vital organs

intradermal injection

injected at a 15 degree angle into the epidermis

subcutaneous injection

injected at a 45 degree angle into the hypodermis

intramuscular injection

injected at a 90 degree angle into the muscle underneath the hypodermis

transdermal injection

“injected” into the dermis using an adhesive transdermal patch

branch off of hair follicles to secrete a mix of sebum and broken down keratin to lubricate and waterproof the skin and protect from infection

sebaceous glands

originate from hair matrix and hair bulb and is slowly pushed upward and past the skin’s surface as hair cells continue to develop

hair

located all over the body and function to produce sweat that cools the body and, in some areas, produce an odor that results from a reaction between skin bacteria and gland secretion

sweat glands

cells divide at the nail matrix (protected by the cuticle) and are pushed outward to form hard parallel fibers of keratin to form the nail

nails

inflammatory skin condition causing a swollen red rash, itchiness, and potentially blistering

dermatitis

type of dermatitis used as a general term for inflamed and itchy skin; when scratched, the skin becomes dry, red, and scaly patches

eczema

dermatitis caused by an allergy to metal, allergens, perfume, etc.

atopic/allergic dermatitis

direct contact with irritants or allergens like soap, cleaning products, etc.

contact dermatitis

mostly in the lower leg when slow return of blood in veins and fluid accumulation affects skin nourishment

stasis dermatitis

come from the basal layer of the epidermis; the most common form of skin cancer and does not metastasize

basal cell carcinoma

comes from middle epidermal layers, requires surgical removal but can metastasize to lymph nodes if not careful

squamos cell carcinoma

comes from melanocytes in the basal layer of epidermis; least common, most dangerous; metastasizes really quickly and can be fatal

malignant melanoma

the pressure between the surface a patient is lying on and the resting bony projection cuts off the skin’s blood supply if a patient has not moved for a long time; thin and dry skin (elderly mostly) and poor nutrition can also diminish the skin’s protective layer and cause pressure ulcers

what causes a pressure ulcer

effects of a pressure ulcer

skin’s protection is compromised and wound can become infected

congenital lesion/nevus

birthmark caused by abnormal pigmentation or sudden increase in blood vessels; sometimes goes away in early childhood

types of skin infections

viral, fungal, parasitic, bacterial

warts

viral skin infection caused by papillomavirus in epidermis

chickenpox

viral skin infection caused by varicells-zoster virus with macules (discolored flat bump), papules (small solid elevation) , and vesicles (small fluid-filled sacs)

shingles

viral skin infection caused by herpes-zoster and it can remain dormant before erupting or being passed on genetically

athletes foot

tinea pedis

capitis tinea

ringworm of the scalp

corporis tinea

ringworm of the skin and hands

cruris tinea

jock itch infection of the groin

candida albicans

yeast infection of skin, nails, and mucous membranes

mucocutaneous candidiasis

fungal infection of mouth, vagina, or skin in adults

lice

parasitic infestation causing pediculosis when lice attach their eggs to hair and clothing

mites

parasitic infestation causing an intense rash called scabies on the genitals, waist, breasts, and armpits, and eggs laid under the skin

staph infection (staphylococcus aureus)

bacterial infection causing pimples, boils, carbuncles, and/or impetigo

lupus

autoimmune collagen disease causing specific red rashes and affects the kidneys, brain, heart, lungs, and joints

rosacea

facial rash, no other complications although confused with lupus

scleroderma

autoimmune collagen disease causing hardening of the skin, joint swelling, pain, stiffness, and similarly affects internal organs; no treatment and unknown cause; correlation with breast cancer

psoriasis

itchy, flakey, red patches of skin with scales on the scalp, elbows, and knees; cause is undetermined

vitiligo

pale, irregular patches of skin, and potentially autoimmune

what causes acne during puberty?

