731 Tissue Injury and Healing

first phase of tissue injury

inflammatory response 0-4 days

signs and symptoms of inflammatory response phase

swelling, tenderness, redness, pain

second phase of tissue injury

fibroblastic-repair phase 2days-6weeks

signs and symptoms of fibro-blastic repair phase

cardinal signs such as tenderness, swelling, pain, etc are still there but getting better

third phase of tissue injury

maturation-remodeling phase 3weeks-2years

phagocytosis

eats up cells

histamine

causes vasodilation and increased cell permeability

cytokines

regulate leukocyte traffic to the site of injury

leukocytes

cleans up the damage cells

(factor that affects healing) extent of injury

the larger the size/severity, the longer it will take to heal

(factor that affects healing) edema

swelling causes increased pressure causing tissue separation, altered neuromuscular control, and impedes nutrition

(factor that affects healing) hemorrhage

occurs when blood vessels around the area are damaged; has same effects as edema

(factor that affects healing) poor vascular supply

poor healing without nutrients delivered to injured tissues via bloodstream

(factor that affects healing) separation of tissue

edges that are not close together will not heal

(factor that affects healing) muscle spasm

causes separation of the edges of tissue

(factor that affects healing) atrophy

occurs with injury and is important to strengthen and utilize early mobilization

(factor that affects healing) corticosteroids

use of an anti-inflammatory will discourage the initial inflammatory stages of healing

(factor that affects healing) keloids

thick scars that form due to the overproduction of collagen

(factor that affects healing) infection

delays healing and can lead to excessive scar formation

(factor that affects healing) humidity, climate, and oxygen tension

keeping wounds moist prevents scar formation

oxygen tension represents amount of oxygen in the blood which we want high-decreased hinders healing

(factor that affects healing) health, age, nutrition

healing capacity decreases with age

external medical condition (ex. diabetes) reduces healing capacity

nutrition and protein intake is important to promote healing

cartilage

is avascular and heals poorly; could take 2 months to 2 years

ligament

healing depends on blood supply and ligament location (days, months, years)

what ligament location heals better

intraarticular ligaments

muscle

has a good capacity for regeneration and healing (3 days to 8 weeks)

tendon

needs formation of a lot of collagen to heal (4 weeks to up to 2 years)

nerve

nerve fibers can regenerate but not the nerve cell (3-4mm of growth per day)

bone

blood vessels grow to heal tissue which then becomes ossified (3-8weeks)

skin

epidermis wounds heal quickly

deep dermis and subcutaneous wounds heal by stem cell and have a good capacity to heal because they are highly vascularized

what is key to good wound healing on skin

maintaining the proper environment (temperature, humidity, oxygen tension)