androgens trigger excess sebum, bringing keratin cells, and clogging the hair follicle

comedo

whiteheads and blacheads

papules (acne)

closed comedones

pustules

ruptured comedones, allowing bacteria in

seborrheic dermatitis/cradle cap

inflamed sebaceous glands and produce different sebum covering the face and scalp with greasy yellow scales

what is dandruff

keratinocytes and sebum clumps

alopecia

thinning or loss of hair

cause of alopecia

with age, follicles shrink and produce less dense hair

hyperhidrosis

excessive sweating in the armpits, palms. and soles of feet

what causes hyperhidrosis

eccrine glands are overstimulated by hypothalamus, weight gain, menopause, or drugs

onychomycosis/nail fungus

fungus growth underneath the nail causing yellow, brittle, cracking, and nail separation from the nail bed

paronychia/staph infection of nail base

fold and cuticle are swollen, red, and painful with pus underneath

ingrown toenail

nail growth misdirected into the skin and can get infected

diascopy

testing the vascularity of a lesion by pressing on it and seeing if it blanches

microscopic exam of skin

using skin scrapings under a microscope to find infection

culture

swabbing a lesion and using the sample to incubate a sample and diagnose the infection

biopsy

removing some or all of a lesion to inspect under a microscope

photodynamic therapy

high-intensity blue light killing bacteria in sebaceous glands; treats acne and precancerous lesions

laser therapy

treats birthmarks, skin disorders, warts, and vascular lesions

chemical peels

acid solution applied to skins surface and overtime reduces fine lines, wrinkles, sun damage, discoloration, etc.

cryotherapy

liquid nitrogen is sprayed onto the skin, causing the scabbing or peeling or superficial skin conditions

botox

cosmetic procedure that “freezes” muscle, reducing wrinkles and fine lines

dermal fillers

with age, subcutaneous fat dissolves and dermal fillers add more volume, making the skin look fuller

types of topical therapy

anesthetic (pain or itch relief), antibacterial, antifungal, antipruritic (itch relief), keratolytics (removes stratum corneum), parasiticides (kills parasites), retinoids (keratolytics used under physician supervision)

1st degree burn

superficial (epidermis only), redness, pain, slight edema, healing in 3-5 days, no scarring

2nd degree burn

epidermis and some of the dermis, redness, blisters, and severe pain, 2-3 weeks of healing, minimal scarring

3rd degree burns

epidermis, dermis and subcutaneous tissues, healing is long and requires skin graft

4th degree burn

destroys all dermal layers, tendons, muscle, and even bone sometimes

autograft

skin supplied from patient’s body, does not risk rejection

allograft

skin from another human (cadaver most likely) from skin banks; used for extensive burn damage

xenograft

skin graft from another species

rules of 9s (percentage of the body burned based on affected body surface)

head and neck = 9%

each arm = 9%

each leg = 18%

anterior trunk = 18%

posterior trunk = 18%

genitalia = 1%

as epidermis ages…

thickness>, number of melanocytes>, size of melanocytes <

as dermis ages…

blood vessels become fragile (easy bruising/bleeding), sebaceous glands produce less oil (drier skin), sweat glands produce less sweat (temp regulation)

as hypodermis ages…

subcutaneous fat dissolves, skin elasticity decreases, skin repair and wound healing takes longer

laceration

epidermal tear; epithelial cells split and fill gap

wound

deep cut into dermis or hypodermis, bleeding

clotting and scabbing

escaped blood forms a clot, cells clean debris and bacteria, clots hardens into scab, scab heals and prevents infection, new capillaries go to clot, new collagen fibers formed 3-4 days post and close the wound, wound becomes a scar

keloid

excessive fibrosis and excess scar tissue causing a raised, irregular, shiny scar

abdominoplasty

tummy tuck

blepharoplasty

correction of defects, specifically eyelid drooping

dermabrasion

removal of the upper layer of skin with a high-powered rotating brush

lipectomy

excision removal of fat

liposuction

fat removal with a suctioned hose

mammoplasty

alteration of the size/shape of breast

rhinoplasty

alteration of the size/shape of nose

functions of the skeletal system

support, protection, blood formation, mineral storage and balance, blood detoxification, osteocalcin regulation, movement

long bones

most common shape, longer than wide

short bones

almost as long as wide

diaphysis

shaft of the long bone, made up of compact (cortical) bone

epiphysis

ends of the bone, spongy (trabecular) bone

epiphyseal plate/line

point of growth, thin layers of cartilage cells that grow the bones lengthwise

periosteum

tough sheath of connective tissue that covers the surface of the bone to protect it and anchor nerves and blood vessels to the bone surface

medulla/medullary cavity

inside diaphysis, hollow cylinder containing bone marrow

haversian canals

system of canals for blood vessels to supply the bone with blood

fibrous joints

two bones tightly bound together by bands of fibrous tissue with no joint space